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Method for scrubbing pollutants from an exhaust gas stream
Microsoft Academic Search
This patent describes a method of treatment of an exhaust gas stream containing as pollutants at least one of the acidic oxides of sulfur, nitrogen, carbon, and halogens and acidic halogen compounds, whose temperature exceeds the dew point of the gas, for producing scrubbed exhaust and useful or benign by-products. It comprises: providing a basic aqueous slurry of ash, the
Automobile exhaust gas cleaner
SciTech Connect
A cleaner for exhaust gas is described comprising: first and second perforated baffle means supported in respective first and second housings, the first housing having an exhaust gas inlet, the second housing having an exhaust gas outlet, and the first housing being situated below the second housing and connected thereto to permit the flow of exhaust gas upwardly from the first housing to the second housing, means for spraying cleaning liquid onto the first perforated baffle means and for permitting the gas to permeate therethrough and then to flow downwardly around means for deflecting the gas before moving upwardly to the second housing, the sprayed liquid falling downwardly into sump means for receiving the sprayed liquid, means for spraying cleaning liquid onto the second perforated baffle means and for permitting the gas to permeate therethrough, the sprayed liquid falling downwardly into the sump means, and means for filtering pollutants from the exhaust gas.
Pickering, J.J.
Exhaust gas recirculator
An exhaust gas recirculator for an internal combustion engine having an exhaust pipe, an intake manifold and a carburetor throttle valve. The exhaust gas recirculator comprises an egr passage which makes the exhaust pipe communicate with the intake manifold, an egr controlling valve and an egr valve respectively arranged in the upper and lower portions of the egr passage. The egr valve operates in association with the carburetor throttle valve for metering the flow of egr gas. The egr controlling valve is separated by a diaphragm into an egr gas chamber communicating with the egr passage between the egr controlling valve and the egr valve and a negative pressure chamber communicating with the intake manifold. The negative pressure chamber contains a compression spring, and the diaphragm is connected with a valve member through a rod upon which is disposed a stopper to serve as a different seal in place of the valve member to close off the exhaust gas passage, which valve member and stopper are constructed to be opened and closed by pressure difference between the egr gas chamber and the negative pressure chamber and by elastic force of the compression spring. The egr controlling valve functions to control the pressure difference around the egr valve to be constant.
Suda, K.
Exhaust gas recirculation system
An engine exhaust gas recirculation (EGR) system is provided in which a sonic flow EGR valve is moved to open positions to establish a different constant rate of flow at each open position of the EGR valve in response to air pressure acting on a servo means secured to the valve, the air pressure force being controlled by changes in a control vacuum opposing the air pressure force and modified by an air bleed device as a function of changes in engine exhaust gas backpressure levels, to provide an EGR valve movement that varies essentially in proportion to changes in engine air flow.
Rachedi, S.H.
Mechanisms of Exhaust Pollutants and Plume Formation in Continuous Combustion.
National Technical Information Service (NTIS)
The investigation of exhaust pollutant and plume formation in continuous combustion is a combined analytical and experimental study of turbulent, backmixed combustion in gas turbines. Experiments are being conducted operating with premixed methane/air and...
G. S. Samuelsen R. E. Peck
Potpourri that is exhaust gas
The literature of the subject contains much information about the individual reactive components of exhaust gas and ''total'' and ''average'' emissions. However, there is a notable lack of information concerning the myriad compositions and hydrocarbon distributions that accompany changes in engine mode and that define the variable character of an exhaust gas stream. Information pertinent to the latter is given
R. S. Hurn; C. L. Dozois; J. O. Chase; C. F. Ellis; P. E. Ferrin
Feedback control system for gas flow in internal combustion engine for purpose of exhaust gas purification
A feedback control system for controlling the flow rate of a gas which is either drawn from or introduced into an exhaust passage of an internal combustion engine for the purpose of lessening pollutants in the exhaust gas. The control system is embodied either as an exhaust gas recirculation control system or a secondary air injection control system and in
Y. Matsubara; H. Nagaishi; S. Suzuki
Capture efficiency measurement of pollutants over a workbench with the reinforced slot exhaust system
NASA Astrophysics Data System (ADS)
The paper deals with the measurement of the capture efficiency of pollutants by the slot reinforced exhaust system situated in two positions over the workbench. The slot reinforced exhaust system, which is known as REEXS, is the traditional slot exhaust hood equipped with an air supply inlet that intensifies exhausting along the axis of the exhaust hood. It can operate in traditional or reinforced exhaust modes. Measurements were made for the same air velocity in the suction slot and with the different momentum flux ratio of supplied and exhausted air flow. The tracer gas method was used for the capture efficiency measurement of the system. As the tracer gas the carbon dioxide was chosen. The knowledge of the shape and range of the effective exhaust area for various configurations in front of the exhaust hood is important for the exhaust hood setting according to a source of pollutants.
Pech, O.; Pavelek, M.
System for Removing Pollutants from Incinerator Exhaust
NASA Technical Reports Server (NTRS)
A system for removing pollutants -- primarily sulfur dioxide and mixed oxides of nitrogen (NOx) -- from incinerator exhaust has been demonstrated. The system is also designed secondarily to remove particles, hydrocarbons, and CO. The system is intended for use in an enclosed environment, for which a prior NOx-and-SO2-removal system designed for industrial settings would not be suitable.
Wickham, David t.; Bahr, James; Dubovik, Rita; Gebhard, Steven C.; Lind, Jeffrey
Turbocharged engine exhaust gas recirculation system
Improved exhaust gas recirculation systems for turbocharged gas engines that include an exhaust pipe, a turbocharger connected thereto, and a carburetor connected with a source of gas for the engine. The recirculation system includes an air conduit extending from the turbocharger compressor discharge to a venturi, an exhaust gas conduit that extends from a connection with the exhaust pipe between
High speed exhaust gas recirculation valve
In order to minimize pollutants such as Nox, internal combustion engines typically include an exhaust gas recirculation (EGR) valve that can be used to redirect a portion of exhaust gases to an intake conduit, such as an intake manifold, so that the redirected exhaust gases will be recycled. It is desirable to have an EGR valve with fast-acting capabilities, and it is also desirable to have the EGR valve take up as little space as possible. An exhaust gas recirculation valve is provided that includes an exhaust passage tube, a valve element pivotally mounted within the exhaust passage tube, a linear actuator; and a gear train. The gear train includes a rack gear operatively connected to the linear actuator, and at least one rotatable gear meshing with the rack gear and operatively connected to the valve element to cause rotation of the valve element upon actuation of the linear actuator. The apparatus provides a highly compact package having a high-speed valve actuation capability.
Fensom, Rod (Peterborough, GB); Kidder, David J. (Peterborough, GB)
Purification of exhaust air containing organic pollutants in a trickle-bed bioreactor
This paper reports experiments on the purification of exhaust air containing organic pollutants by a new biological process using a trickle-bed reactor. Pollutant-specific microorganisms in high concentration were fixed to a suitable bed. The absorption and conversion of propionaldehyde as a model pollutant was measured by systematic variation of the gas and liquid flow rates in the reaction system. At
K. Kirchner; C. A. Gossen; H.-J. Rehm
Exhaust gas recirculation system for an internal combustion engine
An exhaust gas recirculation system for an internal combustion engine comprises an exhaust driven turbocharger having a low pressure turbine outlet in fluid communication with an exhaust gas conduit. The turbocharger also includes a low pressure compressor intake and a high pressure compressor outlet in communication with an intake air conduit. An exhaust gas recirculation conduit fluidly communicates with the exhaust gas conduit to divert a portion of exhaust gas to a low pressure exhaust gas recirculation branch extending between the exhaust gas recirculation conduit and an engine intake system for delivery of exhaust gas thereto. A high pressure exhaust gas recirculation branch extends between the exhaust gas recirculation conduit and the compressor intake and delivers exhaust gas to the compressor for mixing with a compressed intake charge for delivery to the intake system.
Wu, Ko-Jen
Reduction of fuel consumption and exhaust pollutant using intelligent transport systems.
Greenhouse gas emitted by the transport sector around the world is a serious issue of concern. To minimize such emission the automobile engineers have been working relentlessly. Researchers have been trying hard to switch fossil fuel to alternative fuels and attempting to various driving strategies to make traffic flow smooth and to reduce traffic congestion and emission of greenhouse gas. Automobile emits a massive amount of pollutants such as Carbon Monoxide (CO), hydrocarbons (HC), carbon dioxide (CO2), particulate matter (PM), and oxides of nitrogen (NO x ). Intelligent transport system (ITS) technologies can be implemented to lower pollutant emissions and reduction of fuel consumption. This paper investigates the ITS techniques and technologies for the reduction of fuel consumption and minimization of the exhaust pollutant. It highlights the environmental impact of the ITS application to provide the state-of-art green solution. A case study also advocates that ITS technology reduces fuel consumption and exhaust pollutant in the urban environment. PMID:25032239
Nasir, Mostofa Kamal; Md Noor, Rafidah; Kalam, M A; Masum, B M
Reduction of Fuel Consumption and Exhaust Pollutant Using Intelligent Transport Systems
PubMed Central
Greenhouse gas emitted by the transport sector around the world is a serious issue of concern. To minimize such emission the automobile engineers have been working relentlessly. Researchers have been trying hard to switch fossil fuel to alternative fuels and attempting to various driving strategies to make traffic flow smooth and to reduce traffic congestion and emission of greenhouse gas. Automobile emits a massive amount of pollutants such as Carbon Monoxide (CO), hydrocarbons (HC), carbon dioxide (CO2), particulate matter (PM), and oxides of nitrogen (NOx). Intelligent transport system (ITS) technologies can be implemented to lower pollutant emissions and reduction of fuel consumption. This paper investigates the ITS techniques and technologies for the reduction of fuel consumption and minimization of the exhaust pollutant. It highlights the environmental impact of the ITS application to provide the state-of-art green solution. A case study also advocates that ITS technology reduces fuel consumption and exhaust pollutant in the urban environment.
Nasir, Mostofa Kamal; Md Noor, Rafidah; Kalam, M. A.; Masum, B. M.
Fast response exhaust gas recirculation (EGR) system
This patent describes an exhaust gas recirculation (EGR) control for an automotive type internal combustion engine. It comprises: a gas induction passage connected to the engine intake manifold at one end, an EGR passage connected at one end to exhaust gases from the engine combustion chamber, the other end of the induction passage being bifurcated to form ambient air and EGR branch passages, means connecting the ambient air branch passage to ambient air, means connecting the EGR branch passage to the other end of the EGR passage whereby ambient air and EGR gases combine to form a gas charge inducted into the engine.
Wade, W.R.
Gas turbine exhaust nozzle. [for noise reduction
An elongated hollow string is disposed in an exhaust nozzle combustion chamber and communicates with an air source through hollow struts at one end. The other end of the string is bell-mouth shaped and extends over the front portion of a nozzle plug. The bell-mouth may be formed by pivotally mounted flaps or leaves which are used to vary the exhaust throat area and the area between the plug and the leaves. Air from the engine inlet flows into the string and also between the combustion chamber and a housing disposed around the chamber. The air cools the plug and serves as a low velocity inner core of secondary gas to provide noise reduction for the primary exhaust gas while the other air, when it exits from the nozzle, forms an outer low velocity layer to further reduce noise. The structure produces increased thrust in a turbojet or turbofan engine.
Straight, D. M. (inventor)
40 CFR 1065.127 - Exhaust gas recirculation.
Code of Federal Regulations, 2013 CFR
...Exhaust gas recirculation. Use the exhaust gas recirculation (EGR) system installed with the engine or one that represents a typical in-use configuration. This includes any applicable EGR cooling...
46 CFR 63.25-7 - Exhaust gas boilers.
... 2013-10-01 false Exhaust gas boilers. 63.25-7 Section 63.25-7...MARINE ENGINEERING AUTOMATIC AUXILIARY BOILERS Requirements for Specific Types of Automatic Auxiliary Boilers § 63.25-7 Exhaust gas...
Exhaust gas composition measurement. [liquid monopropellant rocket engine performance tests
The design, installation, checkout, and operation of an exhaust gas composition measurement system for collecting and analyzing the exhaust gas from a liquid monopropellant rocket engine are described. Design guidelines are given for the critical components of each portion of the system to provide an exhaust gas composition measurement which meets the performance criteria specified.
In an internal combustion engine having an intake passage provided therein with a throttle valve for controlling intake flow of air or an air-fuel mixture passing therethrough toward engine cylinders and an exhaust passage, an exhaust gas recirculation system comprises first means for conducting a portion of the exhaust gases from the exhaust passage into the intake passage downstream of
Exhaust gas recirculation system for diesel engine
An exhaust gas recirculation control system calculates a target EGR ratio value based upon engine operating parameters and maintains the EGR ratio at the target EGR ratio value. Each time the vehicle travels a predetermined distance, the control system calculates an actual EGR ratio value and corrects the target EGR ratio value to reduce a deviation between the target and actual EGR ratio values to zero.
Masaki, K.; Yasuhara, S.
Interrelation of exhaust-gas constituents
This report presents the results of an investigation conducted to determine the interrelation of the constituents of the exhaust gases of internal-combustion engines and the effect of engine performance on these relations. Six single-cylinder, liquid-cooled tests engines and one 9-cylinder radial air-cooled engine were tested. Various types of combustion chambers were used and the engines were operated at compression ratios from 5.1 to 7.0 using spark ignition and from 13.5 to 15.6 using compression ignition. The investigation covered a range of engine speeds from 1,500 to 2,100 r.p.m. The fuels used were two grades of aviation gasoline, auto diesel fuel, and laboratory diesel fuel. Power, friction, and fuel-consumption data were obtained from the single-cylinder engines at the same time that the exhaust-gas samples were collected.
Gerrish, Harold C; Voss, Fred
Pollutant Removal Efficiency of Residential Cooking Exhaust Hoods
Capture efficiency (CE) of exhaust from a natural gas cooking range was quantified for three common designs of residential range hoods in laboratory experiments: (A) microwave exhaust combination; (B) short hood with grease-screen-covered air inlet at bottom; and (C) deep, open hood exhausting at top. Devices were evaluated at varying installation heights, at highest and lowest fan settings, and with the hood installed 15 cm away from back wall with intent to improve CE for front burners. Each configuration was evaluated for the oven and for three cooktop burner combinations (two back, two front, one front and one back). At highest fan settings and standard installation against the wall, Hoods A and C captured back cooktop burner exhaust at > 90 percent and Hood B at > 80 percent. In this configuration, CE for front burner exhaust was 73-78 percent for Hoods A and C but only 46-63 percent for Hood B. CEs followed similar patterns but were substantially lower on the lowest fan speed. Installing the hood away from the wall improved CE for oven and front burners on Hood A at low speed, but substantially reduced CE for back burners for all hoods at low and high speed.
Singer, Brett C.; Sherman, Alexander D.; Hotchi, Toshifumi; Sullivan, Douglas P.
Dynamics of exhaust gas generated by arc extinction
We report an analytical study on hot gas exhaust process of a SF6 gas circuit breaker (GCB), after current interruption. The behavior of the hot gas has been studied based on measured gas temperature and simulation results of gas composition. We also propose a mechanism of interaction between the hot gas and pressure waves, which causes a self-blocking of the exhaust gas. During the heavy current interruption, the flow model suggests that the dielectric strength of the hot gas is affected by the pressure waves that are generated by the hot gas exhaustion. We believe that the results reported in this article provide guidance for the optimum structure of the exhaust chamber for small size GCB, operating at very high interrupting current.
Hayashi, Yasushi; Watanabe, Masato; Okino, Akitoshi; Hotta, Eiki
Internal combustion engine having exhaust gas recirculation system
An internal combustion engine has an exhaust gas recirculation system including a recirculation valve for controlling the amount of exhaust gas returned to the intake system. The position or opening of the valve is controlled to a desired position in accordance with a memory in a memory device storing desired valve positions under various combinations of the engine load and
K. Iida; K. Okazaki; Y. Yada
Using exhaust gas recirculation in internal combustion engines: a review
The aim of this work is to review the potential of exhaust gas recirculation (EGR) to reduce the exhaust emissions, particularly NOX emissions, and to delimit the application range of this technique. A detailed analysis of previous and current results of EGR effects on the emissions and performance of Diesel engines, spark ignition engines and duel fuel engines is introduced.
G. H. Abd-Alla
Development of Exhaust Gas Driven Absorption Chiller-Heater
Waste heat from co-generation systems are usually recovered by hot water or steam, those are used to drive absorption refrigerators at cooling time, and those are used for heating via heat exchangers at heating time. However waste heat from micro gas turbines are discharged in the form of exhaust gas, it is simple that exhaust gas is directly supplied to absorption chiller-heaters. In the first report we studied cooling cycle, and this second paper, we evaluated various absorption heating cycles for exhaust gas driven absorption chiller-heaters, and adopted one of these cycles for the prototype machine. Also, we experimented with the prototype for wide range condition and got the heating characteristics. Based on the experimental data, we developed a simulation model of the static characteristics, and then studied how to increase the output by limited exhaust gas.
Inoue, Naoyuki; Endou, Tetsuya; Saito, Kiyoshi; Kawai, Sunao
Exhaust Gas Energy Recovery Technology Applications
Exhaust waste heat recovery systems have the potential to significantly improve vehicle fuel economy for conventional and hybrid electric powertrains spanning passenger to heavy truck applications. This chapter discusses thermodynamic considerations and three classes of energy recovery technologies which are under development for vehicle applications. More specifically, this chapter describes the state-of-the-art in exhaust WHR as well as challenges and opportunities for thermodynamic power cycles, thermoelectric devices, and turbo-compounding systems.
Wagner, Robert M [ORNL] [ORNL; Szybist, James P [ORNL] [ORNL
40 CFR 86.111-94 - Exhaust gas analytical system.
Code of Federal Regulations, 2010 CFR
...ionization detector. The analysis for formaldehyde is performed using high pressure liquid chromatography (HPLC) of 2,4-dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas analytical system...
40 CFR 86.511-90 - Exhaust gas analytical system.
...ionization detector. The analysis for formaldehyde is performed using high pressure liquid chromatography (HPLC) of 2,4- dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas analytical system...
40 CFR 86.111-90 - Exhaust gas analytical system.
Measuring Carbon Monoxide in Auto Exhaust by Gas Chromatography.
ERIC Educational Resources Information Center
Presents a simple and reliable technique using commonly available equipment for monitoring carbon monoxide in automobile exhaust. The experiment utilizes a gas chromatograph and a thermal conductivity detector (TCD). (DDR)
Jaffe, Dan; Herndon, Scott
Exhaust Emissions from Williams Research Corporation Gas Turbine Engines.
The exhaust emissions of several different models of gas turbine engines under development or in production were measured. The emissions measured were carbon dioxide, carbon monoxide, unburned hydrocarbons, and the oxides of nitrogen. The results are pres...
H. B. Moore J. A. Royer
... Requirements for Specific Types of Automatic Auxiliary Boilers...b) Controls. Each drum type exhaust gas steam boiler...sufficient to ensure proper heat transfer. The system must adequately...which results in inadequate heat transfer, a high temperature...
...a FID) for the determination of CH4, non-dispersive infrared analyzers (NDIR) for the determination of CO and CO2 ...4-dinitrophenylhydrazine (DNPH) derivatives using ultraviolet (UV) detection. The exhaust gas analytical system shall conform to the...
Method and apparatus for processing exhaust gas with corona discharge
The present invention is placing a catalyst coating upon surfaces surrounding a volume containing corona discharge. In addition, the electrodes are coated with a robust dielectric material. Further, the electrodes are arranged so that at least a surface portion of each electrode extends into a flow path of the exhaust gas to be treated and there is only exhaust gas in the volume between each pair of electrodes. 12 figs.
Barlow, S.E.; Orlando, T.M.; Tonkyn, R.G.
Real-Time Measurement of Vehicle Exhaust Gas Flow
A flow measurement system was developed to measure, in real-time, the exhaust gas flow from vehicies. This new system was based on the vortex shedding principle using ultrasonic detectors for sensing the shed vortices. The flow meter was designed to measure flow over a range of 1 to 366 Ips with an inaccuracy of ~1o/0 of reading. Additionally, the meter was engineered to cause minimal pressure drop (less than 125mm of water), to function in a high temperature environment (up to 650oC) with thermal transients of 15 oC/s, and to have a response time of 0.1 seconds for a 10% to 90!40 step change. The flow meter was also configured to measure hi-directional flow. Several flow meter prototypes were fabricated, tested, and calibrated in air, simulated exhaust gas, and actual exhaust gas. Testing included gas temperatures to 600oC, step response experiments, and flow rates from O to 360 lps in air and exhaust gas. Two prototypes have been tested extensively at NIST and two additional meters have been installed in exhaust gas flow lines for over one year. This new flow meter design has shown to be accurate, durabIe, fast responding, and to have a wide rangeabi~ity.
Hardy, J.E.; Hylton, J.O.; Joy, R.D.; McKnight, T.E.
Selective mixed potential ammonia exhaust gas sensor
Novel selective ammonia sensors with high potential for long-term stability in harsh exhaust environments are introduced. The sensor bases on the mixed potential effect. In contrast to common sensors, the electrode functionalities electrical conductivity, selective catalytic activity, and electrochemical activity combined with long-term stability are separated. For that reason, one of the two electrodes is covered by a well-known porous
Daniela Sch�nauer; Kerstin Wiesner; Maximilian Fleischer; Ralf Moos
Exhaust gas purifying system for internal combustion engine
An exhaust gas purifying system for an automobile engine including at least first and second engine cylinder has a shutter valve for interrupting the supply of a combustible air-fuel mixture to the first engine cylinder during a particular engine operating condition, a three-way electromagnetically operated valve for controlling the operation of the shutter valve, and a secondary air supply unit including a switching valve for selectively supplying a secondary air to a portion of an exhaust passage upstream of at least one catalyst unit disposed in the exhaust passage.
Higashi, H.; Iida, K.; Shiraishi, H.
Exhaust gas management systems for underwater heat engines
In hydrocarbon fuelled air-independent power system research, whether an internal\\/external combustion heat engine, or fuel cell, an exhaust gas management system is required. In previous research many techniques have been proposed for the control and\\/or removal of the combustion generated exhaust products, notably heat exchangers and carbon dioxide separation techniques. However, there has been little research on the merits of
I. J. Potter; Eric Clavelle; Graham T. Reader; J. Kady; M. Carl
Low-pressure-ratio regenerative exhaust-heated gas turbine
A design study of coal-burning gas-turbine engines using the exhaust-heated cycle and state-of-the-art components has been completed. In addition, some initial experiments on a type of rotary ceramic-matrix regenerator that would be used to transfer heat from the products of coal combustion in the hot turbine exhaust to the cool compressed air have been conducted. Highly favorable results have been obtained on all aspects on which definite conclusions could be drawn.
Tampe, L.A.; Frenkel, R.G.; Kowalick, D.J.; Nahatis, H.M.; Silverstein, S.M.; Wilson, D.G.
30 CFR 36.43 - Determination of exhaust-gas composition.
...equilibrium before exhaust-gas samples are collected or other...volume, of Pittsburgh natural gas (see footnote 3) in the...equipment. (b) Exhaust-gas samples shall be analyzed for carbon dioxide, oxygen, carbon monoxide,...
Diver's Suit Excess Gas Exhaust Valve.
A valve for controlling venting of excess gas from a diving suit includes a valve body housing first and second rubber check valves arranged in series. A control knob is rotatable on the valve body to selectively open or close outlet ports for venting gas...
C. H. Dickson
Selective ammonia exhaust gas sensor for automotive applications
In order to meet future NOx emission standards for commercial vehicles, so called urea selective catalytic reduction (SCR) systems will be introduced. In the SCR converter ammonia serves as a reducing agent for selective NOx reduction. An ammonia exhaust gas sensor is required to optimize the injected amount of urea and to assure that no ammonia emissions occur. This paper
Ralf Moos; Ralf M�ller; Carsten Plog; Aleksandar Knezevic; Holger Leye; Eckard Irion; Tillmann Braun; Klaus-J�rgen Marquardt; Klaus Binder
Removal of methane from compressed natural gas fueled vehicle exhaust
The objective of this paper is to investigate the modes of methane (CH[sub 4]) removal from simulated compressed natural gas (CNG) fueled vehicle exhaust under net oxidizing, net reducing, and stoichiometric conditions. Model reaction studies were conducted. The results suggest that the oxidation of methane with oxygen contributes to the removal of methane under net oxidizing conditions. In contrast, the
S. Subramanian; R. J. Kudla; M. S. Chattha
A flow measurement system was developed to measure, in real-time, the exhaust gas flow from vehicies. This new system was based on the vortex shedding principle using ultrasonic detectors for sensing the shed vortices. The flow meter was designed to measure flow over a range of 1 to 366 Ips with an inaccuracy of ~1o\\/0 of reading. Additionally, the meter
J. E. Hardy; J. O. Hylton; R. D. Joy; T. E. McKnight
An exhaust gas purifying system for an automobile engine including at least first and second engine cylinder has a shutter valve for interrupting the supply of a combustible air-fuel mixture to the first engine cylinder during a particular engine operating condition, a three-way electromagnetically operated valve for controlling the operation of the shutter valve, and a secondary air supply unit
H. Higashi; K. Iida; H. Shiraishi
Pollutants in incineration flue gas.
Previous studies have shown that pollutants from incineration include heavy metals, organic compounds, particulate and acid gas. However, most studies on a single pollutant, it is rare for a study to concentrate on all possible pollutants and the relations between these pollutants under various incineration conditions. The objective of this work was to experimentally study the effect of different operating conditions on the pollutants emitted during incineration and the relations between these pollutants. The operating conditions of the experiments included the temperature of the combustion chamber and the species of organics. The findings indicated that the concentration of hydrogen chloride (HCl) in the presence of polyvinyl chloride (PVC) was higher than that of sodium chloride (NaCl). Regardless of what Cl-containing feedstock was added, the concentration of chromium (Cr) was constant. When organic chloride was added, Cr was the main metallic element which influenced the formation of polycyclic aromatic hydrocarbons (PAHs). On the other hand, when inorganic chloride (NaCl) was added, lead (Pb) was the major element. PMID:11240066
Wey, M Y; Ou, W Y; Liu, Z S; Tseng, H H; Yang, W Y; Chiang, B C
Electron beam treatment of exhaust gas with high NOx concentration
Simulated exhaust gases with a high NOx concentration, ranging from 200 to 1700 ppmv, were irradiated by an electron beam from an accelerator. In the first part of this study, only exhaust gases were treated. Low NOx removal efficiencies were obtained for high NOx concentrations, even with high irradiation doses applied. In the second part of study, gaseous ammonia or/and vapor ethanol were added to the exhaust gas before its inlet to the plasma reactor. These additions significantly enhanced the NOx removal efficiency. The synergistic effect of high SO2 concentration on NOx removal was observed. The combination of electron beam treatment with the introduction of the above additions and with the performance of irradiation under optimal parameters ensured high NOx removal efficiency without the application of a solid-state catalyst.
Licki, Janusz; Chmielewski, Andrzej G.; Pawelec, Andrzej; Zimek, Zbigniew; Witman, Sylwia
Integrated exhaust gas recirculation and charge cooling system
An intake system for an internal combustion engine comprises an exhaust driven turbocharger configured to deliver compressed intake charge, comprising exhaust gas from the exhaust system and ambient air, through an intake charge conduit and to cylinders of the internal combustion engine. An intake charge cooler is in fluid communication with the intake charge conduit. A cooling system, independent of the cooling system for the internal combustion engine, is in fluid communication with the intake charge cooler through a cooling system conduit. A coolant pump delivers a low temperature cooling medium from the cooling system to and through the intake charge cooler for the transfer of heat from the compressed intake charge thereto. A low temperature cooler receives the heated cooling medium through the cooling system conduit for the transfer or heat therefrom.
Exhaust gas treatment in testing nuclear rocket engines
With the exception of the last test series of the Rover program, Nuclear Furnace 1, test-reactor and rocket engine hydrogen gas exhaust generated during the Rover/NERVA program was released directly to the atmosphere, without removal of the associated fission products and other radioactive debris. Current rules for nuclear facilities (DOE Order 5480.6) are far more protective of the general environment; even with the remoteness of the Nevada Test Site, introduction of potentially hazardous quantities of radioactive waste into the atmosphere must be scrupulously avoided. The Rocketdyne treatment concept features a diffuser to provide altitude simulation and pressure recovery, a series of heat exchangers to gradually cool the exhaust gas stream to 100 K, and an activated charcoal bed for adsorption of inert gases. A hydrogen-gas fed ejector provides auxiliary pumping for startup and shutdown of the engine. Supplemental filtration to remove particulates and condensed phases may be added at appropriate locations in the system. The clean hydrogen may be exhausted to the atmosphere and flared, or the gas may be condensed and stored for reuse in testing. The latter approach totally isolates the working gas from the environment.
Zweig, H.R.; Fischler, S.; Wagner, W.R. (Rocketdyne Division, Rockwell International Corporation, 6633 Canoga Avenue, P.O. Box 7922, Canoga Park, California 91309-7922 (United States))
Zweig, Herbert R.; Fischler, Stanley; Wagner, William R.
40 CFR 86.209-94 - Exhaust gas sampling system; gasoline-fueled vehicles.
...false Exhaust gas sampling system; gasoline-fueled vehicles. 86.209-94...Regulations for 1994 and Later Model Year Gasoline-Fueled New Light-Duty Vehicles...209-94 Exhaust gas sampling system; gasoline-fueled vehicles. The...
Air pollution and lung cancer: diesel exhaust, coal combustion
It is known, that cigarette smoking is by far the most important cause of lung cancer and that about a dozen occupational exposures are also established as causes of this disease. There has been continuing uncertainty about the role of general air pollution. During the past few years, this uncertainty has been compounded with anxiety that the increasing use of
Ian T. T. Higgins
Diesel Exhaust Activates & Primes Microglia: Air Pollution, Neuroinflammation, & Regulation of Dopaminergic Neurotoxicity
EPA Science Inventory
Air pollution is linked to central nervous system (CNS) disease, but the mechanisms responsible are poorly understood. Rats exposed to Diesel Exhaust (DE, 2.0,0.5, and 0 mg/m3) by inhalation over 4 weeks demonstrated elevated levels of whole brain IL-6 protein, nitrated proteins,...
Gas pollution control apparatus and method and wood drying system employing same
Pollution control apparatus and method are disclosed in which hot exhaust gas containing pollutants including solid particles and hydrocarbon vapors is treated by transmitting such exhaust gas through a container containing wood members, such as wood chips, which serve as a filter media for filtering out such pollutants by causing such solids to deposit and such hydrocarbon vapors to condense upon the surface of the wood members. The contaminated wood chips are discharged from the filter and further processed into chip board or other commercial wood products thereby disposing of the pollutants. Lumber may be used as the wood members of the filter in a lumber kiln by deposition of solid particles on the rough surface of such lumber. The contaminated surfaces of the lumber are removed by a planer which produces a smooth finished lumber and contaminated wood chips that may be processed into chip board or other commercial wood products. A wood drying system employing such pollution control apparatus and method includes a hot air dryer for wood or other organic material, such as a wood chip rotary dryer or a wood veneer dryer, which produces hot exhaust gases containing pollutants including hydrocarbon vapors and solid particles. This hot exhaust air is transmitted through a lumber kiln to dry lumber thereby conserving heat energy and causing solid particle pollutants to deposit on the surface of the lumber. The kiln exhaust air containing solid and hydrocarbon vapor pollutants is then transmitted up through a filter stack of wood chips.
Eatherton, J.R.
30 CFR 36.47 - Tests of exhaust-gas cooling system.
...2013-07-01 false Tests of exhaust-gas cooling system. 36.47 Section 36.47 ...Requirements § 36.47 Tests of exhaust-gas cooling system. (a) The adequacy of the exhaust-gas cooling system and its components shall...
Vehicle exhaust gas chemical sensors using acoustic wave resonators
Under Sandia`s Laboratory Directed Research and Development (LDRD) program, novel acoustic wave-based sensors were explored for detecting gaseous chemical species in vehicle exhaust streams. The need exists for on-line, real-time monitors to continuously analyze the toxic exhaust gases -- nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbons (HC) -- for determining catalytic converter efficiency, documenting compliance to emission regulations, and optimizing engine performance through feedback control. In this project, the authors adapted existing acoustic wave chemical sensor technology to the high temperature environment and investigated new robust sensor materials for improving gas detection sensitivity and selectivity. This report describes one new sensor that has potential use as an exhaust stream residual hydrocarbon monitor. The sensor consists of a thickness shear mode (TSM) quartz resonator coated with a thin mesoporous silica layer ion-exchanged with palladium ions. When operated at temperatures above 300 C, the high surface area film catalyzes the combustion of the hydrocarbon vapors in the presence of oxygen. The sensor acts as a calorimeter as the exothermic reaction slightly increases the temperature, stressing the sensor surface, and producing a measurable deviation in the resonator frequency. Sensitivities as high as 0.44 (ppm-{Delta}f) and (ppm-gas) have been measured for propylene gas, with minimum detectable signals of < 50 ppm of propylene at 500 C.
Cernosek, R.W.; Small, J.H.; Sawyer, P.S.; Bigbie, J.R. [Sandia National Labs., Albuquerque, NM (United States); Anderson, M.T. [3M Industrial and Consumer Sector Research Lab., St. Paul, MN (United States)
Process for the separation of chlorine, fluorine and sulphur from fuel gas flue or exhaust gas
Fuel gas produced in a coal distillation or gasification plant is fed to a power plant and chlorine, fluorine, sulphur and compounds thereof in the fuel gas are separated from the fuel gas, and also from flue or exhaust gas emanating from the power plant, in two stages. In a first stage, chlorine and fluorine and their compounds are separated,
J. Poller; K. Weinziel
Exhaust gas bypass valve control for thermoelectric generator
A method of controlling engine exhaust flow through at least one of an exhaust bypass and a thermoelectric device via a bypass valve is provided. The method includes: determining a mass flow of exhaust exiting an engine; determining a desired exhaust pressure based on the mass flow of exhaust; comparing the desired exhaust pressure to a determined exhaust pressure; and determining a bypass valve control value based on the comparing, wherein the bypass valve control value is used to control the bypass valve.
Reynolds, Michael G; Yang, Jihui; Meisner, Greogry P.; Stabler, Francis R.; De Bock, Hendrik Pieter (Peter) Jacobus; Anderson, Todd Alan
A novel four-way combining catalysts for simultaneous removal of exhaust pollutants from diesel engine.
A novel four-way combining catalysts containing double layers was applied to simultaneously remove four kinds of exhaust pollutants (NOx, CO, HC and PM) emitted from diesel engine. The four-way catalysts were characterized using scanning electron microscope (SEM) and Ultraviolet visible diffuse reflectance spectroscopy (UV-Vis DRS). Their catalytic performances were evaluated by temperature-programmed reaction technology. The double layer catalysts could effectively remove the four main pollutants. The highest catalytic activity was given by the two-layered catalysts of La0.6K0.4CoO3/Al2O3 and W/HZSM-5. Under the simulated exhaust gases conditions, the peak temperature of the soot combustion was 421 degrees C, the maximal conversion of NO to N2 was 74%, the temperature of the HC total conversion was 357 degrees C, and the maximum conversion ratio of CO was 99%. PMID:21175003
Liu, Jian; Xu, Jie; Zhao, Zhen; Duan, Aijun; Jiang, Guiyuan; Jing, Yanni
Treating exhaust gas from a pressurized fluidized bed reaction system
Hot gases from a pressurized fluidized bed reactor system are purified. Under super atmospheric pressure conditions hot exhaust gases are passed through a particle separator, forming a filtrate cake on the surface of the separator, and a reducing agent--such as an NO{sub x} reducing agent (like ammonia)--is introduced into the exhaust gases just prior to or just after particle separation. The retention time of the introduced reducing agent is enhanced by providing a low gas velocity (e.g. about 1--20 cm/s) during passage of the gas through the filtrate cake while at super atmospheric pressure. Separation takes place within a distinct pressure vessel, the interior of which is at a pressure of about 2--100 bar, and introduction of reducing agent can take place at multiple locations (one associated with each filter element in the pressure vessel), or at one or more locations just prior to passage of clean gas out of the pressure vessel (typically passed to a turbine). 8 figs.
Isaksson, J.; Koskinen, J.
Hot gases from a pressurized fluidized bed reactor system are purified. Under superatmospheric pressure conditions hot exhaust gases are passed through a particle separator, forming a flitrate cake on the surface of the separator, and a reducing agent--such as an NO.sub.x reducing agent (like ammonia), is introduced into the exhaust gases just prior to or just after particle separation. The retention time of the introduced reducing agent is enhanced by providing a low gas velocity (e.g. about 1-20 cm/s) during passage of the gas through the filtrate cake while at superatmospheric pressure. Separation takes place within a distinct pressure vessel the interior of which is at a pressure of about 2-100 bar, and-introduction of reducing agent can take place at multiple locations (one associated with each filter element in the pressure vessel), or at one or more locations just prior to passage of clean gas out of the pressure vessel (typically passed to a turbine).
Isaksson, Juhani (Karhula, FI); Koskinen, Jari (Karhula, FI)
Pollutants from Methane Fueled Gas Turbine Combustion.
The air pollution characteristics of a model gas turbine type combustor using methane as fuel were studied in this investigation. Detailed information regarding gas compositions at various locations within the combustor and direct measurement of temperatu...
P. G. Parikh R. F. Saw A. L. London
Measurement of Gas-phase Acids in Diesel Exhaust
Gas-phase acids were measured using chemical ionization mass spectrometry (CIMS) as part of the Diesel Engine Emission Research Experiment (DEERE). The CIMS technique, utilizing acetate ion (CH3COO-) as a reagent ion, proved to be a rapid (measurements on the order of seconds) and sensitive (several counts/pptv) method of quantifying the acid emissions. Diluted diesel exhaust measurements were made from a Constant Volume Sampling dilution tunnel using a light duty (1.9L turbocharged Volkswagen Jetta TDI) diesel engine equipped with an OEM diesel oxidation catalyst and exhaust gas recirculation, mounted on an engine dynamometer. Acids measured included isocyanic, nitrous, nitric, propionic and sum of lactic and oxalic, as well as other unidentified compounds. Complimentary measurements of CO, CO2, Total Hydrocarbon (THC), and NOx, were also performed. Several engine modes (different engine rpm and torque outputs) at steady state were examined to determine their effect on acid emissions. Emission rates with respect to NOx and fuel based emission factors were determined. Measurements of HONO fuel emission factors agree well with real-world measurements within a traffic tunnel.1 The first estimate of isocyanic acid emission factors from a diesel engine is reported, and suggests that the emission of this highly toxic compound in diesel exhaust should not be ignored. 1. Kurtenbach, R., Becker, K. H., Gomes, J. A. G., Kleffmann, J.,Lorzer, J. C., Spittler, M., Wiesen, P., Ackermann, R., Geyer, A.,and Platt, U.: Investigations of emissions and heterogeneous formation of HONO in a road traffic tunnel, Atmos. Environ., 35, 3385-3394, doi:10.1016/S1352-2310(01)00138-8, 2001.
Wentzell, J. J.; Liggio, J.; Li, S.; Vlasenko, A. L.; Staebler, R. M.; Brook, J.; Lu, G.; Poitras, M.; Chan, T.
Application of zigbee for pollution monitoring caused by automobile exhaust gases
Gases emitted from automobile exhausts have been monitored using a gas sensor arrays. The information from the sensor array has been transmitted to a remote location by ZigBee wireless technology. Quantitative and qualitative analysis of gases has been conducted at the remote location by a computer. Programs have been developed in LabView and excel to display data and alarm conditions.
Halit Eren; Ahmed Al-Ghamdi; Jinhua Luo
Using engine exhaust gas as energy source for an absorption refrigeration system
This work presents an experimental study of an ammonia�water absorption refrigeration system using the exhaust of an internal combustion engine as energy source. The exhaust gas energy availability and the impact of the absorption refrigeration system on engine performance, exhaust emissions, and power economy are evaluated. A production automotive engine was tested in a bench test dynamometer, with the absorption
Andr� Aleixo Manzela; S�rgio Morais Hanriot; Luben Cabezas-G�mez; Jos� Ricardo Sodr�
Sensor for measuring the oxygen content in the exhaust gas of combustion engines and method thereof
An improved lambda sensor is disclosed for the measurement of the oxygen content in the exhaust gas of internal combustion engines in which the sensor element is provided with a gas permeable wrapping coated with a catalyst. The sensor delivers a clear well defined signal in the so-called rich exhaust gas, which makes possible a more precise adjustment of the
A. Bozon; E. Koberstein; H. Pletka; H. Voelker
Sensor for directly determining the exhaust gas recirculation rate�EGR sensor
Exhaust gas recirculation (EGR) is an effective means to reduce NOx emissions of internal combustion engines without increasing fuel consumption. Up to now, only complex procedures to determine the exhaust gas recirculation rate are available. Here, a novel sensor device is suggested that measures directly at one position and with only one single sensor device the concentration of a tracer
Ralf Moos; Burkhard Reetmeyer; Armin H�rland; Carsten Plog
Case study on thermoelectric generation system utilizing the exhaust gas of interal-combustion power plant
This paper discusses the effects of element length, installation of fins and exhaust gas flow rate on the power output and the conversion efficiency of a thermoelectric generation system using the exhaust gas of an internal combustion plant. The thermoelectric module consists of bismuth-tellurium based thermoelectric elements, electrodes, insulators, etc. A thermoelectric generation system consists of thermoelectric generation modules sandwiched
T. Furue; T. Hayashida; Y. Imaizumi; T. Inoue; K. Nagao; A. Nagai; I. Fujii; T. Sakurai
European regulations regarding exhaust gas emissions have constantly become more restricted in the last decades. Components of the exhaust gas after- treatment system and ECU strategies have become correspondingly more complicated in order to fulfil the prescribed limits. Development and calibration of the system thus requires more accurate tuning within the imposed constraints of costs and time to market. This
Vittorio Cioffi; Stefano Scala; Eduardo Sepe
Glutathione peroxidase inhibitory assay for electrophilic pollutants in diesel exhaust and tobacco smoke.
