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Problem Statement: What is the criteria for Ice form First in hydrate formation utility?
Solution: Ice Forms First is shown when the calculated hydrate temperature is lower than the freezing temperature of the stream. This freezing temperature is calculated by a proprietary internal method and is dependent on the type of impurity present in the aqueous phase. Specifically, if the fluid for which the hydrate temperature is being calculated contains methanol, ethylene glycol, di-ethylene glycol or tri-ethylene glycol, the freezing point is calculated based on freezing point depression curves for the each inhibitor. If no inhibitors are present, the freezing point is fixed at 32F. Keywords: Ice Forms First, hydrate formation, inhibitor References: None
Problem Statement: In the Fluid property package view | Tabular tab what is Use PPDS?
Solution: If you have the PPDS database, you may select the database by clicking the checkbox in the Use PPDS column. PPDS (Physical Properties Data System) is a pure component database provided by NEL (http://www.ppds.co.uk/). Please contact [email protected] if you require this databank. Keywords: PPDS, tabular References: None
Problem Statement: When double click on a Aspen HYSYS .hsc file in Windows Explorer, the file is opened in the default version of Aspen HYSYS. How can I set up the default version of Aspen HYSYS?
Solution: You have to register the version which you want to set up as a default version when you open any file. You can register the default version from the command prompt. Open the Administrator Command Prompt, go to C:\Program Files\AspenTech\Aspen HYSYS 2006.5, and type hysys /regserver. A pop-up window will say that it was successful. If the above procedure has not worked Open the Administrator Command Prompt and type the following including the quotations: C:\Program Files\Aspentech\Aspen HYSYS 2006.5\hysys /regserver For the versions later than 2004.2, i.e., 2006, 2006.5, V7.0, you can restore file association from Start | Program | Aspen engineering Suites | Aspen Hysys, and right-click on the Restore File Associations. After running Restore File Associations, whenever you double-click to open a HYSYS file, it will be opened in the default version. There is another way you can set up the default version of HYSYS. The steps are as follows: -You right click the file | select Open with option | then select Choose program and you will see the window like the snap shot below. You select any of Aspen HYSYS.Plant simulation software and click on check box of ?Always use the selected program to open this kind of file?. The only problem with this method is that you have to try one by one to get your preferred version as it does not show the version number directly. The referenceSolutions on the same issue are 119947,123977 and 124669. Keywords: open file, default, version, restore File Association, administrator, command prompt References: None
Problem Statement: Suppose the Define from Other Stream option was used to initialize a new stream. Later the model is developed into a non-trivial sized flowsheet. Given that the source stream ID is not recorded within the Aspen HYSYS simulation, is it possible to find the source stream where the current stream data was copied from?
Solution: Currently this information is not recorded as part of stream data. The idea here is to capture the identical elements between the original and the copy. If the temperature, pressure and compositions are copied, the temperature, pressure and molecular weight must be the same. If only compositions are copied, molecular weight must be the same. If we can tabulate temperature, pressure and molecular weight of all streams on PFD and sort the values of molecular weight, we can find the matching streams. The implementation of this idea is carried out using the available HYSYS Stream Reporter (KBSolution 110500 and 121701), an Excel workbook with macros. The user should select correct version of the HSR file and choose Temperature, Pressure and Molecular Weight as stream properties to generate the report table. The data on this table can be transposed so that one property occupies one column on spreadsheet. Lastly, a user can used Data | Sort to sort based on any of the selected properties. Detailed steps and screen shots are given in the attached Word file. Keywords: sorting, define, source, stream References: None
Problem Statement: When using the Fired API521 mode within the Depressuring Utility in HYSYS, if the C3 value is specified to 0, the results are the same as the adiabatic mode. This is inconsistent with the Dynamic Depressuring - A Practical Guide document, which states that if C3=0, the initial wetted area is used during the duty calculations.