We developed a rapid kinetic bioassay demonstrating the inhibition of glutathione peroxidase 1 (GPx-1) by organic electrophilic pollutants, such as acrolein, crotonaldehyde, and p-benzoquinone, that are frequently found as components of tobacco smoke, diesel exhaust, and other combustion sources. In a complementary approach, we applied a high-resolution proton-transfer reaction time-of-flight mass spectrometer to monitor in real-time the generation of electrophilic volatile carbonyls in cigarette smoke. The new bioassay uses the important antioxidant selenoenzyme GPx-1, immobilized to 96-well microtiter plates, as a probe. The selenocysteine bearing subunits of the enzyme's catalytic site are viewed as cysteine analogues and are vulnerable to electrophilic attack by compounds with conjugated carbonyl systems. The immobilization of GPx-1 to microtiter plate wells enabled facile removal of excess reactive inhibitory compounds after incubation with electrophilic chemicals or aqueous extracts of air samples derived from different sources. The inhibitory response of cigarette smoke and diesel exhaust particle extracts were compared with chemical standards of a group of electrophilic carbonyls and the arylating p-benzoquinone. GPx-1 activity was directly inactivated by millimolar concentrations of highly reactive electrophilic chemicals (including acrolein, glyoxal, methylglyoxal, and p-benzoquinone) and extracts of diesel and cigarette smoke. We conclude that the potential of air pollutant components to generate oxidative stress may be, in part, a result of electrophile-derived covalent modifications of enzymes involved in the cytosolic antioxidant defense. PMID:22349402
Staimer, Norbert; Nguyen, Tran B; Nizkorodov, Sergey A; Delfino, Ralph J
Environment hazard estimates. [rocket exhaust gas diffusion models
Emission into the atmosphere of aerospace vehicle exhaust effluents and by-products is considered by using atmospheric diffusion models to calculate downwind concentrations and dosages from various engine and solid rocket booster (SRB) exhaust by-products. A major effort is being made to gather detailed data on the chemical reactions that take place between the exhaust effluents and the atmosphere. Basic diffusion estimation formulas consider normal exhaust releases, abnormal releases, leaks, and inadvertent spills. Cloud rise formulas for use in source identification are included and meteorological inputs covered.
Kaufman, J. W.; Stephens, J. B.; Hill, C. K.; Susko, M.
Method for controlling exhaust gas heat recovery systems in vehicles
A method of operating a vehicle including an engine, a transmission, an exhaust gas heat recovery (EGHR) heat exchanger, and an oil-to-water heat exchanger providing selective heat-exchange communication between the engine and transmission. The method includes controlling a two-way valve, which is configured to be set to one of an engine position and a transmission position. The engine position allows heat-exchange communication between the EGHR heat exchanger and the engine, but does not allow heat-exchange communication between the EGHR heat exchanger and the oil-to-water heat exchanger. The transmission position allows heat-exchange communication between the EGHR heat exchanger, the oil-to-water heat exchanger, and the engine. The method also includes monitoring an ambient air temperature and comparing the monitored ambient air temperature to a predetermined cold ambient temperature. If the monitored ambient air temperature is greater than the predetermined cold ambient temperature, the two-way valve is set to the transmission position.
Spohn, Brian L.; Claypole, George M.; Starr, Richard D
On the thermodynamics of waste heat recovery from internal combustion engine exhaust gas
The ideal internal combustion (IC) engine (Otto Cycle) efficiency ?IC= 1-(1/r)^(?-1) is only a function of engine compression ratio r=Vmax/Vmin and exhaust gas specific heat ratio ?= cP/cV. Typically r= 8, ?= 1.4, and ?IC= 56%. Unlike the Carnot Cycle where ?Carnot= 1-(TC/TH) for a heat engine operating between hot and cold heat reservoirs at TH and TC, respectively, ?IC is not a function of the exhaust gas temperature. Instead, the exhaust gas temperature depends only on the intake gas temperature (ambient), r, ?, cV, and the combustion energy. The ejected exhaust gas heat is thermally decoupled from the IC engine and conveyed via the exhaust system (manifold, pipe, muffler, etc.) to ambient, and the exhaust system is simply a heat engine that does no useful work. The maximum fraction of fuel energy that can be extracted from the exhaust gas stream as useful work is (1-?IC) x?Carnot= 32% for TH= 850 K (exhaust) and TC= 370 K (coolant). This waste heat can be recovered using a heat engine such as a thermoelectric generator (TEG) with ?TEG0 in the exhaust system. A combined IC engine and TEG system can generate net useful work from the exhaust gas waste heat with efficiency ?WH= (1-?IC) x?Carnot x?TEG, and this will increase the overall fuel efficiency of the total system. Recent improvements in TEGs yield ?TEG values approaching 15% giving a potential total waste heat conversion efficiency of ?WH= 4.6%, which translates into a fuel economy improvement approaching 5%.
Meisner, G. P.
An improved lambda sensor is disclosed for the measurement of the oxygen content in the exhaust gas of internal combustion engines in which the sensor element is provided with a gas permeable wrapping coated with a catalyst. The sensor delivers a clear well defined signal in the so-called rich exhaust gas, which makes possible a more precise adjustment of the fuel-air mixture fed to the internal combustion engine.
Bozon, A.; Koberstein, E.; Pletka, H.; Voelker, H.
Flow guiding and distributing devices on the exhaust side of stationary gas turbines
Following repeated cases of damage caused to exhaust silencers located directly beyond gas turbine diffusers, this paper reports on investigations carried out to determine possible remedies. In all instances, an uneven exhaust gas flow distribution was found. The company's innovative approach to the problem involved constructing a scale model of a complete gas turbine exhaust system and using it for flow simulation purposes. It was established for the first time that, subject to certain conditions, the results of tests conducted on a model can be applied to the actual turbine exhaust system. It is shown that when an unfavorable duct arrangement might produce an uneven exhaust flow, scale models are useful in the development of suitable flow-distributing devices.
Fleischer, F.; Koerner, C.; Mann, J. (G and H Montage GmbH, Ludwigshafen (DE))
Reduction of NO in the exhaust gas by reaction with N radicals
N atoms can serve as a reducing agent for NO in the exhaust gases from fossil fuel power plants. In order to investigate the reduction of NO, synthetic exhaust gas was plasma treated in a dielectric barrier discharge (DBD) (direct treatment) as well as treated by adding nitrogen atoms generated in a pure nitrogen DBD (remote treatment). A DBD with
F. Leipold; A. Fateev; Y. Kusano; B. Stenum; H. Bindslev
The effects of exhaust gas recirculation on diesel combustion and emissions
An investigation was conducted with the aim of identifying and quantifying the effects of exhaust gas recirculation (EGR) on diesel engine combustion and exhaust emissions. Five effects of EGR were identified and investigated experimentally: the reduction in oxygen supply to the engine, participation in the combustion process of carbon dioxide and water vapour present in the EGR, increase in the
N Ladommatos; S Abdelhalim; H Zhao
Under Sandia`s Laboratory Directed Research and Development (LDRD) program, novel acoustic wave-based sensors were explored for detecting gaseous chemical species in vehicle exhaust streams. The need exists for on-line, real-time monitors to continuously analyze the toxic exhaust gases -- nitrogen oxides (NOx), carbon monoxide (CO), and hydrocarbons (HC) -- for determining catalytic converter efficiency, documenting compliance to emission regulations, and
R. W. Cernosek; J. H. Small; P. S. Sawyer; J. R. Bigbie; M. T. Anderson
Method and apparatus of periodically obtaining accurate opacity monitor readings of an exhaust gas stream
This patent describes in an opacity monitor associated with an exhaust stack, the monitor having a transmitter and a receiving which cooperate to measure a quantity of particulate matter in an exhaust gas stream, a method of periodically obtaining opacity monitor readings. It comprises: shielding the monitor from the exhaust gas stream by placing two windows adjacent to the monitor, a first window being placed between the transmitter and the exhaust gas stream and a second window being placed between the receiver and the exhaust gas stream; cleaning at least one of the windows for a first predetermined time period by spraying a volatile nonflammable cleaning solvent onto the window by means of a sprayer intermittently operable during the first predetermined time period while wiping the window with a reciprocating wiper arm in resilient engagement therewith; then obtaining an opacity monitor reading by directing a light beam across the exhaust stack from the transmitter via the first window through the exhaust gas stream to the receiver via the second window; and alternately repeating the step of cleaning the window with the step of obtaining an opacity monitor reading.
Weaver, K.L.; Bellows, J.C.
40 CFR 86.1311-94 - Exhaust gas analytical system; CVS bag sample.
Exhaust Emissions Test Airesearch Aircraft Propulsion and Auxiliary Power Gas Turbine Engines.
The report describes the test setup, procedure, and analysis of exhaust emissions measurement conducted on 32 commercial gas turbine engines comprised of both on-board aircraft auxiliary power and aircraft propulsion production, overhaul, and development ...
Nicht limitierte Automobil-Abgaskomponenten. (Unregulated motor vehicle exhaust gas components).
The volume contains an overall presentation and assessment of the results of studies conducted by the Volkswagen company over the past 8 years in the field of legally unregulated motor vehicle exhaust gas components. Substantiated with numerous illustrati...
Gas separation process using membranes with permeate sweep to remove CO.sub.2 from gaseous fuel combustion exhaust
A gas separation process for treating exhaust gases from the combustion of gaseous fuels, and gaseous fuel combustion processes including such gas separation. The invention involves routing a first portion of the exhaust stream to a carbon dioxide capture step, while simultaneously flowing a second portion of the exhaust gas stream across the feed side of a membrane, flowing a sweep gas stream, usually air, across the permeate side, then passing the permeate/sweep gas back to the combustor.
Wijmans Johannes G. (Menlo Park, CA); Merkel, Timothy C. (Menlo Park, CA); Baker, Richard W. (Palo Alto, CA)
High-Octane Fuel from Refinery Exhaust Gas: Upgrading Refinery Off-Gas to High-Octane Alkylate
Broad Funding Opportunity Announcement Project: Exelus is developing a method to convert olefins from oil refinery exhaust gas into alkylate, a clean-burning, high-octane component of gasoline. Traditionally, olefins must be separated from exhaust before they can be converted into another source of useful fuel. Exelus� process uses catalysts that convert the olefin to alkylate without first separating it from the exhaust. The ability to turn up to 50% of exhaust directly into gasoline blends could result in an additional 46 million gallons of gasoline in the U.S. each year.
Control method for turbocharged diesel engines having exhaust gas recirculation
A method of controlling the airflow into a compression ignition engine having an EGR and a VGT. The control strategy includes the steps of generating desired EGR and VGT turbine mass flow rates as a function of the desired and measured compressor mass airflow values and exhaust manifold pressure values. The desired compressor mass airflow and exhaust manifold pressure values are generated as a function of the operator-requested fueling rate and engine speed. The EGR and VGT turbine mass flow rates are then inverted to corresponding EGR and VGT actuator positions to achieve the desired compressor mass airflow rate and exhaust manifold pressure. The control strategy also includes a method of estimating the intake manifold pressure used in generating the EGR valve and VGT turbine positions.
Kolmanovsky, Ilya V. (Ypsilanti, MI); Jankovic, Mrdjan J (Birmingham, MI); Jankovic, Miroslava (Birmingham, MI)
HPLC analysis of aldehydes in automobile exhaust gas: Comparison of exhaust odor and irritation in different types of gasoline and diesel engines
This study investigated high performance liquid chromatography (HPLC) to identify and measure aldehydes from automobile exhaust gas. Four aldehydes: formaldehyde (HCHO), acetaldehyde (CH3CHO), acrolein (H2CCHCHO) and propionaldehyde (CH3CH2CHO) and one ketone, acetone (CH3)2CO are separated. The other higher aldehydes in exhaust gas are very small and cannot be separated. A new method of gas sampling, hereafter called bag sampling in
Murari Mohon Roy
Use of exhaust gas as sweep flow to enhance air separation membrane performance
An intake air separation system for an internal combustion engine is provided with purge gas or sweep flow on the permeate side of separation membranes in the air separation device. Exhaust gas from the engine is used as a purge gas flow, to increase oxygen flux in the separation device without increasing the nitrogen flux.
Dutart, Charles H. (Washington, IL); Choi, Cathy Y. (Morton, IL)
Diesel engines play an important role in the United States economy for power generation and transportation. However, NOx and soot emissions from both stationary and mobile diesel engines are a major contributor to air pollution. Many engine modifications and exhaust-after-t...
Test Program for High Efficiency Gas Turbine Exhaust Diffuser.
This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of strutlets to control stalls on a model diffuser strut. Strutlet...
T. R. Norris
FTIR Determination of Pollutants in Automobile Exhaust: An Environmental Chemistry Experiment Comparing Cold-Start and Warm-Engine Conditions
An experiment developed from the Advanced Integrated Environmental Laboratory illustrates the differences in automobile exhaust before and after the engine is warmed, using gas-phase Fourier transform infrared spectroscopy (FTIR). The apparatus consists of an Avatar 360 FTIR spectrometer from Nicolet fitted with a variable path length gas cell,�
Medhurst, Laura L.
Surface gas pollutants in Lhasa, a highland city of Tibet: current levels and pollution implications
Through several years of development, the city of Lhasa has become one of the most populated and urbanized areas on the highest plateau in the world. In the process of urbanization, current and potential air quality issues have been gradually concerned. To investigate the current status of air pollution in Lhasa, various gas pollutants including NOx, CO, SO2 and O3 were continuously measured from June 2012 to May 2013 at an urban site (29.40� N, 91.08� E, 3650 m a.s.l.). The seasonal variations of primary gas pollutants exhibited a peak from November to January with a large variability. High concentrations of primary trace gases almost exclusively occurred under low wind speed and showed no distinct dependence on wind direction, implying local urban emissions to be predominant. A comparison of NO2, CO and SO2 concentrations in summer between 1998 and 2012 indicated a significant increase in emissions of these gas pollutants and a change in their intercorrelations, as a result of a substantial growth in the demand of energy consumption using fossil fuels instead of previously widely used biofuels. The pronounced diurnal double peaks of primary trace gases in all seasons suggested automobile exhaust to be a major emission source in Lhasa. The secondary gas pollutant O3 displayed an average diurnal cycle of a shallow flat peak for about 4-5 h in the afternoon and a minimum in the early morning. Nighttime O3 was sometimes completely consumed by the high level of NOx. Seasonally, the variations of O3 concentrations displayed a low valley in winter and a peak in spring. In autumn and winter, transport largely contributed to the observed O3 concentrations, given its dependence on wind speed and wind direction, while in spring and summer photochemistry played an important role. A more efficient buildup of O3 concentrations in the morning and a higher peak in the afternoon was found in summer 2012 than in 1998. An enhancement in O3 concentrations would be expected in the future and more attention should be given to O3 photochemistry in response to increasing precursor emissions in this area.
Ran, L.; Lin, W. L.; Deji, Y. Z.; La, B.; Tsering, P. M.; Xu, X. B.; Wang, W.
Suicide by carbon monoxide from car exhaust-gas in Denmark 1995-1999.
In the period 1995-1999 there were 388 car exhaust-gas suicides in Denmark. Of these 343 (88.4%) were men and 45 (11.6%) were women, the average age being 47 years. The car exhaust-gas suicides made up 9.3% of all suicides in Denmark in the period. The corresponding rate was 11.7% for men and 3.7% for women. In rural areas a larger part of all suicides were committed with car exhaust-gas compared to the more densely populated areas. Mental disease was diagnosed in 124 (32.0%) cases. A suicide note was found in 165 (42.5%) cases. A hose was fitted to the exhaust pipe in 334 (86.1%) cases. Of these the 234 (60.3%) occurred outside, typically in a forest area, while 76 (19.6%) occurred in a closed garage. All the 54 (13.9%) cases with no hose fitted to the exhaust pipe occurred in a garage. Seven (1.8%) victims were found in a burning or burnt-out car, where the following investigation revealed that it was actually a car exhaust-gas suicide. Carboxyhemoglobin was measured in 26 (6.7%) victims. In two of these victims no carboxyhemoglobin was found, as they had survived for some time after the poisoning. The average saturation of the remaining victims was 67%, the lowest saturation being 20% and the highest being 84%. In the period 1969-1987 the number of car exhaust-gas suicides in Denmark increased from 50 to approximately 190 per year and the rate of car exhaust-gas suicides compared to all suicides increased from approximately 5% to approximately 13%. In 1987-1999 these figures decreased from approximately 190 to 63 per year and from 13% to approximately 8%. During these 30 years the number of passenger cars in Denmark doubled, which explains the increase in car exhaust-gas suicides during 1969-1987. A possible explanation for the decrease in 1987-1999 is the introduction of the catalytic converter, which was made mandatory in 1990. We anticipate that car exhaust-gas suicides will continue to decrease in numbers, as more cars are equipped with catalytic converters. PMID:16310328
Thomsen, Asser H; Gregersen, Markil
Diesel emission reduction using internal exhaust gas recirculation
A method for controlling combustion in a direct-injection diesel engine includes monitoring a crankshaft rotational position of a cylinder of the engine, monitoring an engine load, determining an intake stroke within the cylinder based upon the crankshaft rotational position, and when the engine load is less than a threshold engine load, opening an exhaust valve for the cylinder during a portion of the intake stroke.
He, Xin (Denver, CO); Durrett, Russell P. (Bloomfield Hills, MI)
An experimental investigation of rectangular exhaust-gas ejectors applicable for engine cooling
An experimental investigation of rectangular exhaust-gas ejector pumps was conducted to provide data that would serve as a guide to the design of ejector applications for aircraft engines with marginal cooling. The pumping characteristics of rectangular ejectors actuated by the exhaust of a single-cylinder aircraft engine were determined for a range of ejector mixing-section area from 20 to 50 square inches, over-all length from 12 to 42 inches, aspect ratio from 1 to 5, diffusing exit area from 20 to 81 square inches, and exhaust-nozzle aspect ratio from 1 to 42.
Manganiello, Eugene J; Bogatsky, Donald
Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity
A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.
Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)
A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime (about 40 ps), high frequency (about 5G hz), high power bursts of low-duty factor microwaves sufficient to generate a dielectric barrier discharge and passing a gas to treated through the discharge so as to cause dissociative reduction of the exhaust gases. The invention also includes a reactor for generating the non-thermal plasma.
Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Upsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)
Low-pressure-ratio regenerative exhaust-heated gas turbine. Final report
Oxygen Smelting of Copper Concentrate With Exhaust SO2 Gas Recycling
In the conventional copper smelting process, the concentrate is usually oxidized by air, and heat is supplied by the combustion of fuel. Considerable dust and heat losses, due to the large quantity of exhaust gas, are inevitable. The use of oxygen greatly decreases such losses, but the copper matte grade is limited to around 50% to keep the furnace temperature at an optimum level. An oxygen smelting process, with exhaust SO2 recycling, is proposed based upon material and heat balance calculations. When 60% Cu matte is produced, the participating amounts of heat and gas are around 62% and 28% (14% if final gas is considered) of those of the conventional process. A considerable decrease in capital and operating costs can be expected when considering a new smelter. Because a small volume of high-strength SO2 exhaust gas is produced, this process has large flexibility with respect to sulfur by-products and offers a major advantage in environmentally sensitive locations.
Yazawa, Akira; Tozawa, Kazuteru
Exhaust Gas Modeling Effects on Hypersonic Powered Simulation at Mach 10
A numerical study was performed to investigate the accuracy and validity of cold-gas simulation of actual hot scramjet exhaust within a Mach 10 free stream over a representative single-stage-to-orbit airbreathing configuration. In particular, exhausts of various noncombusting chemistry models were studied to characterize their effects on the vehicle aftbody performance and the plume flow field definition. Two approximations of the hot scramjet combustion products were utilized to determine the requirement for expensive, multi-species numerical modeling, and to establish a baseline for the validation of cold-gas simulation. Cold-gas simulation at Mach 10 is shown to be a viable technique using an appropriate thermally perfect gas mixture for reproducing hot scramjet exhaust effects.
Tatum, Kenneth E.; Huebner, Lawrence D.
Experimental observation of carbon dioxide reduction in exhaust gas from hydrocarbon fuel burning
A high-negative voltage at the cathode initiates a dark discharge, resulting in a reduction of the carbon dioxide concentration in exhaust gas from the burning of hydrocarbon fuel. An experiment indicated that nearly 44% of the carbon dioxide in exhaust gas disappears after a high-voltage application to the cathode. The energy needed for the endothermic reaction of the carbon dioxide dissociation corresponding to this concentration reduction is provided mainly by the internal energy reduction of the discharge gas, which is nearly 20 times the electrical energy for electron emission.
Uhm, Han S. [Department of Molecular Science and Technology, Ajou University, Suwon 443-749 (Korea, Republic of); Kim, Chul H. [S and P Energy Co. Ltd., 286-10 Chujari, Opo-Eup, Gwangju-Si 464-909 (Korea, Republic of)
Exhaust recirculation
An exhaust gas recirculation system for the reduction of nitrogen oxide emissions from internal combustion engine exhaust is described that is uncomplicated by moving parts, thus avoiding problems associated with prior-art recirculation systems. The system also results in preheating and improved mixing of the fuel-air mixture in the inlet header. A recycling duct receives the exhaust gases at a restricted
An exhaust gas recirculation system for the reduction of nitrogen oxides in automobile exhaust is described that provides for the reduction of recirculation during engine idling without the prior-art complexities of moving parts. The system also achieves preheating and improved mixing and carburetion of the fuel-air mixture in the inlet header. Exhaust gases are recycled by means of a swirl
Workshop on an Assessment of Gas-Side Fouling in Fossil Fuel Exhaust Environments
The state of the art of gas side fouling in fossil fuel exhaust environments was assessed. Heat recovery applications were emphasized. The deleterious effects of gas side fouling including increased energy consumption, increased material losses, and loss of production were identified.
Marner, W. J. (editor); Webb, R. L. (editor)
A ceramic heat exchanger for exhaust fired gas turbine power cycles
Until recently, combustion of solid fuels such as forest product residues, municipal waste, or coal in gas turbine power cycles has been limited by the corrosive action of the combustion products. A heat exchanger which can operate in this corrosive environment has been developed, making the exhaust fired gas turbine an economically viable power source. This heat exchanger is fabricated
I. G. Most; K. G. Hagen
The document describes assembly, operation, and maintenance of the Exhaust Gas Recycle (EGR) sampling system. The design of the sampling train allows the operator to maintain a constant flow rate through an inertial sampler while the gas flow rate into the sampling nozzle is adju...
Study on the correction model of aero-engine exhaust gas temperature
Therefore, the measure gas path parameters must be standardized into the value under the external environment which was same to baseline, the process was called performance corrected process. The standardized model of aero-engine exhaust gas temperature (EGT) was analyzed in this paper, and the new standardized model based on core function different from the experimental test bed of aircraft maintenance
Zhi-quan Cui; Lin; Shi-sheng Zhong; Ti-chun Wang
Exhaust gas recirculation control method and apparatus for internal combustion engine
An exhaust gas recirculation control method is described for operating an exhaust gas recirculation control device including a needle valve provided in an exhaust gas recirculation passage for setting an effective diameter of the passage, a position sensor for providing a signal representing a position of the needle valve, and a negative pressure motor for positioning the needle valve. The method comprises: setting a target value for the needle valve according to predetermined operating conditions of the internal combustion engine; measuring a positional deviation between the target value and an actual position of the needle valve as represented by the signal provided by the position sensor; and driving the negative pressure motor with only a single drive pulse having a time width corresponding to the measured positional deviation. An exhaust gas recirculation control apparatus is described for operating an exhaust gas recirculation control device. The apparatus comprises: means for setting a target value for the needle valve according to predetermined operating conditions of the internal combustion engine; and means for measuring a positional deviation between the target value and an actual position of the needle valve as represented by the signal provided by the position sensor.
Tsutsumi, K.
An Experimental Investigation of an Exhaust-gas-to-air Heat Exchanger for Use on Jet-stack-equipped Engines
Tests were made to determine the loss in exhaust-jet thrust and engine power resulting from the insertion of an exhaust-gas-to-air heat exchanger in a jet-type exhaust stack of an aircraft engine. The thermal performance of the heat exchanger was also determined.
Stalder, Jackson R; Spies, Ray J , Jr
Intake manifold for internal combustion engine having exhaust gas recirculation system
An intake manifold is described of an internal combustion engine which has an exhaust gas recirculation system. It introduces a part of exhaust gas from an exhaust passage through an EGR gas supply passage into the intake manifold. The intake manifold is provided with an EGR gas outlet opened thereto and connected to the EGR gas supply passage. The EGR gas outlet is located in an upper section of an interior of the intake manifold. A part of the EGR gas supply passage, in the vicinity of the EGR gas outlet extends transversely along a side-to-top wall of the intake manifold. The part of EGR gas passage defines at an opposite side thereof an inclined inner wall along the side-to-top wall of the intake manifold, in a transverse cross-section of the intake manifold. The inclined inner wall has its top portion directed downward to define the EGR gas outlet, so that the EGR gas outlet is defined below an inner surface of the top wall of the inner intake manifold.
Yokoi, T.; Takeya, E.; Hattori, K.; Abe, K.; Osawa, H.
40 CFR 86.1509 - Exhaust gas sampling system.
...Heavy-Duty Engines, New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum Gas-Fueled Diesel-Cycle Heavy-Duty Engines...Light-Duty Trucks, and New Methanol-Fueled Natural Gas-Fueled, and Liquefied Petroleum...
40 CFR 86.1511 - Exhaust gas analysis system.
Exhaust gas purifier with resistant circumferential sealing member between monolith catalyst and casing
A monolithic catalytic exhaust gas purifier is described for an internal combustion engine. The purifier includes a cylindrical sheet metal casing having a longitudinal axis, a first end with an inlet, and a second end opposite the first end with an outlet for respectively introducing exhaust gas into and discharging exhaust gas from the casing. The casing has a flattened cross section transverse to the axis with a minimum cross dimension in one direction and a maximum cross dimension perpendicular to the one direction, a monolithic catalyst housed within the casing, and a supporting and sealing member of heat-insulating resilient material and an outer peripheral surface of the catalyst facing the flattened cylindrical wall of the casing. The supporting and sealing member exists completely around the outer peripheral circumference of the catalyst.
Shimozi, K.; Teshima, H.
Performance of blowdown turbine driven by exhaust gas of nine-cylinder radial engine
An investigation was made of an exhaust-gas turbine having four separate nozzle boxes each covering a 90 degree arc of the nozzle diaphragm and each connected to a pair of adjacent cylinders of a nine-cylinder radial engine. This type of turbine has been called a "blowdown" turbine because it recovers the kinetic energy developed in the exhaust stacks during the blowdown period, that is the first part of the exhaust process when the piston of the reciprocating engine is nearly stationary. The purpose of the investigation was to determine whether the blow turbine could develop appreciable power without imposing any large loss in engine power arising from restriction of the engine exhaust by the turbine.
Turner, L Richard; Desmon, Leland G
Exhaust Gas Recirculation for Retrofit NOx Control on Natural Gas Engines. Topical Report January-April 1988,
Data on exhaust gas recirculation obtained from Tenneco Gas Transportation Company were reviewed and analyzed, and a basic EGR system design and cost estimate were developed. EGR can provide practical NOx reductions of up to 50 percent in 2-cycle natural ...
C. M. Urban
Groups of male and female mice inhaled either clean air, 100 ppm carbon monoxide, or light-irradiated and nonirridiated automotive exhaust containing nominally 25, 50, 75, or 100 ppm carbon monoxide in three tests with exposure lasting from 4 to 7 days. Exhaust from a factory or ...
Regenerable diesel exhaust filter
An exhaust gas filter assembly is described for removing particulates from the exhaust gas of an engine, comprising, in combination: a housing having an inlet pipe and an outlet pipe and defining an exhaust gas flow path between the inlet pipe and the outlet pipe, the inlet pipe being coupled to the engine to receive exhaust gas therefrom and the
Exhaust Emissions from Seven LP Gas Powered Vehicles.
An evaluation was undertaken of seven LP gas powered, standard sized American cars. The cars were equipped with V-8 engines, automatic transmissions and Algas Industries dual fuel carburetion systems. Each car was tested according to the proposed 1972 Fed...
H. A. Ashby
A program was conducted to chemically characterize particulate emissions from a current technology, high population, gas turbine engine. Attention was focused on polynuclear aromatic compounds, phenols, nitrosamines and total organics. Polynuclear aromatic hydrocarbons (PAH) were...
Fast exhaust channel optical absorption method and apparatus to study the gas exchange in large diesel engines
An optical absorption spectroscopic method and apparatus with shorter than 1 ms response time have been used to study the gas exchange processes in realistic conditions for a single cylinder of a large diesel engine. The method is based on measuring the differential line-of-sight optical uv absorption of the exhaust-gas-contained SO2 as a function of time in the exhaust port area just after the exhaust valves. The optical absorption by SO2 is determined from light transmission measurements at 280 and 340 nm performed through optical probes installed into the exhaust channel wall. The method has been applied to a continuously fired, large, medium speed production-line-type diesel engine with 990 kW rated power. The test engine was operated with standard light fuel oil (MDO Termoshell) and with light fuel oil treated with a sulfur additive {Di-Tert-Butyldisulfid [(CH3)3C]2S2}. The latter was to improve the optical absorption signals without increasing the fouling of the exhaust channel optical probes as in the case of heavier fuel oil qualities. In the reported case of a four-stroke diesel engine measurement results show that the method can provide time-resolved information of the SO2 density in the exhaust channel and thus give information on the single-cylinder gas exchange. During the inlet and exhaust valve overlap period the moment of fresh air entering into the measurement volume can be detected. If independent exhaust gas temperature and pressure data are available, the absorption measurements can readily be used for determining the burnt gas fraction in the exhaust channel. In this work the possibility of using the optical absorption measurement to determine the instaneous exhaust gas temperature was studied. Based on known fuel properties and conventional averaged SO2 measurements from the exhaust channel a known concentration of SO2 was assumed in the exhaust gas after the exhaust valves opening and before the inlet and exhaust valves overlap period. Together with an exhaust gas pressure measurement the optical absorption signal was used to determine the instaneous exhaust gas temperature. Due to the minimal modifications needed by the engine for optical access, and continuously fired operation with relevant power levels and realistic fuel qualities, this measurement method, with some further development, can be useful to obtain time-resolved data from the exhaust channel of real production-line-type diesel engines.
Vattulainen, J.; Hernberg, R.; Hattar, C.; Gros, S.
Workshop on an Assessment of Gas-Side Fouling in Fossil-Fuel-Exhaust Environments.
A workshop has been carried out to assess the state-of-the-art of gas-side fouling in fossil fuel exhaust environments. Special emphasis was placed on heat recovery applications. For purposes of discussion, the workshop was organized into four different g...
R. L. Webb W. J. Marner
Designing small gas turbine engines for low noise and clean exhaust
Preliminary results of design studies involving the use of small gas turbine engines to reduce noise and exhaust emissions from aircraft are reviewed. Comparisons of reciprocating engines with small turboprop engines indicate lower carbon monoxide and hydrocarbon emissions for the latter engine type at all power settings. The piston engines show somewhat lower nitrogen oxide production above 20 percent power,
H. C. Eatock; J. C. Plucinsky; J. A. Saintsbury
Improvement of NOx Reduction Efficiency in Diesel Emission Using Nonthermal Plasma - Exhaust Gas Recirculation Combined Aftertreatment
Atmospheric-pressure nonequilibrium nonthermal plasma (NTP) hybrid exhaust gas aftertreatment systems have been developed by the authors without using precious metal catalysts and harmful ammonia, etc. Two types of new environmental protection systems (a dry system and a wet system), which enable to produce ultra low CO2, PM (Particulate Matter), NOx emissions, fuel consumption and low cost, are investigated for diesel
Masaaki OKUBO; Takuya KUWAHARA; Yohei KANNAKA; Tomoyuki KUROKI; Keiichiro YOSHIDA
Dynamic Instabilities in Spark-Ignited Combustion Engines with High Exhaust Gas Recirculation.
We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global...
C. E. A. Finney C. S. Dawov
A particulate sampling train has been constructed which satisfies the conflicting requirements of isokinetic sample extraction and constant flowrate through an inertial sizing device. Its design allows a variable fraction of the filtered exhaust gas to be added to the sample upst...
System acceptance and operability test report for the RMCS exhauster C on flammable gas tanks
This test report documents the completion of acceptance and operability testing of the rotary mode core sampling (RMCS) exhauster C, as modified for use as a major stack (as defined by the Washington State Department of Health) on flammable gas tanks.
Waldo, E.J.
Measurement of Polycyclic Aromatic Hydrocarbons in Diesel Exhaust Gas by a Part Flow Process.
A new process for the quantitative analysis of polycyclic aromatic hydrocarbons is described in this report, where the samples are collected by extracting a part flow from the diluted exhaust gas. The important advantage of this method is that apart from ...
A. Hartung J. Kraft J. Schulze H. Hartwig K. H. Lies
Tables of the Thermodynamic Properties of Air and the Exhaust Gas from a Turbine Engine.
Thermodynamic properties of air and the exhaust gas from a turbine engine (C(n)H(1.95n))/Air System) are presented in tabular form. The properties presented air enthalpy (h), entropy (s), and specific heat at constant pressure (cp). The properties of air ...
J. M. Pelton K. L. Hannah
Catalytic exhaust gas fuel reforming for diesel engines�effects of water addition on hydrogen production and fuel conversion efficiency
Previous work in our laboratory has shown that the exhaust gas assisted fuel reforming process has the potential to provide a solution to the diesel engine exhaust emission problems. When simulated reformer product gas rich in hydrogen is fed to the engine, a reduction of both NOx and smoke emissions can be achieved. In this paper, the optimisation of the
A. Tsolakis; A. Megaritis
Characterization and control of exhaust gas from diesel engine firing coal-water mixture
Exhaust from the GE-TS single cylinder diesel engine, fitted with hardened metal, and diamond-tipped metal fuel injection nozzles, and firing coal-water mixture (CWM) has been characterized with respect to gas composition, particulate size distribution, and particulate filtration characteristics. The measured flue gas compositions are roughly in keeping with results from combustion calculations. The time variations of the hydrocarbon, CO, and NO{sub x} concentrations are also understood in terms of known reaction mechanisms.
Samuel, E.A.; Gal, E.; Mengel, M.; Arnold, M.
Exhaust from the GE-TS single cylinder diesel engine, fitted with hardened metal, and diamond-tipped metal fuel injection nozzles, and firing coal-water mixture (CWM) has been characterized with respect to gas composition, particulate size distribution, and particulate filtration characteristics. The measured flue gas compositions are roughly in keeping with results from combustion calculations. The time variations of the hydrocarbon, CO, and NO[sub x] concentrations are also understood in terms of known reaction mechanisms.
The Effect of Exhaust Gas on the Performance in Certain Psychological Tests
Six volunteers were exposed to 200 to 400 ppM CO (+-20 ppM) in exhaust gas for 3.5 to 6 hr per day on a number of days. COHb was elevated to 25 to 35%. They were subjected to tests including: steadiness, rapid tapping, handgrip strength, code substitution, arithmetic, location memory, and flashing light location response. The effect of the gas
Roy M. Dorcus; G. E. Weigand
Carbon dioxide capture and use: organic synthesis using carbon dioxide from exhaust gas.
A carbon capture and use (CCU) strategy was applied to organic synthesis. Carbon dioxide (CO2) captured directly from exhaust gas was used for organic transformations as efficiently as hyper-pure CO2 gas from a commercial source, even for highly air- and moisture-sensitive reactions. The CO2 capturing aqueous ethanolamine solution could be recycled continuously without any diminished reaction efficiency. PMID:24307628
Kim, Seung Hyo; Kim, Kwang Hee; Hong, Soon Hyeok
Identification, structure elucidation, and synthesis of volatile compounds in the exhaust gas of food factories
Our investigations deal with the identification and synthesis of volatile, odoriferous compounds contained in the exhaust gas of food factories and on the biodegradation of alkylpyrazines.Collection of odour emissions samples was performed with a gas sampler equipped with filter tubes containing the styrene-polymer SuperQ. After elution with solvents of different polarity, the extracts were analysed by GC\\/MS and chemical microreactions.
S. Nagorny; W. Francke
Method and apparatus to selectively reduce NO.sub.x in an exhaust gas feedstream
A method and apparatus are described to selectively reduce NO.sub.x emissions of an internal combustion engine. An exhaust aftertreatment system includes an injection device operative to dispense a hydrocarbon reductant upstream of a silver-alumina catalytic reactor device. A control system determines a NO.sub.x concentration and hydrocarbon/NOx ratio based upon selected parameters of the exhaust gas feedstream and dispenses hydrocarbon reductant during lean engine operation. Included is a method to control elements of the feedstream during lean operation. The hydrocarbon reductant may include engine fuel.
Schmieg, Steven J. (Troy, MI); Blint, Richard J. (Shelby Township, MI); Den, Ling (Sterling Heights, MI); Viola, Michael B. (Macomb Township, MI); Lee, Jong-Hwan (Rochester Hills, MI)
Exhaust emission control apparatus
This patent describes an exhaust control apparatus for muffling noise and treating odors and pollutants, including solid particulate and gases in the exhaust of an internal combustion engine. It comprises an exhaust inlet tube for receiving the exhaust generated by an internal combustion engine; a cyclone barrier concentrically surrounding the exhaust inlet tube, a ring cavity between the cyclone tube and exhaust inlet tube defining a cyclone chamber in which the exhaust is treated; means for directing the exhaust from the exhaust inlet tube into the cyclone chamber; electrode means having small openings through which the exhaust passes to enter the cyclone chamber, the electrode means generating electrostatic forces which charge the solid particulate in the exhaust, ionize air and generate ozone in the cyclone chamber near the electrode; means for injecting air into the cyclone chamber causing centrifugal flow of the air and the exhausted within the cyclone chamber and increasing a dwell time of the exhaust within the cyclone chamber.
Eng, J.W.
Thermoelectric Power Generation System for Future Hybrid Vehicles Using Hot Exhaust Gas
The present experimental and computational study investigates a new exhaust gas waste heat recovery system for hybrid vehicles, using a thermoelectric module (TEM) and heat pipes to produce electric power. It proposes a new thermoelectric generation (TEG) system, working with heat pipes to produce electricity from a limited hot surface area. The current TEG system is directly connected to the exhaust pipe, and the amount of electricity generated by the TEMs is directly proportional to their heated area. Current exhaust pipes fail to offer a sufficiently large hot surface area for the high-efficiency waste heat recovery required. To overcome this, a new TEG system has been designed to have an enlarged hot surface area by the addition of ten heat pipes, which act as highly efficient heat transfer devices and can transmit the heat to many TEMs. As designed, this new waste heat recovery system produces a maximum 350 W when the hot exhaust gas heats the evaporator surface of the heat pipe to 170�C; this promises great possibilities for application of this technology in future energy-efficient hybrid vehicles.
Kim, Sun-Kook; Won, Byeong-Cheol; Rhi, Seok-Ho; Kim, Shi-Ho; Yoo, Jeong-Ho; Jang, Ju-Chan
Estimation and validation of PM 2.5/PM 10 exhaust and non-exhaust emission factors for practical street pollution modelling
In order to carry out efficient traffic and air quality management, validated models and PM emission estimates are needed. This paper compares current available emission factor estimates for PM 10 and PM 2.5 from emission databases and different emission models, and validates these against eight high quality street pollution measurements in Denmark, Sweden, Germany, Finland and Austria. The data sets show large variation of the PM concentration and emission factors with season and with location. Consistently at all roads the PM 10 and PM 2.5 emission factors are lower in the summer month than the rest of the year. For example, PM 10 emission factors are in average 5-45% lower during the month 6-10 compared to the annual average. The range of observed total emission factors (including non-exhaust emissions) for the different sites during summer conditions are 80-130 mg km -1 for PM 10, 30-60 mg km -1 for PM 2.5 and 20-50 mg km -1 for the exhaust emissions. We present two different strategies regarding modelling of PM emissions: (1) For Nordic conditions with strong seasonal variations due to studded tyres and the use of sand/salt as anti-skid treatment a time varying emission model is needed. An empirical model accounting for these Nordic conditions was previously developed in Sweden. (2) For other roads with a less pronounced seasonal variation (e.g. in Denmark, Germany, Austria) methods using a constant emission factor maybe appropriate. Two models are presented here. Further, we apply the different emission models to data sets outside the original countries. For example, we apply the "Swedish" model for two streets without studded tyre usage and the "German" model for Nordic data sets. The "Swedish" empirical model performs best for streets with studded tyre use, but was not able to improve the correlation versus measurements in comparison to using constant emission factors for the Danish side. The "German" method performed well for the streets without clear seasonal variation and reproduces the summer conditions for streets with pronounced seasonal variation. However, the seasonal variation of PM emission factors can be important even for countries not using studded tyres, e.g. in areas with cold weather and snow events using sand and de-icing materials. Here a constant emission factor probably will under-estimate the 90-percentiles and therefore a time varying emission model need to be used or developed for such areas. All emission factor models consistently indicate that a large part (about 50-85% depending on the location) of the total PM 10 emissions originates from non-exhaust emissions. This implies that reduction measures for the exhaust part of the vehicle emissions will only have a limited effect on ambient PM 10 levels.
Ketzel, Matthias; Omstedt, Gunnar; Johansson, Christer; D�ring, Ingo; Pohjola, Mia; Oettl, Dietmar; Gidhagen, Lars; W�hlin, Peter; Lohmeyer, Achim; Haakana, Mervi; Berkowicz, Ruwim
Cytotoxicity of the exhaust gas from a thermal reactor of MSWI baghouse ash.
Baghouse ash from municipal solid waste incineration (MSWI) plant was heated from 25 degrees C to 800 degrees C under nitrogen in a fixed-bed reactor. The exhaust gas was passed sequentially through water, acetone and cyclohexane. The cytotoxicity testing of the three adsorbates was done with the MRC-5 cell line and the percentage cell survival was determined by 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenol)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) analysis. The highest level of toxicity of the exhaust gas was observed at 500 degrees C. The total cytotoxicity of the three adsorbates at any treatment temperature was found to be a function of the sum of organic carbon (TOC), inorganic carbon (IC) and molecular chlorine (Cl(2)), of which, molecular chlorine was quantitatively the greatest. PMID:17585993
Huang, Wu-Jang; Shue, Meei-Fang
Method of and apparatus for recovering exhaust gas energy of internal combustion engine
A method is described of recovering exhaust gas energy of an internal combustion engine of a type which incorporates a turbine generator driven by the exhaust gas energy of the internal combustion engine and in which driving power of a motor driven by power generated by the generator is added to driving power of the internal combustion engine, characterized in that the method includes a control device for controlling an output torque of the motor in different forms at low and high speed areas with in a variable control range of a rotation speed of the internal combustion engine, and that the motor is operated with constant torque characteristics at the low speed area and with reduced torque characteristics at the high speed area.
Kobayashi, H.
Apparatus for measuring rotor exhaust gas bulk temperature in a combustion turbine and method therefore
Apparatus is described for measuring rotor exhaust gas bulk total temperature in a combustion turbine which includes first and last stages of rotating turbine blades comprising: optical pyrometer means for measuring the circumferentially total gas averaged temperature relative to said last stage turbine blades at a plurality of common radial points from the turbine hub to tip where said optical pyrometer means includes a single optical pyrometer having a line of sight along with means for rotating such pyrometer around an axis of rotation, with the pyrometer being tilted from said axis so that the line of sight of said pyrometer rotates around said axis thereby providing a radial traverse of said last stage turbine blades; means for calculating said rotor exhaust bulk total temperature relative to said last stage blades by flow weight averaging said measured temperatures of said radial points.
Allen, J.M.
Diagnosing system for an exhaust gas recirculation system of an automotive engine
This patent describes a diagnosing system for an exhaust gas recirculation system having an EGR passage communicating an exhaust pipe of an engine with an intake passage of the engine, an EGR valve provided in the EGR passage, control means for opening the EGR valve in accordance with enigne operating conditions comprising: first means for detecting flow rate of recirculated gas in the EGR passage and for producing an actual EGR rate signal dependent on the flow rate; second means for producing a desired EGR rate signal including an allowable range in accordance with engine operating conditions; and third means responsive to the actual EGR rate signal and the desired EGR rate signal for producing a trouble signal as an alarm signal when the actual EGR rate signal is out of the allowable range.
Tamura, I.
The paper discusses two tracer gas studies, to quantify the extent to which exhaust gases from indoor radon reduction systems are re-entrained into pitched-roof houses (exposing persons indoors), and the manner in which the exhausts disperse outdoors (exposing persons outside the...
Study of low emission homogeneous charge compression ignition (HCCI) engine using combined internal and external exhaust gas recirculation (EGR)
This paper focuses on the effects of internal and cooled external exhaust gas recirculation (EGR) on the combustion and emission performance of diesel fuel homogeneous charge compression ignition (HCCI). The use of fuel injection before the top center (TC) of an exhaust stroke and the negative valve overlap (NVO) to form the homogeneous mixture achieves low NOx and smoke emissions
Lei Shi; Yi Cui; Kangyao Deng; Haiyong Peng; Yuanyuan Chen
Real-time measurement of nitrogen dioxide in vehicle exhaust gas by mid-infrared cavity ring-down spectroscopy
The application of pulsed cavity ring-down spectroscopy (CRDS) was demonstrated for the measurement of nitrogen dioxide (NO2) in automotive exhaust gas. The transition of the ? 3 vibrational band assigned to the antisymmetric stretching mode of NO2 was probed with a thermoelectrically cooled, pulsed, mid-infrared, distributed feedback, quantum cascade laser (QCL) at 6.13 ?m. The measurement of NO2 in the exhaust gas from two diesel vehicles equipped with different aftertreatment devices was demonstrated using a CRDS-based NO2 sensor, which employs a HEPA filter and a membrane gas dryer to remove interference from water as well as particulates in the exhaust gas. Stable and sensitive measurement of NO2 in the exhaust gas was achieved for more than 30 minutes with a time resolution of 1 s.
Yamamoto, Y.; Sumizawa, H.; Yamada, H.; Tonokura, K.
Cytotoxicity of the exhaust gas from a thermal reactor of MSWI baghouse ash
Baghouse ash from municipal solid waste incineration (MSWI) plant was heated from 25�C to 800�C under nitrogen in a fixed-bed reactor. The exhaust gas was passed sequentially through water, acetone and cyclohexane. The cytotoxicity testing of the three adsorbates was done with the MRC-5 cell line and the percentage cell survival was determined by 3-(4,5-dimethylthiazol-2-yl)-5(3-carboxymethoxyphenol)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) analysis. The highest level
Wu-Jang Huang; Meei-Fang Shue
Gas turbine exhaust heat recovery by hybrid steam\\/ternary aqueous immiscible liquid cycle
The concept of the dual pressure steam\\/pure organic hybrid immiscible liquid cycle applied to recover exhaust heat from gas turbines is extended to include organic mixtures. Thermodynamics of the resulting ternary working fluid cycle is presented. For the cycle arrangement analysed it is calculated that the ternary steam\\/nonane\\/decane cycle with the organic very nonane rich produces about 2% more work
Cfd and Analytical Analysis of Exhaust System of a Gas Turbine Used in a Ship
In this study, exhaust system of the gas turbine of a ship with CODOG (Combined Diesel Or Gas-turbine) system is analyzed both analytically and numerically. The results obtained from these two different methods are then compared. The flow and heat transfer analysis of the exhaust system is done using a full scale two-dimensional (2-D) model and in the simulation velocity vectors, pressure and temperature fields are obtained. The gas turbine exhaust system velocity is 40 m/s, especially just after the inlet. For the mathematical model, time-averaged, steady-state, mean flow equations of continuity, momentum and energy equations can be written in Cartesian tensor notation. In commercially available computational fluid dynamics (CFD) code FLUENT 6.2, the governing equations are discretized using second order upwind interpolation scheme, and the discretized equations are solved using SIMPLEC algorithm. The Standard k-? turbulence model is used for the turbulence closure. The boundary layer meshes are applied for obtaining more precise results, especially in the vicinity of walls. It is shown that the CFD calculations can be applied to such a practical problem to improve analysis performance. In conclusion, velocity vectors, temperature and pressure fields and pressure losses calculated CFD and analytical calculations are compared with numerical results.
Bayraktar, Seyfettin; Safa, Aykut; Yilmaz, Tamer
The Measurement of Fuel-Air Ratio by Analysis of the Oxidized Exhaust Gas
An investigation was made to determine a method of measuring fuel-air ratio that could be used for test purposes in flight and for checking conventional equipment in the laboratory. Two single-cylinder test engines equipped with typical commercial engine cylinders were used. The fuel-air ratio of the mixture delivered to the engines was determined by direct measurement of the quantity of air and of fuel supplied and also by analysis of the oxidized exhaust gas and of the normal exhaust gas. Five fuels were used: gasoline that complied with Army-Navy Fuel Specification, No. AN-VV-F-781 and four mixtures of this gasoline with toluene, benzene, and xylene. The method of determining the fuel-air ratio described in this report involves the measurement of the carbon-dioxide content of the oxidized exhaust gas and the use of graphs or the presented equation. This method is considered useful in aircraft, in the field, or in the laboratory for a range of fuel-air ratios from 0.047 to 0.124
Memm, J. Lawrence, Jr.
The Measurement of Fuel-Air Ratio by Analysis for the Oxidized Exhaust Gas
An investigation was made to determine a method of measuring fuel-air ratio that could be used for test purposes in flight and for checking conventional equipment in the laboratory. Two single-cylinder test engines equipped with typical commercial engine cylinders were used. The fuel-air ratio of the mixture delivered to the engines was determined by direct measurement of the quantity of air and of fuel supplied and also by analysis of the oxidized exhaust gas and of the normal exhaust gas. Five fuels were used: gasoline that complied with Army-Navy fuel Specification No. AN-VV-F-781 and four mixtures of this gasoline with toluene, benzene, and xylene. The method of determining the fuel-air ratio described in this report involves the measurement of the carbon-dioxide content of the oxidized exhaust gas and the use of graphs for the presented equation. This method is considered useful in aircraft, in the field, or in the laboratory for a range of fuel-air ratios from 0.047 to 0.124.
Gerrish, Harold C.; Meem, J. Lawrence, Jr.
Emission factor of exhaust gas constituents during the pyrolysis of zinc chloride immersed biosolid.
Pyrolysis enables ZnCl2 immersed biosolid to be reused, but some hazardous air pollutants are emitted during this process. Physical characteristics of biosolid adsorbents were investigated in this work. In addition, the constituents of pyrolytic exhaust were determined to evaluate the exhaust characteristics. Results indicated that the pyrolytic temperature was higher than 500 �C, the specific surface area was >900 m(2)/g, and the total pore volume was as much as 0.8 cm(3)/g at 600 �C. For non-ZnCl2 immersed biosolid pyrolytic exhaust, VOC emission factors increased from 0.677 to 3.170 mg-VOCs/g-biosolid with the pyrolytic temperature increase from 400 to 700 �C, and chlorinated VOCs and oxygenated VOCs were the dominant fraction of VOC groups. VOC emission factors increased about three to seven times, ranging from 1.813 to 21.448 mg/g for pyrolytic temperatures at 400-700 �C, corresponding to the mass ratio of ZnCl2 and biosolid ranging from 0.25-2.5. PMID:23471775
Chiang, Hung-Lung; Lin, Kuo-Hsiung; Chiu, Hua-Hsien
Experimental studies of the dilution of vehicle exhaust pollutants by environment-protecting pervious pavement.
This study determines whether environment-protecting pervious pavement can dilute pollutants immediately after emissions from vehicle. The turbulence-driven dry-deposition process is too slow to be considered in this aspect. The pavement used is the JW pavement (according to its inventors name), a high-load-bearing water-permeable pavement with patents in over 100 countries, which has already been used for more than 8 years in Taiwan and is well suited to replacing conventional road pavement, making the potential implementation of the study results feasible. The design of this study included two sets of experiments. Variation of the air pollutant concentrations within a fenced area over the JW pavement with one vehicle discharging emissions into was monitored and compared with results over a non-JW pavement. The ambient wind speed was low during the first experiment, and the results obtained were highly credible. It was found that the JW pavement diluted vehicle pollutant emissions near the ground surface by 40%-87% within 5 min of emission; whereas the data at 2 m height suggested that about 58%-97% of pollutants were trapped underneath the pavement 20 min after emission. Those quantitative estimations may be off by +/- 10%, if errors in emissions and measurements were considered. SO2 and CO2 underwent the most significant reduction. Very likely, pollutants were forced to move underneath due to the special design of the pavement. During the second experiment, ambient wind speeds were high and the results obtained had less credibility, but they did not disprove the pollutant dilution capacity of the JW pavement. In order to track the fate of pollutants, parts of the pavement were removed to reveal a micro version of wetland underneath, which could possibly hold the responsibility of absorbing and decomposing pollutants to forms harmless to the environment and human health. PMID:22393814
Liu, Chung-Ming; Chen, Jui-Wen; Tsai, Jen-Hui; Lin, Wei-Shian; Yen, M-T; Chen, Ting-Hao
Integrated exhaust gas analysis system for aircraft turbine engine component testing
An integrated exhaust gas analysis system was designed and installed in the hot-section facility at the Lewis Research Center. The system is designed to operate either manually or automatically and also to be operated from a remote station. The system measures oxygen, water vapor, total hydrocarbons, carbon monoxide, carbon dioxide, and oxides of nitrogen. Two microprocessors control the system and the analyzers, collect data and process them into engineering units, and present the data to the facility computers and the system operator. Within the design of this system there are innovative concepts and procedures that are of general interest and application to other gas analysis tasks.
Summers, R. L.; Anderson, R. C.
A Gas Chromatograph/Mass Spectrometer System for UltraLow-Emission Combustor Exhaust Studies
A gas chromatograph (GC)/mass spectrometer (MS) system that allows the speciation of unburnt hydrocarbons in the combustor exhaust has been developed at the NASA Lewis Research Center. Combustion gas samples are withdrawn through a water-cooled sampling probe which, when not in use, is protected from contamination by a high-pressure nitrogen purge. The sample line and its connecting lines, filters, and valves are all ultraclean and are heated to avoid condensation. The system has resolution to the parts-per-billion (ppb) level.
Brabbs, Theodore A.; Wey, Chowen Chou
Quantification of diesel exhaust gas phase organics by a thermal desorption proton transfer reaction mass spectrometer
A new approach was developed to measure the total abundance of long chain alkanes (C12 and above) in urban air using thermal desorption with a proton transfer reaction mass spectrometer (PTR-MS). These species are emitted in diesel exhaust and may be important precursors to secondary organic aerosol production in urban areas. Long chain alkanes undergo dissociative proton transfer reactions forming a series of fragment ions with formula CnH2n+1. The yield of the fragment ions is a function of drift conditions. At a drift field strength of 80 Townsends, the most abundant ion fragments from C10 to C16 n-alkanes were m/z 57, 71 and 85. The PTR-MS is insensitive to n-alkanes less than C8 but displays an increasing sensitivity for larger alkanes. Higher drift field strengths yield greater normalized sensitivity implying that the proton affinity of the long chain n-alkanes is less than H2O. Analysis of diesel fuel shows the mass spectrum was dominated by alkanes (CnH2n+1), monocyclic aromatics, and an ion group with formula CnH2n-1 (m/z 97, 111, 125, 139). The PTR-MS was deployed in Sacramento, CA during the Carbonaceous Aerosols and Radiative Effects Study field experiment in June 2010. The ratio of the m/z 97 to 85 ion intensities in ambient air matched that found in diesel fuel. Total diesel exhaust alkane concentrations calculated from the measured abundance of m/z 85 ranged from the method detection limit of ~1 ?g m-3 to 100 ?g m-3 in several air pollution episodes. The total diesel exhaust alkane concentration determined by this method was on average a factor of 10 greater than the sum of alkylbenzenes associated with spark ignition vehicle exhaust.
Erickson, M. H.; Wallace, H. W.; Jobson, B. T.
Effects of Exhaust Gas Recirculation on SI Engines at Wide Open Throttle
Exhaust gas recirculation, a charge dilution technique, has proven to be an effective method of reducing NOx emissions and fuel consumption of spark ignition engines. Wide open throttle operation also increases overall engine efficiency by reducing the pumping losses caused by throttling. In this study, the emissions and fuel economy benefits of exhaust gas recirculation (EGR) at wide open throttle conditions were quantified using a 2.4L port-injected engine. Engine performance and emissions data were recorded as the percentage of EGR in the intake charge was increased from zero to just above thirty percent (the EGR limit). This EGR percentage, in-cylinder pressure measurements, and the temperatures and pressures of the intake and exhaust were all recorded to ensure stable operating conditions. These tests were performed with a stoichiometric air-fuel ratio at a constant speed of 2000 rpm at wide open throttle. The variation of brake specific fuel consumption and emissions (in particular NOx) with increasing EGR percentages was analyzed.
Bronson, Sydney; Puzinauskas, Paulius
Experimental and three-dimensional CFD investigation in a gas turbine exhaust system
Both experimental and three-dimensional CFD investigations are carried out in a scale model of an industrial gas turbine exhaust system to better understand its complex flow field and to validate CFD prediction capabilities for improved design applications. The model consists of an annular diffuser passage with struts, followed by turning vanes and a rectangular plenum with side exhaust. Precise measurements of total/static pressure and flow velocity distributions at the model inlet, strut outlet and model outlet are made using aerodynamic probes and locally a Laser Doppler Velocimeter (LDV). Numerical analyses of the model internal flow field are performed utilizing a three-dimensional Navier-Stokes (N-S) calculation method with the industry standard {kappa}-{epsilon} turbulence model. Both the experiments and computations are carried out for three load conditions: full speed no load (FSNL), full speed mid load (FSML, 57% load), and full speed full load (FSFL). Based on the overall comparison between the measurements and CFD predictions, this study concludes that the applied N-S method is capable of predicting complicated gas turbine exhaust system flows for design applications.
Sultanian, B.K. [General Electric Co., Schenectady, NY (United States). GE Power Systems; Nagao, S.; Sakamoto, T. [Toshiba Corp., Yokohama (Japan). Heavy Apparatus Engineering Lab.
Method for simultaneously removing SO.sub.2 and NO.sub.X pollutants from exhaust of a combustion system
A method is disclosed for removing pollutants from the exhaust of combustion systems burning fuels containing substantial amounts of sulfur and nitrogen. An exemplary method of the invention involves the formation and reaction of a sorbent comprising calcium magnesium acetate (CMA). The CMA is either dry-sprayed (in the form of a fine powder) or wet-sprayed in an aqueous solution in a high temperature environment such as a combustion chamber. The latter technique is feasible since CMA is a uniquely water-soluble form of calcium and magnesium. When the dispersed particles of CMA are heated to a high temperature, fine calcium and magnesium oxide particles, which are hollow with thin and highly porous walls are formed, affording optimum external and internal accessibility for reacting with toxic gaseous emissions such as SO.sub.2. Further, the combustion of the organic acetate portion of the sorbent results in the conversion of NO.sub.x to N.sub.2.
Levendis, Yiannis A. (Boston, MA); Wise, Donald L. (Belmont, MA)
Catalysts as Sensors--A Promising Novel Approach in Automotive Exhaust Gas Aftertreatment
Sensors that detect directly and in situ the status of automotive exhaust gas catalysts by monitoring the electrical properties of the catalyst coating itself are overviewed. Examples included in this review are the in-situ determination of the electrical impedance of three-way catalysts based on ceria-zirconia solutions and of lean NOx traps of earth-alkaline based coatings, as well as approaches to determine the ammonia loading in Fe-SCR-zeolites with electrical ac measurements. Even more sophisticated approaches based on interactions with electromagnetic waves are also reviewed. For that purpose, metallic stick-like antennas are inserted into the exhaust pipe. The catalyst properties are measured in a contactless manner, directly indicating the catalyst status. The radio frequency probes gauge the oxygen loading degree of three-way catalysts, the NOx-loading of lean NOx traps, and the soot loading of Diesel particulate filters.
Moos, Ralf
Numerical Simulation of Membrane Reactor for Detritiation of Plasma Exhaust Gas
One of the design targets for the ITER Tokamak Exhaust Processing system is to suppress the loss of tritium to less than 10{sup -5} g/h into the Normal Vent Detritiation System of the Tritium Plant. The plasma exhaust gas, therefore, needs to be processed with an overall tritium removal efficiency of about 10{sup 8}. Such a high decontamination factor can be achieved by multistage processes. The third step of the three step CAPER process developed at the TLK is based on a so-called permeator catalyst (PERMCAT) reactor, a direct combination of a Pd/Ag permeation membrane and a catalyst bed. In this work, a numerical simulation of the PERMCAT reactor was performed and the result was compared with experimental data.
Munakata, K. [Kyushu University (Japan); Bornschein, B. [Forschungszentrum Karlsruhe (Germany); Corneli, D. [Forschungszentrum Karlsruhe (Germany); Glugla, M. [Forschungszentrum Karlsruhe (Germany)
Biodiesel Impacts on Compression Ignition Engine (CIE): Analysis of Air Pollution Issues Relating to Exhaust Emissions
In cities across the globe, the personal automobile is the single greatest polluter, as emissions from millions of vehicles on the road add up to a planet-wide problem. Vegetable oils have become more attractive recently because of their environmental benefits and the fact that they are made from renewable resources. With recent increases in petroleum prices and uncertainties concerning petroleum
Responses of spruce seedlings (Picea abies) to exhaust gas under laboratory conditions--I. Plant-insect interactions.
The effects of motor vehicle exhaust gas on Norway spruce seedlings (Picea abies (L.) Karst) and plant-insect interaction of spruce shoot aphid (Cinara pilicornis Hartig) was studied. The exhaust gas concentrations in the fumigation chambers were monitored and controlled by measuring the concentration of nitrogen oxides (NO(x)) with a computer aided feedback system. The concentrations of major exhaust gas components (black carbon [BC], fine particles, VOCs and carbonyl compounds) in the chamber air were also measured. Responses of Norway spruce seedlings to a 2 and 3-week exhaust gas exposure and subsequent performance of spruce shoot aphid were studied using realistic exposure regimes; 50, 100 and 200 ppb NO(x). The feedback control system based on NO(x) concentrations proved an adequate and practical means for controlling the concentration of exhaust gases and studying plant responses in controlled environment chambers. The exhaust exposure resulted in increased concentrations of proline, glutamine, threonine, aspartic acid, glycine and phenylalanine and decreased concentration of arginine, serine, alanine and glycine in young needles. No changes in soluble N concentrations were observed. The results are interpreted as a stress response rather than use of NO(x) as a nitrogen source. No changes in total phenolics and only transient changes in some individual terpene concentrations were detected. The exhaust gas exposure stressed the exposed seedlings, but had no significant effect on N metabolism or the production of defence chemicals. Aphid performance was not significantly affected. Soluble N, secondary metabolism and aphid performance were not sensitive to exhaust gas exposure during shoot elongation in Norway spruce. PMID:15093012
Viskari, E L; Surakka, J; Pasanen, P; Mirme, A; K�ssi, S; Ruuskanen, J; Holopainen, J K
High Speed H2O Concentration Measurements Using Absorption Spectroscopy to Monitor Exhaust Gas
This paper demonstrates the potential for fast absorption spectroscopy measurements in diesel-engine exhaust to track H2O concentration transients. Wavelength-agile absorption spectroscopy is an optical technique that measures broadband absorption spectra between 10kHz and 100 MHz. From these measured spectra, gas temperature and absorber concentration can be determined. The Fourier-domain mode-locking (FDML) laser is becoming recognized as one of the most robust and reliable wavelength-agile sources available. H2O concentration measurements during combustion events at crank angle resolved speeds are beneficial for a wide variety of applications, such as product improvements for industry, control and reliability checks for experimental researchers, and measures of fit for numerical simulations. The difficulties associated with measuring diesel exhaust compared to in-cylinder measurements are discussed. A full description of the experimental configuration and data processing is explained. Measurements of engine exhaust H2O transients with 10- s temporal resolution are presented for a range of engine conditions.
Kranendonk, Laura [ORNL; Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL; Partridge Jr, William P [ORNL
Variable-geometry turbocharger with asymmetric divided volute for engine exhaust gas pulse optimization
A turbine assembly for a variable-geometry turbocharger includes a turbine housing defining a divided volute having first and second scrolls, wherein the first scroll has a substantially smaller volume than the second scroll. The first scroll feeds exhaust gas to a first portion of a turbine wheel upstream of the throat of the wheel, while the second scroll feeds gas to a second portion of the wheel at least part of which is downstream of the throat. Flow from the second scroll is regulated by a sliding piston. The first scroll can be optimized for low-flow conditions such that the turbocharger can operate effectively like a small fixed-geometry turbocharger when the piston is closed. The turbine housing defines an inlet that is divided by a dividing wall into two portions respectively feeding gas to the two scrolls, a leading edge of the dividing wall being downstream of the inlet mouth.
Serres, Nicolas (Epinal, FR)
Multiple Exhaust Nozzle Effects on J-2X Gas Generator Outlet Impedance
The current test setup of the J-2X gas generator system uses a multiple nozzle configuration to exhaust hot gases to drive the propellant supply turbines. Combustion stability assessment of this gas generator design requires knowledge of the impedance effects the multiple nozzle configuration creates on the combustion chamber acoustic modes. Parallel work between NASA and Sierra Engineering is presented, showing two methods used to calculate the effective end impedance resulting from multiple nozzle configurations. The NASA method is a simple estimate of the effective impedance using the long wavelength approximation. Sierra Engineering has developed a more robust numerical integration method implemented in ROCCID to accommodate for multiple nozzles. Analysis using both methods are compared to J-2X gas generator test data collected over the past year.
Kenny, R. Jeremy; Muss, Jeffrey; Hulka, James R.; Casiano, Matthew
Alternative catalyst and exhaust gas sensor work at Argonne National Laboratory
Research programs at Argonne National Laboratory in the areas of automobile emissions monitoring and control are described. The mandate to improve automobile efficiency while reducing Pollution requires the development of new catalysts for exhaust emissions control that are capable of functioning efficiently under lean-burn engine operating conditions. It is also desirable that the use of expensive noble metal catalysts be avoided. NO{sub x} emissions will not be efficiently controlled by the current three-way, supported noble metal catalysts under lean-burn conditions. New catalysts are being sought that could effect the selective catalytic reduction (SCR) of NO{sub x} by exhaust hydrocarbons in the presence of oxygen. Molecular sieve zeolites of the ZSM-5 and ferrierite types, ion-exchanged with copper ions, are the best of the catalysts known to effect this chemistry, but the mechanism of the SCR is still not understood. In this project the authors will first undertake the investigation of the SCR of NO using model reactions to test postulated mechanistic pathways. Initial experiments have been devised to investigate the possible participation of metal alkyl complexes, metal oxime complexes, N-alkyl-N-nitroso-alkylaminato-metal complexes, and metal nitrile complexes in the zeolites. ANL will also develop microsensors, based on surface acoustic wave (SAW) chemical sensing techniques, and a micro mass-spectrometer (MS) for tailpipe or engine-out emission monitoring. The sensor configurations and sensing techniques of the proposed SAW and micro-MS are described.
Iton, L.E.; Maroni, V.A.; Dieckman, S.L.; Sheen, S.H.; Raptis, A.C.
Exhaust-gas imaging via planar laser- induced fluorescence of sulfur dioxide
The potential use of planar laser-induced fluorescence (PLIF) of sulfur dioxide (SO2) for visualization of exhaust-gas distributions is outlined and demonstrated. Strong absorption features in the UV spectral range allow excitation of SO2 with the fourth harmonic of a Nd:YAG laser at 266 nm. Fluorescence emissions are mostly red-shifted and can be easily detected in single-shot imaging arrangements with a good signal-to-noise ratio. This study uses a premixed methane/air flame that is doped with SO2 to demonstrate the technique. The signal strength has a pronounced temperature dependence for excitation at 266 nm.
Sick, V.
The Air Pollution Technology Branch's (APPCD, NRMRL)flue gas cleaning program supports New Source Performance Standards regulations development and has fostered the development of technologies that today are considered industry standards. These include both dry and wet flue gas d...
Direct and Indirect Applications of Dielectric Barrier Discharge Plasma to Catalytic Reduction of Nitrogen Oxides from Exhaust Gas
Dielectric barrier discharge (DBD) plasma was utilized to oxidize NO contained in the exhaust gas to NO2, ultimately improve the selective catalytic reduction of nitrogen oxides (NOx). In the one case, DBD was created directly in the exhaust gas (direct application), and in the an other case, ozone produced by DBD was injected into the exhaust gas (indirect application). A comparative study between such direct and indirect applications of DBD plasma was made in terms of the NOx removal efficiency and the energy consumption. The NO2 content in the exhaust gas was changed by the voltage applied to the DBD device (for direct application) or by the amount of ozone added to the exhaust gas (for indirect application). In both cases, NO was easily oxidized to NO2, and the change in NO2 content largely affected the NOx removal performance of the catalytic reactor placed downstream, where both NO and NO2 were reduced to N2 in the presence of ammonia as the reducing agent. The experiments were primarily concerned with the effect of reaction temperature on the catalytic NOx reduction at various NO2 contents. The direct and indirect applications of DBD were found to remarkably improve the catalytic NOx reduction, especially at low temperatures.
Young, Sun Mok
Use of exhaust gas recirculation as a control approach for thermoacoustic instabilities
Investigation into exhaust gas recirculation (EGR) as a method for reducing costs of postcombustion carbon capture in gas turbine systems reveals that EGR offers potential applications as a control strategy for thermoacoustic instabilities. Introduction of EGR allows semi-independent variation of the operating parameter of flame temperature and characteristic flame length scales, known to play a primary role in the phase of the thermoacoustic coupling mechanism. Measurements were made showing the ability of EGR to reduce the amplitude of thermoacoustic oscillations over a range of operating conditions in a laboratory scale, swirled dump combustor, without affecting the flame temperature. Theoretical analysis was also performed to investigate the limitations on the ability of this approach to influence dynamics.
Ranalli, J.; Ferguson, D.
Exhaust-gas measurements from NASAs HYMETS arc jet.
Arc-jet wind tunnels produce conditions simulating high-altitude hypersonic flight such as occurs upon entry of space craft into planetary atmospheres. They have traditionally been used to study flight in Earth's atmosphere, which consists mostly of nitrogen and oxygen. NASA is presently using arc jets to study entry into Mars' atmosphere, which consists of carbon dioxide and nitrogen. In both cases, a wide variety of chemical reactions take place among the gas constituents and with test articles placed in the flow. In support of those studies, we made measurements using a residual gas analyzer (RGA) that sampled the exhaust stream of a NASA arc jet. The experiments were conducted at the HYMETS arc jet (Hypersonic Materials Environmental Test System) located at the NASA Langley Research Center, Hampton, VA. This report describes our RGA measurements, which are intended to be used for model validation in combination with similar measurements on other systems.
Miller, Paul Albert
Integrated capture of fossil fuel gas pollutants including CO.sub.2 with energy recovery
A method of reducing pollutants exhausted into the atmosphere from the combustion of fossil fuels. The disclosed process removes nitrogen from air for combustion, separates the solid combustion products from the gases and vapors and can capture the entire vapor/gas stream for sequestration leaving near-zero emissions. The invention produces up to three captured material streams. The first stream is contaminant-laden water containing SO.sub.x, residual NO.sub.x particulates and particulate-bound Hg and other trace contaminants. The second stream can be a low-volume flue gas stream containing N.sub.2 and O.sub.2 if CO2 purification is needed. The final product stream is a mixture comprising predominantly CO.sub.2 with smaller amounts of H.sub.2O, Ar, N.sub.2, O.sub.2, SO.sub.X, NO.sub.X, Hg, and other trace gases.
Ochs, Thomas L. (Albany, OR); Summers, Cathy A. (Albany, OR); Gerdemann, Steve (Albany, OR); Oryshchyn, Danylo B. (Philomath, OR); Turner, Paul (Independence, OR); Patrick, Brian R. (Chicago, IL)
Exhaust-gas recirculation for retrofit NOx control on natural gas engines. Topical report, January-April 1988
Data on exhaust-gas recirculation obtained from Tenneco Gas Transportation Company were reviewed and analyzed, and a basic EGR system design and cost estimate were developed. EGR can provide practical NOx reductions of up to 50% in 2-cycle natural gas engines. The amount of NO reduction achievable is dependent on the initial baseline NOx emissions of the engine. On the basis of NOx reduction per unit of costs, EGR was found to be more cost effective than selective catalytic reduction. EGR is considered to provide a practical retrofit NOx control method in applications where the level of NOx control achievable with EGR meet regulatory requirements. One specific application is emissions offset to enable installation of additional engine horsepower. Also, EGR could become the primary NOx control method for any regulation in which costs are a major consideration.
Urban, C.M.
Air pollution from aircraft. [jet exhaust - aircraft fuels/combustion efficiency
A model which predicts nitric oxide and carbon monoxide emissions from a swirl can modular combustor is discussed. A detailed analysis of the turbulent fuel-air mixing process in the swirl can module wake region is reviewed. Hot wire anemometry was employed, and gas sampling analysis of fuel combustion emissions were performed.
Heywood, J. B.; Chigier, N. A.
Infiltration of Engine Exhaust Into Natural Gas-Fired Compressor Stations
Nitrogen oxides concentrations were measured inside buildings at two natural gas fired compressor engine stations. Average concentrations as high as 1.12?mg\\/m NO2 11.4?mg\\/m NO were found in the main engine buildings. Data on indoor concentration, engine emissions, ventilation and infiltration were evaluated with a pollutant mass balance model. The modeling results show that up to 4% of the total engine
The report gives results of an engineering study and design of methods for scrubbing the exhaust of static-tested solid rockets. Pollutants of major concern were hydrogen chloride and hydrogen fluoride gases. The best process for removing these gases was found to be a gas-atomize...
Exposure to hazardous volatile pollutants back diffusing from automobile exhaust systems.
As back diffusion gases from automobiles are significant sources of in-vehicular pollution, we investigated eight automobiles, five for back diffusion (driving) measurements and three for reference conditions (non-driving). To characterize the back diffusion emission conditions, seven volatile organic compounds (VOC) and four carbonyl compounds (CCs) were measured along with dilution-to-threshold (D/T) ratio. The data obtained from back diffusion measurements were examined after having been divided into three subcategories: (i) driving and non-driving, (ii) with and without automobile upgrading (sealing the inner line), and (iii) differences in CO emission levels. Among the VOCs, the concentrations of toluene (T) was found to be the highest (range: 13.6-155 ppb), while benzene (0.19-1.47 ppb) was hardly distinguishable from its ambient levels. Other VOCs (xylene, trimethylbenzene, and styrene) were generally below <1 ppb. Unlike VOCs, the concentrations (ppb) of CCs were seen at fairly enhanced levels: 30.1-95 (formaldehyde), 34.6-87.2 (acetaldehyde), 4.56-34.7 (propionaldehyde), and 3.45-68.8 (butyraldehyde). The results of our study suggest that the back diffusion phenomenon, if occurring, can deteriorate in-vehicle air, especially with the most imminent health hazards from a compound such as formaldehyde in view of its exceedance pattern over common guidelines. PMID:23072984
Rahman, Md Mahmudur; Kim, Ki-Hyun
Simultaneous removal of NO(x) and SO2 in exhausted gas through landfill leachate.
Simultaneous removal of NO(x) and SO2 from exhausted gas were investigated by studying co-culture of sulfate reducing bacteria and anaerobic denitrifying bacteria, separated from landfill leachate. When H2S, generated by sulfate reducing bacteria was chosen as the sole electron donor for anaerobic denitrifying bacteria, the co-culture system demonstrated a faster NO removal rate, higher stability and better permanence. When the feed gas flow rates of N2 and SO2 were maintained constant at 0.1 m3/h and 16 ml/min respectively, the maximum NO-removal rate could be achieved at over 92% with NO feed gas kept between 2-6 ml/min, while the SO2 removal rate was always above 95%. Long-term continuous removal of NO exhibited an evident periodicity of five days, however, the fluctuation range of NO-removal was decreasing. Moreover, the decrease of the gas flow rate and the increase in NO inlet concentration could contribute to a higher NO- removal rate. PMID:21250607
Han, Yaqiong; Zhang, Weijiang
SIGIS HR: a system for measurement of aircraft exhaust gas under normal operating conditions of an airport
To gather information about the impact on the environment caused by airport operations, knowledge about the amount of gases such as CO or NOX emitted by aircraft engines on the ground is important. In order to avoid influences on airport operations an analysis system for this application has to enable measurements on the hot jet engine exhaust gas from a distance. The infrared radiation emitted by the hot gas can be analysed by Fourier-transform infrared spectroscopy to determine the composition of the gas. To fulfil this task, a new version of the scanning infrared gas imaging system (SIGIS HR), using relatively high spectral resolution (0.2 cm-1), has been developed. The period of time for measurements on the engine exhaust gas of an aircraft on the ground is short during normal airport operations. Hence the remote sensing system has to be aligned to the exhaust gas plume quickly. For this reason the system is equipped with a scanning mirror actuated by stepper motors in order to allow fast changes of the line of sight. An infrared camera combined with a DSP-system enables automatic alignment of the system to the hot exhaust gas and tracking of a moving engine via online analysis of the infrared image. Additionally fast scans with low spectral resolution of the area around the engine-outlet can be performed. On the basis of the low resolution data the optimal direction for the exhaust gas measurement can be found using several automatic evaluation- and positioning-algorithms. After the SIGIS HR-system has been positioned correctly it is operated in high- resolution-mode in order to quantify the target compounds.
Rusch, Peter; Harig, Roland; Matz, Gerhard; Sch�fer, Klaus; Jahn, Carsten; Utzig, Selina
Dynamic instabilities in spark-ignited combustion engines with high exhaust gas recirculation
We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global probability distribution that describes the pre-spark state of in-cylinder fuel mixing. The proposed model does a good job of simulating combustion instabilities observed in both lean-fueling engine experiments and in experiments where nitrogen dilution is used to simulate some of the combustion inhibition of EGR. When used to simulate high internal EGR operation, the model exhibits a range of global bifurcations and chaos that appear to be very robust. We use the model to show that it should be possible to reduce high EGR combustion instabilities by switching from internal to external EGR.
Daw, C. Stuart; Finney, Charles E. A.
Platform for a Hydrocarbon Exhaust Gas Sensor Utilizing a Pumping Cell and a Conductometric Sensor
Very often, high-temperature operated gas sensors are cross-sensitive to oxygen and/or they cannot be operated in oxygen-deficient (rich) atmospheres. For instance, some metal oxides like Ga2O3 or doped SrTiO3 are excellent materials for conductometric hydrocarbon detection in the rough atmosphere of automotive exhausts, but have to be operated preferably at a constant oxygen concentration. We propose a modular sensor platform that combines a conductometric two-sensor-setup with an electrochemical pumping cell made of YSZ to establish a constant oxygen concentration in the ambient of the conductometric sensor film. In this paper, the platform is introduced, the two-sensor-setup is integrated into this new design, and sensing performance is characterized. Such a platform can be used for other sensor principles as well.
Biskupski, Diana; Geupel, Andrea; Wiesner, Kerstin; Fleischer, Maximilian; Moos, Ralf
Measurement of exhaust gas recirculation rate by laser-induced fluorescence in engine
The objective of this study is to measure by planar laser-induced fluorescence the exhaust gas recirculation (EGR) rate in the combustion chamber of an optical engine to quantify the stratification phenomena used in the new combustion strategy. From the results obtained in a high pressure-high temperature (HP-HT) facility, the tracer chosen for this aim is 3-pentanone. This paper presents a quantitative measurement of the EGR rate in the engine and a post-processing model with a correction and calibration procedure by considering the influence of temperature and pressure on the absorption cross-section and the 3-pentanone fluorescence quantum yield from the results established in the HP-HT facility. The stratification phenomena are quantified by using 3-pentanone fluorescence for two different configurations of EGR introduction in the engine. The local fluorescence measurements in the HP-HT facility are also compared with planar fluorescence measurements in the optical engine.
Morin, C.; Modica, V.; Guibert, P.
Impact of exhaust gas recirculation (EGR) on the oxidative reactivity of diesel engine soot
This paper expands the consideration of the factors affecting the nanostructure and oxidative reactivity of diesel soot to include the impact of exhaust gas recirculation (EGR). Past work showed that soot derived from oxygenated fuels such as biodiesel carries some surface oxygen functionality and thereby possesses higher reactivity than soot from conventional diesel fuel. In this work, results show that EGR exerts a strong influence on the physical properties of the soot which leads to enhanced oxidation rate. HRTEM images showed a dramatic difference between the burning modes of the soot generated under 0 and 20% EGR. The soot produced under 0% EGR strictly followed an external burning mode with no evidence of internal burning. In contrast, soot generated under 20% EGR exhibited dual burning modes: slow external burning and rapid internal burning. The results demonstrate clearly that highly reactive soot can be achieved by manipulating the physical properties of the soot via EGR. (author)
Al-Qurashi, Khalid; Boehman, Andre L. [The EMS Energy Institute, The Pennsylvania State University, 405 Academic Activities Bldg., University Park, PA 16802 (United States)
Effect of operating conditions on the exhaust emissions from a gas turbine combustor
Exhaust concentrations of total unburned hydrocarbons, carbon monoxide, and nitric oxide were measured from a single J-57 combustor liner installed in a 30 diameter test section. Tests were conducted over a range of inlet total pressures from 1 to 20 atmospheres, inlet total temperatures from 310 to 590 K, reference velocities from 8 to m/sec, and fuel-air ratios from 0.004 to 0.015. Most of the data were obtained using ASTM A-1 fuel; however, a limited number of tests was performed with natural gas fuel. Combustion efficiency and emission levels are correlated with operating conditions. Sampling error at operating conditions for which combustion efficiency was below about 90 percent resulted in abnormally low readings for hydrocarbon emissions.
Briehl, D.; Papathakos, L.; Strancar, R. J.
The impact of using biodiesel\\/marine gas oil blends on exhaust emissions from a stationary diesel engine
The purpose of this work was to investigate the impact of marine gas oil (MGO)\\/biodiesel blends on the exhaust emissions and fuel consumption in a single cylinder, stationary, diesel engine. Three different origins of biodiesel were used as the blending feedstock with the reference MGO, at proportions of 5 and 10% by volume. Methyl esters were examined according to the
G. Karavalakis; E. Tzirakis; L. Mattheou; S. Stournas; F. Zannikos; D. Karonis
Calculations of economy of 18-cylinder radial aircraft engine with exhaust-gas turbine geared to the crankshaft
Calculations based on dynamometer test-stand data obtained on an 18-cylinder radial engine were made to determine the improvement in fuel consumption that can be obtained at various altitudes by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine-shaft work.
Hannum, Richard W; Zimmerman, Richard H
Tracer gas studies were conducted around four model houses in a wind tunnel, and around one house in the field, to quantify re-entrainment and dispersion of exhaust gases released from residential indoor radon reduction systems. Re-entrainment tests in the field suggest that acti...