Solution: The Dynamic Depressuring - A Practical Guide document corresponds to an earlier version of the Dynamic Depressurization Utility. Even though it is still a useful guide for the many aspects of the utility, some changes have been made to the application. Since v2004, the wetted area is no longer calculated by the stated equation: Wetted area(t)=Wetted area(0)*(1-C3*(1-LiqVol(t)/LiqVol(0))) [A] Instead, it is automatically calculated from the level in the vessel within (using the stream conditions and the vessel holdup). Also, the equation stated in the practical guide for the calculation of the Heat Flux in Fired Wetted mode has been replaced with the newer one which includes a different definition of the C3 parameter, Q=C1*(C3*WettedArea(t))^C2 [B] The C3 constant above does not correspond to the constant used in equation A and instead works as an Environmental factor used to de-rate the fire calculations due to mitigating circumstances (such as a partially buried vessel, etc.). The equivalence with the Environmental Factor, F, defined in the API521 is, F=C3^0.82 [C] Notice that when C3=0, no duty is applied and the Fired API521 reduces to the Adiabatic mode. Keywords: Depressuring, API521, Fired, Wetted, Equation References: None
Problem Statement: When I have different streams connected to a mixer and one of them has zero flow, the outlet stream does not have the same temperature as the feed stream with a flow.
Solution: When there is a material stream without a flow entering a mixer and this stream has a lower pressure that the other material streams entering the mixer, the outlet stream from the mixer shows a different temperature to the one expected. The reason for this could be that the mixer is using the lowest pressure of all streams entering the mixer to calculate the outlet temperature. A work-around could be to select the Equalize All option on the Design | Parameters page of the mixer to make all the pressures the same. Keywords: Pressure, Temperature, Mixer References: None
Problem Statement: How does one change the number of stages in a distillation column?
Solution: Two methodologies can be employed; change the total number of stages by supplying a new value in the Num of Stages entry box (on the Design | Connections tab) or click the Edit Trays button on the Design | Connections tab and provide required information. Changing the total number of stages results in Aspen HYSYS estimating feed locations by attempting to maintain stripping and rectifying stage ratios. This approach typically requires some addition input from the user in order to define the correct feed and draw locations. Using the Edit Trays button gives the user control over where the specific stages are removed and should not require further manipulation one complete. Keywords: Top, Bottom, Add, Remove, Tray, Stage, Column References: None
Problem Statement: How does one generate a cooling curve for an air cooler?
Solution: Starting with Aspen HYSYS V7.3 you can generate the cooling curve within the Air Cooler unit operation via the Performance tab (selecting the PLOTS page will display the curves in graphical format, whereas the TABLES page will display the results in a tabular form). For Aspen HYSYS V7.2 and lower versions the air cooler operation does not have the same functionality as the air cooler in V7.3 or heat exchanger unit operation in regards to the plotting of enthalpy curves. The simplest way to achieve a similar result from an air cooler in Aspen HYSYS V7.2 and lower version is to model the same heat transfer using a heat exchanger as in the attached case. Heating / cooling curves can be obtained for a heat exchanger in Aspen HYSYS via the Performance tab (selecting the PLOTS page will display the curves in graphical format, whereas the TABLES page will display the results in a tabular form). Note that selecting the Exchanger Design (Weighted) model from the Design | Parameters tab allows one to dictate how many intervals are used when generating the enthalpy curve. Keywords: Cooling Curve, Performance, Air Cooler References: None
Problem Statement: SQL Server 2005 SP3 is a pre-requisite for Aspen One V7.3 installation. However, installation of SQL Server 2005 SP3 failed. PC experiences rebooting problem.
Solution: This error occurs on a PC with Windows XP SP2 where user has added a manifest that has the Microsoft Windows Vista extension to an .exe or a .dll file. User needs to upgrade to Windows XP SP3. Alternatively, user can apply KB 921337 from Microsoft (http://support.microsoft.com/kb/921337). Keywords: Reboot, restart, SQL Server 2005 SP3 References: None
Problem Statement: How do I reset the sub-flowsheet for the depressuring Utility if I want to go to default subflowsheet? Sometimes, the user may have made changes directly in the subflowsheet associated with a depressuring utility. Here is a simple way to rebuild the subflowsheet.
Solution: The fix is to switch the fluid package for the subflowsheet to a different one. Afterwards, the subflowsheet will be recreated when clicking on Run in the depressuring utility, and the program will also reset the fluid package back to the default. Steps: 1. In Basic environment at Fluid Pkgs tab, change fluid package to a different one for the subflowsheet associated with the depressuring utility 2. In Simulation environment, open the depressuring utility and click on Run. Now the subflowsheet is recreated, and the fluid package for the subflowsheet is reset back to the default. 3. Click on Stop, and then click on Run again to complete the depressuring simulation. Keywords: Depressuring utility, subflowsheet, PFD, default References: None
Problem Statement: How do I get the Cloud point or Pour point of a stream?