Tritium Recovery at Fusion Facility 6.Development of Exhaust Gas and Effluent Liquid Treatment System for LHD
In order to realize deuterium plasma control experiments using the Large Helical Device(LHD), NIFS is planning to install a tritium recovery system for use on exhaust gas and effluent liquid. Besides applying the conventional and proved recovery system, NIFS has made development plans for implementation of a compact and less waste generating recovery system by applying the latest technologies such as tritiated water vapor removal with a membrane type dehumidifier and tritium gas extraction with a proton conducting cell.
Asakura, Yamato
Pollutant swapping: greenhouse gas emissions from wetland systems constructed to mitigate agricultural pollution
Diffuse (non-point) water pollution from agricultural land continues to challenge water quality management, requiring the adoption of new land management practices. The use of constructed agricultural wetlands is one such practice, designed to trap multiple pollutants mobilised by rainfall prior to them reaching receiving water. Through capturing and storing pollutants in bottom sediments, it could be hypothesised that the abundance of nutrients stored in the anoxic conditions commonly found in these zones may lead to pollutant swapping. Under these circumstances, trapped material may undergo biogeochemical cycling to change chemical or physical form and thereby become more problematic or mobile within the environment. Thus, constructed agricultural wetlands designed to mitigate against one form of pollution may in fact offset the created benefits by 'swapping' this pollution into other forms and pathways, such as through release to the atmosphere. Pollutant swapping to the atmosphere has been noted in analogous wetland systems designed to treat municipal and industrial wastewaters, with significant fluxes of CO2, CH4 and N2O being recorded in some cases. However the small size, low level of engineering and variable nutrient/sediment inputs which are features of constructed agricultural wetlands, means that this knowledge is not directly transferable. Therefore, more information is required when assessing whether a wetland's potential to act as hotspot for pollution swapping outweighs its potential to act as a mitigation tool for surface water pollution. Here we present results from an on-going monitoring study at a trial agricultural wetland located in small a mixed-use catchment in Cumbria, UK. Estimates were made of CH4, CO2 and N2O flux from the wetland surface using adapted floating static chambers, which were then directly compared with fluxes from an undisturbed riparian zone. Results indicate that while greenhouse gas flux from the wetland may be significant, the impacts of this may be greatly diminished when considering wetland size in relation to catchment area. As such, this increased understanding will be valuable when considering the implications of rural land use management for water quality improvement. This knowledge could also be applied to further enhancing our knowledge of gas regional/global gas emissions from freshwater systems, which at the moment are poorly constrained.
Freer, Adam; Quinton, John; Surridge, Ben; McNamara, Niall
Use of tracer gas technique for industrial exhaust hood efficiency evaluation--where to sample?
A tracer gas technique using sulfur hexafluoride (SF6) was developed for the evaluation of industrial exhaust hood efficiency. In addition to other parameters, accuracy of this method depends on proper location of the sampling probe. The sampling probe should be located in the duct at a minimum distance from the investigated hood where the SF6 is dispersed uniformly across the duct cross section. To determine the minimum sampling distance, the SF6 dispersion in the duct in fully developed turbulent flow was studied at four duct configurations frequently found in industry: straight duct, straight duct-side branch, straight duct-one elbow, and straight duct-two elbows combinations. Based on the established SF6 dispersion factor, the minimum sampling distances were determined as follows: for straight duct, at least 50 duct diameters; for straight duct-side branch combination, at least 25 duct diameters; for straight duct-one elbow combination, 7 duct diameters; and for straight duct-two elbow combination, 4 duct diameters. Sampling at (or beyond) these distances minimizes the error caused by the non-homogeneous dispersion of SF6 in the duct and contributes to the accuracy of the tracer gas technique. PMID:3717012
Hampl, V; Niemel�, R; Shulman, S; Bartley, D L
We propose a cycle-resolved dynamic model for combustion instabilities in spark-ignition engines operating with high levels of exhaust gas recirculation (EGR). High EGR is important for increasing fuel efficiency and implementing advanced low-emission combustion modes such as homogenous charge compression ignition (HCCI). We account for the complex combustion response to cycle-to-cycle feedback by utilizing a global probability distribution that describes the pre-spark state of in-cylinder fuel mixing. The proposed model does a good job of simulating combustion instabilities observed in both lean-fueling engine experiments and in experiments where nitrogen dilution is used to simulate some of the combustion inhibition of EGR. When used to simulate high internal EGR operation, the model exhibits a range of global bifurcations and chaos that appear to be very robust. We use the model to show that it should be possible to reduce high EGR combustion instabilities by switching from internal to external EGR. We also explain why it might be helpful to deliberately stratify the fuel in the pre-spark gas mixture. It might be possible to extend the simple approach used in this model to other chemical reaction systems with spatial inhomogeneity.
Daw, C Stuart [ORNL; FINNEY, Charles E A [ORNL
Lightweight Exhaust Manifold and Exhaust Pipe Ducting for Internal Combustion Engines
An improved exhaust system for an internal combustion gasoline-and/or diesel-fueled engine includes an engine exhaust manifold which has been fabricated from carbon- carbon composite materials in operative association with an exhaust pipe ducting which has been fabricated from carbon-carbon composite materials. When compared to conventional steel. cast iron. or ceramic-lined iron paris. the use of carbon-carbon composite exhaust-gas manifolds and exhaust pipe ducting reduces the overall weight of the engine. which allows for improved acceleration and fuel efficiency: permits operation at higher temperatures without a loss of strength: reduces the "through-the wall" heat loss, which increases engine cycle and turbocharger efficiency and ensures faster "light-off" of catalytic converters: and, with an optional thermal reactor, reduces emission of major pollutants, i.e. hydrocarbons and carbon monoxide.
Northam, G. Burton (Inventor); Ransone, Philip O. (Inventor); Rivers, H. Kevin (Inventor)
Tank exhaust comparison with 40 CFR 61.93, Subpart H, and other referenced guidelines for Tank Farms National Emission Standards for Hazardous Air Pollutant (NESHAP) designated stacks
The US Environmental Protection Agency (EPA) promulgated National Emission Standards other than Radon from US Department of Energy (DOE) Facilities (40 CFR 61, Subpart H) on December 15, 1989. The regulations specify procedures, equipment, and test methods that.are to be used to measure radionuclide emissions from exhaust stacks that are designated as National Emission Standards for Hazardous Air Pollutant (NESHAP) stacks. Designated NESHAP stacks are those that have the potential to cause any member of the public to receive an effective dose equivalent (EDE) greater than or equal to 0.1 mrem/year, assuming all emission controls were removed. Tank Farms currently has 33 exhaust stacks, 15 of which are designated NESHAP stacks. This document assesses the compliance status of the monitoring and sampling systems for the designated NESHAP stacks.
Bachand, D.D.; Crummel, G.M.
Engineering a new reliable alpha-containing filtered exhaust gas system
From twelfth AEC air cleaning conference; Oak Ridge, Tennessee. USA (28 ; Aug 1972). in proceedings of the twelfth AEC air cleaning conference. A reliable ; exhaust system was designed to ventilate gloved enclosures in an existing ; building which was modified to provide for the safe handling of kilogram ; quantities of alpha-emitting materials. The new exhaust system was
A. B. Fuller; M. W. First
A diagnosing system is described for an exhaust gas recirculation system, comprising: means for detecting the position of the EGR valve and for producing a position signal dependent on the position of the EGR valve; and trouble detector means responsive to the valve operating signal and to the position signal for producing a trouble signal as an alarm signal when the detecting means produces a position signal of an actual closed state of the EGR value and the control means produces a valve operating signal representing an open state of the EGR valve. The detecting means is a photoelectric transducer, the photoelectric transducer comprises a photodiode and a phototransistor, and the transducer includes a shaft connected to a valve body of the EGR valve. The shaft is movable by movement of the valve body into a path between the photodiode and phototransistor, and the transducer includes a U-shaped holder having the photodiode and phototransistor facing each other on arms of the holder.
Ichikawa, K.
Effect of exhaust gas recirculation on diesel knock intensity and its mechanism
This paper presents an experimental study of the effect of exhaust gas recirculation (EGR) on diesel knock intensity, which is defined and discussed. In a previous paper, it was reported that particulate emission can be decreased by applying EGR under certain operating conditions; and the possible mechanism of the effect of EGR was presented. In the present study, the effect of EGR on diesel knock is examined under a variety of operating conditions. Diesel knock intensity is decreased considerably by EGR under the same operating conditions as when the particulate emission is decreased. A quantitative relationship between the diesel knock intensity and the maximum rate of cylinder pressure rise is obtained. The effect of EGR on diesel knock intensity is determined by both the chemical reaction rate of the initial premixed combustion (spontaneous ignition) and the fuel mass fraction prepared and burned in this stage. This is verified by measuring the ignition lag and classifying it into chemical and physical lags by a statistical technique.
Shiga, S.; Ehara, H.; Karasawa, T.; Kurabayashi, T.
Effect of operating and sampling conditions on the exhaust gas composition of small-scale power generators.
Small stationary diesel engines, like in generator sets, have limited emission control measures and are therefore responsible for 44% of the particulate matter (PM) emissions in the United States. The diesel exhaust composition depends on operating conditions of the combustion engine. Furthermore, the measurements are influenced by the used sampling method. This study examines the effect of engine loading and exhaust gas dilution on the composition of small-scale power generators. These generators are used in different operating conditions than road-transport vehicles, resulting in different emission characteristics. Experimental data were obtained for gaseous volatile organic compounds (VOC) and PM mass concentration, elemental composition and nitrate content. The exhaust composition depends on load condition because of its effect on fuel consumption, engine wear and combustion temperature. Higher load conditions result in lower PM concentration and sharper edged particles with larger aerodynamic diameters. A positive correlation with load condition was found for K, Ca, Sr, Mn, Cu, Zn and Pb adsorbed on PM, elements that originate from lubricating oil or engine corrosion. The nitrate concentration decreases at higher load conditions, due to enhanced nitrate dissociation to gaseous NO at higher engine temperatures. Dilution on the other hand decreases PM and nitrate concentration and increases gaseous VOC and adsorbed metal content. In conclusion, these data show that operating and sampling conditions have a major effect on the exhaust gas composition of small-scale diesel generators. Therefore, care must be taken when designing new experiments or comparing literature results. PMID:22442670
Smits, Marianne; Vanpachtenbeke, Floris; Horemans, Benjamin; De Wael, Karolien; Hauchecorne, Birger; Van Langenhove, Herman; Demeestere, Kristof; Lenaerts, Silvia
Instruments for testing air-pollution gas analyzers
Increasing environmental pollution stimulates the application of gas analyzers for testing the content of various admixtures in air. These instruments serve to test many types of substances, including toxic and corrosive ones over a wide range of their contents in air (5-6 orders). The requirements for testing small and very small contents (0.1-10-6%) has led to the utilization of highly
V. A. Gushchin; D. K. Kollerov
Controlling automotive exhaust emissions: successes and underlying science
Photochemical reactions of vehicle exhaust pollutants were responsible for photochemical smog in many cities during the 1960s and 1970s. Engine improvements helped, but additional measures were needed to achieve legislated emissions levels. First oxidation catalysts lowered hydrocarbon and carbon monoxide, and later nitrogen oxides were reduced to nitrogen in a two-stage process. By the 1980s, exhaust gas could be kept
Martyn V. Twigg
Practical Possibilities of High-Altitude Flight with Exhaust-Gas Turbines in Connection with Spark Ignition Engines Comparative Thermodynamic and Flight Mechanical Investigations
As a means of preparing for high-altitude flight with spark-ignition engines in conjunction with exhaust-gas turbosuperchargers, various methods of modifying the exhaust-gas temperatures, which are initially higher than a turbine can withstand are mathematically compared. The thermodynamic results first obtained are then examined with respect to the effect on flight speed, climbing speed, ceiling, economy, and cruising range. The results are so presented in a generalized form that they may be applied to every appropriate type of aircraft design and a comparison with the supercharged engine without exhaust-gas turbine can be made.
Weise, A.
Apparatus and methods of reheating gas turbine cooling steam and high pressure steam turbine exhaust in a combined cycle power generating system
In a combined cycle system having a multi-pressure heat recovery steam generator, a gas turbine and steam turbine, steam for cooling gas turbine components is supplied from the intermediate pressure section of the heat recovery steam generator supplemented by a portion of the steam exhausting from the HP section of the steam turbine, steam from the gas turbine cooling cycle and the exhaust from the HP section of the steam turbine are combined for flow through a reheat section of the HRSG. The reheated steam is supplied to the IP section inlet of the steam turbine. Thus, where gas turbine cooling steam temperature is lower than optimum, a net improvement in performance is achieved by flowing the cooling steam exhausting from the gas turbine and the exhaust steam from the high pressure section of the steam turbine in series through the reheater of the HRSG for applying steam at optimum temperature to the IP section of the steam turbine.
Tomlinson, Leroy Omar (Niskayuna, NY); Smith, Raub Warfield (Ballston Lake, NY)
NO x sorption�desorption study: application to diesel and lean-burn exhaust gas (selective NO x recirculation technique)
NOx adsorption\\/desorption capacities of barium aluminates and BaSnO3 were measured under representative exhaust gas mixture at temperatures below 550�C and compared to those of bulk BaO. The capacities are high and the test of sorption�desorption is reproducible on barium aluminate and BaSnO3, while this is not the case on BaO. The difference is due to the electronic environment of barium
S Hodjati; K Vaezzadeh; C Petit; V Pitchon; A Kiennemann
Absorption\\/desorption of NO x process on perovskites: performances to remove NO x from a lean exhaust gas
NOx adsorption\\/desorption capacities of perovskites (ABO3) were measured under representative exhaust gas mixture conditions at temperatures below 550�C, with A=Ca, Sr, Ba and B=Sn, Zr, Ti. The solids exhibited good NO2 sorption capacities with a reversible adsorption to desorption process according to the sequence Ba>Sr>Ca for A, while for element B the sequence Sn>Zr>Ti is observed. In the case of
Influence of an Optimized Thermoelectric Generator on the Back Pressure of the Subsequent Exhaust Gas System of a Vehicle
Numerous research projects in automotive engineering focus on the industrialization of the thermoelectric generator (TEG). The development and the implementation of thermoelectric systems into the vehicle environment are commonly supported by virtual design activities. In this paper a customized simulation architecture is presented that includes almost all vehicle parts which are influenced by the TEG (overall system simulation) but is nevertheless capable of real-time use. Moreover, an optimized planar TEG with minimum nominal power output of about 580 W and pressure loss at nominal conditions of 10 mbar, synthesized using the overall system simulation, and the overall system simulation itself are used to answer a generally neglected question: What influence does the position of a TEG have on the back pressure of the subsequent exhaust gas system of the vehicle? It is found that the influence of the TEG on the muffler is low, but the catalytic converter is strongly influenced. It is shown that the TEG can reduce the back pressure of an exhaust gas system so much that its overall back pressure is less than the back pressure of a standard exhaust gas system.
K�hn, Roland; Koeppen, Olaf; Kitte, Jens
Role of average speed in N?O exhaust emissions as greenhouse gas in a huge urban zone (MVMZ): would we need a cold sun?
Nowadays, the drastic pollution problems, some of them related with greenhouse gas emissions, have promoted important attempts to face and diminish the global warming effects on the Mexico Valley Metropolitan Zone (MVMZ) as well as on the huge urban zones around the world. To reduce the exhaust gas emissions, many efforts have been carried out to reformulate fuels and design new catalytic converters; however, it is well known that other variables such as socio-economic and transport structure factors also play an important role around this problem. The present study analyzes the roles played by several commonly-used three-way catalytic converters (TWC) and the average traffic speed in the emission of N(2)O as greenhouse gas. According to this study, by increasing the average traffic flow and avoiding constant decelerations (frequent stops) during common trips, remarkable environmental and economic benefits could be obtained due to the diminution of N(2)O and other contaminant emissions such as ammonia (NH(3)) and even CO(2) with the concomitant reduced fossil fuel consumption. The actions mentioned above could be highly viable to diminish, in general, the global warming effects and contamination problems. PMID:22245865
Castillo, S; Mac-Beath, I; Mejia, I; Camposeco, R; Bazan, G; Mor�n-Pineda, M; Carrera, R; G�mez, R
A temperature correlation for the radiation resistance of a thick-walled circular duct exhausting a hot gas
It is often useful to know the radiation impedance of an unflanged but thick-walled circular duct exhausting a hot gas into relatively cold surroundings. The reactive component is shown to be insensitive to temperature, but the resistive component is shown to be temperature dependent. A temperature correlation is developed permitting prediction of the radiation resistance from a knowledge of the temperature difference between the ambient air and the gas flowing from the duct, and a physical basis for this correlation is presented.
Mahan, J. R.; Cline, J. G.; Jones, J. D.
Implementation of an experimental pilot reproducing the fouling of the exhaust gas recirculation system in diesel engines
The European emission standards EURO 5 and EURO 6 define more stringent acceptable limits for exhaust emissions of new vehicles. The Exhaust Gas Recirculation (EGR) system is a partial but essential solution for lowering the emission of nitrogen oxides and soot particulates. Yet, due to a more intensive use than in the past, the fouling of the EGR system is increased. Ensuring the reliability of the EGR system becomes a main challenge. In partnership with PSA Peugeot Citro�n, we designed an experimental setup that mimics an operating EGR system. Its distinctive features are (1) its ability to reproduce precisely the operating conditions and (2) its ability to measure the temperature field on the heat exchanger surface with an Infra Red camera for detecting in real time the evolution of the fooling deposit based on its thermal resistance. Numerical codes are used in conjunction with this experimental setup to determine the evolution of the fouling thickness from its thermal resistance.
Gaborieau, C�cile; Sommier, Alain; Toutain, Jean; Anguy, Yannick; Crepeau, G�rald; Gobin, Beno�t
Non-Thermal Removal of Gaseous Pollutants
The removal of fluorine based exhaust gases such as CFC's, PFC's, NF3, and SF6 used for plasma etching of and deposition on semi-conductors is a subject of increasing interest because of safety, air pollution, and global warming issues. Conventional treatment methods for removing exhaust gas pollutants are wet scrubbing, carbon and resin adsorption, catalytic oxidation, and thermal incineration. However, there are drawbacks associated with each of these methods which include difficulties in implementation, problems with the disposal of solid and liquid pollutant waste, large water and fuel consumption, and additional pollutants such as NOx emissions which are generated in thermal incineration processes.
Srivastava, S.; McGowan, J. William; Chiu, K. C. Ray
Evaluation of Energy Saving Characteristics of a High-Efficient Cogeneration System Utilizing Gas Engine Exhaust Heat
A high efficiency cogeneration system (CGS) utilizing high temperature exhaust gas from a gas engine is proposed. In the proposed CGS, saturated steam produced in the gas engine is superheated with a super heater utilizing regenerative burner and used to drive a steam turbine generator. The heat energy is supplied by extracting steam from the steam turbine and turbine outlet low-temperature steam. Both of the energy saving characteristics of the proposed CGS and a CGS constructed by using the original gas engine (GE-CGS) were investigated and compared, by taking a case where energy for office buildings was supplied by the conventional energy systems. It was shown that the proposed CGS has energy saving rate of 24.5%, higher than 1.83 times, compared with that of the original GE-CGS.
Pak, Pyong Sik
Pollutant emissions from and within a model gas turbine combustor at elevated pressures and temperatures
Conventional and advanced gas turbine engines are coming under increased scrutiny regarding pollutant emissions. This, in turn, has created a need to obtain in-situ experimental data at practical conditions, as well as exhaust data, and to obtain the data in combustors that reflect modern designs. The in-situ data are needed to (1) assess the effects of design modifications on pollutant formation, and (2) develop a detailed data base on combustor performance for the development and verification of computer modeling. This paper reports on a novel high pressure, high temperature facility designed to acquire such data under controlled conditions and with access (optical and extractive) for in-situ measurements. To evaluate the utility of the facility, a model gas turbine combustor was selected which features practical hardware design, two rows of jets (primary and dilution) with four jets in each row, and advanced wall cooling techniques with laser drilled effusive holes. The dome is equipped with a flat-vaned swirler with vane angles of 60 degrees. Data are obtained at combustor pressures ranging from 2 to 10 atmospheres of pressure, levels of air preheat to 427 C, combustor reference velocities from 10.0 to 20.0 m/s, and an overall equivalence ratio of 0.3. Exit plane and in-situ measurements are presented for HC, O2, CO2, CO, and NO(x). The exit plane emissions of NO(x) correspond to levels reported from practical combustors and the in-situ data demonstrate the utility and potential for detailed flow field measurements.
Drennan, S. A.; Peterson, C. O.; Khatib, F. M.; Sowa, W. A.; Samuelsen, G. S.
Manganese accumulation in soil and plants along Utah roadways: A possible indication of motor vehicle exhaust pollution
An organic manganese compound is currently added to gasoline to replace tetraethyl lead as an antiknock fuel additive in the U.S. and Canada. Combustion exhaust gases contain manganese oxides. Manganese oxides are known to cause various deleterious health effects in experimental animals and humans. A field survey of roadside soil and plants in central Utah revealed that soil manganese concentrations in high traffic areas were up to 100-fold higher than historic lead levels. Soil manganese concentrations were highly correlated with distance from the roadway. In addition, roadside aquatic plants were higher in leaf tissue manganese than herbs or grasses. Submerged and emergent aquatic plants were sensitive bioindicators of manganese contamination. Manganese concentrations in soil and in some plant species along impacted roadsides often exceeded levels known to cause toxicity. We conclude that roadside soil and plants were apparently contaminated by manganese oxides from Mn-containing motor vehicle exhaust.
Lytle, C.M.; Smith, B.N.; McKinnon, C.Z. [Brigham Young Univ., Provo, UT (United States)
Catalysts, systems and methods to reduce NOX in an exhaust gas stream
Catalysts, systems and methods are described to reduce NO.sub.x emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having an SCR catalyst comprising silver tungstate on an alumina support. The emissions treatment system may be used for the treatment of exhaust streams from diesel engines and lean burn gasoline engines. An emissions treatment system may further comprise an injection device operative to dispense a hydrocarbon reducing agent upstream of the catalyst.
Castellano, Christopher R. (Ringoes, NJ); Moini, Ahmad (Princeton, NJ); Koermer, Gerald S. (Basking Ridge, NJ); Furbeck, Howard (Hamilton, NJ)
Removal of organic air pollutants from exhaust gases in the trickle-bed bioreactor. Effect of oxygen
The paper describes some reaction engineering fundamentals of the separation of organic air pollutants (volatile organic\\u000a compounds) from waste gases using fixed-bacteria monocultures (biocatalysts) in a trickle-bed reactor. In particular the influence\\u000a of pollutant concentration and oxygen concentration are investigated. The separation efficiency of certain substances such\\u000a as acetone and isopropanol depends strongly on the oxygen concentration. The results obtained
K. Kirchner; S. Wagner; H.-J. Rehm
The impact of using biodiesel/marine gas oil blends on exhaust emissions from a stationary diesel engine.
The purpose of this work was to investigate the impact of marine gas oil (MGO)/biodiesel blends on the exhaust emissions and fuel consumption in a single cylinder, stationary, diesel engine. Three different origins of biodiesel were used as the blending feedstock with the reference MGO, at proportions of 5 and 10% by volume. Methyl esters were examined according to the automotive FAME standard EN 14214. The baseline MGO and biodiesel blends were examined according to ISO 8217:2005 specifications for the DMA category. Independently of the biodiesel used, a decrease of PM, HC, CO and CO(2) emissions was observed. Emissions of NO(x) were also lower with respect to MGO. This reduction in NO(x) may be attributed to some physicochemical properties of the fuels applied, such as the higher cetane number and the lower volatility of methyl esters. Reductions in PM for biodiesel blends were lower in the exhaust than those of the reference fuel which was attributed to the oxygen content and the near absence of sulphur and aromatics compounds in biodiesel. However, a slight increase in fuel consumption was observed for the biodiesel blends that may be tolerated due to the exhaust emissions benefits. Brake thermal efficiency was also determined. Unregulated emissions were characterized by determining the soluble organic fraction content of the particulate matter. PMID:18988104
Karavalakis, G; Tzirakis, E; Mattheou, L; Stournas, S; Zannikos, F; Karonis, D
A well-based cost function and the economics of exhaustible resources: The case of natural gas
A cost function for natural gas production is estimated, using a pool of data from 29 wells. Statistically exact tests are performed for parameter stability across locations, formations, wells, and producing firms. Costs are determined to be inversely related to remaining recoverable reserves, and marginal costs of production are decreasing in all cases. Theoretical implications of these cost characteristics on optimal exhaustible resource extraction are analyzed. Although marginal cost is decreasing, production effects on the resource stock imply that an interior production path may be optimal. Conditions under which production optimally occurs at the capacity bound are delineated, and optimal interior production paths are characterized. 21 refs., 2 tabs.
Chermak, J.M. [Naval Postgraduate School, Monterey, CA (United States)] [Naval Postgraduate School, Monterey, CA (United States); Patrick, R.H. [Rutgers Univ., Newark, NJ (United States)] [Rutgers Univ., Newark, NJ (United States)
Simulation of waste gas pollution diffusion for urban planning: take Nanjing as an example
Waste gas pollution diffusion is one of the basic factors that should be considered in the layout of urban planning. In the field of Chinese urban planning, limited by the planning skill and the level of different departments' involvement, the future pollution degree and pollution range of industrial region is hard to be predicted accurately. The newly issued Urban and
Junting Chen; Jianggang Xu; Yi Qi; Jianghua Tong; Yang Wu
40 CFR 1037.241 - Demonstrating compliance with exhaust emission standards for greenhouse gas pollutants.
...subpart H of this part. (b) Your vehicle family is deemed not to comply if any vehicle configuration in that family has a modeled...deterioration of battery performance for an electric hybrid vehicle. Where the highest useful life...
A Combined Passive Water Vapor Exchanger and Exhaust Gas Diffusion Barrier for Fuel Cell Applications
Fuel cells operating on hydrocarbon fuels require water vapor injection into the fuel stream for fuel reforming and the prevention of carbon fouling. Compared to active water recovery systems, a passive approach would eliminate the need for a separate water source, pumps, and actuators, and thus reduce parasitic thermal losses. The passive approach developed in this paper employs a capillary pump that recovers the water vapor from the exhaust, while providing a diffusion barrier that prevents exhaust gases from entering the fuel stream. Benchtop proof tests have proven the feasibility of the passive fuel humidifier concept, and have provided a calibration factor for a computational design tool that can be used for industrial applications
Williford, Rick E.(BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Hatchell, Brian K.(BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB); Singh, Prabhakar (BATTELLE (PACIFIC NW LAB)) [BATTELLE (PACIFIC NW LAB)
Improving engine efficiency by extracting laser energy from hot exhaust gas
We show that it is possible to improve the efficiency of a classical Otto-cycle heat engine by adding a high-Q microwave cavity and a laser system that can extract coherent laser energy from thermally excited 'exhaust' atoms. This improvement does not violate the second law of thermodynamics, i.e., we show that a combined high-Q microwave cavity and a laser system does not improve the efficiency of a classical Carnot-cycle heat engine.
Rostovtsev, Y.V.; Matsko, A.B.; Nayak, N. [Department of Physics and Institute for Quantum Studies, Texas A and M University, Texas 77843-4242 (United States); Zubairy, M.S. [Department of Physics and Institute for Quantum Studies, Texas A and M University, Texas 77843-4242 (United States); Department of Electronics, Quaid-i-Azam University, Islamabad (Pakistan); Scully, M.O. [Department of Physics and Institute for Quantum Studies, Texas A and M University, Texas 77843-4242 (United States); Department of Electrical Engineering, Texas A and M University, Texas 77843 (United States); Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany)
Significance of platinum group metals emitted from automobile exhaust gas converters for the biosphere
Intention, Goal, Scope, Background��Following the introduction of automobile catalytic converters the platinum group metals (PGM) platinum (Pt), palladium (Pd)\\u000a and rhodium (Rh) gain on increasing interest in environmental research as these metals are emitted with exhaust fumes into\\u000a the environment. Consequently, elevated PGM levels were found in different environmental matrices uch as road dusts, soils\\u000a along heavily frequented roads, sediments
Sonja Zimmermann; Bernd Sures
Catalysts to reduce NO.sub.x in an exhaust gas stream and methods of preparation
Catalysts, systems and methods are described to reduce NO.sub.x emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having a catalyst comprising silver and a platinum group metal on a particulate alumina support, the atomic fraction of the platinum group metal being less than or equal to about 0.25. Methods of manufacturing catalysts are described in which silver is impregnated on alumina particles.
Castellano, Christopher R. (Ringoes, NJ); Moini, Ahmad (Princeton, NJ); Koermer, Gerald S. (Basking Ridge, NJ); Furbeck, Howard (Hamilton, NJ); Schmieg, Steven J. (Troy, MI); Blint, Richard J. (Shelby Township, MI)
Catalysts, systems and methods are described to reduce NO.sub.x emissions of an internal combustion engine. In one embodiment, an emissions treatment system for an exhaust stream is provided having a catalyst comprising silver on a particulate alumina support, the silver having a diameter of less than about 20 nm. Methods of manufacturing catalysts are described in which ionic silver is impregnated on particulate hydroxylated alumina particles.
Koermer, Gerald S. (Basking Ridge, NJ); Moini, Ahmad (Princeton, NJ); Furbeck, Howard (Hamilton, NJ); Castellano, Christopher R. (Ringoes, NJ)
Exhaust Gas Recirculation Cooler Fouling in Diesel Applications: Fundamental Studies Deposit Properties and Microstructure
This paper reports on the results of experimental efforts aimed at improving the understanding of the mechanisms and conditions at play in the fouling of EGR coolers. An experimental apparatus was constructed to utilize simplified surrogate heat exchanger tubes in lieu of full-size heat exchangers. The use of these surrogate tubes allowed removal of the tubes after exposure to engine exhaust for study of the deposit layer and its properties. The exhaust used for fouling the surrogate tubes was produced using a modern medium-duty diesel engine fueled with both ultra-low sulfur diesel and biodiesel blends. At long exposure times, no significant difference in the fouling rate was observed between fuel types and HC levels. Surface coatings for the tubes were also evaluated to determine their impact on deposit growth. No surface treatment or coating produced a reduction in the fouling rate or any evidence of deposit removal. In addition, microstructural analysis of the fouling layers was performed using optical and electron microscopy in order to better understand the deposition mechanism. The experimental results are consistent with thermophoretic deposition for deposit formation, and van der Waals attraction between the deposit surface and exhaust-borne particulate.
Storey, John Morse [ORNL; Sluder, Scott [ORNL; Lance, Michael J [ORNL; Styles, Dan [Ford Motor Company; Simko, Steve [Ford Motor Company
E-Alerts: Environmental pollution and control (air pollution and control). E-mail newsletter
Topics of discussion include the following: Air pollution from flue gases, exhaust gases, odors, dust, smog, microorganisms, etc.; Control techniques and equipment; Sampling and analytical techniques, and equipment; Waste gas recovery; Biological and ecological effects; Air pollution chemistry; Acid precipitation; Atmospheric motion; Laws, legislation, and regulations; Public administration; Economics; Land use.
Characteristics of exhaust gas, liquid products, and residues of printed circuit boards using the pyrolysis process
Introduction��The pyrolytic method was employed to recycle metals and brominated compounds blended into printed circuit boards (PCBs).\\u000a \\u000a \\u000a \\u000a Methods��PCBs were crushed into pieces 4.0�4.8�mm in size, and the crushed pieces were pyrolyzed at temperatures ranging from 200 to\\u000a 500�C. The compositions of pyrolytic residues, liquid products, and exhaust were analyzed by inductively coupled plasma atomic\\u000a emission spectrometer, inductively coupled plasma mass
Hung-Lung Chiang; Cho-Ching Lo; Sen-Yi Ma
78 FR 63015 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...
Federal Register 2010, 2011, 2012, 2013
...Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for Aircraft...amended the emission standards for certain turbine engine powered airplanes to incorporate...The EPA also proposed adopting the gas turbine engine test procedures of the...
78 FR 63017 - Exhaust Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for...
...Emissions Standards for New Aircraft Gas Turbine Engines and Identification Plate for Aircraft...comments amending the emission standards for turbine engine powered airplanes to incorporate...The EPA also proposed adopting the gas turbine engine test procedures of the...
Dynamic characteristics of a hydrostatic gas bearing driven by oscillating exhaust pressure
Vibration of a statically loaded, inherently compensated hydrostatic journal bearing due to oscillating exhaust pressure is investigated. Both angular and radial vibration modes are analyzed. The time-dependent Reynolds equation governing the pressure distribution between the oscillating journal and sleeve is solved together with the journal equation of motion to obtain the response characteristics of the bearing. The Reynolds equation and the equation of motion are simplified by applying regular perturbation theory for small displacements. The numerical solutions of the perturbation equations are obtained by discretizing the pressure field using finite-difference aproximations with a discrete, nonuniform line-source model which excludes effects due to feeding hole volume. An iterative scheme is used to simultaneously satisfy the equations of motion for the journal. The results presented include Bode plots of bearing-oscillation gain and phase for a particular bearing configuration for various combinations of parameters over a range of frequencies, including the resonant frequency. 17 references.
Watkins, C.B.; Eronini, I.E.
Effects of prevaporized fuel on exhaust emissions of an experimental gas turbine combustor
Effects of fuel vaporization on the exhaust emission levels of oxides of nitrogen (NOX), carbon monoxide, total hydrocarbons, and smoke number were obtained in an experimental turbojet combustor segment. Two fuel injector types were used in which liquid ASTM A-1 jet fuel and vapor propane fuel were independently controlled to simulate varying degrees of vaporization. Tests were conducted over a range of inlet-air temperatures from 478 to 700 K (860 to 1260 R), pressures from 4 to 20 atmospheres, and combustor reference velocities from 15.3 to 27.4 m/sec (50 to 90 ft/sec). Converting from liquid to complete vapor fuel resulted in NOX reductions as much as 22 percent and smoke number reductions up to 51 percent.
Norgren, C. T.; Ingebo, R. D.
Market structure and exhaustible resources: The case of natural gas and crude oil in California
Using a dataset of natural gas and crude oil production in the state of California, evidence shows overextraction incentives among market participants that shared a common pool. Due to these incentives the supply of gas and crude oil extraction tends to become more inelastic as the number of firms in the pool increases. Using an instrumental variables estimation of the supply function, the results show that the common pool externality caused an average overproduction rate of 11% and 4% over the 1977--2001 period, in natural gas and crude oil, respectively. These figures imply 1 year and 4 years of additional production for natural gas and crude oil, respectively.
Czastkiewicz, Carolina
Review of homogeneous charge compression ignition (HCCI) combustion engines and exhaust gas recirculation (EGR) effects on HCCI
This paper describes the development in ICE which leads to the new advanced combustion mode named Homogeneous Charge Compression Ignition (HCCI). It explains regarding the theory and working principle of HCCI plus the difference of the process in gasoline and diesel fuelled engines. Many of pioneer and recent research works are discussed to get the current state of art about HCCI. It gives a better indication on the potential of this method in improving the fuel efficiency and emission produced by the vehicles' engine. Apart from the advantages, the challenges and future trend of this technology are also included. HCCI is applying few types of control strategy in producing the optimum performance. This paper looks into Exhaust Gas Recirculation (EGR) as one of the control strategies.
Akma Tuan Kamaruddin, Tengku Nordayana; Wahid, Mazlan Abdul; Sies, Mohsin Mohd
The study of heat transfer for nanofluid with carbon nano particle in an exhaust gas recirculation (EGR) cooler
A carbon nanofluid was adapted to examine the characteristics of its cooling performance in an exhaust gas recirculation (EGR) cooler, compared with that of the usual working fluid water. After steady state, the heat transfer rate of water became nearly constant; however, that of the nanofluid showed a slight increase, suggesting that something happened to the nanofluid. The result shows that the cooling performance of the carbon nanofluid was a little better than that of water; however, its performance data improved with time while those of water were stable. It shows that assembly of the carbon nanoparticles changed with its circulation through the EGR cooler and the shape of the particle assembly depended on the dispersion method employed.
Kim, Seongsoo; Chung, Hanshik; Jeong, Hyomin; Lee, Byungho; Ochirkhuyag, Bayanjargal; Lee, Jehyun; Choi, Heekyu
On-Line Analysis of Organic Compounds in Diesel Exhaust Using Proton-Transfer-Reaction Mass Spectrometry
In this study, diesel exhaust (DE) was measured in real time using a proton-transfer-reaction mass spectrometer (PTR-MS) to determine the effect of an after-treatment catalyst on gas phase volatile organic compounds (VOCs). DE after-treatment catalysts are being designed to reduce the pollutants in exhaust, which contains both particulate matter and gas phase constituents. The PTR-MS can make in-situ real time
Megan V. White; B Tom T. Jobson
Using a dataset of natural gas and crude oil production in the state of California, evidence shows overextraction incentives among market participants that shared a common pool. Due to these incentives the supply of gas and crude oil extraction tends to become more inelastic as the number of firms in the pool increases. Using an instrumental variables estimation of the
Carolina Czastkiewicz
Diesel exhaust particles and airway inflammation
Purpose of review. Epidemiologic investigation has associated traffic-related air pollution with adverse human health outcomes. The capacity ofdiesel exhaust particles (DEP), a major emission source air pollution particle, to initiate an airway inflammation has subsequently been ...
Use of aromatic salts for simultaneously removing SO.sub.2 and NO.sub.x pollutants from exhaust of a combustion system
A method is disclosed for removing pollutants from the exhaust of combustion systems burning fuels containing substantial amounts of sulfur and nitrogen. An exemplary method of the invention involves the formation and reaction of a sorbent comprising calcium benzoate. The calcium benzoate is either dry-sprayed (in the form of a fine powder) or wet-sprayed in an aqueous solution in a high temperature environment such as a combustion chamber. The latter technique is feasible since calcium benzoate is a water-soluble form of calcium. When the dispersed particles of calcium benzoate are heated to a high temperature, the organic benzoate burns off and fine calcium oxide particles are formed. These particles are cenospheric (hollow) and have thin and highly porous walls, thus, affording optimum external and internal accessibility for reacting with toxic gaseous emissions such as SO.sub.2. Further, the combustion of the organic benzoate portion of the sorbent results in the conversion of NO.sub.x to N.sub.2.
Levendis, Yiannis A. (Boston, MA) [Boston, MA; Wise, Donald L. (Belmont, MA) [Belmont, MA
Effect of hydroxy (HHO) gas addition on performance and exhaust emissions in compression ignition engines
In this study, hydroxy gas (HHO) was produced by the electrolysis process of different electrolytes (KOH(aq), NaOH(aq), NaCl(aq)) with various electrode designs in a leak proof plexiglass reactor (hydrogen generator). Hydroxy gas was used as a supplementary fuel in a four cylinder, four stroke, compression ignition (CI) engine without any modification and without need for storage tanks. Its effects on
Ali Can Yilmaz; Erin� Uludamar; Kadir Aydin
Flow development and turbulence length scales within an annular gas turbine exhaust diffuser
This paper presents the experimental investigation of a scaled down model of a PGT10 gas turbine diffuser by Nuovo Pignone S.p.A. The model was designed to operate in geometric and Reynolds number similarity with the GT diffuser, and 24 guide vanes are mounted at inlet to reproduce typical inlet conditions of an industrial gas turbine diffuser. The PGT10 diffuser has
Stefano Ubertini; Umberto Desideri
Ground-water pollution from natural gas and oil production in New York
Natural gas is produced throughout the central and W. part of New York State; whereas, oil production has been limited mainly to Allegheny and Cattaraugus counties. Oil production, and particularly secondary recovery by the water-flooding method, has resulted in pollution of ground- and surface-water supplies with oil and salt water. Pollution from active oil fields has been caused by separator
Selectivity improvement of semi-conducting gas sensors by selective filter for atmospheric pollutants detection
The monitoring of atmospheric pollution using chemical gas sensors is a challenge due to the lack of selectivity of most existing devices. However, their performances can be improved using filtering films achieving the separation or the removal of some gases. This study is focused on the detection of carbon monoxide and of oxidant pollutants (nitrogen dioxide and ozone) by sensors
J. P. Viricelle; A. Pauly; L. Mazet; J. Brunet; M. Bouvet; C. Varenne; C. Pijolat
Presents the material given in one class period in a course on Environmental Studies at Chesterfield School, England. The topics covered include air pollution, water pollution, fertilizers, and insecticides. (JR)
Rowbotham, N.
Improvement of $\\\\hbox{NO}_{\\\\rm x}$ Reduction Efficiency in Diesel Emission Control Using Nonthermal Plasma Combined Exhaust Gas Recirculation Process
Atmospheric-pressure nonequilibrium nonthermal plasma hybrid exhaust gas aftertreatment systems that do not utilize precious metal catalysts, harmful ammonia, etc., have been developed by the authors. Two types of new environmental pro- tection systems (a dry system and a wet system), which enable the production of ultralow CO2, particulate matter and NOx emissions as well as reduced fuel consumption and low
Takuya Kuwahara; Keiichiro Yoshida; Youhei Kannaka; Tomoyuki Kuroki; Masaaki Okubo
On the Performance and Operability of GE�s Dry Low NO x Combustors utilizing Exhaust Gas Recirculation for PostCombustion Carbon Capture
The capture and sequestration of CO2 will be necessary to mitigate CO2 emissions from fossil fuel (coal, oil, natural gas or biomass) power generation facilities in a carbon constrained world. Post combustion carbon capture is a viable technology alternative to reduce CO2 emissions from power plants in the short term. The CO2 concentration in the exhaust gases of natural fired
Andrei T. Evulet; Ahmed M. ELKady; Anthony R. Branda; Daniel Chinn
Investigations in the Carcinogenicity of Diesel-Engine Exhaust-Gas Condensate and with sub-Fractions Implanted into the Lungs of Rats.
The test for the carcinogenetic effect of the hydrophilic fraction (approx. = 25% by weight) and the hydrophobic fraction (approx. = 75% by weight) of the diesel exhaust gas condensate and of sub-fractions of the hydrophobic part was carried through in th...
R. Deutsch-Wenzel H. Brune
Control of combustibility of volatile hydrocarbons and particulate matter in an exhaust gas stream by use of a high velocity burner in a carbon bake ring furnace
The present invention relates to a method of and an apparatus for controlling the combustibility of volatile hydrocarbons and particulate matter in an exhaust gas stream driven off from a carbon product being baked in a furnace. In a prebaking stage, the carbon product is heat treated in a temperature range of 300 to 600° C. In order to drive
F. D. Arnold; C. M. Benton; G. D. Evrad; H. O. Forberg; R. L. Tuscher
Gas-particle partitioning of primary organic aerosol emissions: (1) Gasoline vehicle exhaust
The gas-particle partitioning of the primary organic aerosol (POA) emissions from fifty-one light-duty gasoline vehicles (model years 1987�2012) was investigated at the California Air Resources Board Haagen�Smit Laboratory. Each vehicle was operated over the cold-start unified cycle on a chassis dynamometer and its emissions were sampled using a constant volume sampler. Four independent yet complementary approaches were used to investigate POA gas-particle partitioning: sampling artifact correction of quartz filter data, dilution from the constant volume sampler into a portable environmental chamber, heating in a thermodenuder, and thermal desorption/gas chromatography/mass spectrometry analysis of quartz filter samples. This combination of techniques allowed gas-particle partitioning measurements to be made across a wide range of atmospherically relevant conditions � temperatures of 25�100��C and organic aerosol concentrations of <1�600�?g�m?3. The gas-particle partitioning of the POA emissions varied continuously over this entire range of conditions and essentially none of the POA should be considered non-volatile. Furthermore, for most vehicles, the low levels of dilution used in the constant volume sampler created particle mass concentrations that were greater than a factor of 10 or higher than typical ambient levels. This resulted in large and systematic partitioning biases in the POA emission factors compared to more dilute atmospheric conditions, as the POA emission rates may be over-estimated by nearly a factor of four due to gas-particle partitioning at higher particle mass concentrations. A volatility distribution was derived to quantitatively describe the measured gas-particle partitioning data using absorptive partitioning theory. Although the POA emission factors varied by more than two orders of magnitude across the test fleet, the vehicle-to-vehicle differences in gas-particle partitioning were modest. Therefore, a single volatility distribution can be used to quantitatively describe the gas-particle partitioning of the entire test fleet. This distribution is designed to be applied to quartz filter POA emission factors in order to update emissions inventories for use in chemical transport models.
May, Andrew A.; Presto, Albert A.; Hennigan, Christopher J.; Nguyen, Ngoc T.; Gordon, Timothy D.; Robinson, Allen L.
Effect of Different Catalysts in Hybrid Gas-Liquid Discharge for the Removal of Organic Pollutant
Hybrid gas-liquid discharge technology is a promising water treatment technology. The synergic effect of activated alumina and discharge electric field could accelerate the removal of organic pollutants. Effect of loaded catalysts on the organic pollutant removal rate in hybrid gas-liquid discharge was investigated by loading FeOOH and nanosize TiO2 on the surface of activated alumina particles. The results revealed that
Linan Zhu; Ye Gao; Hui Liu; Jun Ma
[Distribution of a hypoxic gas mixture by retro-pollution of a medical gas distribution system].
The authors report a case of retropollution through the defective gas mixer of a Logic O4T-IMV ventilator (Ohmeda) located in the recovery room. Due to a defective check valve inside the mixer, medical air entered into the oxygen pipeline when the O2 pressure decreased below the pressure inside the medical air pipeline. This incident resulted in episodes of hypoxic gas mixture delivery in the operating theatre, when nitrous oxide was associated with oxygen polluted with medical air. The occurrence of such an incident, rarely described so far, requires the association of several factors. It can be recognized without delay with the continuous use of an oxygen analyser. PMID:7733527
Gorce, P; Crisan, A; Gondret, R; Viallard, M L; Clergue, F
Mutagenicity of diesel engine exhaust is eliminated in the gas phase by an oxidation catalyst but only slightly reduced in the particle phase.
Concerns about adverse health effects of diesel engine emissions prompted strong efforts to minimize this hazard, including exhaust treatment by diesel oxidation catalysts (DOC). The effectiveness of such measures is usually assessed by the analysis of the legally regulated exhaust components. In recent years additional analytical and toxicological tests were included in the test panel with the aim to fill possible analytical gaps, for example, mutagenic potency of polycyclic aromatic hydrocarbons (PAH) and their nitrated derivatives (nPAH). This investigation focuses on the effect of a DOC on health hazards from combustion of four different fuels: rapeseed methyl ester (RME), common mineral diesel fuel (DF), SHELL V-Power Diesel (V-Power), and ARAL Ultimate Diesel containing 5% RME (B5ULT). We applied the European Stationary Cycle (ESC) to a 6.4 L turbo-charged heavy load engine fulfilling the EURO III standard. The engine was operated with and without DOC. Besides regulated emissions we measured particle size and number distributions, determined the soluble and solid fractions of the particles and characterized the bacterial mutagenicity in the gas phase and the particles of the exhaust. The effectiveness of the DOC differed strongly in regard to the different exhaust constituents: Total hydrocarbons were reduced up to 90% and carbon monoxide up to 98%, whereas nitrogen oxides (NO(X)) remained almost unaffected. Total particle mass (TPM) was reduced by 50% with DOC in common petrol diesel fuel and by 30% in the other fuels. This effect was mainly due to a reduction of the soluble organic particle fraction. The DOC caused an increase of the water-soluble fraction in the exhaust of RME, V-Power, and B5ULT, as well as a pronounced increase of nitrate in all exhausts. A high proportion of ultrafine particles (10-30 nm) in RME exhaust could be ascribed to vaporizable particles. Mutagenicity of the exhaust was low compared to previous investigations. The DOC reduced mutagenic effects most effectively in the gas phase. Mutagenicity of particle extracts was less efficiently diminished. No significant differences of mutagenic effects were observed among the tested fuels. In conclusion, the benefits of the DOC concern regulated emissions except NO(X) as well as nonregulated emissions such as the mutagenicity of the exhaust. The reduction of mutagenicity was particularly observed in the condensates of the gas phase. This is probably due to better accessibility of gaseous mutagenic compounds during the passage of the DOC in contrast to the particle-bound mutagens. Concerning the particulate emissions DOC especially decreased ultrafine particles. PMID:22587467
Westphal, G�tz A; Krahl, J�rgen; Munack, Axel; Ruschel, Yvonne; Schr�der, Olaf; Hallier, Ernst; Br�ning, Thomas; B�nger, J�rgen
Methodology for collecting short-period integrated gas samples: estimating acute exposure to woodburning pollution
The concentration of pollutants may fluctuate enormously over the day, making it inappropriate to extrapolate 24-hour averaged pollutant concentration to short-term human exposures of only 1 or 2 hours. A description is given of the design and methodology for collecting integrated gas samples over short periods of time from which the short-term concentrations of woodsmoke aerosol can be deduced. The technique is particularly useful in isolating potential health effects from acute exposure to air pollutants. The method is demonstrated by applying it to acute levels of exposure to pollutants from woodburning stoves and fireplaces in a residential community.
Edgerton, S.A.; Khalil, M.A.K.; Rasmussen, R.A.
Fuel-Air Mixing Apparatus for Reducing Gas Turbine Combustor Exhaust Emissions.
A fuel-air mixer for use in a combustion chamber of a gas turbine engine is provided. The fuel air mixing apparatus comprises an annular fuel injector having a plurality of discrete plain jet orifices, a first swirler wherein the first swirler is located ...
F. J. Zupanc P. R. Yankowich
The 15-volume report summarizes the results of a comprehensive program to quantify methane (CH4) emissions from the U.S. natural gas industry for the base year. The objective was to determine CH4 emissions from the wellhead and ending downstream at the customer's meter. The accur...
On-line exhaust gas analytics during plasma cleaning of PECVD facilities
The etching gases usually applied for plasma supported gas phase cleaning of PECVD facilities, i.e. CF4 SF6 and NF3, were checked for their efficiency with regard to silicon containing layers. Even less known etching gases such as ClF3 or pure fluorine were tested. NF3 has the highest etching rate. The etching rates of F2 and ClF3 are only slightly worse.
Andreas E. Guber; Uwe Koehler
Semiconducting Metal Oxide Based Sensors for Selective Gas Pollutant Detection
A review of some papers published in the last fifty years that focus on the semiconducting metal oxide (SMO) based sensors for the selective and sensitive detection of various environmental pollutants is presented.
Kanan, Sofian M.; El-Kadri, Oussama M.; Abu-Yousef, Imad A.; Kanan, Marsha C.
Gas pollutants removal in a single- and two-stage ejector-venturi scrubber.
The absorption of SO(2) and NH(3) from the flue gas into NaOH and H(2)SO(4) solutions, respectively has been studied using an industrial scale ejector-venturi scrubber. A statistical methodology is presented to characterise the performance of the scrubber by varying several factors such as gas pollutant concentration, air flowrate and absorbing solution flowrate. Some types of venturi tube constructions were assessed, including the use of a two-stage venturi tube. The results showed a strong influence of the liquid scrubbing flowrate on pollutant removal efficiency. The initial pollutant concentration and the gas flowrate had a slight influence. The use of a two-stage venturi tube considerably improved the absorption efficiency, although it increased energy consumption. The results of this study will be applicable to the optimal design of venturi-based absorbers for gaseous pollution control or chemical reactors. PMID:11893424
Gamisans, Xavier; Sarr�, Montserrrat; Lafuente, F Javier
Recommended launch-hold criteria for protecting public health from hydrogen chloride (HC1) gas produced by rocket exhaust
Solid-fuel rocket motors used by the United States Air Force (USAF) to launch missiles and spacecraft can produce ambient-air concentrations of hydrogen chloride (HCI) gas. The HCI gas is a reaction product exhausted from the rocket motor during normal launch or emitted as a result of a catastrophic abort destroying the launch vehicle. Depending on the concentration in ambient air, the HCI gas can be irritating or toxic to humans. The diagnostic and complex-terrain wind field and particle dispersion model used by the Lawrence Livermore National Laboratory`s (LLNL`s) Atmospheric Release Advisory Capability (ARAC) Program was applied to the launch of a Peacekeeper missile from Vandenberg Air Force Base (VAFB) in California. Results from this deterministic model revealed that under specific meteorological conditions, cloud passage from normal-launch and catastropic-abort situations can yield measureable ground-level air concentrations of HCI where the general public is located. To protect public health in the event of such cloud passage, scientifically defensible, emergency ambient-air concentration limits for HCI were developed and recommended to the USAF for use as launch-hold criteria. Such launch-hold criteria are used to postpone a launch unless the forecasted meteorological conditions favor the prediction of safe ground-level concentrations of HCl for the general public. The recommended concentration limits are a 2 ppM 1-h time-weighted average (TWA) concentration constrained by a 1-min 10-ppM average concentration. This recommended criteria is supported by human dose-response information, including data for sensitive humans (e.g., asthmatics), and the dose response exhibited experimentally by animal models with respiratory physiology or responses considered similar to humans.
Daniels, J.I.; Baskett, R.L.
An integrated exhaust gas analysis system with self-contained data processing and automatic calibration
An integrated gas analysis system designed to operate in automatic, semiautomatic, and manual modes from a remote control panel is described. The system measures the carbon monoxide, oxygen, water vapor, total hydrocarbons, carbon dioxide, and oxides of nitrogen. A pull through design provides increased reliability and eliminates the need for manual flow rate adjustment and pressure correction. The system contains two microprocessors to range the analyzers, calibrate the system, process the raw data to units of concentration, and provides information to the facility research computer and to the operator through terminal and the control panels. After initial setup, the system operates for several hours without significant operator attention.
Anderson, R. C.; Summers, R. L.
Photothermal Laser Deflection, an Innovative Technique to Measure Particles in Exhausts.
Photothermal Laser Deflection (PLD) is an analytical technique to measure in real-time the mass concentration of particles and gaseous exhaust pollutants in a variety of combustion devices (e.g., gas turbine engines and rockets). PLD uses a pump laser to ...
C. F. Hess
Dispersion of gas pollutant in a fan-filter-unit (FFU) cleanroom
Numerical simulation and experimental measurement of flow and concentration fields in a working fan-filter-unit (FFU) cleanroom have been conducted in this study. The purpose of the study is to find out the unsteady concentration distribution of a leaking gas pollutant. The standard K�? model was used for the simulation of the flow field. To obtain the gas concentration field, SF6
Sheng-Chieh Chen; Chuen-Jinn Tsai; Shou-Nan Li; Hui-Ya Shih
The report summarizes emission factors for criteria pollutants (NOx, CO, CH4, C2H6, THC, NMHC, and NMEHC) from stationary internal combustion engines and gas turbines used in the natural gas industry. The emission factors were calculated from test results from five test campaigns...
Pollutant Emission Factors from Residential Natural Gas Appliances: A Literature Review
There is a need to reduce air pollutant emissions in some U.S. urban regions to meet federal and state air quality guidelines. Opportunities exist for reducing pollutant emissions from natural gas appliances in the residential sector. A cost-benefit analysis on various pollutant-reducing strategies is needed to evaluate these opportunities. The effectiveness of these pollutant-reducing strategies (e.g., low-emission burners, energy conservation) can then be ranked among themselves and compared with other pollutant-reducing strategies available for the region. A key step towards conducting a cost-benefit analysis is to collect information on pollutant emissions from existing residential natural gas appliances. An extensive literature search was conducted to collect data on residential natural-gas-appliance pollutant emission factors. The literature primarily describes laboratory tests and may not reflect actual emission factor distributions in the field. Pollutant emission factors for appliances operated at over 700 test conditions are summarized for nitrogen oxides, carbon monoxide, fine particulate matter, formaldehyde, and methane. The appliances for which pollutant emissions are summarized include forced-air furnaces; stand-alone space heaters (vented and unvented); water heaters; cooking range burners, ovens, and broilers; and pilot lights. The arithmetic means of the nitrogen oxides and fine particulate matter emission factor distributions agree well with the Environmental Protection Agency published emission factor values for domestic gas appliances (in report AP-42). However, the carbon monoxide and methane distribution means are much higher than the relevant AP-42 values. Formaldehyde emission factors are not addressed in AP-42, but the emission factor mean for formaldehyde is comparable to the AP-42 emission factor value for total hydrocarbon emissions.
Traynor, G.W.; Apte, M.G.; Chang, G.-M.
Numerical Simulation of Exhaust Gas Cooling in Channels with Periodic Elbows for Application in Compact Heat Recovery Systems
Miniature and Micro devices represent the new frontier for advanced heat and mass transfer technology. Due to the small length scales, the use of CFD is very useful for designing and optimizing microfluidic devices since experimentation and visualization at these scales can be difficult. In this work a high temperature air microfluidic cooling strategy for applications such as compact waste heat recovery, exhaust gas recirculation and fuel cell thermal management is proposed. Initially, the application of a simple straight microchannel is considered. In an effort to partially compensate for the poor thermal properties of air, right-angle bends are introduced in order to induce Dean vortices which periodically restart the thermal boundary layer development, thus improving the heat transfer and fluid mixing. Numerical simulations in the range of 100 <= ReDh <= 1000 have been carried out for channels of square cross-section. Channel wall lengths of 1.0 mm are investigated for elbow spacings of 5 mm, 10 mm and 15 mm. High temperature air (300�C) at atmospheric inlet pressure is the working fluid. The results indicate that the elbows substantially improve the local and average heat transfer in the channels while increasing the pressure drop. Design considerations are discussed which take into account the heat transfer and pressure drop characteristics of the channels.
Di Bari, Sergio; Cotton, James S.; Robinson, Anthony J.
The trapping system for the recirculated gases at different locations of the exhaust gas recirculation (EGR) pipe of a homogeneous charge compression ignition (HCCI) engine
Nowadays, in diesel engines, it is typical to recycle exhaust gases (EGR) in order to decrease pollutant emissions. However, few studies report the precisely measured composition of the recycled gases. Indeed, in order to know precisely the composition of the EGR gases, they have to be sampled hot and not diluted, in contrast to the usual practice. Thus, a new system to collect such samples was developed. With this new trapping system, it is possible to measure the concentrations of NOx, CO, CO2, O2, hydrocarbons (HCs) in the range C1-C9, aldehydes, ketones and PAHs. The trapping system and the analytical protocol used are described in this paper.
Piperel, A.; Montagne, X.; Dagaut, P.
One family's air pollution
The author's family pollutes directly or indirectly in five major ways: wastewater discharge; automobile exhaust; home heating oil furnace exhaust; trash disposal; and electricity usage (and the use of other consumer goods whose manufacture and transport caused some level of pollution). He decided to try to quantify how much his family contributed to pollution in one year, 1988. Four sources
Integrated pollutant removal: modeling and experimentation
Experimental and computational work at the Albany Research Center, USDOE is investigating an integrated pollutant removal (IPR) process which removes all pollutants from flue gas, including SOX, NOX, particulates, CO2, and Hg. In combination with flue gas recirculation, heat recovery, and oxy-fuel combustion, the process produces solid, gas, and liquid waste streams. The gas exhaust stream comprises O2 and N2. Liquid streams contain H2O, SOX, NOX, and CO2. Computer modeling and low to moderate pressure experimentation are defining system chemistry with respect to SOX and H2O as well as heat and mass transfer for the IPR process.
Ochs, Thomas L.; Oryshchyn, Danylo B.; Summers, Cathy A.
Infrared (IR) imaging is the best method for detecting leaks of pollutant gases, but current technology based on cooled IR imagers is far too expensive ($75,000 to $150,000) for everyday field use by those who need it to meet regulatory limits�electric and petrochemical ...
Air pollution from ships: Recent developments
All developments on air pollution by ships are fairly recent. Annex VI of the international Marpol-convention, regulating\\u000a the emissions of CFCs, Halons, Volatile Organic Compounds (VOCs) from cargoes, emissions from incinerators and exhaust gas\\u000a emissions from engines (NOx and SOx) entered into force in May 2005. The International Maritime Organization is currently discussing an upgrade of the air pollution\\u000a issues
Alexander P. Burgel
Methodology for collecting short?period integrated gas samples: Estimating acute exposure to woodburning pollution
The concentration of pollutants may fluctuate enormously over the day, making it inappropriate to extrapolate 24?hour averaged pollutant concentration to short?term human exposures of only 1 or 2 hours. We describe the design and methodology for collecting integrated gas samples over short periods of time from which the short?term concentrations of woodsmoke aerosol can be deduced. Our technique is particularly
S. A. Edgerton; M. A. K. Khalil; R. A. Rasmussen
The removal of NO x from a lean exhaust gas using storage and reduction on H 3PW 12O 40�6H 2O
NOx sorption and reduction capacities of 12-tungstophosphoric acid hexahydrate (H3PW12O40�6H2O, HPW) were measured under representative alternating conditions of lean and rich exhaust-type gas mixture. Under lean conditions, the sorption of NOx is large and is equivalent to 37mg of NOx\\/gHPW. Although a part of these NOx remains unreduced, HPW is able to reduce some of the NOx to produce N2
K. Vaezzadeh; C. Petit; V. Pitchon
An original application of the Laser-Induced-Incandescence (LII) technique was set up to quantify soot particles inside the combustion chamber of an optically accessible Direct-Injection Diesel engine. Planar soot concentration and local particle diameter were measured for several Exhaust Gas Recirculation (EGR) rates. The impact of the injection timing on the soot evolution for the highest EGR rate was also studied.
Analysis of the Mid-Infrared Spectrum of the Exhaust Gas From an Atmospheric Pressure Plasma Jet (APPJ) Working With an Argon�Air Mixture
The mid-infrared (IR) absorption spectrum of the exhaust gas of an atmospheric pressure plasma jet operated in Ar with the admixture of 0.1% of air has been monitored in the spectral region from 4000 to 750 cm-1. The absorption features of CO2, CO, NO, NO2, N2O, HNO2, and HNO3 were identified using a Fourier transform IR spectrometer combined with a
Andrei V. Pipa; J�rgen Ropcke
Experimental study of various effects of exhaust gas recirculation (EGR) on combustion and emissions of an automotive direct injection diesel engine
Cooled exhaust gas recirculation (EGR) is a common way to control in-cylinder NOx production and is used on most modern high-speed direct injection (HSDI) diesel engines. However EGR has different effects on combustion and emissions production that are difficult to distinguish (increase of intake temperature, delay of rate of heat release (ROHR), decrease of peak heat release, decrease in O2
Alain Maiboom; Xavier Tauzia; Jean-Fran�ois H�tet
Exhaust purification with on-board ammonia production
A method of ammonia production for a selective catalytic reduction system is provided. The method includes producing an exhaust gas stream within a cylinder group, wherein the first exhaust gas stream includes NOx. The exhaust gas stream may be supplied to an exhaust passage and cooled to a predetermined temperature range, and at least a portion of the NOx within the exhaust gas stream my be converted into ammonia.
Robel, Wade J. (Peoria, IL); Driscoll, James Joshua (Dunlap, IL); Coleman, Gerald N. (Helpston, GB)
Some aspects of the distribution of polycyclic aromatic hydrocarbons (pah) between particles and gas phase from diluted gasoline exhausts generated with the use of a dilution tunnel, and its validity for measurement in ambient air
The composition of particle associated polycyclic aromatic hydrocarbons (PAH) originating from diluted gasoline exhausts is compared with that of ambient air samples. The dilution technique used for sampling of vehicle exhausts generates particles with a PAH profile similar to that of ambient air particles. It is demonstrated that 2-4-ring PAH originating from gasoline-fueled vehicle exhausts are mainly in the gas phase in the urban street environment. In the case of diesel vehicles, a substantial part of the low molecular weight PAH are adsorbed on the exhaust particles.
Westerholm, Roger; Stenberg, Ulf; Alsberg, Tomas
Inhalation of Whole Diesel Exhaust but not Gas-Phase Components Affects In Vitro Platelet Aggregation in Hypertensive Rats
Rationale: Intravascular thrombosis and platelet aggregation are enhanced following exposure to diesel exhaust (DE) and other respirable particulate matter; however, the roles of endothelial and circulating mediators on platelet aggregation remain unclear. We hypothesized that ad...
Method for converting noxious pollutants from flue gas into merchantable by-products
A method is described for removing pollutants from boiler plant flue gases comprising the steps of: (a) exchanging heat between a flue gas which contains SO[sub 2], SO[sub 3] and NO pollutants and a first fluid to cool the flue gas down to a first temperature whereat substantially all SO[sub 3] in the flue gas is combined with H[sub 2]O; (b) condensing the SO[sub 3] and H[sub 2]O from the flue gas as a first condensate; (c) adding a solution containing an ammoniacal substance and a detergent to said flue gas to produce soapsuds and sulfates including ammonium bisulfate; (d) collecting the soap suds and ammonium bisulfate produced after said adding step and the first condensate as a first solution; and (e) separating ammonium bisulfate from said first solution.
Johnson, A.F.
The author's family pollutes directly or indirectly in five major ways: wastewater discharge; automobile exhaust; home heating oil furnace exhaust; trash disposal; and electricity usage (and the use of other consumer goods whose manufacture and transport caused some level of pollution). He decided to try to quantify how much his family contributed to pollution in one year, 1988. Four sources of air pollution were considered and are quantified: car exhausts, home heating oil exhausts, electricity, and trash disposal (through a waste-to-energy plant).
Getz, N.P.
On-road measurement of gas and particle phase pollutant emission factors for individual heavy-duty diesel trucks.
Pollutant concentrations in the exhaust plumes of individual diesel trucks were measured at high time resolution in a highway tunnel in Oakland, CA, during July 2010. Emission factors for individual trucks were calculated using a carbon balance method, in which pollutants measured in each exhaust plume were normalized to measured concentrations of carbon dioxide. Pollutants considered here include nitric oxide, nitrogen dioxide (NO(2)), carbon monoxide, formaldehyde, ethene, and black carbon (BC), as well as optical properties of emitted particles. Fleet-average emission factors for oxides of nitrogen (NO(x)) and BC respectively decreased 30 � 6 and 37 � 10% relative to levels measured at the same location in 2006, whereas a 34 � 18% increase in the average NO(2) emission factor was observed. Emissions distributions for all species were skewed with a small fraction of trucks contributing disproportionately to total emissions. For example, the dirtiest 10% of trucks emitted half of total NO(2) and BC emissions. Emission rates for NO(2) were found to be anticorrelated with all other species considered here, likely due to the use of catalyzed diesel particle filters to help control exhaust emissions. Absorption and scattering cross-section emission factors were used to calculate the aerosol single scattering albedo (SSA, at 532 nm) for individual truck exhaust plumes, which averaged 0.14 � 0.03. PMID:22799607
Dallmann, Timothy R; DeMartini, Steven J; Kirchstetter, Thomas W; Herndon, Scott C; Onasch, Timothy B; Wood, Ezra C; Harley, Robert A
An EGR assembly is disclosed of a sonic flow EGR valve and a fluid pressure actuated servo operated by air pressure modified by an air bleed device controlled in response to changes in carburetor venturi vacuum levels to provide EGR valve openings in proportion to engine air flow increases.
There is disclosed an EGR assembly of a sonic flow EGR valve and a fluid pressure actuated servo operated by air pressure modified by an air bleed device controlled in response to changes in carburetor venturi vacuum levels to provide EGR valve openings in proportion to engine air flow increases.
Functionalized single wall carbon nanotube sensor in a perturbed microwave resonant cavity based toxin\\/pollutant gas pressure sensor
The Vlasov and Maxwell's equations are established and solved numerically to describe the effects of toxin\\/pollutant gas pressure and functionalized single wall carbon nanotube (SWCNT) sensor in a perturbed microwave resonant cavity. The dependence of the absorption coefficient on incident frequency, toxin\\/pollutant gas pressure, electron density, and collision frequency is presented. The numerical results illustrate that the resonant frequency shifts
S. B. Tooski
Chemical analysis and ozone formation potential of exhaust from dual-fuel (liquefied petroleum gas/gasoline) light duty vehicles
Measures must be undertaken to lower the transport sector's contribution to anthropogenic emissions. Vehicles powered by liquefied petroleum gas (LPG) are an option due to their reduced emissions of air pollutants compared to engines with conventional fuels. In the present study, ten different dual-fuel LPG/gasoline light duty vehicles were tested, which all complied with European emission level legislation EURO-4. Tests with LPG and gasoline were performed on a chassis dynamometer by applying the New European Driving Cycle (NEDC) and emission factors and ozone formation potentials of both kinds of fuels were compared. The components investigated comprised regulated compounds, CO 2, volatile hydrocarbons and carbonyls. On-line analysis of aromatic species was carried out by resonance-enhanced multiphoton ionization-time-of-flight mass spectrometry (REMPI-TOFMS). We demonstrate that utilization of LPG can entail some environmental benefits by reducing emissions. However, for dual-fuel LPG/gasoline vehicles running on LPG the benefits are less than expected. The main reason is that dual-fuel vehicles usually start the engine up on gasoline even when LPG is selected as fuel. This cold-start phase is crucial for the quality of the emissions. Moreover, we demonstrate an influence on the chemical composition of emissions of vehicle performance, fuel and the evaporative emission system of the vehicles.
Adam, T. W.; Astorga, C.; Clairotte, M.; Duane, M.; Elsasser, M.; Krasenbrink, A.; Larsen, B. R.; Manfredi, U.; Martini, G.; Montero, L.; Sklorz, M.; Zimmermann, R.; Perujo, A.
Adsorption on carbon and zeolite of pollutants from flue gas during incineration
The volatile organic compound, polycyclic aromatic hydrocarbon, dioxin, and metallic components released from incineration threaten human health. These pollutants, appearing in a molecular state, cannot be effectively removed by baghouse and electrostatic precipitators through capture and filtration mechanisms. Previous studies indicate that activated carbon is conventionally used to remove organic compounds from gas at low temperatures (less than 30 C).
Ming-Yen Wey; Lih-Jyh Yu; Suen-Iou Jou; Bo-Chin Chiang; Ming-Chi Wei
Diesel engine exhaust emissions
According to the results of tests carried out on monorail diesel engines in the Federal Republic of Germany, nitrogen oxides, rather than carbon monoxide, are the most dangerous components of exhaust emissions, and require larger volumes of air to dilute them. The harmful gas concentrations which are measured and the maximum permissible concentrations of the gases exhausted by diesel engines determine the necessary amounts of air by which the fumes are diluted. Opinions on maximum permissible values, especially in the case of nitrogen oxides, and the methods used for determining the amount of air necessary for dilution, vary from country to country. In general, though, only diesel engines which produce extremely small amounts of harmful gases should be used underground. If a diesel engine draws in air containing methane, the concentration of harmful gases emitted in the exhaust fumes varies according to methane content, engine speed, and engine load.
Not Available
Catalyst for the combustion of harmful substances contained in exhaust gases of internal combustion engines operated with alcohol and process for the production of the catalyst
US Patent & Trademark Office Database
A catalyst is disclosed for combustion of pollutants contained in the exhaust gases of internal combustion engines operated with alcohol. The catalyst consists of a metal carrier, a coating deposited on it made of a catalytically active aluminum oxide and an amount of palladium deposited on said coating. A production process for the catalyst is described which provides a final activation in oxidizing atmosphere or a formation in the stream of the exhaust gas that is to be purified at certain temperatures as well as the use of the catalyst for the simultaneous elimination of aldehydes, alcohols, carbon monoxide and hydrocarbons present in the exhaust gas.
An inexpensive imaging Instrument to quickly locate leaks of methane and other greenhouse and VOC gases would reduce the cost and effort expended by industry to comply with EPA regulations. In Phase I, of this WBIR program, a new gas leak visualization camera was demonstrated...
Li - O anti-correlation in NGC 6752: evidence for Li-enriched polluting gas
Context. Elemental correlations and anti-correlations are known to be present in globular clusters (GCs) owing to pollution by CNO cycled gas. Because of its fragility Li is destroyed at the temperature at which the CNO cycling occurs, and this makes Li a crucial study for the nature of the contaminating stars. Aims: We observed 112 un-evolved stars at the Turnoff of the NGC 6752 cluster with FLAMES at the VLT to investigate the presence and the extent of a Li-O correlation. This correlation is expected if there is a simple pollution scenario. Methods: Li (670.8 nm) and O triplet (771 nm) abundances are derived in NLTE. All stars belong to a very narrow region of the color-magnitude diagram, so they have similar stellar parameters (Teff, log g). Results: We find that O and Li correlate, with a high statistical significance that confirms the early results for this cluster. At first glance this is what is expected if a simple pollution of pristine gas with CNO cycled gas (O-poor, Li-poor) occurred. The slope of the relationship, however, is about 0.4, and differs from unity by over 7?. A slope of one is the value predicted for a pure contamination model. Conclusions: We confirm an extended Li-O correlation in non evolved stars of NGC 6752. At the same time the characteristic of the correlation shows that a simple pollution scenario is not sufficient to explain the observations. Within this scenario the contaminant gas must have been enriched in Li. This would rule out massive stars as main polluters, and favor the hypothesis that the polluting gas was enriched by intermediate or high-mass AGB stars, unless the former can be shown to be able to produce Li. According to our observations, the fraction of polluting gas contained in the stars observed is a considerable fraction of the stellar mass of the cluster. Based on observations collected at the ESO VLT. Programme -81.D-0287.
Shen, Z.-X.; Bonifacio, P.; Pasquini, L.; Zaggia, S.
40 CFR 86.109-94 - Exhaust gas sampling system; Otto-cycle vehicles not requiring particulate emission measurements.
...Vehicles and New Light-Duty Trucks and New Otto-Cycle Complete Heavy-Duty Vehicles; Test Procedures § 86.109-94 Exhaust...percent of a temperature change (as measured in hot silicone oil). (3) The pressure measuring system shall have an...
Effect of Exhaust Gas Recirculation (EGR) on the Performance and Emission Characteristics of Diesel Engine with Sunflower Oil Methyl Ester
Transesterified fuels (biodiesel) from vegetable oils are alternative fuels for diesel engines. They are renewable and offer potential reduction in CO and HC emissions due to higher O2 contents in vegetable oil. Many research studies have reported that exhaust from biodiesel fuel has higher NOx emissions while HC and PM emissions are significantly lower than operated with diesel fuel. The
K. Rajan; K. R. Senthilkumar
The objectives of this report period were to complete the development of the Gas Generator design, which was done; fabricate and test of the non-polluting unique power turbine drive gas Gas Generator, which has been postponed. Focus during this report period has been to complete the brazing and bonding necessary to fabricate the Gas Generator hardware, continue making preparations for fabricating and testing the Gas Generator, and continuing the fabrication of the Gas Generator hardware and ancillary hardware in preparation for the test program. Fabrication is more than 95% complete and is expected to conclude in early May 2002. the test schedule was affected by relocation of the testing to another test supplier. The target test date for hot fire testing is now not earlier than June 15, 2002.
An apparatus for treating pollutants in a gas may include a source of hydrogen peroxide, and a treatment injector for creating and injecting dissociated hydrogen peroxide into the flow of gas. The treatment injector may further include an injector housing having an inlet, an outlet, and a hollow interior extending there between. The inlet may be connected in fluid communication with the source of hydrogen peroxide so that hydrogen peroxide flows through the hollow interior and toward the outlet. At least one ultraviolet (UV) lamp may be positioned within the hollow interior of the injector housing. The at least one UV lamp may dissociate the hydrogen peroxide flowing through the tube. The dissociated hydrogen peroxide may be injected into the flow of gas from the outlet for treating pollutants, such as nitrogen oxides.
Cooper, Charles David (Inventor); Clauseu, christian Anthony (Inventor)
Apparatus and method for treating pollutants in a gas using hydrogen peroxide and UV light
An apparatus for treating pollutants in a gas may include a source of hydrogen peroxide, and a treatment injector for creating and injecting dissociated hydrogen peroxide into the flow of gas. The treatment injector may further include an injector housing having an inlet, an outlet, and a hollow interior extending therebetween. The inlet may be connected in fluid communication with the source of hydrogen peroxide so that hydrogen peroxide flows through the hollow interior and toward the outlet. At least one ultraviolet (UV) lamp may be positioned within the hollow interior of the injector housing. The at least one UV lamp may dissociate the hydrogen peroxide flowing through the tube. The dissociated hydrogen peroxide may be injected into the flow of gas from the outlet for treating pollutants, such as nitrogen oxides.
Cooper, Charles David (Inventor); Clausen, Christian Anthony (Inventor)
Predictive Model for Pollutant Dispersion from Gas Flaring: A Case Study of Oil Producing Area of Nigeria
Nigeria has recorded a long history of petroleum exploration, but gas flaring associated with this activity is contributing immensely to air pollution in the Niger-Delta area and beyond. Hence, this work is aimed at quantifying the extent of air pollution from gas flaring, i.e., CO2, CO, SO2, NO2, and THC. Volume of gas flare and conditions of flare as well
A. S. Abdulkareem; J. O. Odigure; S. Abenege
[Passive detection of aeroengine exhaust based on Fourier transform infrared system].
Since the composition and concentration of aeroengine exhaust can reflect the combustion efficiency, they can provide the basis for condition based maintenance, and also the basis for the analysis of environment pollution caused by aeroengine exhaust. So the importance of aeroengine exhaust detection is evident. Up to now, the measurement of aeroengine exhaust is based on sampling analysis which is not convenient and can't meet the detection requirements when an aeroplane is flying-off or flying in the sky. Hence, new methods of exhaust detection must be studied. The passive measurement technology based on Fourier transform infrared spectroscopy (FTIR) was applied to the measurement of aeroengine exhaust in the present paper. At first, the principle of passive measurement based on FTIR was introduced in detail. On this basis, a model algorithm for gas concentration calculation was deduced based on the principle of infrared transmission. Then the feasibility of aeroengine exhaust measurement based on passive FTIR was analyzed, and the passive measurement method of aeroengine exhaust based on FTIR was given. In the end, an experiment of aeroengine exhaust passive measurement was carried out by a FTIR with the type of Tensor 27 produced by BRUKER. Good quality spectra of the exhaust and the background were measured. Based on the model algo rithm of passive measurement, the absorbance spectra of CO and NO were obtained respectively, and the concentrations of CO and NO were figured out. To check up the veracity of this method, a comparison was made with another apparatus. There were only little differences between the results of the two experiments, showing that the passive measurement technology based on FTIR could meet the requirements of aeroengine exhaust detection. PMID:19123394
Li, Shao-cheng; Zuo, Hong-fu; Xia, Qing
Inhaled environmental pollutants have a possible role in modulating the susceptibility of humans to respiratory infections. Diesel exhaust (DE) is a major component of urban air pollution and their effects on pulmonary infections is of great concern. Influenza infections cause ...
Anomalous low�high transition of ceria doped SnO 2 sensors exposed to synthetic automobile exhaust gas
The low�high transition behavior of SnO2-based sensors and the effect of ceria as a major additive are studied. The response of the sensors is studied in the presence of synthetic automobile exhaust gases comprising air and CO and\\/or C2H6 reducing gases (fuel), with different weight ratios of the air and fuel, defined as air-to-fuel ratio. A sharp S-shape transition is
M. Valinasab; A. A. Khodadadi; S. Mohajerzadeh; M. Khaghani
Application of modern online instrumentation for chemical analysis of gas and particulate phases of exhaust at the European Commission heavy-duty vehicle emission laboratory.
The European Commission recently established a novel test facility for heavy-duty vehicles to enhance more sustainable transport. The facility enables the study of energy efficiency of various fuels/scenarios as well as the chemical composition of evolved exhaust emissions. Sophisticated instrumentation for real-time analysis of the gas and particulate phases of exhaust has been implemented. Thereby, gas-phase characterization was carried out by a Fourier transform infrared spectrometer (FT-IR; carbonyls, nitrogen-containing species, small hydrocarbons) and a resonance-enhanced multiphoton ionization time-of-flight mass spectrometer (REMPI-TOFMS; monocyclic and polycyclic aromatic hydrocarbons). For analysis of the particulate phase, a high-resolution time-of-flight aerosol mass spectrometer (HR-TOF-AMS; organic matter, chloride, nitrate), a condensation particle counter (CPC; particle number), and a multiangle absorption photometer (MAAP; black carbon) were applied. In this paper, the first application of the new facility in combination with the described instruments is presented, whereby a medium-size truck was investigated by applying different driving cycles. The goal was simultaneous chemical characterization of a great variety of gaseous compounds and particulate matter in exhaust on a real-time basis. The time-resolved data allowed new approaches to view the results; for example, emission factors were normalized to time-resolved consumption of fuel and were related to emission factors evolved during high speeds. Compounds could be identified that followed the fuel consumption, others showed very different behavior. In particular, engine cold start, engine ignition (unburned fuel), and high-speed events resulted in unique emission patterns. PMID:21126058
Adam, T W; Chirico, R; Clairotte, M; Elsasser, M; Manfredi, U; Martini, G; Sklorz, M; Streibel, T; Heringa, M F; Decarlo, P F; Baltensperger, U; De Santi, G; Krasenbrink, A; Zimmermann, R; Prevot, A S H; Astorga, C
Coke-free dry reforming of model diesel fuel by a pulsed spark plasma at low temperatures using an exhaust gas recirculation (EGR) system
Dry reforming of diesel fuel, an endothermic reaction, is an attractive process for on-board hydrogen/syngas production to increase energy efficiency. For operating this dry reforming process in a vehicle, we can use the exhaust gas from an exhaust gas recirculation (EGR) system as a source of carbon dioxide. Catalytic dry reforming of heavy hydrocarbon is a very difficult reaction due to the high accumulation of carbon on the catalyst. Therefore, we attempted to use a non-equilibrium pulsed plasma for the dry reforming of model diesel fuel without a catalyst. We investigated dry reforming of model diesel fuel (n-dodecane) with a low-energy pulsed spark plasma, which is a kind of non-equilibrium plasma at a low temperature of 523 K. Through the reaction, we were able to obtain syngas (hydrogen and carbon monoxide) and a small amount of C2 hydrocarbon without coke formation at a ratio of CO2/Cfuel = 1.5 or higher. The reaction can be conducted at very low temperatures such as 523 K. Therefore, it is anticipated as a novel and effective process for on-board syngas production from diesel fuel using an EGR system.
Sekine, Yasushi; Furukawa, Naotsugu; Matsukata, Masahiko; Kikuchi, Eiichi
Exhausting Science
NSDL National Science Digital Library
The fume hood: You know what it is, but have you ever used it? And if a safety issue arose, would you know what to do? Unfortunately, fume hoods are frequently included in a science room just for show. Little thought is often given to how they should be used or maintained. It is important for science teachers to understand and regularly inspect fume hoods in their classrooms and laboratories. In this article, the author discusses a few considerations for design, inspection, use, and maintenance of fume hoods in a science lab and classroom. Read on for an "exhaustive" look at this safety device!
Mandt, Douglas
Semiconducting Gas Sensors, Remote Sensing Technique and Internet GIS for Air Pollution Monitoring in Residential and Industrial Areas
This research aims at developing a cost-effective and real time air pollution monitoring system with high reliability and less maintenance that utilizes numerical and air dispersion modeling in conjunction with inexpensive, state-of-the-art gas sensors, remote sensing methodologies, and Internet GIS. Conventional pollution detectors, installed by the Bangkok Pollution Control Department and WO3 sensors are employed for in-situ pollution measurements. The data obtained from the satellites sensors and measurements conducted on ground are used for numerical modeling by "Multiple Regressions" and for air dispersion modeling to investigate air pollutants distribution. The correlation and distribution of the air pollutants values are transferred to wireless GIS network system using Web Map Service for rapid and simultaneous dissemination of information on pollution levels at multiple sites.