Solution: Aspen HYSYS does not provide a standard method to calculate cloud point however, you can use some external correlations to calculate a value for each component in a User Variable, but this requires some programming knowledge. Or if you have the formula (ASTM 2500 may have a relevant equation), you can also create a Spreadsheet Unit Operation in HYSYS to calculate it. You can calculate the ASTM D97 Pour Point of a crude using Cold properties utility or Boiling Point Curves utility (Tools | Utilities | Cold Properties Utility or Boiling Point Curves Utility). If you have Aspen HYSYS Petroleum Refining (earlier Aspen RefSYS), then you can use the Petroleum correlations to report the Cloud point and Pour point of the crude using Petroleum correlations. To add the petroleum properties to a crude stream, open the stream property view and go to Worksheet | Properties and click the green + sign and expand the petroleum properties and select Cloud Point and Pour Point and click 'Apply'. You can then see these newly added properties in the bottom of the list in the stream properties window. Please note that petroleum properties may not work if Aspen HYSYS Petroleum Refining is not installed or not licensed, but you can try checking them. Keywords: Cloud point, Pour point References: None
Problem Statement: Definitions of Total Power Loss and Linker Power Loss specifications in Aspen HYSYS
Solution: The Total Power loss or Linker Power loss is applicable when linking a series of compressors and or expanders via a common shaft and is defined as: Where: WLinkLoss is the Linker power Loss; WExpander is the Expander duty; WCompressor is the Compressor duty. Total Power Loss specification is available for Steady State simulation and can be found under the Design tab and Links page. The Linker Power loss is used for Dynamic simulation and can be accessed via the Dynamics tab and Specs page. If the compression train does not contain an expander then Total Power loss/Link power loss specification should be negative which will be equal to the sum of the compressor duties. Keywords: Turbo-expander, Compressor Curves, Gear Ratio References: None
Problem Statement: What are the component names of p-Sulphide and b-Sulphide?
Solution: p-Sulphide = Di-n-Propyl-Sulfide or Di-n-Propyl-Sulphide. It's CAS number is 544-40-1. b-Sulphide = Di-n-Butyl-Sulfide or Di-n-Butyl-Sulphide. It's CAS number is 111-47-7. Keywords: p-sulphide, b-sulphide References: None
Problem Statement: Can the Fired Heater operation handle hypothetical components?
Solution: The Fired heater operation performs pure hydrocarbon combustion calculation only. Hypothetical components will not have heat of combustion value. As a result, Aspen HYSYS can not report the heating value and can not calculate heat of combustion for these products. Keywords: Fired Heater, hypothetical References: None
Problem Statement: I want to update the names of a large number of Aspen HYSYS operations and/or stream names which follow a regular naming pattern.
Solution: It is quite frequent to see the names of the streams and of the unit operations of large Aspen HYSYS models following a naming pattern and in some cases these names need to be updated manually. The Aspen HYSYS automation sample attached with the incident is a small MS Powershell script which can be used to automate the update of these names. Powershell scripting engine is available within the standard installation of the different editions of Windows 7 and MS Server 2008. For the different editions of Windows XP, Windows Vista and Windows Server 2003 machines, it can be downloaded from the link detailed next: http://support.microsoft.com/kb/968930 USAGE: 1. Verify Powershell is available in your system launching the powershel command prompt: Start | Run | Type Powershell and press OK 2. Verify the scripting engine is granted enough permissions to run the script file with the following command: Set-ExecutionPolicy RemoteSigned 3. Launch the attached script with a mouse double click or specifying the full path from the command prompt. PS C:\> G:\PS_FILES\01-PROG\HYSYS-BULK-TAG-RENAMING-SAMPLE.ps1 Keywords: HYSYS Automation, Powershell, renaming PFD elements References: None
Problem Statement: How do I model an isochoric flash in Aspen HYSYS? (eg: a system which is blocked in and remains at pressure whilst being cooled to ambient temperature)
Solution: There is no direct way to model isochoric (constant molar volume) flash in HYSYS, however one can use an Adjust operation to force the actual volume flow to be equal by either modifying the pressure or the temperature. The attached example demonstrates how one can find the final pressure reached once the system has cooled down -in this case cooled to 9?C from starting conditions of 148 bara and 19?C). To perform the simulation, one can use P-T flash and iterate over pressure meeting the isochoric conditions, i.e. constant molar volume. This can be done using the Adjust operation to meet the isochoric condition and a Case Study (Tools / Databook) to see the behavior of the system when temperature decreases. State1 represents here the final conditions, since the Case Study only works with positive step sizes. Keywords: Isochoric, flash calculation, adjust block References: None
Problem Statement: What sizing equations are used in Fisher valve of Depressuring Utility or valve?
Solution: In Depressuring utility, Fisher valve use the Universal Sizing equation instead of fisher equation in Fisher Manual. This equation model is very similar to the Fisher equation. The difference between the two is the backwards compatibility when the valve has both vapour and liquid flowing through. The Universal Sizing model uses the overall density. Universal Sizing method: For the gas flow through the valve, the equations are as follows: f = vfracfac 1.06 Cg (rho*P1)0.5 sin(arg) Where: arg = 59.64/C1 (1-P2/P1)0.5 *Cpfac With upper and lower limits: 0<Arg< p/2 C1=Cg/Cv Km=0.001434C1 Cpfac=(0.4839/(1-(2/(1+g))g/(g-1)))0.5 g=Cp/Cv f = flowrate, lb/hr rho = fluid density, lb/ft3 P1 = pressure of the inlet stream P2 = pressure of the exit stream without static head contributions vfracfac = 1, when outlet molar vapor fraction vfrac >0.1 = 0, when outlet molar vapor fraction vfrac =0 = vfrac/0.1, otherwise For the liquid flow through the valve, the equations are as follows: f = (1- vfracfac) 63.338 Cv (rho)0.5 (P1-P2) Keywords: Fisher valve, sizing equation, depressuring utility, valve References: None
Problem Statement: When linking Excel to Aspen HYSYS, there might be issues referencing the Aspen HYSYS type library. This
Solution: provides the steps to fix this problem.Solution To correct Aspen HYSYS type library reference in Excel you need the Administrator rights to the PC you are working. You also will need to make sure that the reference in the macros are referencing the correct version of Aspen HYSYS. That can be done following the steps given below: Open in excel the Macro view editor by hitting Alt+F11. From the VBA debugger navigate to Tools | Keywords: Restore File Association, HYSYS Type Library References: s and make sure that the Aspen HYSYS type library is the same as the version you are using. If the Aspen HYSYS type library is not the same as Aspen HYSYS version, then de-select the reference, click OK to close the references window, reopen it and select the correct reference. The Aspen HYSYS Type library is located on the Root Aspen HYSYS folder ussually under C:\Program Files\Aspentech\HYSYS version. See screenshot below for HYSYS 2006 type library. If this still doesn't help either run the attached script (choose the one that matches your version and change the extension from txt to bat) Otherwise, create a text file with the following code and change the line highlighted bit in yellow with the path to your version. C:\Program Files\AspenTech\Aspen HYSYS V7.2\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS V7.1\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS V7.0\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS 2006.5\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS 2006\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS 2004.2\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS 2004.1\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Aspen HYSYS 2004\hysys.exe /unregserverquietly C:\Program Files\AspenTech\Hyprotech\HYSYS 3.2\hysys.exe /unregserverquietly set myVersion=C:\Program Files\AspenTech\Aspen HYSYS V7.1 %myVersion%\Hysys.exe /regserverquietly pause
Problem Statement: Can I specify the Watson K Factor in Aspen HYSYS?
Solution: The user can directly specify the Watson K Factor in Aspen HYSYS. This is the default option in the program. If this value is not specified by the user, then the program automatically calculates the Watson K Factor. The Watson K Factor is used to characterize crude oils and crude oil fractions and it is defined as, Where; K = Watson K factor TB = normal average boiling point for the crude oil or crude oil fraction, ?R SGo = specific gravity of the crude oil or crude oil fraction Example; A particular kerosene cut, obtained over the boiling point range 284 - 482 ?F, has a specific gravity of 0.7966. Values of K typically range from about 11.5 to 12.4, although both lower and higher values are observed. In the absence of a known value, K = 11.9 represents a reasonable estimate. Keywords: Watson K Factor References: None
Problem Statement: How are the liquid levels defined in a separator with a boot for carry-over calculations?