Pummakarnchana, O.; Phonekeo, V.; Vaseashta, A.
Urban air pollution source apportionment using a combination of aerosol and gas monitoring techniques
The dominating local and regional sources of gaseous and particulate air pollution in the city of Lund (69,000 inhabitants) in southern Sweden were characterized using a combination of aerosol and gas-phase monitoring techniques. Twelve-hour samples were taken at two stations of both fine and coarse fraction urban aerosols with a stacked filter unit during the four-week measurement campaign in March\\/April
Hans Edner
Exhaust cloud rise and diffusion in the atmosphere
Analytical approach develops physical-mathematical model of rocket engine exhaust cloud rise, growth, and diffusion. Analytic derivations and resultant model apply to hot exhaust cloud study or industrial stack plumes, making work results applicable to air pollution. Model formulations apply to all exhaust cloud types and various atmospheric conditions.
Chandler, M. W.; Chu, R. T.; Thayer, S. D.
SOLID PHASE MICROEXTRACTION: MEASUREMENT OF VOLATILE ORGANIC COMPOUNDS (VOCs) IN DHAKA CITY AIR POLLUTION
A solid phase microextraction (SPME) technique was applied for the sampling of volatile organic compounds (VOCs) in ambient air polluted by two stroke autorickshaw engines and automobile exhausts in Dhaka city, Bangladesh. Analysis was carried out by capillary gas chromatography (GC) and GC-mass spectrometry (MS). The methodology was tested by insitu sampling of an aromatic hydrocarbon mixture gas standard with
A. Hussam; M. Alauddin; A. H. Khan; D. Chowdhury; H. Bibi; M. Bhattacharjee; S. Sultana
The objective of this report period was to continue the development of the Gas Generator design, completion of the hardware and ancillary hardware fabrication and commence the Test Preparations for the testing of the non-polluting unique power turbine driven Gas Generator. Focus during this report period has been on completing the Gas Generator fabrication of hardware and ancillary hardware, and completion of unit closeout brazing and bonding. Because of unacceptable delays encountered in a previously competitively selected test site, CES initiated a re-competition of our testing program and selected an alternate test site. Following that selection, CES used all available resources to make preparations for testing the 10 Mw Gas Generator at the new testing site facilities of NTS at Saugus, CA.
E.W. (Gene) Baxter
A portable Fourier transform infrared gas analyzer with a photoacoustic detector performed reliably during pollution prevention research at two industrial facilities. It exhibited good agreement (within approximately 6%) with other analytical instruments (dispersive infrared and ...
46 CFR 119.430 - Engine exhaust pipe installation.
...come in contact with an exhaust pipe. (b) Exhaust gas must...normal conditions. (d) Pipes used for wet exhaust lines...the action of oil, acid, and heat, and has a wall thickness...practicable. (f) Where an exhaust pipe passes through a...
46 CFR 182.430 - Engine exhaust pipe installation.
...come in contact with an exhaust pipe. (b) Exhaust gas must...normal conditions. (d) Pipes used for wet exhaust lines...the action of oil, acid, and heat, has a wall thickness sufficient...practicable. (f) Where an exhaust pipe passes through a...
Exhaust particle removing system for an internal combustion engine
An exhaust particle removing system is described for an internal combustion engine, comprising: (a) a filter disposed in an engine exhaust passage for trapping particles suspended in exhaust gas; (b) a burner for burning off the particles deposited on the filter; (c) means for sensing the pressure in the exhaust passage at a point upstream of the filter; (d) means
Carbon dioxide production from combustion exhaust gases with nitrogen and argon by-product recovery
This patent describes a method for producing carbon dioxide and nitrogen from combustion exhaust gas containing less than about 10% oxygen by weight. It comprises treating the exhaust gas to remove particulate matter; compressing the exhaust gas to a pressure in the range from about 25 psia to about 200 psia; purifying the exhaust gas to remove trace contaminants; separating
R. Krishnamurthy; M. J. Andrecovich
The Vlasov and Maxwell�s equations are established and solved numerically to describe the effects of toxin\\/pollutant gas pressure and functionalized single wall carbon nanotube (SWCNT) sensor in a perturbed microwave resonant cavity. The dependence of the absorption coefficient on incident frequency, toxin\\/pollutant gas pressure, electron density, and collision frequency is presented. The numerical results illustrate that the resonant frequency shifts
Diesel exhaust aftertreatment 1996
The papers in this volume deal in the main with the two most common forms of aftertreatment technology. The first is the trap oxidizer, which is a system for trapping and filtering the particulate matter from the exhaust gas and periodically removing it by thermal oxidation. This process is commonly known as regeneration. The second is the diesel oxidation catalyst. Similar in many ways to the flow through a converter in passenger cars, it oxidizes the soluble organic fraction of the diesel exhaust as well as gaseous hydrocarbons and carbon monoxide. This catalyst is being used in production volumes in heavy duty trucks in the US beginning in 1994. Several papers in this volume deal with the development experience of this converter application. There also is included a series of papers by trap and filter manufacturers dealing with improved materials, making their devices more durable. Papers have been processed separately for inclusion on the data base.
The objective of this report period was to continue the development of the Gas Generator design, fabrication and test of the non-polluting unique power turbine drive Gas Generator. Focus during this past report period has been to continue completion the Gas Generator design, completing the brazing and bonding experiments to determine the best method and materials necessary to fabricate the Gas Generator hardware, continuing to making preparations for fabricating and testing this Gas Generator and commencing with the fabrication of the Gas Generator hardware and ancillary hardware. Designs have been completed sufficiently such that Long Lead Items [LLI] have been ordered and upon arrival will be readied for the fabrication process. The keys to this design are the platelet construction of the injectors that precisely measures/meters the flow of the propellants and water all throughout the steam generating process and the CES patented gas generating cycle. The Igniter Assembly injector platelets fabrication process has been completed and bonded to the Igniter Assembly and final machined. The Igniter Assembly is in final assembly and is being readied for testing in the October 2001 time frame. Test Plan dated August 2001, was revised and finalized, replacing Test Plan dated May 2001.
A comparative study of the elemental composition of the exhaust emissions of cars powered by liquefied petroleum gas and unleaded petrol
Elements emitted from the exhausts of new Ford Falcon Forte cars powered by unleaded petrol (ULP) and liquefied petroleum gas (LPG) were measured on a chassis dynamometer. The measurements were carried out in February, June and August 2001, and at two steady state driving conditions (60 and 80 km h -1). Thirty seven elements were quantified in the exhaust samples by inductively coupled plasma mass spectrometry (ICPMS). The total emission factors of the elements from the exhausts of ULP cars were higher than those of LPG cars at both engine speeds even though high variability in the exhaust emissions from different cars was noted. The effect of the operating conditions such as mileage of the cars, engine speed, fuel and lubricating oil compositions on the emissions was studied. To investigate the effects of these conditions, multivariate data analysis methods were employed including exploratory principal component analysis (PCA), and the multi-criteria decision making methods (MCDM), preference ranking organization method for enrichment evaluation (PROMETHEE) and geometrical analysis for interactive aid (GAIA), for ranking the cars on the basis of the emission factors of the elements. PCA biplot of the complete data matrix showed a clear discrimination of the February, June and August emission test results. In addition, (i) platinum group elements (PGE) emissions were separated from each other in the three different clusters viz. Pt with February, Pd with June and Rh with August; (ii) the motor oil related elements, Zn and P, were particularly associated with the June and August tests (these vectors were also grouped with V, Al and Cu); and (iii) highest emissions of most major elements were associated with the August test after the cars have recorded their highest mileage. Extensive analysis with the aid of the MCDM ranking methods demonstrated clearly that cars powered by LPG outperform those powered by ULP. In general, cars tested in June perform better than those tested in August, which suggested that mileage was the key criterion of car performance on the basis of elemental emission factors.
Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia; Ristovski, Zoran D.; Jayaratne, E. Rohan; Kokot, Serge
Identification and quantification of mixed air pollutants based on homotopy method for gas sensor array.
Accurate recognition of air pollutants and estimation of their concentrations are critical for human health and safety monitoring and can be achieved using gas sensor arrays. In this paper, an efficient method based on a homotopy algorithm is presented for the analysis of sensor arrays responding to binary mixtures. The new method models the responses of a gas sensor array as a system of nonlinear equations and provides a globally convergent way to find the solution of the system. Real data measurement for CH4 and SO2 are used to model sensor responses. The model is applied to the method for prediction and it shows the prediction results are within 1% variation of true values for both gas models. PMID:23366859
Yang, Yuning; Mason, Andrew J
The volatile organic compound, polycyclic aromatic hydrocarbon, dioxin, and metallic components released from incineration threaten human health. These pollutants, appearing in a molecular state, cannot be effectively removed by baghouse and electrostatic precipitators through capture and filtration mechanisms. Previous studies indicate that activated carbon is conventionally used to remove organic compounds from gas at low temperatures (less than 30 C). However, the adsorption characteristics of organic compounds from a gas phase at high temperatures (over 120 C) are seldom mentioned. Moreover, the complex compositions of flue gas cause the adsorption characteristics of organic compounds and heavy metals on adsorbent tubes to be more complicated. This research examines the adsorption characteristics of organic compounds and heavy metals at various incineration conditions. The evaluated parameters include: (1) the operating temperatures; (2) the characteristics of adsorbents (activated carbon and zeolite); and (3) waste compositions and the presence of heavy metals. The results indicate that activated carbon has a high adsorption capacity compared with zeolite.
Wey, M.Y.; Yu, L.J.; Jou, S.I.; Chiang, B.C. [Chung-Hsing Univ., Taichung (Taiwan, Province of China). Dept. of Environmental Engineering] [Chung-Hsing Univ., Taichung (Taiwan, Province of China). Dept. of Environmental Engineering; Wei, M.C. [Chung-Tai Inst. of Health Science and Technology (Taiwan, Province of China)] [Chung-Tai Inst. of Health Science and Technology (Taiwan, Province of China)
Remote passive detection of aircraft exhausts at airports
Emissions from vented sources are often important inputs for the development of emission inventories and contribute to local air pollution and global enhancement of greenhouse gases. Aircraft engines are part of these emission sources. A passive measurement technique such as FTIR emission spectrometry is more cost effective and faster in operation for the determination of the composition of hot exhausts of this kind than other measurement systems as e.g. in situ techniques. Within the scope of aircraft emission investigations the measurements were performed from a measurement van which is equipped with an FTIR spectrometer of high spectral resolution coupled with a telescope and a two-axis movable mirror for rapid orientation towards the emission sources. At airports the emission indices of CO2, CO and NO of main engines and auxiliary power units of standing aircraft were determined. The measurement time is about one minute. The accuracy is better than 30 % as found from burner experiments with calibration gases (CO and NO). The method is also applied to detect exhausts of flares and smoke stacks. Currently, a new scanning FTIR-system is developed. The system allows imaging of the exhaust gas and rapid automated alignment of the field of view. The goal of the new development is to measure aircraft exhausts during normal operations at the airport. The spectrometer is coupled with a camera giving an image of the scenery so that a rapid selection of the hottest exhaust area is possible. It is planned to equip the system with an infrared camera for automatic tracking of this area with the scanning mirror so that measurements of the exhausts of a moving aircraft are possible.
Schaefer, Klaus P.; Jahn, Carsten; Harig, Roland; Aleyt, Christian; Rusch, Peter
40 CFR 86.1309-90 - Exhaust gas sampling system; Otto-cycle and non-petroleum-fueled engines.
...sampling system; Otto-cycle and non-petroleum-fueled engines. 86.1309-90...sampling system; Otto-cycle and non-petroleum-fueled engines. (a)(1) General...gasoline-fueled, natural gas-fueled, liquefied petroleum gas-fueled or...
Sequestration of flue gas CO? by direct gas-solid carbonation of air pollution control system residues.
Direct gas-solid carbonation reactions of residues from an air pollution control system (APCr) were conducted using different combinations of simulated flue gas to study the impact on CO? sequestration. X-ray diffraction analysis of APCr determined the existence of CaClOH, whose maximum theoretical CO? sequestration potential of 58.13 g CO?/kg APCr was calculated by the reference intensity ratio method. The reaction mechanism obeyed a model of a fast kinetics-controlled process followed by a slow product layer diffusion-controlled process. Temperature is the key factor in direct gas-solid carbonation and had a notable influence on both the carbonation conversion and the CO? sequestration rate. The optimal CO? sequestrating temperature of 395 �C was easily obtained for APCr using a continuous heating experiment. CO? content in the flue gas had a definite influence on the CO? sequestration rate of the kinetics-controlled process, but almost no influence on the final carbonation conversion. Typical concentrations of SO? in the flue gas could not only accelerate the carbonation reaction rate of the product layer diffusion-controlled process, but also could improve the final carbonation conversion. Maximum carbonation conversions of between 68.6% and 77.1% were achieved in a typical flue gas. Features of rapid CO? sequestration rate, strong impurities resistance, and high capture conversion for direct gas-solid carbonation were proved in this study, which presents a theoretical foundation for the applied use of this encouraging technology on carbon capture and storage. PMID:23181908
Tian, Sicong; Jiang, Jianguo
Applications of optical measurement technology in pollution gas monitoring at thermal power plants
This paper presents the work of using advanced optical measurement techniques to implement stack gas emission monitoring and process control. A system is designed to conduct online measurement of SO2/NOX and mercury emission from stacks and slipping NH3 of de-nitrification process. The system is consisted of SO2/NOX monitoring subsystem, mercury monitoring subsystem, and NH3 monitoring subsystem. The SO2/NOX monitoring subsystem is developed based on the ultraviolet differential optical absorption spectroscopy (UV-DOAS) technique. By using this technique, a linearity error less than +/-1% F.S. is achieved, and the measurement errors resulting from optical path contamination and light fluctuation are removed. Moreover, this subsystem employs in situ extraction and hot-wet line sampling technique to significantly reduce SO2 loss due to condensation and protect gas pipeline from corrosion. The mercury monitoring subsystem is used to measure the concentration of element mercury (Hg0), oxidized mercury (Hg2+), and total gaseous mercury (HgT) in the flue gas exhaust. The measurement of Hg with a low detection limit (0.1?g/m3) and a high sensitivity is realized by using cold vapor atom fluorescence spectroscopy (CVAFS) technique. This subsystem is also equipped with an inertial separation type sampling technique to prevent gas pipeline from being clogged and to reduce speciation mercury measurement error. The NH3 monitoring subsystem is developed to measure the concentration of slipping NH3 and then to help improving the efficiency of de-nitrification. The NH3 concentration as low as 0.1ppm is able to be measured by using the off-axis integrated cavity output spectroscopy (ICOS) and the tunable diode laser absorption spectroscopy (TDLAS) techniques. The problem of trace NH3 sampling loss is solved by applying heating the gas pipelines when the measurement is running.
Wang, Jian; Yu, Dahai; Ye, Huajun; Yang, Jianhu; Ke, Liang; Han, Shuanglai; Gu, Haitao; Chen, Yingbin
Estimation of odour intensity of indoor air pollutants from building materials with a multi-gas sensor system
This study shows an approach to estimate odour intensity in an indoor environment with a multi-gas sensor system. The sensor system uses 38 non-specific gas sensors, each of which responds to a wide range of different volatile compounds. Due to the complexity of indoor air pollution, the study focuses on emissions of building products as one of the major contributors
Frank Bitter; Birgit M�ller; Dirk M�ller
Compressor noise control begins with design--Part 2. [Noise pollution control for natural gas pipeline compressor stations
Reduction of noise pollution at gas compressor stations associated with natural gas pipelines and distribution systems, has long been a complex problem. Specified noise levels of individual components tell nothing of the overall system when it is installed and placed in a site-specific setting. Further, testing for compliance performance guarantees is virtually impossible to conduct at a distant location because
Feasibility study: Fuel parameters and modifications for exhaust emission control of gas-fired prime movers. Final report, September 1991-March 1992
The initial part of the report examines NOx emissions of gas turbine engines as a function of the gas composition. Natural gases of different non-methane hydrocarbon content are examined, as well as gases of different nitrogen and carbon dioxide contents. NOx emissions are predicted by using the EQLNOX computer code, and comparisons are shown to field data. The balance of the report examines the feasibility of nitrogen injection for the reduction of NOx emissions of gas turbine engines. Two engine sizes are considered: 3.3 and 10MW. Three methods of continuous production of the nitrogen, at the engine site, are considered: membranes, pressure swing adsorption, and the exhaust of a rich-burn piston engine. Seventy percent reduction of the NOx is found to be feasible. The cost in US dollars per ton of NOx removed is 1800 to 4800, depending on the engine size and method. For comparison, the cost of water injection, with the water transported to the site, is 3000 to 5300.
Steele, R.C.; Lai, J.Y.; Malte, P.C.
Anti-air pollution & energy conservation system for automobiles using leaded or unleaded gasoline, diesel or alternate fuel
Exhaust gases from an internal combustion engine operating with leaded or unleaded gasoline or diesel or natural gas, are used for energizing a high-speed gas turbine. The convoluting gas discharge causes a first separation stage by stratifying of heavier and lighter exhaust gas components that exit from the turbine in opposite directions, the heavier components having a second stratifying separation in a vortex tube to separate combustible pollutants from non-combustible components. The non-combustible components exit a vortex tube open end to atmosphere. The lighter combustible, pollutants effected in the first separation are bubbled through a sodium hydroxide solution for dissolving the nitric oxide, formaldehyde impurities in this gas stream before being piped to the engine air intake for re-combustion, thereby reducing the engine's exhaust pollution and improving its fuel economy. The combustible, heavier pollutants from the second separation stage are piped to air filter assemblies. This gas stream convoluting at a high-speed through the top stator-vanes of the air filters, centrifugally separates the coalescent water, aldehydes, nitrogen dioxides, sulfates, sulfur, lead particles which collect at the bottom of the bowl, wherein it is periodically released to the roadway. Whereas, the heavier hydrocarbon, carbon particles are piped through the air filter's porous element to the engine air intake for re-combustion, further reducing the engine's exhaust pollution and improving its fuel economy.
Bose, Ranendra K. (14346 Jacob La., Centreville, VA 20120-3305)
[Defective gas mixers, a cause of retro-pollution of medical gas distribution pipelines].
A defective Air/O2 mixer of a ventilator located downstream of the gas outlets of two pipelines is a potential cause of retropollution. Retropollution of O2 with Air or vice versa carries a risk of either a) a hypoxic gas mixture delivery during anaesthesia, including O2-N2O administration, when the O2 pipeline supplies Air instead of O2, or b) a hyperoxic gas mixture delivery in the intensive therapy unit for neonates during administration of a O2-Air mixture, when the Air pipeline supplies O2 instead of Air. A defective O2/N2O flowmeter-mixer of an anaesthesia machine, with N2O flow control by O2 through a differential pressure manometer, can cause retropollution of O2 supply pipeline with N2O or vice versa. The prerequisite for retropollution is the association of three events: build-up of a pressure difference between the two gas lines; defective or absent back-flow check value in the circuit of the gas at a lower pressure; one of the following defects: a) the pressure equilibrating valves of the mixer cannot amend the pressure difference and allow a gas reflow at the gas mixture outlet; b) leak in the diaphragm of a pressure equilibrating valve; c) defective bypass supply valve. The optimal means for the recognition of a pipeline contamination by another gas is the O2 analyzer, especially in anaesthetic areas where the presence of N2O and Air carries the risk of a hypoxic gas mixture delivery. The mixer or flowmeter-mixer responsible for retropollution can be recognized in plunging successively the various quick couplers underwater into a glass, while the others remain connected to their outlets and the mixer set at a O2 concentration of 50 vol% or the flowmeters set at a similar flow. In case of retropollution, the gas reflow produces bubbles. It is recommended: a) in anaesthetic areas to set the O2 pressure at about 0.2 bar above that of Air and the latter at a pressure of about 0.2 bar above that of N2O; b) in intensive therapy units for neonates, to set the Air pressure at about 0.2 bar above that of O2; c) in all areas to disconnect from the gas outlets the devices equipped with a mixer or a flowmeter-mixer when not in use. PMID:9686101
Otteni, J C; Ancellin, J; Cazala�, J B
Gaseous SO 3 and H 2SO 4 in the exhaust of an aircraft gas turbine engine: measurements by CIMS and implications for fuel sulfur conversion to sulfur (VI) and conversion of SO 3 to H 2SO 4
An estimation of the conversion efficiency ( ?) of fuel sulfur to SO 3 and H 2SO 4, where ?=([SO 3]+[H 2SO 4])/[S T] and [S T] is the total sulfur atom concentration in the exhaust at the exit of an aircraft gas-turbine combustor, was derived from measurements by comparison with model results. The major results of the presented CIMS experiments and their interpretation with a model simulation are: (i) The efficiency is ?=2.3�1% at an exhaust age of about 5 ms from the combustor exit; (ii) The SO 3 molecules represent a major fraction of sulfur (VI) gases ?A<50% and an essential SO 3-conversion to H 2SO 4 takes place in the sampling line where the exhaust gases spend a sufficiently long time and where the temperature is lower than in the hot exhaust. The coincidence of ? from our work (measurements with the sampling point in the exhaust just behind the combustor exit) and ? the measurements in an exhaust at a plume age of about 1 s suggests that the sulfur (VI) formation is inefficient in the post-combustor flow inside the aircraft engine.
Sorokin, A.; Katragkou, E.; Arnold, F.; Busen, R.; Schumann, U.
A Method for the Removal of Sulfur Dioxide from Exhaust Gas Utilizing Pulsed Streamer Corona for Electron Energization
The performance of a new method using pulsed streamer corona for the removal of SO2 from humid air has been evaluated. The pulsed streamer corona produces energetic free electrons that excite, dissociate, and ionize gas molecules, forming radicals that enhance the gas-phase chemical reactions that convert SO2 to acid mist and\\/or particulate aerosols. The aerosols are then collected by conventional
Akira Mizuno; J. Sidney Clements; Robert H. Davis
Toxicity of Engine Exhaust Gases Diesel-Bromochloromethane Fuel Blend.
A single cylinder diesel engine was used to generate exhaust gases formed during the combustion of diesel fuel containing five percent by vol bromochloromethane, as a fuel additive. An exhaust gas dilution system permitted exposure of selected animal spec...
A. A. Johnston K. Springer D. Johnson D. Boenig F. Newman
Fate of hazardous air pollutants in oxygen-fired coal combustion with different flue gas recycling.
Experiments were performed to characterize transformation and speciation of hazardous air pollutants (HAPs), including SO(2)/SO(3), NO(x), HCl, particulate matter, mercury, and other trace elements in oxygen-firing bituminous coal with recirculation flue gas (RFG) from 1) an electrostatic precipitator outlet or 2) a wet scrubber outlet. The experimental results showed that oxycombustion with RFG generated a flue gas with less volume and containing HAPs at higher levels, while the actual emissions of HAPs per unit of energy produced were much less than that of air-blown combustion. NO(x) reduction was achieved in oxycombustion because of the elimination of nitrogen and the destruction of NO in the RFG. The elevated SO(2)/SO(3) in flue gas improved sulfur self-retention. SO(3) vapor could reach its dew point in the flue gas with high moisture, which limits the amount of SO(3) vapor in flue gas and possibly induces material corrosion. Most nonvolatile trace elements were less enriched in fly ash in oxycombustion than air-firing because of lower oxycombustion temperatures occurring in the present study. Meanwhile, Hg and Se were found to be enriched on submicrometer fly ash at higher levels in oxy-firing than in air-blown combustion. PMID:22439940
Zhuang, Ye; Pavlish, John H
Investigations on emission characteristics of the pongamia biodiesel�diesel blend fuelled twin cylinder compression ignition direct injection engine using exhaust gas recirculation methodology and dimethyl carbonate as additive
Experiments were carried out on a twin cylinder direct injection compression ignition engine using pongamia biodiesel�diesel blend as fuel with exhaust gas recirculation (EGR) and dimethyl carbonate (DMC) as additive. The experimental results showed that pongamia biodiesel�diesel blend fuelled engine with EGR and DMC can simultaneously reduce smoke and nitric oxide (NOx) emission. The NOx emission was reduced by about
M. Pandian; S. P. Sivapirakasam; M. Udayakumar
A survey of laser and selected optical systems for remote measurement of pollutant gas concentrations
Applications of the Differential Absorption Lidar (DIAL) technique to the remote sensing of pollutant gases are surveyed. In the DIAl technique, the differential absorption of two laser beams reflected back to a receiver from a target determines the concentration of the gas being studied. The types of instruments available are considered in detail: dye lidar (to measure nitrogen dioxide, sulfur dioxide, and ozone); carbon dioxide laser (for ozone, ethylene, ammonia, and hydrazine), helium-neon laser (for methane); hydrogen fluoride laser (for HF); and tunable diode laser (for nitric oxide and carbon monoxide). DIAL instruments are compared with other optical remote sensors such as Fourier-transform infrared spectrometers, correlation spectrometers (COSPEC and GASPEC), and grating spectrometers; and criteria for the selection of an appropriate gas measuring system are suggested. Laser and other optical remote sensors are found to be cost effective in many cases, despite the fact that they are more costly than point-monitoring systems.
Grant, W. B.; Menzies, R. T.
Comprehensive two-dimensional gas chromatography in the screening of persistent organohalogenated pollutants in environmental samples.
Separations of eight persistent organohalogenated classes of pollutants, organochlorinated pesticides (OCPs), polychlorinated biphenyls (PCBs), polychlorinated diphenyl ethers (PBDEs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychlorinated naphthalenes (PCNs), polychlorinated terphenyls (PCTs) and toxaphene (CTT) by comprehensive two-dimensional gas chromatography (GC x GC) were evaluated. Columns with different polarity and selectivity, including ZB-5, HT-8, DB-17 and BP-10, were selected as first dimension and combined with columns of increasing polarity in the second dimension, i.e. HT-8, BPX-50 and Carbowax (or Supelcowax-10). In total nine column combinations were tested. Because the main interest of the study was fast screening of the test xenobiotic families in complex matrices, in all cases, attention was primarily focussed on group-type separation. Nevertheless, within-group separation was also considered, especially for those classes containing particularly toxic congeners, such as PCBs and PCDD/Fs. Although none of the assayed column sets allowed the simultaneous and complete separation of all pollutants classes, some column combinations provided satisfactory separations among selected families and the rest of pollutants investigated. That was, for instance, the case of HT-8 x BPX-50 for PBDEs and PCDD/Fs, DB-17 x HT-8 for PCNs and OCPs and BP-10 x BPX-50 for CTT, PCDD/Fs and PBDEs. The feasibility of the proposed approach for the fast screening of the target classes of pollutants in complex samples was illustrated by the analysis of food and marine fat samples prepared using simplified miniaturised sample treatment methods. PMID:18160072
Bordajandi, L R; Ramos, J J; Sanz, J; Gonz�lez, M J; Ramos, L
The dominating local and regional sources of gaseous and particulate air pollution in the city of Lund (69,000 inhabitants) in southern Sweden were characterized using a combination of aerosol and gas-phase monitoring techniques. Twelve-hour samples were taken at two stations of both fine and coarse fraction urban aerosols with a stacked filter unit during the four-week measurement campaign in March/April 1993. The aerosol samples were analysed with PIXE for 14 major and trace elements. In addition, gaseous species (SO 2, NO 2, O 3) were measured simultaneously with the DOAS technique over two stretches, crossing each other only 300 m from the downtown aerosol sampling site. The combined results obtained by the analytical techniques PIXE and DOAS for aerosol and gas measurements, respectively, were used in an absolute receptor model in order to identify the major sources affecting the measurement sites and to apportion the measured air pollutants to the identified sources. The gases (SO 2, NO 2, O 3) could also be attributed to specific sources by combining the trace elemental concentration data for the fine fraction aerosol with that of the gaseous species in the receptor model. According to the absolute principal component analysis (APCA) model, the dominant sources for the measured species were resuspended road dust, automobile and diesel emissions, combustion of oil and coal, ferrous and non-ferrous smelters and sea spray. Of these, the sources related to traffic are mainly local in character while the others constitute a regional background. For a small city in southern Scandinavia like Lund with only light industry, the long-range transported air pollutants make up a significant part of the fine fraction aerosol.
Swietlicki, Erik; Puri, Sanjiv; Hansson, Hans-Christen; Edner, Hans
The report summarizes coal gasification and clean-up technology with emphasis on methods of producing a clean industrial fuel gas as defined by agreement for study purposes. The coal-derived industrial fuel discussed produces no more than 0.5 lb of SO2, 0.4 lb of NOx, and 0.1 lb ...
Vehicle exhaust catalysis: I. The relative importance of catalytic oxidation, steam reforming and water-gas shift reactions
The activity of a monolithic three-way catalyst has been compared with the performance of the individual metals (Pt, Pd, Rh) for oxidation, steam reforming and water-gas shift. The presence of ceria was found to accelerate the last two reactions. The orders of activity were found to be: oxidation � presence or absence of ceria, Pt > Pd > three-way >
B. I. Whittington; C. J. Jiang; D. L. Trimm
NOx Abatement in Natural Gas Combustion Exhaust Gases by Solid State Electrochemical Technology. Topical Report September 1986-May 1987,
Solid-state electrochemical technology, embodied in the IGR deNOx process is used to reduce nitrogen oxides (NOx) to nitrogen and oxygen, and thereby control NOx emissions from natural gas powered engines. The IGR deNOx process is based on solid-state, fl...
M. Neyman L. Siwajek W. J. Cook A. Z. Gordon
Fast automotive diesel exhaust measurement using quantum cascade lasers
Step by step, US and European legislations enforce the further reduction of atmospheric pollution caused by automotive exhaust emissions. This is pushing automotive development worldwide. Fuel efficient diesel engines with SCRtechnology can impede NO2-emission by reduction with NH3 down to the ppm range. To meet the very low emission limits of the Euro6 resp. US NLEV (National Low Emission Vehicle) regulations, automotive manufacturers have to optimize continuously all phases of engine operation and corresponding catalytic converters. Especially nonstationary operation holds a high potential for optimizing gasoline consumption and further reducing of pollutant emissions. Test equipment has to cope with demanding sensitivity and speed requirements. In the past Fraunhofer IPM has developed a fast emission analyzer called DEGAS (Dynamic Exhaust Gas Analyzer System), based on cryogenically cooled lead salt lasers. These systems have been used at Volkswagen AG`s test benches for a decade. Recently, IPM has developed DEGAS-Next which is based on cw quantum cascade lasers and thermoelectrically cooled detectors. The system is capable to measure three gas components (i.e. NO, NO2, NH3) in two channels with a time resolution of 20 ms and 1 ppm detection limits. We shall present test data and a comparison with fast FTIR measurements.
Herbst, J.; Brunner, R.; Lambrecht, A.
Development of a Simple Auto Exhaust Analyzer.
A laboratory evaluation was completed regarding the feasibility of applying a heated filament, combustible gas detector to the separate measurement of total hydrocarbons and carbon monoxide in auto exhaust. Of the several candidate filament materials test...
L. Hiam S. Chaikin
Exhaust support system
An exhaust support system is described for a midship engine rear wheel drive-type vehicle having a transversely mounted engine, which consists of: a first cylindrical exhaust device having an inlet opening at a first longitudinal end thereof and an outlet opening at a second longitudinal end thereof and a horizontal longitudinal centerline running therethrough; a first exhaust pipe having an inlet opening and an outlet opening, the inlet opening communicating with the engine and the outlet opening communicating with the first cylindrical exhaust device; a second cylindrical exhaust device having an inlet opening at a first longitudinal end thereof and an outlet opening at a second longitudinal end thereof, the second cylindrical exhaust device having a horizontal longitudinal centerline running therethrough and being provided in a substantially parallel relationship with the centerline of the first exhaust device, and the first cylindrical exhaust device is located alongside of the second exhaust device such that the longitudinal centerlines of the first and second exhaust devices are located in substantially adjacent horizontal planes; a second exhaust pipe communicating the outlet opening of the first exhaust device with the inlet opening of the second exhaust device; and a bracket means for securing the first exhaust pipe to the second exhaust device, the bracket means being made of at least one sheet of metal, the at least one sheet of metal being secured to an extending perpendicularly between an outer peripheral flange of the first exhaust pipe and an outer peripheral portion of the second exhaust device, the at least one sheet of metal having a substantially flat surface which is substantially perpendicular to the horizontal longitudinal centerlines of the first and the second exhaust devices.
Teshima, H.
Design and Performance of a Gas Chromatograph for Automatic Monitoring of Pollutants in Ambient Air
In recent years, interest in air pollution constituents has focused on carbon monoxide and hydrocarbons as prime components of polluted air. Instrumental methods have been developed, and commercial instruments for continuous monitoring of these components have been available for a number of years. For the measurement of carbon monoxide, non-dispersive infrared spectroscopy has been the accepted tool, in spite of its marginal sensitivity at low parts-per-million levels. For continuously monitoring total hydrocarbons, the hydrogen flame ionization analyzer has been widely accepted as the preferred method. The inadequacy of this latter method became evident when it was concluded that methane is non-reactive and cannot be considered a contaminant even though present at over 1 ppm in the earth's atmosphere. Hence, the need for measuring methane separately became apparent as a means of measuring the reactive and potentially harmful non-methane hydrocarbons fraction. A gas chromatographic method for the measurement of methane and total hydrocarbons which met these requirements has been developed. In this technique, methane was separated on conventional gas chromatographic columns and detected by a hydrogen flame ionization detector (FID) while the total hydrocarbons were obtained by introducing a second sample directly into the FID without separating the various components. The reactive, or non-methane hydrocarbons, were determined by difference. Carbon monoxide was also measured after converting to methane over a heated catalyst to render it detectable by the FID. The development of this method made it possible to perform these measurements with a sensitivity of as much as 1 ppm full scale and a minimum detectability of 20 ppb. Incorporating this technique, criteria were developed by APCO for a second generation continuous automatic instrument for atmospheric monitoring stations.
Villalobos, R.; Stevens, D.; LeBlanc, R.; Braun, L.
An investigation of the effects of smoke suppressant fuel additives on engine and test cell exhaust gas opacities. Final report for 1981
Tests were conducted in a one-eighth scale turbojet test cell with a ramjet type combustor to investigate the effects of fuel additives on smoke reduction. Particle size and mass concentrations were determined at the engine and stack exhausts using three wavelength optical detector systems. Particulate samples were also collected at the engine exhaust and analyzed with a scanning electron microscope. Combustor temperature and fuel additives were found to significantly affect particulate mass concentrations emitted from the engine while particle size appeared to be unaffected. No significant changes in the particulate size or mass occurred from the engine exhaust to the stack exhaust. The optical determination of exhaust mean particulate size/mass concentration with three wavelength optical detector systems appears to be reasonably accurate technique for evaluating the effects of engine and test cell operating conditions and fuel composition changes on the emitted particulates.
Thornburg, D.W.; Darnell, T.R.; Netzer, D.W.
Seasonal characteristics of gas-phase air pollutants: implications for public health in northeastern New Jersey
To characterize the impact of urban air pollution and local weather conditions on human health, the ambient air concentrations of nitrogen oxide (NOx) and ground-level ozone (O3) were measured at the Meadowlands in Lyndhurst, NJ (41N, 74W) from June 1, 2007 to May 31, 2008. Meteorological data, mainly temperature, wind speed, relative humidity and barometric pressure, were supplemented with data from Weather Underground. Public health data were obtained from the New Jersey Department of Health and Senior Services (NJDHSS). The relationship between gas-phase pollutants and hospital admissions were examined through path analytic models by using multiple regressions and bivariate correlations. The meteorological conditions and air pollutants that may be associated with human respiratory health effects are analyzed. Preliminary results demonstrate that the ambient levels of NOx and O3 are influenced by certain meteorological conditions in the Meadowlands, and that there is a strong relationship between hospital admission and personal exposure to NO2 over the short-term. There is no direct relationship between O3 and hospital admission (r=-0.092), whereas hospital admission and NOx correlate (r=0.317) but more significantly with NO2 (r=.359) at a significance level of 0.01. Hospital admission rates are indirectly affected by humidity (r=-0.077). The seasonal dependence of pollutants is caused mainly by low wind speed and differences in chemical processing, making them interdependent. The monthly average O3 ranged from 11.1ppb to 36.2ppb with the highest values in summer; NOx ranged from 17.0ppb to 29.0ppb with no marked seasonal variations and were lower on weekends than on week days. There were dissimilar diurnal patterns and an inverse relationship between the hourly average of NOx and O3 concentrations, suggesting that O3 formation was not limited by the availability of NOx but is likely influenced by a VOC-sensitive chemical regime. This study provides a basis for the need of developing additional plans for protection against respiratory illnesses and for setting improved air quality standards in this region.
Roberts-Semple, D. A.; Gao, Y.
40 CFR 1065.230 - Raw exhaust flow meter.
...230 Raw exhaust flow meter. (a) Application...use a raw exhaust flow meter signal that does not...continuously sampled gas concentrations, if...a raw-exhaust flow meter that meets the specifications...may involve using an ultrasonic flow meter, a...
Biofiltration of the Critical Minimum Ventilation Exhaust Air
This research project investigated the gas and odor emission reduction potential from a deep-pit swine finisher using a strategy of partial biofiltration of a critical minimum amount of exhausted air (CMEA). The CMEA was defined as the amount of air exhausted to a stable hot-weather atmosphere, typical of summer night conditions. Ventilation air exhausted during the heat of summer days
S. J. Hoff; J. D. Harmon
Screening of anthropogenic compounds in polluted sediments and soils by flash evaporation\\/pyrolysis gas chromatography-mass spectrometry
The use of flash evaporation and pyrolysis gas chromatography-mass spectrometry as a fast screening procedure for anthropogenic substances in environmental samples is demonstrated by the analysis of polluted soil and sediment samples. Polycyclic aromatic hydrocarbons, haloorganics, aliphatic hydrocarbons, heteroaromatics, elemental sulfur, cyanides, and pyrolysis products of synthetic polymers are among the anthropogenic substances that can be readily detected by this
J. W. de Leeuw; E. W. B. de Leer; J. S. Sinninghe. Damste; P. J. W. Schuyl
Determination of priority organic micro-pollutants in water by gas chromatography coupled to triple quadrupole mass spectrometry
A multiclass method has been developed for screening, quantification and confirmation of organic micro-pollutants in water by gas chromatography coupled to mass spectrometry with a triple quadrupole analyzer. The work has been focused on the determination of more than 50 compounds belonging to different chemical families: 19 organochlorine and organophosphorus insecticides, 6 herbicides, 7 polychlorinated biphenyls, 16 polycyclic aromatics hydrocarbons,
E. Pitarch; C. Medina; T. Portol�s; F. J. L�pez; F. Hern�ndez
[Investigation of the limit of detection of an infrared passive remote sensing and scanning imaging system for pollution gas].
NECL could be used to estimate the limit of detection of the infrared passive remote sensing system. It was an important indicator of the sensitivity of the system. The theoretical equation of the NECL according to the atmospheric infrared radiation transfer model showed that NECL related to NESR, the brightness temperature of background and pollution gas, and the absorption coefficient of pollution gas. The remote sensing of SF6 was done. The limit of detection of the system at the different brightness temperature of background and pollution gas could be calculated. False color image of NECL was given from the measured data. The results show that NECL decreases rapidly by increasing the difference in brightness temperature of the background and pollution gas, the value of NECL was down to 10(-2) order of magnitude when the brightness temperature difference was equal to 30 K. False color image of NECL contributes to the discrimination of the limit of detection of the system in the complex background. PMID:24409702
Jiao, Yang; Xu, Liang; Gao, Min-Guang; Jin, Ling; Tong, Jing-Jing; Li, Sheng; Wei, Xiu-Li
Activated carbon load equalization of transient concentrations of gas-phase toluene: Effect of gas flow rate during pollutant non-loading intervals
Dynamically varying contaminant concentrations pose a challenge in the design and operation of biofilters for air pollution control. One strategy for managing this problem involves installation of a column packed with granular activated carbon (GAC) to achieve load equalization prior to biofilter treatment. Research described here was conducted to evaluate the effect of changes in gas flow rates during contaminant
Marilou M. Nabatilan; Ameziane Harhad; Peter R. Wolenski; William M. Moe
Argon/UF6 plasma exhaust gas reconstitution experiments using preheated fluorine and on-line diagnostics. [fissioning uranium plasma core reactor design
The feasibility of employing a flowing, high-temperature, pure fluorine/UF6 regeneration system to efficiently convert a large fraction of the effluent plasma exhaust back to pure UF6 was demonstrated. The custom built T.O.F. mass spectrometer sampling system permitted on-line measurements of the UF6 concentration at different locations in the exhaust system. Negligible amounts ( 100 ppm) of UF6 were detected in the axial bypass exhaust duct and the exhaust ducts downstream of the cryogenic trap system used to collect the UF6, thus verifying the overall system efficiency over a range of operating conditions. Use of a porous Monel duct as part of the exhaust duct system, including provision for injection of pure fluorine, provided a viable technique to eliminate uranium compound residue on the inside surface of the exhaust ducts. Typical uranium compound mass deposition per unit area of duct was 2 micron g/sq cm. This porous duct technique is directly applicable to future uranium compound transfer exhaust systems. Throughout these experiments, additional basic data on the corrosion aspects of hot, pressurized UF6/fluorine were also accumulated.
Roman, W. C.
Water pollution risk associated with natural gas extraction from the Marcellus Shale.