Solution: For a separator with a boot, the liquid levels are defined based on the bottom of boot as datum. If heavy liquid is in the boot only, then the height of heavy liquid is height in the liquid in boot. For light liquid it will be Height of Boot+liquid level in vessel. When entered these into carryover calculations, HYSYS treats these levels in the following manner. heavy liquid level = heavy liquid level entered - boot height light liquid level = light liquid level entered - boot height Keywords: real separator, liquid height, heavy liquid, light liquid, boot. References: None
Problem Statement: Why are there drastic changes in outlet liquid streams after I add water in a three phase separator?
Solution: Addition of water can change the three phase separator's behavior significantly. For example you have light hydrocarbon and heavy hydrocarbon in liquid outlet streams of a three phase separator. If you add water, the aqueous phase will become the second liquid phase. The light and heavy hydrocarbon phases will combine to form one liquid phase. There will be some component distribution between the aqueous and liquid phase of course. If you want separate the two liquid phases you observed before adding water you need another three phase separator in series. Please use a a component separator to deduct enough water from the liquid phase of the first three phase separator so that an aqueous phase does not form or predicted and then feed it to the second three phase separator. As long as HYSYS detects aqueous phase as one liquid phase you will not see the other two liquid phases. There is a file attached with this document. If you make flow rate of Water 0 in one case and 100 kmol/h in the second you can observe the behavior in question. In the file the first separator observes an aqueous phase as one of the two liquid phases. The component splitter is removing water so that no aqueous phase is detected. The second separator finds two liquid phases (no aqueous phase). Keywords: Three phase separator, water References: None
Problem Statement: The D86 95% (Petrol) point calculated by property Correlation Manager and Boiling point utility are different.
Solution: In HYSYS, user should not apply D86 95% correlation on stream using property Correlation Manager because this will give a different D86 Petrol Point result than Boiling Point utility. In HYSYS only the Boiling Point utility and Cold Property utility will give correct D86 temperatures. In RefSYS, user can apply D86 95% correlation on stream and that will be consistent with Petroleum Assay utility. Boiling Point curve utility will be disabled for RefSYS in future version. This is because RefSYS treats HYPO NBP as final boiling point and HYSYS treats that as mid boiling point. Please note that petroleum properties will not work if Aspen RefSYS (Aspen HYSYS Petroleum Refining) is not installed or does not have license for this software. Keywords: D86 Point, Property Correlation Manager, Boiling Point Utility, Cold Property Utility References: None
Problem Statement: How to copy a material stream along with the utility (eg.depressuring utility) from one simulation file to another?
Solution: There can be a scenario where you need to copy a stream along with the attached utility from one large simulation to the other to continue further study on it. For example, you have a huge steady state simulation with large number of unit operations, subflowsheets and logical operators and want to carry out the depressuring studies on a stream in this simulation. Running a depressuring utility in a large flowsheet may complicate simulation further. This task can be simplified by exporting the stream along with the depressuring utility to a new simulation using the template feature available in Aspen HYSYS .To do this you will need to follow the steps given below. 1. Open the main simulation case. 2. Create a new stream. 3. Click on the Define from other stream and define that new stream from the stream connected to the depressuring utility. 4. Now delete everything away that is unrelated with the the depressurizing utility so that the main simulation has only the stream with the depressuring utility, the new stream created, and the depressuring utility subflowsheet. 5. If the original stream was a calculated one ( the variables on worksheet are black in colour), you will find that the original stream is not unconverged as we delete the unwanted attached unit operations. Open the stream linked to the depressurizing utility and click the define from other stream button and copy from new stream. 6. You can now delete the new stream. 7. Go to Simulation / Main Properties and select Convert to Template. 8. DO NOT SAVE THE CASE as you have deleted many items from the simulation. Save the template and close the case. 9. Open or create the new case and create a subflowsheet in the flowsheet selecting Read from Exiting Template. Pick the template you saved previously. 10. Select Yes, when asked for use the same fluid package. The stream along with the depressuring utility will be available in the new simulation. Keywords: Depressuring Utility, Template References: None
Problem Statement: Is it possible to specify and report volumetric flowrate at normal conditions using Aspen HYSYS?
Solution: To input volumetric flow rate in normal conditions (0C and 1 atm) choose Nm3/h as the unit when entering molar flowrate. To report calculated volumetric flow rates at normal conditions, open your session Preferences and select Nm3/h as the unit of measure for Std Gas Flow. Note that you will need to clone the existing unit set if you are using EuroSI, Field or SI as your current unit set. Keywords: normal, standard, flow, conditions References: None
Problem Statement: What's New in Aspen HYSYS V7.2 - New Functionality in Aspen Properties
Solution: Aspen HYSYS V7.0 introduced access to the Aspen Properties chemical compound databases and physical and chemical property calculation methods. This introduction more than doubled the thermodynamics capabilities of HYSYS, and made over 13,000 new compounds (mostly organic) available to HYSYS users. The enabled property methods can be used in HYSYS process calculations, thus extending the types of components and processes that can be modeled using Aspen HYSYS. For example, you can use the NRTL property methods in Aspen Properties to model highly non-ideal chemical systems, or the electrolyte NRTL property methods to model electrolyte systems. V7.2 includes new functionality that within Aspen Properties that is available now also to HYSYS users. New Electrolyte Models The Symmetric Electrolyte NRTL activity coefficient model has been added, with corresponding property method ENRTL-SR. This model calculates activity coefficients based on a symmetric reference state for ionic components of pure fused salts. This model possesses several advantages over the original Electrolyte NRTL model: In non-aqueous systems it removes the need to introduce water where there would otherwise be none. For mixed-solvent systems, this is more convenient than the reference state of infinite dilution in pure water used by the original Electrolyte NRTL model. This model calculates the Gibbs free energy and enthalpy from the same thermodynamic framework as the activity coefficient, rather than using mixing rules in systems with multiple electrolytes, as the original Electrolyte NRTL model did. This is more thermodynamically consistent for systems with multiple electrolytes, and in systems with no ions it is identical to NRTL-RK. The Unsymmetric Electrolyte NRTL activity coefficient model has been added, with corresponding property method ENRTL-RK. This model uses the same reference state for ions (infinite dilution in pure water) as the original Electrolyte NRTL, but uses the more consistent methods for calculating Gibbs free energy and enthalpy of the Symmetric Electrolyte NRTL model. For systems with a single electrolyte, this should be identical to Electrolyte NRTL. GERG2008 Equation of State for Light Gases The GERG2008 equation of state for natural gas has been added. This is a method designed for high accuracy of typical natural gas components and only those components, similar to REFPROP which is designed for a somewhat broader range of components. This is the 2008 extension to the GERG-2004 model. GERG2008 is a standard (ISO-20765) international reference equation suitable for all natural gas applications, including processing, transportation, and storage of natural gas. It is the accepted method used to calculate the flows of light gases at custody transfer points between companies, where money changes hands and highly accurate properties are required. New IAWPS-95 Steam Tables The IAPWS-95 steam tables has been added. IAPWS-95 is the current standard steam table from the International Association for the Properties of Water and Steam, which replaces the IAPS-84 steam table currently implemented as STEAMNBS. Benefits of the new steam tables include: More accurate near the critical region Valid up to 1000 ?C and 1000 MPa Accurate to within measurement error for such properties as density, isobaric heat capacity, and speed of sound Amines Data Package The methyl-amine data package has been updated to produce more accurate VLE results for methyl-amine, dimethyl-amine, and trimethyl-amine with water, ammonia, and methanol. It can be used within HYSYS by importing the property definition file generated by Aspen Properties or Aspen Plus into Aspen HYSYS.Solution ID #125517 provides information on how to do this. Keywords: Usability Improvements, What's New, New V.2 References: None
Problem Statement: How do I add the additional tabs in EDF file?