In recent years, shale gas formations have become economically viable through the use of horizontal drilling and hydraulic fracturing. These techniques carry potential environmental risk due to their high water use and substantial risk for water pollution. Using probability bounds analysis, we assessed the likelihood of water contamination from natural gas extraction in the Marcellus Shale. Probability bounds analysis is well suited when data are sparse and parameters highly uncertain. The study model identified five pathways of water contamination: transportation spills, well casing leaks, leaks through fractured rock, drilling site discharge, and wastewater disposal. Probability boxes were generated for each pathway. The potential contamination risk and epistemic uncertainty associated with hydraulic fracturing wastewater disposal was several orders of magnitude larger than the other pathways. Even in a best-case scenario, it was very likely that an individual well would release at least 200 m� of contaminated fluids. Because the total number of wells in the Marcellus Shale region could range into the tens of thousands, this substantial potential risk suggested that additional steps be taken to reduce the potential for contaminated fluid leaks. To reduce the considerable epistemic uncertainty, more data should be collected on the ability of industrial and municipal wastewater treatment facilities to remove contaminants from used hydraulic fracturing fluid. PMID:22211399
Rozell, Daniel J; Reaven, Sheldon J
Continuous-wave terahertz by photomixing: applications to gas phase pollutant detection and quantification
Recent advances in the development of monochromatic continuous-wave terahertz sources suitable for high resolution gas phase spectroscopy and pollution monitoring are reviewed. Details of a source using an ultra fast opto-electronic photomixing element are presented. The construction of a terahertz spectrometer using this source has allowed spectroscopic characterisation and application studies to be completed. Analysis of H 2S and OCS under laboratory conditions are used to demonstrate the spectrometer performance, and the determination of the transition line strengths and pressure self broadening coefficients for pure rotational transitions of OCS. The spectral purity 5 MHz, tunability 0.3 to 3 THz, and long wavelength ?200 ?m of this source have been exploited to identify and quantify numerous chemical species in cigarette smoke. The key advantages of this frequency domain are its high species selectivity and the possibility to make reliable measurements of gas phase samples heavily contaminated by aerosols and particles. To cite this article: F. Hindle et al., C. R. Physique 9 (2008).
Hindle, Francis; Cuisset, Arnaud; Bocquet, Robin; Mouret, Ga�l
The goal of this exploratory research project is to control the pollutant emissions of diffusion flames by modifying the air infusion rate into the flame. The modification was achieved by installing a cascade of venturis around the burning gas jet. The basic idea behind this technique is controlling the stoichiometry of the flame through changing the flow dynamics and rates of mixing in the combustion zone with a set of venturis surrounding the flame. A natural gas jet diffusion flame at burner-exit Reynolds number of 5100 was examined with a set of venturis of specific sizes and spacing arrangement. The thermal and composition fields of the baseline and venturi-cascaded flames were numerically simulated using CFD-ACE+, an advanced computational environment software package. The instantaneous chemistry model was used as the reaction model. The concentration of NO was determined through CFD-POST, a post processing utility program for CFD-ACE+. The numerical results showed that, in the near-burner, midflame and far-burner regions, the venturi-cascaded flame had lower temperature by an average of 13%, 19% and 17%, respectively, and lower CO{sub 2} concentration by 35%, 37% and 32%, respectively, than the baseline flame. An opposite trend was noticed for O{sub 2} concentration; the cascaded flame has higher O{sub 2} concentration by 7%, 26% and 44%, in average values, in the near-burner, mid-flame and far-burner regions, respectively, than in the baseline case. The results also showed that, in the near-burner, mid-flame, and far-burner regions, the venturi-cascaded flame has lower NO concentrations by 89%, 70% and 70%, in average values, respectively, compared to the baseline case. The numerical results substantiate that venturi-cascading is a feasible method for controlling the pollutant emissions of a burning gas jet. In addition, the numerical results were useful to understand the thermo-chemical processes involved. The results showed that the prompt-NO mechanism plays an important role besides the conventional thermal-NO mechanism. The computational results of the present study need to be validated experimentally.
Dr. Ala Qubbaj
Removal of NO x from a Lean Exhaust Gas by Absorption on Heteropolyacids: Reversible Sorption of Nitrogen Oxides in H 3PW 12O 40�6H 2O
NOx adsorption\\/desorption capacities of 12-tungstophosphoric acid hexahydrate (HPW) were measured under representative exhaust lean gas mixture conditions. The amounts of NOx adsorbed were large and equal to 38 mg\\/g of HPW. On such material desorption is observed during the cooling phase under wet air conditions. This type of behaviour is very unusual and has never been reported previously. NO and
S Hodjati; C Petit; V Pitchon; A Kiennemann
A new concept for the removal of NO x from a lean exhaust gas using storage on H 3PW 12O 40�6H 2O, a very fast desorption and a reduction over a TWC
NOx storage and reduction capacities of H3PW12O40�6H2O were measured under representative exhaust lean gas mixture conditions. The efficiency of sorption was approximately 50%. Upon switching to a short, rich excursion, a small portion of NOx was released as NO, though a fraction of the pre-absorbed NOx were reduced. This process proved to be slow. However the addition of 1% Pt
K. Vaezzadeh; C. Petit; V. Pitchon; A. Kiennemann
The Effect of Sulphur on the Activity of Pd\\/Al 2 O 3 , Pd\\/CeO 2 and Pd\\/ZrO 2 Diesel Exhaust Gas Catalysts
Pd\\/Al2O3, Pd\\/CeO2 and Pd\\/ZrO2 diesel oxidation catalysts and their washcoat materials were studied after sulphur treatment. The catalytic activities were\\u000a analysed in simplified diesel exhaust gas composition by FT-IR technique. ICP-OES or XRF, physisorption and CO chemisorption\\u000a was used to catalyst characterisation. The result shows that the sulphur treatment clearly deactivates the studied catalysts.
T. Kolli; M. Huuhtanen; A. Hallikainen; K. Kallinen; R. L. Keiski
An experimental study of jet exhaust simulation
Afterbody drag predictions for jet aircraft are usually made experimentally with the jet exhaust flow simulated. The physical gas properties of the fluid used for the model jet exhaust can affect the accuracy of simulation of the airplane's jet exhaust plume. The effect of the accuracy of this simulation on afterbody drag was investigated by wind-tunnel tests with single engine model. In addition to unheated air as the exhaust gas, the decomposition products of three different concentrations of hydrogen peroxide were utilized. The air jet simulation consistently resulted in higher boattail drag than hydrogen peroxide simulation. The differences in drag for the various exhaust gases are attributed to different plume shapes and entrainment properties of the gases. The largest differences in drag due to exhaust gas properties were obtained for the combination of high transonic Mach numbers and high boattail angles. For these conditions, the current data indicate that the use of air to simulate a nonafterburning turbojet exhaust can result in an increase in afterbody amounting to 20 percent of the nonafterburning turbojet value.
Compton, W. B., III
A model gas study of ammonium formate, methanamide and guanidinium formate as alternative ammonia precursor compounds for the selective catalytic reduction of nitrogen oxides in diesel exhaust gas
Ammonium formate, methanamide and guanidinium salts were investigated in model gas experiments and found to be suitable ammonia precursor compounds for the selective catalytic reduction (SCR) of nitrogen oxides since they decompose to ammonia over different metal oxide catalysts.The decomposition of ammonium formate started with thermolysis to formic acid and ammonia. Formic acid reacted further, mainly to water and CO
Oliver Kr�cher; Martin Elsener; Eberhard Jacob
Advances in the gas chromatographic determination of persistent organic pollutants in the aquatic environment.
Environmental chemists have been challenged for over 30 years to analyse complex mixtures of halogenated organic pollutants like polychlorinated biphenyls (PCBs), polychlorinated alkanes (PCAs), polybrominated diphenyl ethers (PBDEs) and polychlorinated dibenzo-p-dioxins and polychlorinated furans (PCDD/Fs). Gas chromatography (GC) often proved to be the method of choice because of its high resolution. The recent developments in the field of comprehensive two-dimensional GC (GCxGC) show that this technique can provide much more information than conventional (single-column) GC. Large volume injection (e.g. by programmed temperature vaporiser, or on-column injection) can be employed for the injection of tens of microliters of sample extract, in that way substantially improving the detection limits. Electron-capture detection (ECD) is a sensitive detection method but unambiguous identification is not possible and misidentification easily occurs. Mass spectrometric (MS) detection substantially improves the identification and the better the resolution (as with MS/MS, time-of-flight (TOF) MS and high-resolution (HR)MS), the lower the chances of misidentification are. Unfortunately, this comes only with substantially higher investments and maintenance costs. Co-extracted lipids, sulphur and other interferences can disturb the GC separation and detection leading to unreliable results. Extraction, and more so, sample clean-up and fractionation, are crucial steps prior to the GC analysis of these pollutants. Recent developments in sample extraction and clean-up show that selective pressurised liquid extraction (PLE) is an effective and efficient extraction and clean-up technique that enables processing of multiple samples in less than 1h. Quality assurance tools such as interlaboratory studies and reference materials are very well established for PCDD/Fs and PCBs but the improvement of that infrastructure is needed for brominated flame retardants, PCAs and toxaphene. PMID:18291406
van Leeuwen, S P J; de Boer, J
CFD Simulation of Gas Pollutant Motion and Dispersion Problem in Wind Tunnel with Respect to Froude Number
Low speed wind tunnels have been used for simulation of wide range of physical problems. One of many possible applications is a simulation of gas pollutant motion and dispersion considering different density of each one. Source term can be defined as a point source, line source or volume source. If modeled geometry with the source is downscaled geometrically and pollutant release is limited (considering all other atmospheric conditions consistent), the plume of pollutant can change its way of motion and dispersion (comparing with the reality). These changes include not only a shape of the plume but also an ability of plume to climb or descent in the atmosphere. Especially plume vertical motions are of the highest importance for the plume motion and dispersion in the real atmosphere. The main point of this article is to prove that downscaled physical experiments based on gas pollutant's motion and dispersion could not be always the best approach for making gas dispersion studies in the field of emergency planning (especially when criteria of hydrodynamic physical similarity are not respected enough). CFD code ANSYS Fluent 12.1.4 was used as a tool for numerical simulation and visualization of the problem.
Zavila, Ondrej
40 CFR 86.1310-2007 - Exhaust gas sampling and analytical system for gaseous emissions from heavy-duty diesel-fueled...
...substituted for the exhaust measurement of CO2 . General...heat exchanger or electronic flow compensation...Alternative NOX measurement techniques outlined in § 86...permitted for NOX measurement in this subpart;...
Disruption of the respiratory epithelium contributes to the progression of a variety of respiratory diseases that are aggravated by exposure to air pollutants, specifically traffic-based pollutants such as diesel exhaust particles (DEP). Recognizing that lung repair following inj...
Exhaust Gas Turbocharged Submarine Engines.
Supercharged submarine propulsion systems have the following technical and economic advantages: Higher power density, lower fuel consumption, maximum identity with standard propulsion systems. The design and successful tests of a new supercharger (simple ...
V. M. W. Jost
Automobile exhaust level of CO: study in Chidambaram town.
The exhaust gases from automobiles constitute about 75% of air pollution. Among the various pollutants emitted from vehicles, CO is the primary pollutant and very toxic one. The CO monitor method was used to predict the CO level in Chidambaram town. From the study it is evident that the pollution level is closely related to the density of motor vehicles on the roads. With increase in number of motor vehicles pollution level also increases which pollutes the roadside environment severely in future. PMID:12968723
Ramamurthy, N; Thirumarran, M
Modeling Population Exposures to Pollutants Emitted from Natural Gas Cooking Burners
We developed a physics-based data-supported model to investigate indoor pollutant exposure distributions resulting from use of natural gas cooking appliances across households in California. The model was applied to calculate time-resolved indoor concentrations of CO, NO2 and formaldehyde resulting from cooking burners and entry with outdoor air. Exposure metrics include 1-week average concentrations and frequency of exceeding ambient air quality standards. We present model results for Southern California (SoCal) using two air-exchange scenarios in winter: (1) infiltration-only, and (2) air exchange rate (AER) sampled from lognormal distributions derived from measurements. In roughly 40percent of homes in the SoCal cohort (N=6634) the 1-hour USEPA NO2 standard (190 ?g/m3) was exceeded at least once. The frequency of exceeding this standard was largely independent of AER assumption, and related primarily to building volume, emission rate and amount of burner use. As expected, AER had a more substantial impact on one-week average concentrations.
Lobscheid, Agnes; Singer, Brett C.; Klepeis, Neil E.
Combined air and water pollution control system
A bioaquatic air pollution control system for controlling both water and atmospheric pollution is disclosed. The pollution control system includes an exhaust for directing polluted gases out of a furnace and a fluid circulating system which circulates fluid, such as waste water, from a source, past the furnace where the fluid flow entrains the pollutants from the furnace. The combined fluid and pollutants are then directed through a rock/plant/microbial filtering system. A suction pump pumps the treated waste water from the filter system past the exhaust to again entrain more pollutants from the furnace where they are combined with the fluid (waste water) and directed to the filter system.
Wolverton, Billy C. (inventor); Jarrell, Lamont (inventor)
Source apportionment of wintertime gas-phase and particle-phase air pollutants using organic compounds as tracers
Two chemical mass balance receptor models are developed which can determine the source contributions to atmospheric pollutant concentrations using organic compounds as tracers. The first model uses particle-phase organic compounds to apportion the primary source contribution to atmospheric fine particulate organic carbon concentrations and fine particle mass concentrations. The second receptor model simultaneously uses both volatile gas-phase hydrocarbon and particle-phase
James J. Schauer; Glen R. Cass
Mercaptans emissions in diesel and biodiesel exhaust
Biodiesel and ethanol are fuels in clear growth and evidence, basically due to its relation with the greenhouse effect reduction. There are several works regarding regulated pollutants emissions, but there is a lack of reports in non-regulated emissions. In a previous paper (Corr�a and Arbilla, 2006) the emissions of aromatic hydrocarbons were reported and in 2007 another paper was published in 2008 focusing carbonyls emissions (Corr�a and Arbilla, 2008). In this work four mercaptans (methyl, ethyl, n-propyl and n-butyl mercaptans) were evaluated for a heavy-duty diesel engine, fueled with pure diesel (D) and biodiesel blends (v/v) of 2% (B2), 5% (B5), 10% (B10), and 20% (B20). The tests were carried using a six cylinder heavy-duty engine, typical of the Brazilian fleet of urban buses, during a real use across the city. The exhaust gases were diluted near 20 times and the mercaptans were sampled with glass fiber filters impregnated with mercuric acetate. The chemical analyses were performed by gas chromatography with mass spectrometry detection. The results indicated that the mercaptans emissions exhibit a reduction with the increase of biodiesel content, but this reduction is lower as the mercaptan molar mass increases. For B20 results the emission reduction was 18.4% for methyl mercaptan, 18.1% for ethyl mercaptan, 16.3% for n-propyl mercaptan, and 9.6% for n-butyl mercaptan.
Corr�a, S�rgio Machado; Arbilla, Graciela
Exposure to Diesel Exhaust Enhances the Generation of Vascular Microparticles
Introduction: In the study of the health impacts of traffic-related air pollution, diesel exhaust is a pollutant of particular interest, since it is a major source of particulate matter (PM). Epidemiological studies associate exposure to ambient levels of PM with cardiovascular m...
Remote sensing of aircraft exhaust temperature and composition by passive Fourier Transform Infrared (FTIR)
The scanning infrared gas imaging system (SIGIS-HR) and the quantitative gas analysis software MAPS (Multicomponent Air Pollution Software) are applied to investigate the spatial distribution of the temperature and gas concentrations (CO, NO) within the plume of aircraft engines at airports. The system integrates an infrared camera also. It is used for the localisation of the hot source that additionally suggests the best measurement position of the SIGIS-HR. The application of emission FTIR spectrometry for the measurement of temperature and gas emission index of CO and NO is presented for the exhaust of a small turbojet based on a helicopter turbine. In these measurements the emitted infrared radiation from the exhaust gas stream was collected by the SIGIS-HR at different spectral resolution (56 cm -1 and 0.2 cm -1). The software MAPS includes the Instrumental Line Shape (ILS) of the OPAG- 22 FTIR spectrometer obtained by active gas cell measurements and ILS modelling. The rough concept of the system will be presented and operational applications will be discussed. The results of the investigation of the temperature and gas concentrations (CO, NO) within the aircraft engine plumes will be shown. The limitations and of the systems will be discussed.
Flores, Edgar; Sch�fer, Klaus; Black, John; Harig, Roland; Jahn, Carsten
Non-catalytic reduction of NO in diesel exhaust with the addition of methylamine
The present study investigated a chemical gas-phase process capable of reducing nitric oxides in diesel engine exhaust. In this process, monomethylamine (CH3NH2) was added to the exhaust gas and the chemical reactions of NO decomposition took place in the exhaust gas. In the present experiment, the effect of coexisting constituents in the diesel exhaust on NO decomposition was examined. Results
Yasufumi Nakanishi; Yoshinobu Yoshihara; Kazuie Nishiwaki
The effect of heat transfer on performance of the Diesel cycle and exergy of the exhaust gas stream in a LHR Diesel engine at the optimum injection timing
In this study, a Diesel cycle analysis taking combustion and heat transfer into account on performance has been performed. The effect of heat transfer is analysed in terms of design parameters such as compression ratio and cut-off ratio. The effects of heat transfer from the cylinder on exhaust temperature were also investigated for different heat transfer and combustion modes. It
Adnan Parlak
Duplex tab exhaust nozzle
An exhaust nozzle includes a conical duct terminating in an annular outlet. A row of vortex generating duplex tabs are mounted in the outlet. The tabs have compound radial and circumferential aft inclination inside the outlet for generating streamwise vortices for attenuating exhaust noise while reducing performance loss.
Gutmark, Ephraim Jeff (Inventor); Martens, Steven (nmn) (Inventor)
Insulated exhaust cover
This patent describes a device for insulating one or more pipes in the exhaust system of an internal combustion engine. It comprises: a layer of insulating material circumscribingly engaging the outer surface of the exhaust pipe, a flexible metal sleeve defining an elongated passageway having a diameter, a means for retaining the insulating material and the metal sleeve in stationary
Diesel engine exhaust oxidizer
This patent describes a diesel engine exhaust oxidizing device. It comprises: an enclosure having an inlet for receiving diesel engine exhaust, a main flow path through the enclosure to an outlet of the enclosure, a by-ass through the enclosure, and a microprocessor control means.
Kammel, R.A.
The Environmental Protection Agency (EPA), Office of Research and Development has undertaken an extensive study to determine synthetic fuel plant waste stream characteristics and to evaluate potentially applicable pollution control systems. The purpose of this and all other PCTMs...
Combating urban air pollution through Natural Gas Vehicle (NGV) analysis, testing, and demonstration.
Deteriorating urban air quality ranks as a top concern worldwide, since air pollution adversely affects both public health and the environment. The outlook for improving air quality in the world's megacities need not be bleak, however, The use of natural ...
The emissions programs in the Atmospheric Protection Branch (APB) of NRMRL's Air Pollution Prevention and Control Division are primarily dedicated to anthropogenic (human-influenced) sources of methane and high-global-warming refrigerants, though some work addresses carbon dioxid...
Surface nanocrystallization of Al-plated steel for application in the exhaust system of vehicles
Aluminum-plated or aluminized steel has been used in the exhaust system of vehicles, which exhibits a reasonably high corrosion resistance in the exhaust gas condensate environment. However, due to the inhomogeneous element distribution the outmost surface layer, which is directly exposed to the exhaust gas, is more like an aluminum layer (with little intermetallic compounds) that, though corrosion-resistant, may not
C. Chen; C. J. Shang; D. Y. Li
Space shuttle exhaust cloud properties
A data base describing the properties of the exhaust cloud produced by the launch of the Space Transportation System and the acidic fallout observed after each of the first four launches was assembled from a series of ground and aircraft based measurements made during the launches of STS 2, 3, and 4. Additional data were obtained from ground-based measurements during firings of the 6.4 percent model of the Solid Rocket Booster at the Marshall Center. Analysis indicates that the acidic fallout is produced by atomization of the deluge water spray by the rocket exhaust on the pad followed by rapid scavening of hydrogen chloride gas aluminum oxide particles from the Solid Rocket Boosters. The atomized spray is carried aloft by updrafts created by the hot exhaust and deposited down wind. Aircraft measurements in the STS-3 ground cloud showed an insignificant number of ice nuclei. Although no measurements were made in the column cloud, the possibility of inadvertent weather modification caused by the interaction of ice nuclei with natural clouds appears remote.
Anderson, B. J.; Keller, V. W.
Effect of ethanol-gasoline blends on small engine generator energy efficiency and exhaust emission.
This study was focused on fuel energy efficiency and pollution analysis of different ratios of ethanol-gasoline blended fuels (E0, E3, E6, and E9) under different loadings. In this research, the experimental system consisted of a small engine generator, a particulate matter measurement system, and an exhaust gas analyzer system. Different fuels, unleaded gasoline, and ethanol-gasoline blends (E0, E3, E6, and E9) were used to study their effects on the exhaust gas emission and were expressed as thermal efficiency of the small engine generator energy efficiency. The results suggested that particle number concentration increased as the engine loading increased; however, it decreased as the ethanol content in the blend increased. While using E6 as fuel, the carbon monoxide (CO) concentration was less than other fuels (E0, E3, and E9) for each engine loading. The average of CO concentration reduction by using E3, E6, and E9 is 42, 86, and 83%, respectively. Using an ethanol-gasoline blend led to a significant reduction in exhaust emissions by approximately 78.7, 97.5, and 89.46% of the mean average values of hydrocarbons (HCs) with E3, E6, and E9 fuels, respectively, for all engine loadings. Using an ethanol-gasoline blend led to a significant reduction in exhaust emissions by approximately 35, 86, and 77% of the mean average values of nitrogen oxides (NOx) with E3, E6, and E9 fuels, respectively, at each engine loading. The E6 fuel gave the best results of the exhaust emissions, and the E9 fuel gave the best results of the particle emissions and engine performance. The thermal efficiency of the small engine generator increased as the ethanol content in the blend increased and as the engine loading increased. PMID:20222526
Lin, Wen-Yinn; Chang, Yuan-Yi; Hsieh, You-Ru
Performance assessment of U.S. residential cooking exhaust hoods.
This study assessed the performance of seven new residential cooking exhaust hoods representing common U.S. designs. Laboratory tests were conducted to determine fan curves relating airflow to duct static pressure, sound levels, and exhaust gas capture efficiency for front and back cooktop burners and the oven. Airflow rate sensitivity to duct flow resistance was higher for axial fan devices than for centrifugal fan devices. Pollutant capture efficiency (CE) ranged from <15% to >98%, varying across hoods and with airflow and burner position for each hood. CE was higher for back burners relative to front burners, presumably because most hoods covered only part of the front burners. Open hoods had higher CE than those with grease screen and metal-covered bottoms. The device with the highest CE--exceeding 80% for oven and front burners--had a large, open hood that covered most of the front burners. The airflow rate for this hood surpassed the industry-recommended level of 118 L�s(-1) (250 cfm) and produced sound levels too high for normal conversation. For hoods meeting the sound and fan efficacy criteria for Energy Star, CE was <30% for front and oven burners. PMID:22568807
Delp, William W; Singer, Brett C
Pollution Gradients and Chemical Characterization of Particulate Matter from Vehicular Traffic Near Major Roadways: Results from the 2009 Queens College Air Quality Study in NYC
We present measurements of traffic-related pollutants made near the Long Island Expressway (LIE, I-495), in Queens, New York. The Aerodyne Research Inc. (ARI) mobile laboratory (AML) was deployed to map spatial and temporal gradients of gas-phase species and particulate matter (PM) associated with vehicular exhaust in the residential areas near the LIE. We observe that pollutant levels build up during
Paola Massoli; Edward C. Fortner; Manjula R. Canagaratna; Leah R. Williams; Qi Zhang; Yele Sun; James J. Schwab; Achim Trimborn; Timothy B. Onasch; Kenneth L. Demerjian; Charles E. Kolb; Douglas R. Worsnop; John T. Jayne
The challenges of reducing greenhouse gas emissions and air pollution through energy sources: evidence from a panel of developed countries.
The objective of the study is to investigate the long-run relationship between climatic factors (i.e., greenhouse gas emissions, agricultural methane emissions, and industrial nitrous oxide emission), air pollution (i.e., carbon dioxide emissions), and energy sources (i.e., nuclear energy; oil, gas, and coal energy; and fossil fuel energy) in the panel of 35 developed countries (including EU-15, new EU member states, G-7, and other countries) over a period of 1975-2012. In order to achieve this objective, the present study uses sophisticated panel econometric techniques including panel cointegration, panel fully modified OLS (FMOLS), and dynamic OLS (DOLS). The results show that there is a long-run relationship between the variables. Nuclear energy reduces greenhouse gases and carbon emissions; however, the other emissions, i.e., agricultural methane emissions and industrial nitrous oxide, are still to increase during the study period. Electricity production from oil, gas, and coal sources increases the greenhouse gases and carbon emissions; however, the intensity to increase emissions is far less than the intensity to increase emissions through fossil fuel. Policies that reduce emissions of greenhouse gases can simultaneously alter emissions of conventional pollutants that have deleterious effects on human health and the environment. PMID:24584642
Akhmat, Ghulam; Zaman, Khalid; Shukui, Tan; Sajjad, Faiza; Khan, Muhammad Azhar; Khan, Muhammad Zahir
Diesel Exhaust Inhalation Increases Cardiac Output, Bradyarrhythmias, and Parasympathetic Tone in Aged Heart Failure-Prone Rats
Acute air pollutant inhalation is linked to adverse cardiac events and death, and hospitalizations for heart failure. Diesel exhaust (DE) is a major air pollutant suspected to exacerbate preexisting cardiac conditions, in part, through autonomic and electrophysiologic disturbance...
Examination of cytokines and metals in exhaled breath condensate and lung lavage fluids after diesel exhaust exposure
Epidemiology studies link human exposure to ambient air pollution with the development and exacerbation of cardiopulmonary disease. Diesel exhaust (DE) is a significant source of ambient air pollution, and thus may contribute to adverse pulmonary health effects. Previous human re...
14 CFR 34.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.
...and analytical procedures for measuring smoke exhaust emissions. 34.82 Section...AIRPLANES Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines...and analytical procedures for measuring smoke exhaust emissions. The system and...
40 CFR 87.82 - Sampling and analytical procedures for measuring smoke exhaust emissions.
...and analytical procedures for measuring smoke exhaust emissions. 87.82 Section...AIRCRAFT ENGINES Test Procedures for Engine Smoke Emissions (Aircraft Gas Turbine Engines...and analytical procedures for measuring smoke exhaust emissions. The system and...
40 CFR 90.414 - Raw gaseous exhaust sampling and analytical system description.
...that attaches the probe to the exhaust pipe must be as small as practical in order to minimize heat loss from the probe. (2...transport system from the engine exhaust pipe to the HC analyzer for the raw gas...
Atmospheric scavenging exhaust
Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. The airborne HCl concentration varied from 0.2 to 10.0 ppm and the raindrop sizes tested included 0.55 mm, 1.1 mm, and 3.0 mm. Two chambers were used to conduct the experiments. A large, rigid walled, spherical chamber stored the exhaust constituents while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique employed. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity.
Fenton, D. L.; Purcell, R. Y.
Experimental Evaluation of Installed Cooking Exhaust Fan Performance
The installed performance of cooking exhaust fans was evaluated through residential field experiments conducted on a sample of 15 devices varying in design and other characteristics. The sample included two rear downdraft systems, two under-cabinet microwave over range (MOR) units, three different installations of an under-cabinet model with grease screens across the bottom and no capture hood, two devices with grease screens covering the bottom of a large capture hood (one under-cabinet, one wall-mount chimney), four under-cabinet open hoods, and two open hoods with chimney mounts over islands. Performance assessment included measurement of airflow and sound levels across fan settings and experiments to quantify the contemporaneous capture efficiency for the exhaust generated by natural gas cooking burners.Capture efficiency is defined as the fraction of generated pollutants that are removed through the exhaust and thus not available for inhalation of household occupants. Capture efficiency (CE) was assessed for various configurations of burner use (e.g., single front, single back, combination of one front and one back, oven) and fan speed setting. Measured airflow rates were substantially lower than the levels noted in product literature for many of the units. This shortfall was observed for several units costing in excess of $1000. Capture efficiency varied widely (from<5percent to roughly 100percent) across devices and across conditions for some devices. As expected, higher capture efficiencies were achieved with higher fan settings and the associated higher air flow rates. In most cases, capture efficiencies were substantially higher for rear burners than for front burners. The best and most consistent performance was observed for open hoods that covered all cooktop burners and operated at higher airflow rates. The lowest capture efficiencies were measured when a front burner was used with a rear backdraft system or with lowest fan setting for above the range systems that do not cover the front burners.
Singer, Brett C.; Delp, William W.; Apte, Michael G.
Trade-off in emissions of acid gas pollutants and of carbon dioxide in fossil fuel power plants with carbon capture
This paper investigates the impact of capture of carbon dioxide (CO2) from fossil fuel power plants on the emissions of nitrogen oxides (NOX) and sulphur oxides (SOX), which are acid gas pollutants. This was done by estimating the emissions of these chemical compounds from natural gas combined cycle and pulverized coal plants, equipped with post-combustion carbon capture technology for the
Evangelos Tzimas; Arnaud Mercier; Calin-Cristian Cormos; Stathis D. Peteves
Developing, Coupling, and Applying a Gas, Aerosol, Transport, and Radiation Model to Study Urban and Regional Air Pollution.
This thesis discusses the development of a gas, aerosol, transport, and radiation air quality model (GATOR), the coupling of GATOR to a mesoscale meteorological and tracer dispersion model (MMTD), and the application of the resulting GATOR/MMTD air pollution modeling system (APMS) to studies of gas and aerosol pollution buildup in the Los Angeles Basin. GATOR consists of computer algorithms that simulate four groups of atmospheric processes: gas, aerosol, transport, and radiation processes. Gas processes include chemistry, emissions, gas-to-particle conversion, optical depth attenuation, and deposition. Aerosol processes include size-resolved emissions, nucleation, coagulation, condensational growth, dissolutional growth, evaporation, chemical equilibrium, aqueous chemistry, optical depth attenuation, deposition, and sedimentation. Transport processes include horizontal advection and diffusion and vertical diffusion of all gases and particles, and they require meteorological data as inputs. To drive the transport processes, the MMTD, developed by R. Lu and R. P. Turco, was coupled to GATOR. The MMTD predicts wind speed, wind direction, temperature, humidity, and pressure, among other variables. Finally, radiation processes in GATOR include spectrally-resolved scattering and absorption by gases, aerosols, fogs, and clouds, and calculation of mean intensities and heating rates. I used the GATOR/MMTD modeling system to predict pollution buildup in Los Angeles during the Southern California Air Quality Study (SCAQS) period of August 26-28, 1987. Among the model inputs were emissions, soil moisture, albedo, topographical, landuse, and chemical rate data. To validate the model, surface observations were compared to model predictions of gas-phase ozone, nitric oxide, nitrogen dioxide, carbon monoxide, sulfur dioxide, methane, total non-methane hydrocarbons, formaldehyde, peroxyacetylnitrate, hydrogen peroxide, nitric acid, nitrous acid, and ammonia concentrations. Observations were also compared to predictions of aerosol-phase ammonium, nitrate, sodium, chloride, sulfate, and total particulate concentrations. Finally, observations were compared to predictions of solar radiation and scattering coefficients. In sum, the GATOR/MMTD system predicted ozone to within a normalized gross error of 20 -35% during the study period. Additional statistics and time-series plots are shown.
Jacobson, Mark Zachary
Gas chromatography - mass spectrometric analysis of four polluted river waters for phenolic and organic compounds.
Forty-four water samples from eleven sampling points were collected from four highly polluted rivers of northern India once in each four seasons during 1988-1989. The samples were analyzed for phenol, chlorophenols, a few bromophenols and other organics. Phenol was found to be absent in all the analyzed samples. Trichlorophenol and pentachlorophenol were frequently detected. Comparatively, the Ganges river was most polluted at Kannauj followed by Narora, Kachala and Fatehgarh. Maximum phenols were found at Mathura downstream of the Yamuna river followed by Mathura upstream, Okhla, ITO and none at Wazirabad. No phenols were detected in the water of the rivers Hindon and Kali at Ghaziabad and Aligarh, respectively. Some other organic pollutants were also identified by their mass spectra and supported by data from the computerized library, but, not quantified. PMID:24198068
Nomani, A A; Ajmal, M; Ahmad, S
Elevated exhaust temperature, zoned, electrically-heated particulate matter filter
A system includes an electrical heater and a particulate matter (PM) filter that is arranged one of adjacent to and in contact with the electrical heater. A control module selectively increases an exhaust gas temperature of an engine to a first temperature and that initiates regeneration of the PM filter using the electrical heater while the exhaust gas temperature is above the first temperature. The first temperature is greater than a maximum exhaust gas temperature at the PM filter during non-regeneration operation and is less than an oxidation temperature of the PM.
Gonze, Eugene V [Pinckney, MI; Bhatia, Garima [Bangalore, IN
Effects of engine operating and design variables on exhaust emissions
To determine the influence of engine variables on the composition of exhaust gas, engine dynamometer tests were conducted on single and multicylinder reciprocating engines. The following engine variables were investigated: air-fuel ratio, power output, engine speed, spark timing, exhaust back pressure, valve overlap, combustion chamber deposits, and intake manifold pressure. Hydrocarbon concentrations were found to be considerably affected by changes
D. F. Hagen; G. W. Holiday
The report describes the development of a device that is capable of sampling gaseous emissions from automobiles. The device samples exhaust gases at a mass rate that is proportional to the total exhaust gas mass flow rate, which is measured using an ultrasonic vortex flowmeter. T...
A test program was initiated to characterize exhaust gas emissions from an automobile equipped with a dual catalyst system. The dual catalyst system was designed by Gould, Inc. to reduce emissions of engine exhaust hydrocarbons, carbon monoxide, and nitrogen oxides. It basically ...
Development and application of a new air pollution modeling system-part I: Gas-phase simulations
A new air pollution modeling system is discussed and applied. The system consists of GATOR, a gas, aerosol, transport, and radiation air quality model and MMTD, a mesoscale meteorological and tracer dispersion model. The gas-phase processes treated by GATOR include photochemistry, deposition, emissions, and gas-to-particle conversion. To solve stiff chemical rate equations, a sparse-matrix, vectorized Gear-type code (SMVGEAR) was used. The aerosol processes in GATOR include coagulation, aqueous chemistry, chemical equilibrium, condensational growth, dissolutional growth, evaporation, nucleation, emissions, deposition, and sedimentation. The transport processes include horizontal advection and diffusion and vertical convection and diffusion. Finally, the radiation algorithm calculates ultraviolet, visible, and infrared optical depths, mean intensities for photodissociation rates, and radiative heat fluxes for temperature calculations. The MMTD predicts winds, diffusion, temperature, pressure, humidity, soil moisture, and rainfall. These variables are fed to GATOR and radiative heating rates from GATOR are fed back to the MMTD. With the GATOR/MMTD system, gas-phase pollution was simulated for the Southern California Air Quality Study (SCAQ) days of 26-28 August 1987. Results were compared to surface measurements for many parameters. The model predicted normalized gross errors for ozone of 17.6% and 23.4% at 2:30 p.m. on the first and second days of simulation, respectively. Also, the normalized gross error during the first 12 h of simulation was 22%. Correct emissions and initial mixing ratios appear to be necessary for obtaining good results. Initial conditions outside the basin seem to affect results by the second and third days. Time-series plots, statistics, and a sensitivity test are discussed. Aerosol simulation results will be shown in a later work.
Jacobson, Mark Z.; Lu, Rong; Turco, Richard P.; Toon, Owen B.
Large-scale time-resolved digital particle image velocimetry (TR-DPIV) for measurement of high subsonic hot coaxial jet exhaust of a gas turbine engine
The development of a highly configurable triple digital particle image velocimetry (DPIV) system is described, which is capable of acquiring both continuous, statistically independent measurements at up to 14 Hz and time-resolved PIV data at MHz rates. The system was used at QinetiQ's Noise Test Facility (NTF) as part of the EU-funded CoJeN programme to obtain measurements from high subsonic (Mach <= 0.9), hot (~500 �C), large (1/10th) scale coaxial jet flows at a standoff distance of ~1 m. High-resolution time-averaged velocity and turbulence data were obtained for complete coaxial engine exhaust plumes down to 4 m (20 jet diameters) from the nozzle exit in less than 1 h. In addition, the system allowed volumetric data to be obtained, enabling fast assessment of spatial alignment of nozzle configurations. Furthermore, novel six-frame time-series data-capture is demonstrated up to 330 kHz, used to calculate time-space correlations within the exhaust, allowing for study of spatio-temporal developments in the jet, associated with jet-noise production. The highly automated system provides synchronization triggers for simultaneous acquisition from different measurement systems (e.g. LDA) and is shown to be versatile, rugged, reliable and portable, operating remotely in a hostile environment. Data are presented for three operating conditions and two nozzle geometries, providing a database to be used to validate CFD models of coaxial jet flow.
Timmerman, B. H.; Skeen, A. J.; Bryanston-Cross, P. J.; Graves, M. J.
40 CFR 86.110-94 - Exhaust gas sampling system; diesel-cycle vehicles, and Otto-cycle vehicles requiring particulate...
...necessary for petroleum-fueled, natural gas-fueled and liquefied...3) For gasoline-fueled, natural gas-fueled and liquefied...Otto-cycle and petroleum-fueled, natural gas- fueled and liquefied...selected simultaneously with the selection of an empty gaseous...
Numerical Investigation of Turbulent Diffusion in Push Pull and Exhaust Fume Cupboards
The aim of this study is to investigate airflow motions and associated pollutant distributions in fume hoods. Currently, most exhaust fume hoods are designed to use an airflow induced by a fan at the top to remove pollutants. Ambient fluids are drawn, flowing toward the opening and subsequently turning to the outlet at the roof. Pollutants are supposedly captured by
Ultrafine particles pollution in urban coastal air due to ship emissions
Two years of experimental data (2008-2009) of particle number (?2.5 nm diameter) and black carbon concentrations and of gaseous pollutants recorded in the ambient air of a coastal city were analysed in order to assess the impact of ship emissions on the ultrafine particles (UFPs, diameter <100 nm) concentrations in urban ambient air. The observed relationship between particle number and the other air pollutants, allowed segregating the contribution of vehicle exhaust and of ship emissions to the UFP concentrations in the urban ambient air. Vehicle exhausts resulted in high concentrations of UFP, black carbon and NO x during the early morning, when UFPs showed concentrations 15-30 � 10 3 cm -3. Pollutants linked to this source rapidly decreased when inland sea breeze started to flow. However, this airflow resulted in inland transport of ship plumes (emitted in the harbour and in the sea) into the city and in high concentrations of SO 2, NO x and UFP from mid morning to the evening. In this context, UFPs showed concentrations 35-50 � 10 3 cm -3, being the 65-70% of these linked to ship emissions mostly related to SO 2 (gas phase precursor). UFPs pollution is a matter of concern due to adverse effects on human health. Up to the date, most of studies on urban air quality and UFPs have focused on vehicle exhaust emissions. This study shows how inland transport of ship plumes due to sea breeze blowing results in UFPs pollution in coastal cities.
Gonz�lez, Yenny; Rodr�guez, Sergio; Guerra Garc�a, Juan Carlos; Trujillo, Juan Luis; Garc�a, Rosa
Exhaust energy recovery and generator for use with an engine
An exhaust energy recovery and generator device for a thermally insulative engine having an exhaust passage and an output shaft is described. The device comprises: (a) a first exhaust turbine disposed in the exhaust passage of the thermally insulative engine and rotatable by the energy of an exhaust gas discharged from the thermally insulative engine. The first exhaust turbine has a wheel and a wheel shaft; (b) a generator having a rotor shaft coupled coaxially with the wheel shaft of the first exhaust turbine; (c) a converter operatively connected to the generator for converting alternating current into direct current; (d) an inverter operatively connected to the converter for converting direct current into alternating current; (e) a motor having a rotatable shaft and drivable by the generator via the converter and the inverter; (f) means connecting the rotatable shaft of the motor to the output shaft of the thermally insulative engine. The energy of the exhaust gas recovered by the first exhaust turbine can be fed back to the output shaft of the thermally insulative engine through the generator, the converter, the inverter and the motor; (g) a body of silicon steel fitted over the rotor shaft of the generator; and (h) a stator coil, having a winding, for passing an armature current which is 90/sup 0/ advanced in phase through the winding to generate a no-load induced electromotive force, the generator thereby serving as a reluctance generator.
Kawamura, H.
Application of laser photoacoustic spectroscopy for the analysis of gas samples emitted by diesel engines
A homemade CO2 laser photoacoustic spectrometer has been constructed for monitoring gas emissions from several sources. Numerous air pollutant gases are emitted by the exhaust of industries, vehicles, power plants, etc. In Brazil, there has been an increasing demand for power generators, driven by diesel oil and other fossil fuels, because of the lack of rain and consequent decreased availability
D. U. Schramm; M. S. Sthel; M. G. da Silva; L. O. Carneiro; A. J. S. Junior; A. P. Souza; H. Vargas
Federal Oil and Gas: Interagency Committee Needs to Better Coordinate Research on Oil Pollution Prevention and Response.
Congress passed the Oil Pollution Act in 1990 (OPA). Among other things, OPA established the Interagency Coordinating Committee on Oil Pollution Research (interagency committee) to coordinate an oil pollution research program among federal agencies, inclu...
Determination of sulfur trioxide in engine exhaust.
Sulfur trioxide in the exhaust gas of an internal combustion engine is removed and concentrated by absorption in a solution of 80% isopropyl alcohol, which quantitatively absorbs it and inhibits the oxidation of any sulfur dioxide which may be absorbed. The absorbed sulfur trioxide (sulfuric acid) is determined by an absorption titration by using barium chloride as the titrant and thorin as the indicator. The sulfur dioxide content of the exhaust is measured continuously by means of a DuPont Model 411 ultraviolet photoanalyzer.
Arnold, D R
Near-IR optical process sensor for electric arc furnace pollution control and energy efficiency
12 An optical near-IR process sensor for electric arc furnace pollution control and energy efficiency has been proposed. A near-infrared laser has performed simultaneous in-situ measurements of CO (1577.97 nm), H2O (1577.8 nm and 1578.1 nm) and temperature in the exhaust gas region above a laboratory burner fueled with methane and propane. The applicable range of conditions tested is representative
Jason J. Nikkari; Murray J. Thomson
The ionized gas at the centre of IC 10: a possible localized chemical pollution by Wolf-Rayet stars
We present results from integral field spectroscopy with the Potsdam Multi-Aperture Spectrograph at the 3.5-m telescope at Calar Alto Observatory of the intense star-forming region [HL90] 111 at the centre of the starburst galaxy IC 10. We have obtained maps with a spatial sampling of 1 � 1 arcsec2= 3.9� 3.9 pc2 of different emission lines and analysed the extinction, physical conditions, nature of the ionization and chemical abundances of the ionized gas, as well determined locally the age of the most recent star formation event. By defining several apertures, we study the main integrated properties of some regions within [HL90] 111. Two contiguous spaxels show an unambiguous detection of the broad He II?4686 emission line, this feature seems to be produced by a single late-type WN star. We also report a probable N and He enrichment in the precise spaxels where the Wolf-Rayet (WR) features are detected. The enrichment pattern is roughly consistent with that expected for the pollution of the ejecta of a single or a very small number of WR stars. Furthermore, this chemical pollution is very localized (�2 arcsec �7.8 pc) and it should be difficult to detect in star-forming galaxies beyond the Local Volume. We also discuss the use of the most common empirical calibrations to estimate the oxygen abundances of the ionized gas in nearby galaxies from 2D spectroscopic data. The ionization degree of the gas plays an important role when applying these empirical methods, as they tend to give lower oxygen abundances with increasing ionization degree. Based on observations collected at the Centro Astr�nomico Hispano Alem�n (CAHA) at Calar Alto, operated jointly by the Max-Plank Institut f�r Astronomie and the Instituto de Astrof�sica de Andaluc�a (CSIC).Visiting Astronomer at the Instituto de Astrof�sica de Canarias.
L�pez-S�nchez, �. R.; Mesa-Delgado, A.; L�pez-Mart�n, L.; Esteban, C.
The Use of Mobile, Electrochemical Sensor Nodes for the Measurement of Personal Exposure to Gas-Phase Air Pollutants
In this paper we describe how low-cost, lightweight devices, which incorporate GPS and GPRS facilities and contain electrochemical sensors for carbon monoxide (CO), nitrogen monoxide (NO) and nitrogen dioxide (NO2), have been used to collect data representative of personal exposure to these important urban air pollutants. E.U. legislation has set target levels for gases thought to have adverse impacts on human health, and consequently led to a need for a more informed air pollution control policy. With many sites in the U.K. and in the rest of the E.U. still failing to meet annual targets for NO2, a need to better understand pollutant sources and behaviour has arisen. Moreover, while traditional chemiluminescence techniques provide precise measurements, the instruments are sparsely populated around urban centres and are thus limited in their ability to account for true personal exposure. Through a series of laboratory and field studies, it has been shown that electrochemical sensor nodes, when configured suitably and after post-processing of data, can provide selective, reproducible measurements, and that the devices have appropriate detection limits (at the low parts-per-billion level), as well as fast enough response times, for urban air quality studies. Both mobile nodes and their static analogues have been deployed with different aims. Static nodes have been used in dense networks in both the urban environment and in the grounds of a major international airport, as described in the partner papers of Mead et al and Bright et al. Mobile units are easily deployed in scalable networks for short-term studies on personal exposure; these studies have been carried out in a wide range of locations including Lagos, Kuala-Lumpur, London and Valencia. Data collected by both mobile and static sensor nodes illustrate the insufficiency of the existing infrastructure in accounting for both the spatial and temporal variability in air pollutants due to road traffic emissions, and thus also the potential insufficiency at quantifying the risks to health in the surrounding area. Recent campaigns with mobile sensor nodes have included attempts to probe the differences in personal exposure to gas-phase air pollutants at different heights of breathing zone and between different methods of transport.
Stewart, G.; Popoola, O. A.; Mead, M. I.; McKeating, S. J.; Calleja, M.; Hayes, M.; Baron, R. P.; Saffell, J.; Jones, R.
Chemistry and the Internal Combustion Engine II: Pollution Problems.
Discusses pollution problems which arise from the use of internal combustion (IC) engines in the United Kingdom (UK). The IC engine exhaust emissions, controlling IC engine pollution in the UK, and some future developments are also included. (HM)
Hunt, C. B.
Pollution: The Neglected Dimensions. Worldwatch Paper 27.
Although progress has been made in combatting the most visible and easily controlled forms of pollution (exhaust, industrial waste, sewage, etc.), other pollutants have been largely ignored. Pollutants which are uncontrolled and which are increasingly recognized as dangerous include carbon dioxide, toxic substances such as dioxin, mirex, lindane,�
Hayes, Denis
Exterior view of boiler house looking southwest with steam exhaust ...
Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey
Exterior view of boiler house looking southwest with steam exhaust vents in foreground. Engine house is on left. - Burnsville Natural Gas Pumping Station, Saratoga Avenue between Little Kanawha River & C&O Railroad line, Burnsville, Braxton County, WV
Comparing the CO Content of Cigarette Smoke and Auto Exhaust
This lab exercise investigates and compares the carbon monoxide content of automobile exhaust and cigarette smoke. The experiment uses gas chromatography with thermal conductivity detection to analyze the percentage by volume concentrations found in cigar
Jaffe, Dan; Chavasse, Laurie
Computational Aero-Acoustic Studies of an Exhaust Diffuser.
The present paper describes work underway to develop a computational approach that can adequately simulate both the aerodynamic and acoustic behavior of a typical exhaust diffuser/volute combination, such as are commonly used in industrial gas turbines fo...
B. A. Petersson C. Jayatunga G. Kroeff J. F. Carrotte J. J. McGuirk
Toxic Acid Gas Absorber Design Considerations for Air Pollution Control in Process Industries
This paper analyses the design parameters for an absorber used for removal of toxic acid gas (in particular sulfur dioxide) from a process gas stream for environmental health protection purposes. Starting from the equilibrium data, Henry's law constant was determined from the slope of the y-x diagram. Based on mass balances across the absorber,�
Manyele, S. V.
Applications for activated carbons from waste tires: Natural gas storage and air pollution control
USGS Publications Warehouse
Natural gas storage for natural gas vehicles and the separation and removal of gaseous contaminants from gas streams represent two emerging applications for carbon adsorbents. A possible precursor for such adsorbents is waste tires. In this study, activated carbon has been developed from waste tires and tested for its methane storage capacity and SO2 removal from a simulated flue-gas. Tire-derived carbons exhibit methane adsorption capacities (g/g) within 10% of a relatively expensive commercial activated carbon; however, their methane storage capacities (Vm/Vs) are almost 60% lower. The unactivated tire char exhibits SO2 adsorption kinetics similar to a commercial carbon used for flue-gas clean-up. Copyright ?? 1996 Elsevier Science Ltd.
Brady, T. A.; Rostam-Abadi, M.; Rood, M. J.
Recent developments and applications with gas cell correlation spectrometer. [IR sensing of air pollution
Gaspec, a gas filter correlation spectrometer, is described. Gaspec is a dual-gas three-channel instrument using two detectors which receive amplitude-shared source signals modulated at the frequency of the chopper. Several units for operation around the 3-5 micron and the 8-15 micron region have been constructed, and gases such as CO2, CO, CH4, HCl, NO, and hydrazines can be detected. Advantages of Gaspec are considered with reference to improvements developed for the basic Cospec (gas cell correlation spectrometer) instrument.
Barringer, A. R.; Davies, J. H.; Floyd, G.
Transport of exhaust products in the near trail of a jet engine under atmospheric conditions
The transport of exhaust effluents and the possibility of water ice contrail formation are investigated under the specific fluid dynamical conditions in the near exhaust trail of a subsonic jet aircraft at cruise altitude. By means of a computational model describing the two-dimensional turbulent mixing of a single jet of hot exhaust gas with the atmosphere, representative results are discussed
B. K�rcher
Large eddy simulation of pollutant gas dispersion with buoyancy ejected from building into an urban street canyon.
The dispersion of buoyancy driven smoke soot and carbon monoxide (CO) gas, which was ejected out from side building into an urban street canyon with aspect ratio of 1 was investigated by large eddy simulation (LES) under a perpendicular wind flow. Strong buoyancy effect, which has not been revealed before, on such pollution dispersion in the street canyon was studied. The buoyancy release rate was 5 MW. The wind speed concerned ranged from 1 to 7.5m/s. The characteristics of flow pattern, distribution of smoke soot and temperature, CO concentration were revealed by the LES simulation. Dimensionless Froude number (Fr) was firstly introduced here to characterize the pollutant dispersion with buoyancy effect counteracting the wind. It was found that the flow pattern can be well categorized into three regimes. A regular characteristic large vortex was shown for the CO concentration contour when the wind velocity was higher than the critical re-entrainment value. A new formula was theoretically developed to show quantitatively that the critical re-entrainment wind velocities, u(c), for buoyancy source at different floors, were proportional to -1/3 power of the characteristic height. LES simulation results agreed well with theoretical analysis. The critical Froude number was found to be constant of 0.7. PMID:21216525
Hu, L H; Xu, Y; Zhu, W; Wu, L; Tang, F; Lu, K H
Investigation of NO(x) Removal from Small Engine Exhaust
Contribution of emissions from small engines to the air pollution is significant. Due to differences in operating conditions and economics, the pollution control systems designed for automobiles will be neither suitable nor economically feasible for use on small engines. The objective of this project was to find a catalyst for the removal of NOx from the exhaust of small engines which use a rich air to fuel ratio. The desired catalyst should be inexpensive so that the cost of the pollution control unit will be only a small fraction of the total equipment cost. The high cost of noble metals makes them too expensive for use as NOx catalyst for small engines. Catalytic reduction of NO can also be accomplished by base-metal oxide catalysts. The main disadvantage of base-metal catalysts is their deactivation by poisons and high temperatures. Requirements for the length of the life of the small engine exhaust catalysts are much less than those for automobile exhaust catalysts. Since there is no oxygen in the exhaust gases, reduction selectivity is not a problem. Also, the reducing exhaust gases might help prevent the harmful interactions of the catalyst with the support. For these reasons only the supported metal oxide catalysts were investigated in this project.
Akyurtlu, Ates; Akyurtlu, Jale F.
Investigation of NOx Removal from Small Engine Exhaust
Contribution of emissions from small engines to the air pollution is significant. Due to differences in operating conditions and economics, the pollution control systems designed for automobiles will be neither suitable nor economically feasible for use on small engines. The objective of this project was to find a catalyst for the removal of NOx from the exhaust of small engines which use a rich air to fuel ratio. The desired catalyst should be inexpensive so that the cost of the pollution control unit will be only a small fraction of the total equipment cost. The high cost of noble metals makes them too expensive for use as NOx catalyst for small engines. Catalytic reduction of Nitrogen Oxide (NO) can also be accomplished by base-metal oxide catalysts. The main disadvantage of base-metal catalysts is their deactivation by poisons and high temperatures. Requirements for the length of the life of the small engine exhaust catalysts are much less than those for automobile exhaust catalysts. Since there is no oxygen in the exhaust gases, reduction selectivity is not a problem. Also, the reducing exhaust gases might help prevent the harmful interactions of the catalyst with the support. For these reasons only the supported metal oxide catalysts were investigated in this project.
Involvement of sensory nerves and TRPV1 receptors in the rat airway inflammatory response to two environment pollutants: diesel exhaust particles (DEP) and 1,2-naphthoquinone (1,2-NQ)
The environmental chemical 1,2-naphthoquinone (1,2-NQ) is implicated in the exacerbation of airways diseases induced by exposure\\u000a to diesel exhaust particles (DEP), which involves a neurogenic-mediated mechanism. Plasma extravasation in trachea, main bronchus\\u000a and lung was measured as the local 125I-bovine albumin accumulation. RT-PCR quantification of TRPV1 and tachykinin (NK1 and NK2) receptor gene expression were investigated in main bronchus. Intratracheal
Aila Mirtes Teles; Yoshito Kumagai; Susan D. Brain; Simone A. Teixeira; Ana A. Varriano; Maria Alice A. G. Barreto; Wothan Tavares de Lima; Edson Antunes; Marcelo N. Muscar�; Soraia K. P. Costa
Fast monitoring of motor exhaust components by resonant multi-photon ionisation and time-of-flight mass spectrometry
A new analytical procedure is provided by the combination of two types of spectroscopy. Resonant ionization of selected compounds by multiphoton ionization is based on results of absorption spectroscopy for the compound molecules of interest and time-of-flight mass spectrometry serves for the unambigious detection of these compounds. An interesting application of this method is the fast exhaust gas analysis. In the development of future combustion engines, the management of dynamic motor processes becomes predominant because by more than 90 % of all the dangerous exhaust pollutions are produced in instationary motor phases such as fast speed or load changes. The investigation of dynamic processes however, requires fast analytical procedures with millisecond time resolution together with the capability to measure individual components in a very complex gas mixture The objectives for a development project of such an instrument were set by the Research Association for Combustion Engines (Forschungsvereinigung Verbrennungskraftmaschinen, FVV, Germany): Up to ten substances should be monitored synchroneously with a time resolution of about 10 milliseconds, with concentration limits of 1 part per million and with a precision better than 10 % relative standard deviation. Such a laser mass spectrometer for fast multi-component automotive exhaust analyses has been developed in a joint research project by Bruker-Franzen Analytik GmbH, Dornier GmbH and the Technical University of Munich. The system has been applied at a motor test facility to investigate the emissions of the aromatic hydrocarbons benzene, toluene and xylene, of nitric oxide and acetaldehyde in stationary and dynamic engine operation. These measurements demonstrate that strong emission of these pollutants takes place at instationary engine operation and in particular that these compounds are emitted at different times, giving new information about the processes in the combustion chamber and in the exhaust pipe.
Franzen, Jochen; Frey, R�diger; Nagel, Holger
Hypercholesterolemia potentiates aortic endothelial response to inhaled diesel exhaust
Background Inhalation of diesel exhaust induces vascular effects including impaired endothelial function and increased atherosclerosis. Objective To examine the in vivo effects of subchronic diesel exhaust exposure on endothelial cell transcriptional responses in the presence of hypercholesterolemia. Methods ApoE (?/?) and ApoE (+/+) mice inhaled diesel exhaust diluted to particulate matter levels of 300 or 1000 ?g/m3 vs. filtered air. After 30 days, endothelial cells were harvested from dispersed aortic cells by fluorescent-activated cell sorting (FACS). Relative mRNA abundance was evaluated by microarray analysis to measure strain-specific transcriptional responses in mice exposed to dilute diesel exhaust vs. filtered air. Results Forty-nine transcripts were significantly dysregulated by >2.8-fold in the endothelium of ApoE (?/?) mice receiving diesel exhaust at 300 or 1000 ?g/m3. These included transcripts with roles in plasminogen activation, endothelial permeability, inflammation, genomic stability, and atherosclerosis; similar responses were not observed in ApoE (+/+) mice. Conclusions The potentiation of diesel exhaust-related endothelial gene regulation by hypercholesterolemia helps to explain air pollution-induced vascular effects in animals and humans. The observed regulated transcripts implicate pathways important in the acceleration of atherosclerosis by air pollution.
Maresh, J. Gregory; Campen, Matthew J.; Reed, Matthew D.; Darrow, April L.; Shohet, Ralph V.
[Evaluation of treatment technology of odor pollution source in petrochemical industry].
Using an environmental technology assessment system, we put forward the evaluation index system for treatment technology of the typical odor pollution sources in the petroleum refining process, which has been applied in the assessment of the industrial technology. And then the best available techniques are selected for emissions of gas refinery sewage treatment plant, headspace gas of acidic water jars, headspace gas of cold coke jugs/intermediate oil tank/dirty oil tank, exhaust of oxidative sweetening, and vapors of loading and unloading oil. PMID:24640922
Mu, Gui-Qin; Sui, Li-Hua; Guo, Ya-Feng; Ma, Chuan-Jun; Yang, Wen-Yu; Gao, Yang
Diesel Exhaust Exposure, Wheezing and Sneezing
The rising incidence of allergic disorders in developed countries is unexplained. Exposure to traffic related air pollutants may be an important cause of wheezing and asthma in childhood. Experimental evidence from human studies suggests that diesel exhaust particles, constituents of fine particulate matter less than 2.5 microns (PM2.5), may act to enhance IgE mediated aeroallergen sensitization and Th2 directed cytokine responses. To date, epidemiologic investigations indicate that children living in close proximity to heavily travelled roads are more likely to be atopic and wheeze. The Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) birth cohort study was initiated to test the hypothesis that early high exposure to traffic related air pollutants is associated with early aeroallergen sensitization and allergic respiratory phenotypes. Using an exposure cohort design, more than 700 infants born to atopic parents were recruited at age 1 living either less than 400 meters (high traffic pollutant exposure) or greater than 1,500 meters (low exposure) from a major road. Children were medically evaluated and underwent skin prick testing with aeroallergen at screening, and re-evaluated sequentially at ages 1, 2, 3, 4, and 7. In this study, both proximity and land use regression (LUR) models of traffic air pollutant exposure have been assessed. Proximity to stop and go traffic with large concentrations of bus and truck traffic predicted persistent wheezing during infancy. The LUR model estimated elemental carbon attributable to traffic (ECAT) as a proxy for diesel exhaust particulate exposure. High ECAT was significantly associated with wheezing at age 1 as well as persistent wheezing at age 3. High mold exposure predicted a well defined asthma phenotype at age 7.
Exacerbation of allergic inflammation in mice exposed to diesel exhaust particles prior to viral infection.
Background: Viral infections and exposure to oxidant air pollutants are two ofthe most important inducers ofasthma exacerbation. Our previous studies have demonstrated that exposure to diesel exhaust increases the susceptibility to influenza virus infections both in epithelial ce...
Diesel Exhaust Exposure and Nasal Response to Attenuated Influenza in Normal and Allergic Volunteers
Rationale: Diesel exhaust enhances allergic inflammation, and pollutants are associated with heightened susceptibility to viral respiratory infections. The effects of combined diesel and virus exposure in humans are unknown. Objective: Test whether acute exposure to diesel modif...
Simple vacuum pump exhaust filter
A simple vacuum pump exhaust filter based upon an automotive air cleaner has been constructed and tested. The major virtues of the filter system are ease of coupling to an external exhaust and the availability of filter elements.
Richard A. Forman; Harvey D. Kratz
40 CFR 87.31 - Standards for exhaust emissions.
...Exhaust Emissions (In-Use Aircraft Gas Turbine Engines) § 87.31 Standards for...of smoke from each in-use aircraft gas turbine engine of Class T8, beginning February...of smoke from each in-use aircraft gas turbine engine of class TF and of rated...
14 CFR 34.21 - Standards for exhaust emissions.
Code of Federal Regulations, 2011 CFR
...emissions of smoke from each new aircraft gas turbine engine of class...emission of smoke from each new aircraft gas turbine engine of class...exhaust emissions from each new aircraft gas turbine engine shall not...of this section refer to a composite gaseous emission...
Polycyclic aromatic hydrocarbon exhaust emissions from different reformulated diesel fuels and engine operating conditions
The study of light-duty diesel engine exhaust emissions is important due to their impact on atmospheric chemistry and air pollution. In this study, both the gas and the particulate phase of fuel exhaust were analyzed to investigate the effects of diesel reformulation and engine operating parameters. The research was focused on polycyclic aromatic hydrocarbon (PAH) compounds on particulate phase due to their high toxicity. These were analyzed using a gas chromatography-mass spectrometry (GC-MS) methodology. Although PAH profiles changed for diesel fuels with low-sulfur content and different percentages of aromatic hydrocarbons (5-25%), no significant differences for total PAH concentrations were detected. However, rape oil methyl ester biodiesel showed a greater number of PAH compounds, but in lower concentrations (close to 50%) than the reformulated diesel fuels. In addition, four engine operating conditions were evaluated, and the results showed that, during cold start, higher concentrations were observed for high molecular weight PAHs than during idling cycle and that the acceleration cycles provided higher concentrations than the steady-state conditions. Correlations between particulate PAHs and gas phase products were also observed. The emission of PAH compounds from the incomplete combustion of diesel fuel depended greatly on the source of the fuel and the driving patterns.
Borr�s, Esther; Tortajada-Genaro, Luis A.; V�zquez, Monica; Zielinska, Barbara
Lethal methemoglobinemia and automobile exhaust inhalation.
Inhalation of automobile exhaust gas often leads to death by CO intoxication. In some cases the measured carbon monoxide hemoglobin saturation level (COHb) is considerably below what is considered to be lethal. The death in such cases has been attributed to a combination of a high CO2 and a low O2 tension. In a recent case the deceased was found dead in a car equipped with a catalytic converter, with a hose leading exhaust from the engine to the interior of the car. Analysis revealed a moderately elevated COHb and a high methemoglobin saturation level (MetHb) in peripheral blood. No ethanol, narcotics or drugs were detected. Reports mentioning MetHb or methemoglobinemia in post-mortem cases are surprisingly scarce, and very few have related exhaust gas deaths to methemoglobinemia. High-degree methemoglobinemia causes serious tissue hypoxia leading to unconsciousness, arrhythmia and death. The existing literature in this field and the knowledge that exhaust fumes contain nitrogen oxide gases (NOx) that by inhalation and absorption can result in severe methemoglobinemia, led us to postulate that this death could possibly be attributed to a combination of methemoglobinemia and a moderately high COHb concentration. PMID:19261402
Vevelstad, Merete; Morild, Inge
Prevention of fog in the condensation of vapour from mixtures with inert gas, by a regenerative thermal process
In processing, vapours often have to be separated from mixtures mainly containing inert gas, as for example in the cleaning of exhaust air and the recovery of pollutant solvent vapours (volatile organic compounds, VOC). Whenever possible, condensation is applied for this task, since it is thermodynamically the most energy-efficient process. It can be carried out successfully, provided that the vapour
Stephan Kaufmann; Karl Hilfiker
Diesel exhaust rapidly degrades floral odours used by honeybees.
Honeybees utilise floral odours when foraging for flowers; we investigated whether diesel exhaust pollution could interrupt these floral odour stimuli. A synthetic blend of eight floral chemicals, identified from oilseed rape, was exposed to diesel exhaust pollution. Within one minute of exposure the abundances of four of the chemicals were significantly lowered, with two components rendered undetectable. Honeybees were trained to recognise the full synthetic odour mix; altering the blend, by removing the two chemicals rendered undetectable, significantly reduced the ability of the trained honeybees to recognize the altered odour. Furthermore, we found that at environmentally relevant levels the mono-nitrogen oxide (NOx) fraction of the exhaust gases was a key facilitator of this odour degradation. Such changes in recognition may impact upon a honeybee's foraging efficiency and therefore the pollination services that they provide. PMID:24091789
Girling, Robbie D; Lusebrink, Inka; Farthing, Emily; Newman, Tracey A; Poppy, Guy M
A method for reducing exhaust pressure of vehicle compressed air powered engine
Compressed air powered engine is a type of zero-pollution engine, but its conversion efficiency is very low for its high pressure exhaust which causes much exergy loss. In this study, a control system was developed to reduce the exhaust pressure of vehicle compressed air powered engine. The control system is made up of a controller, a pressure sensor, a photoelectric
Zhenggang Xu; Xiaopeng Xie
Diesel exhaust is a major source of pollution especially in urban areas. The contribution of the diesel exhaust particles and gases to increases in deaths, asthma symptoms, lung infections, and other health effects is unclear. This study will examine the lung, blood, heart, and o...
Effects of the biodiesel blend fuel on aldehyde emissions from diesel engine exhaust
Interest in use of biodiesel fuels derived from vegetable oils or animal fats as alternative fuels for petroleum-based diesels has increased due to biodiesels having similar properties of those of diesels, and characteristics of renewability, biodegradability and potential beneficial effects on exhaust emissions. Generally, exhaust emissions of regulated pollutants are widely studied and the results favor biodiesels on CO, HC
Chiung-Yu Peng; Hsi-Hsien Yang; Cheng-Hang Lan; Shu-Mei Chien
There are a variety of intrinsic as well as extrinsic factors, such as exposure to air pollution that can affect the pathogenesis of respiratory infections. Exposure to diesel exhaust (DE) emissions can alter host defense and immune responses and we have previously demonstrated t...
Dioxin-receptor Ligands in Urban Air and Vehicle Exhaust
The ability of extracts of urban air and vehicle exhaust particulates to bind to the dioxin receptor has been determined. It was shown that such extracts do contain significant amounts of dioxin-receptor binding activity. The level of dioxin-receptor binding found in ambient air reflects its pollution level as determined by mutagenic activity. Furthermore, it was shown that the extracts of
Grant G. F. Mason
Numerous studies have shown that air pollutants including diesel exhaust (DE) alter host defense responses, resulting in decreased resistance to respiratory infection. The purpose of this study was to evaluate the effects of DE exposure on the severity of an ongoing influenza in...
A Technique for the Analysis of Auto Exhaust.
Developed for presentation at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971, this outline explains a technique for separating the complex mixture of hydrocarbons contained in automotive exhausts. A Golay column and subambient temperature programming technique are�
Sothern, Ray D.; And Others
Multi-scale Measurements and Modeling of Greenhouse Gas and Pollutant Emissions from Coal Power Plants and Gas Mining at Four Corners
Accurate knowledge of emissions at multiple spatial and temporal scales is indispensable to air quality and climate change research and energy policy. The Four Corners, NM region contains two large coal-fired power plants with real-time in-stack CO2 and pollution monitors making it an ideal site to evaluate top-down verification methods. The air in this region is very polluted and technologies to reduce emissions are being implemented. It also has extensive gas mining with associated fugitive CH4 leaks. We have developed a comprehensive test-bed monitoring site near Farmington, NM that includes a solar Fourier Transform Spectrometer (TCCON) and a solar grating spectrometer (Pandora) to monitor column abundance of greenhouse gases (CO2, CH4, N2O) and pollutants (CO and NO2). We also monitor these trace gases and some isotopes (13CO2 and 13CH4) in situ by cavity ring-down and standard EPA pollution monitors together. In addition we monitor meteorology, boundary layer height and aerosol optical depth. We have made continuous measurements for over 16 months. To interpret our data we have coupled a high-resolution plume model to a nested Weather Research and Forecasting Model with Chemistry. Hourly real-time emissions are taken from in- stack monitors and other spatio-temporally resolved inventories. Our multi-scale forward model simulations are compared with our observations. We report observed power-plant signals, their diurnal cycles, and how they depend on local meteorology. Typically, the total-column in CO2 increases by 2 to 8 ppm when a power-plant plume is blowing towards our site, while the in situ CO2 increases by 10 to 50 ppm. We report the highest columnar measurements of NO2 measured (> 3 DU) and the first remote observations of columnar ratio of NO2/CO2 and 13CO2. Observations of NO2/CO2 and ?13CO2 are used to isolate power plant sources and constrain emissions. In situ CH4 measurements reveal large nocturnal increases of 4 to 5 ppm that could be from extensive fossil fuel mining activities that are missing in inventories. Finally, we examine satellite data (CO2 and CH4 from GOSAT and SCIAMACHY and NO2 from OMI) for signals over Four Corners for verification and longer-term trend analysis.
Dubey, M. K.; Lindenmaier, R.; Henderson, B. G.; Costigan, K. R.; Lee, S.; Herman, J. R.; Love, S. P.; Rahn, T.; Arata, C.; Butterfield, Z.; Chylek, P.; Reisner, J.; Porch, W.
Method of controlling temperature of a thermoelectric generator in an exhaust system
A method of controlling the temperature of a thermoelectric generator (TEG) in an exhaust system of an engine is provided. The method includes determining the temperature of the heated side of the TEG, determining exhaust gas flow rate through the TEG, and determining the exhaust gas temperature through the TEG. A rate of change in temperature of the heated side of the TEG is predicted based on the determined temperature, the determined exhaust gas flow rate, and the determined exhaust gas temperature through the TEG. Using the predicted rate of change of temperature of the heated side, exhaust gas flow rate through the TEG is calculated that will result in a maximum temperature of the heated side of the TEG less than a predetermined critical temperature given the predicted rate of change in temperature of the heated side of the TEG. A corresponding apparatus is provided.
Prior, Gregory P; Reynolds, Michael G; Cowgill, Joshua D
Gas-aerosol partitioning of semi volatile carbonyls in polluted atmosphere in Hachioji, Tokyo
Gaseous and particulate semi volatile carbonyls have been measured in urban air using an annular denuder sampling system. Three dicarbonyls, five aliphatic aldehydes and two hydroxy carbonyls were observed. Concentrations of other biogenic and anthropogenic volatile organic compounds (VOCs), SO2, CO, NO2 and particle concentration were also measured. Estimated gas-aerosol equilibrium constants for the carbonyls showed an inverse correlation with
Sou N. Matsunaga; Shungo Kato; Ayako Yoshino; Jim P. Greenberg; Yoshizumi Kajii; Alex B. Guenther
Reliability of Flue Gas Desulphurisation Installations - the Essential Condition of Efficient Air Pollution Control
In order to minimise the adverse effects of SO2 and SO3 on the environment, many power plants and industrial facilities use flue gas desulphurisation (FGD) scrubbers to remove SO2 and SO3 from combustion gases. The conditions within a scrubber and accompanying installations are very severe and cause corrosion problems for common engineering materials. Failures impend over the environment for lengthy
A. Miszczyk; K. Darowicki
The report describes tests to demonstrate the feasibility of using a vertical-tube, falling-film, vapor-compression evaporator to concentrate waste water from a flue gas desulfurization (FGD) process. Tests showed that waste water from the Chiyoda FGD process can be concentrated ...
The paper discusses both municipal waste combustor (MWC) rules and basic dry flue gas cleaning (FCC) processes, and compares the performance of the latter using field test data. Methods to supplement dry FCC processes for improving the control of mercury and organics are addresse...
Methanator Fueled Engines for Pollution Control.
A methanator fueled Otto-cycle engine is compared with other methods proposed to control pollution due to automobile exhaust emissions. The comparison is made with respect to state of development, emission factors, capital cost, operational and maintenanc...
D. E. Cagliostro E. L. Winkler
TOF-SIMS measurements for toxic air pollutants adsorbed on the surface of airborne particles
Three kinds of particulate matter were collected: diesel and gasoline exhaust particles emitted directly from exhaust nozzle, and suspended particulate matter (SPM) near the traffic route. Soxhlet extraction was performed on each sample. By gas-chromatograph-mass spectrometer (GC-MS) analysis of these extracts, di-ethyl phthalate and di- n-butyl phthalate were detected from the extract of SPM and diesel exhaust particles (DEPs). Because these phthalates were sometimes suspected as contamination, time-of-flight secondary ion mass spectrometry (TOF-SIMS) measurements were also performed on the samples collected at the same environment. By comparing obtained spectra, it is clear that these environmental endocrine disrupters (EEDs) were adsorbed on DEP surface. Thus, we concluded that the combination of conventional method and TOF-SIMS measurement is one of the most powerful techniques for analyzing the toxic air pollutants adsorbed on SPM surface.
Tomiyasu, Bunbunoshin; Hoshi, Takahiro; Owari, Masanori; Nihei, Yoshimasa
Contribution of solid fuel, gas combustion or tobacco smoke to indoor air pollutant concentrations in Irish and Scottish homes
There are limited data describing pollutant levels inside homes that burn solid fuel within developed country settings with most studies describing test conditions or the effect of interventions. This study recruited homes in Ireland and Scotland where open combustion processes take place. Open combustion was classified as coal, peat or wood fuel burning, use of a gas cooker or stove, or where there is at least one resident smoker. 24-hour data on airborne concentrations of particulate matter less than 2.5 microns in size (PM2.5), carbon monoxide (CO), endotoxin in inhalable dust and carbon dioxide (CO2), together with 2�3 week averaged concentrations of nitrogen dioxide (NO2) were collected in 100 houses during the winter and spring of 2009�2010. The geometric mean of the 24-hour time-weighted-average (TWA) PM2.5 concentration was highest in homes with resident smokers (99?g/m3 � much higher than the WHO 24-hour guidance value of 25 ?g/m3. Lower geometric mean 24-hour TWA levels were found in homes that burned coal (7 ?g/m3) or wood (6 ?g/m3) and in homes with gas cookers (7 ?g/m3). In peat-burning homes the average 24-hourPM2.5 level recorded was 11 ?g/m3. Airborne endotoxin, CO, CO2 and NO2 concentrations were generally within indoor air quality guidance levels.
Semple, S; Garden, C; Coggins, M; Galea, KS; Whelan, P; Cowie, H; Sanchez-Jimenez, A; Thorne, PS; Hurley, JF; Ayres, JG
Exhaust emissions from uncontrolled vehicles and related equipment using internal combustion engines. Part 6. Gas turbine electric utility power plants. Final report
Emissions data derived from laboratory and field test findings reported in the literature are sumarized for gas turbine electric utility power plants. The data are utilized together with information on the location and population of the plants to estimate national emissions impact, based on usage as reported to the Federal Power Commission. Expressing emissions from electric utility turbines as percentages
C. T. Hare; K. J. Springer
Pollutant emissions reduction and performance optimization of an industrial radiant tube burner
This paper presents the results of an experimental investigation performed upon a single-ended self-recuperative radiant tube burner fuelled by natural gas in the non-premixed mode, which is used in the steel industry for surface treatment. The main goal of the research activity was a systematic investigation of the burner aimed to find the best operating conditions in terms of optimum equivalence ratio, thermal power and lower pollutant emissions. The analysis, which focused on the main parameters influencing the thermal efficiency and pollutant emissions at the exhaust (NO{sub x} and CO), has been carried out for different operating conditions of the burner: input thermal powers from 12.8 up to 18kW and equivalence ratio from 0.5 (very lean flame) to 0.95 (quasi-stoichiometric condition). To significantly reduce pollutant emissions ensuring at the same time the thermal requirements of the heating process, it has been developed a new burner configuration, in which a fraction of the exhaust gases recirculates in the main combustion region through a variable gap between the burner efflux and the inner flame tube. This internal recirculation mechanism (exhaust gases recirculation, EGR) has been favoured through the addition of a pre-combustion chamber terminated by a converging nozzle acting as a mixing/ejector to promote exhaust gas entrainment into the flame tube. The most important result of this solution was a decrease of NO{sub x} emissions at the exhaust of the order of 50% with respect to the original burner geometry, for a wide range of thermal power and equivalence ratio. (author)
Scribano, Gianfranco; Solero, Giulio; Coghe, Aldo [Dipartimento di Energetica, Politecnico di Milano, via La Masa, 34, 20156 Milano (Italy)
Exhaust pressure pulsation observation from turbocharger instantaneous speed measurement
In internal combustion engines, instantaneous exhaust pressure measurements are difficult to perform in a production environment. The high temperature of the exhaust manifold and its pulsating character make its application to exhaust gas recirculation control algorithms impossible. In this paper an alternative method for estimating the exhaust pressure pulsation is presented. A numerical model is built which enables the exhaust pressure pulses to be predicted from instantaneous turbocharger speed measurements. Although the model is data based, a theoretical description of the process is also provided. This combined approach makes it possible to export the model for different engine operating points. Also, compressor contribution in the turbocharger speed pulsation is discussed extensively. The compressor contribution is initially neglected, and effects of this simplified approach are analysed.
Maci�n, V.; Luj�n, J. M.; Berm�dez, V.; Guardiola, C.
Acoustic Optimization of Automotive Exhaust Heat Thermoelectric Generator
The potential for thermoelectric exhaust heat recovery in vehicles has been increasing with recent advances in the efficiency of thermoelectric generators (TEGs). This study analyzes the acoustic attenuation performance of exhaust-based TEGs. The acoustic characteristics of two different thermal designs of exhaust gas heat exchanger in TEGs are discussed in terms of transmission loss and acoustic insertion loss. GT-Power simulations and bench tests on a dynamometer with a high-performance production engine are carried out. Results indicate that the acoustic attenuation of TEGs could be determined and optimized. In addition, the feasibility of integration of exhaust-based TEGs and engine mufflers into the exhaust line is tested, which can help to reduce space and improve vehicle integration.
Su, C. Q.; Ye, B. Q.; Guo, X.; Hui, P.
Pollution Control
Pollution takes many forms, such as ground, air, and water pollution. To make the environment pleasant to live in, certain methods are needed to clean up pollution or, even better, to prevent it all together. Several technologies and engineering techniques are regularly employed to keep pollution in check.The Air Pollution Control Technology Handbook (1) takes an in-depth look at many types of systems used in control equipment. Although the link on the page only shows the table of contents, each entry is hyperlinked to the full text. The online version of the Pollution Engineering magazine (2) has news and information about environmental control issues. A monthly publication, it stresses the economic benefits that can be realized with proper practices. Eight environmental technology verification centers can be accessed from this Web site (3). Operated by the US Environmental Protection Agency (EPA), the centers focus on greenhouse gas technology, advanced monitoring systems, water quality protection, air pollution control, and more. Recycling is something that many people do to reduce waste, but few know what the process of recycling involves. This educational site (4) provides a good overview of aluminum, glass, plastic, and polycoat recycling. Brookhaven National Laboratory operates this page (5), which offers extensive information on its environmental research and technology focus areas. Some sections describe work in decontamination and decommissioning, waste form development, and risk assessment. On September 8, 2002, a news report reported that the air pollution in Hong Kong, which is notorious for poor air quality, reached an all-time high in August since monitoring began in 1995. Clear the Air (6) is a project that hopes to reverse this trend by introducing pollution control measures. The project's home page has information on the situation in Hong Kong, as well as facts about the risk of air pollution in general. Another news article (7) describes the recent construction of a computer shredding plant in Chicago. Since computer disposal is a major problem in the US, recycling this technological waste is increasingly important. The operation of the system is quite impressive. The Global Environment Centre Foundation's Environmental Technology Database (8) has specifications and documentation on many types of pollution control equipment and technologies. Much of the information is about Japanese applications.
Leske, Cavin.
Inverse gas chromatographic characterization of Porapak Q as an extractant of pollutants from aqueous media
The surface of Porapak Q was characterized by inverse gas chromatography (IGC) carried out by the determination of dispersive\\u000a and specific adsorption components of Porapak Q surface, calculating ?sd and -?H\\u000a as parameters, respectively. An interpretation was given based on the chemical structure of Porapak Q. The obtained results\\u000a were confirmed through the surface Lewis acidity and basicity constants, K
Nagy E. Moustafa; Doaa S. El-Desouki
EVERGREEN: Global satellite observations of greenhouse gas emissions and air pollution
The EVERGREEN project of the European Commission 5 th Framework Programme has demonstrated new methods able to exploit satellite data in global climate and local air pollution research and application begin itemize item Global maps of CH4 CO and CO2 simultaneously measured were produced for the first time from SCIAMACHY space observations containing new information on sources and sinks item Major new methane sources in the tropics have been discovered which has lead to new research in methane emissions from plants item Global carbon monoxide data from SCIAMACHY and MOPITT have shown generally good agreement with models except for higher concentrations measured in Southern America These data have resulted in improved agreement with surface FTIR measurements tens of percent item Global carbon dioxide data from SCIAMACHY are in qualitative agreement with existing models and agree with the limited ground based FTIR stations to within a few percent item Variability in stratospheric methane measured by MIPAS was found to have a relatively small impact on the radiation budget 0 01 W m2 not exceeding the error bars Enhanced methane found by SCIAMACHY has a more significant effect on instantaneous radiative forcing 0 1W m2 depending on profile assumptions made item MOPITT data have been used to establish source sink strengths by inverse modelling item SCIAMACHY data have allowed inverse modelling of methane sources and sinks showing enhanced tropical emissions compared with a priory estimates end itemize Important new global atmospheric data sets
Goede, A. P. H.; Evergreen Consortium
Removal dynamics of nitric oxide (NO) pollutant gas by pulse-discharged plasma technique.
Nonthermal plasma technique has drawn extensive attentions for removal of air pollutants such as NO x and SO2. The NO removal mechanism in pulse discharged plasma is discussed in this paper. Emission spectra diagnosis indicates that the higher the discharge voltage is, the more the NO are removed and transformed into O, N, N2, NO2, and so forth. Plasma electron temperature T(e) is ranged from 6400?K at 2.4?kV discharge voltage to 9500?K at 4.8?kV. After establishing a zero-dimensional chemical reaction kinetic model, the major reaction paths are clarified as the electron collision dissociation of NO into N and O during discharge and followed by single substitution of N on NO to form N2 during and after discharge, compared with the small fraction of NO2 formed by oxidizing NO. The reaction directions can be adjusted by N2 additive, and the optimal N2/NO mixing ratio is 2?:?1. Such a ratio not only compensates the disadvantage of electron competitive consumption by the mixed N2, but also heightens the total NO removal extent through accelerating the NO oxidization process. PMID:24737985
Zhang, Lianshui; Wang, Xiaojun; Lai, Weidong; Cheng, Xueliang; Zhao, Kuifang
Spatial and Temporal Distributions of a Gaseous Pollutant During Simulated Preventive Maintenance and Pipe Leaking Events in a Working Cleanroom
Sulfur hexafluoride (SF6) of > 99.9% in purity was artificially released to simulate the emission sources in the etching\\/thin-film area of a working cleanroom in a semiconductor fab at the rate of 492 g\\/h. The temporal and spatial dispersion patterns of the gas pollutant were studied during the simulated preventive maintenance (PM) and pipe leaking exhaust events experimentally and numerically.
Shih-Hsuan Huang; Hui-Ya Shih; Shou-Nan Li; Sheng-Chieh Chen; Chuen-Jinn Tsai