Solution: In order to add additional tabs in the EDF interface, you first click the bottom of tab and highlight the name of tabs. If you click the right button (P1), you select Page tabs properties . Figure: P1 You add additional tabs, for example: Parameters, Results tabs. You need assign a value for each tab (Parameters is 2 and Results is 3, see P2). Click OK. Figure: P2 Then, put your mouse on the interface and click right button. Select Open visibility manager and click Edit for page controller (see P3). Figure: P3 In visibility controller view, you add Parameters and Results. The integer value for both Low and High cells have to be the same and is consistent with value for each tab in the Static Tabs, which we just assign: 2 and 3 (see P4). Figure: P4 Keywords: Unit extension, EDF, Automation, Aspen Hysys References: None
Problem Statement: In new license file, we could not find any keys such as SLM_Extensions_OLGAS, SLM_Extensions_PIPESYS, SLM_HYSYS_OLGAS, SLM_HYSYS_OLGAS3P for OLGAS in Pipesys and pipesegment. Do we need any additional license keys from Aspentech to run OLGAS in PIPESYS after getting the license from SPT group in Hysys V7.2?
Solution: After October 31, 2010, AspenTech no longer offers the PIPESYS or OLGAS technologies from SPT Group as part of our aspenONE Engineering suite. Customers have to license either PIPESYS or OLGAS directly from SPT Group. Customer will need to install V7.2 CP2 and hotfix (130562) from the support site. After that it will work. Now there is no need to SLM license for OLGAS/Pipesys from Aspen Tech. Keywords: OLGAS, PIPESYS, pipe segment, SPT, license keys. References: None
Problem Statement: Results displayed in Aspen HYSYS do not match with the results displayed in the TEMA sheet when using HTFS or EDR to design the heat Exchanger. For example, - Results in HYSYS - Results in the TEMA Sheet
Solution: In HYSYS, open the Heat Exchanger window. Check the Ignored option at the bottom right of the window. Then uncheck it. The program will update the calculations and the results in the TEMA sheet will match the ones in HYSYS. Keywords: Heat Exchanger TEMA sheet Match results HYSYS References: None
Problem Statement: How does one view pure component properties if using the Aspen Properties database in Aspen HYSYS?
Solution: When using the Aspen Properties database in Aspen HYSYS, the component properties will not be displayed on the standard pure component property view. The properties of a given component can; however, be viewed by the following method: 1. Select the component of interest from the Component List and click the View button. 2. On the Component Property view that appears, click the Edit Properties button to view the details of all component properties. If you have multiple components in your Fluid Package and you would like to view the pure component properties for all components: 3. Click on the Edit Properties button at the bottom of the Fluid Package property view to see the complete details for all components. Keywords: Pure, Component, Aspen Properties, View, Properties References: None
Problem Statement: Why do the tray sizing utility and the rating tab have two different diameter or different results? Tray sizing utility and Rating tab show two different results. Which one should I trust?
Solution: Results of tray sizing or tray rating utility should be read from from the respective utility. It does not have any connection with the Rating tab in the column view window. The rating tab is for dynamic mode and not for tray sizing purpose. The rating tab contains default numbers. You have to change the diameter and tray/packed space in the rating tab manually. Keywords: Rating tab, rating, tray sizing utility. References: None
Problem Statement: What is Modified ASTM RVP method?
Solution: In V7.2 a new RVP correlation Modified ASTM is added to the list of RVP calculation methods. This method is a proprietary modification to the ASTM method based on the attached paper. Keywords: RVP, ASTM, Modified ASTM. References: None
Problem Statement: Can I create a Template in V7.3 and use it in an earlier version of an Economic Evaluation product (like V7.2)?
Solution: No you can not use a Template from V7.3 in any earlier versions of Economic Evaluator products. The Template feature is new to V7.3 and the earlier versions will not recognize it. Any Templates you create in V7.3 will be able to be used in future releases because they will also have the Template feature Keywords: None References: None
Problem Statement: Similar to Aspen Plus behavior, a HYSYS model that uses EO subflowsheet usually generates a number of temporary files in between runs. But unlike Aspen Plus, the temporary files are not in the same folder as the model file. Where are these files located on my hard drive?
Solution: They are located at the Temp folder of the logged-in users' profile folder, for example, C:\Documents and Settings\songt\Local Settings\Temp. Keywords: Temporary files, EO, equation oriented, Aspen Properties References: None
Problem Statement: Are there any example files describing Liquid - Liquid Extraction in Aspen HYSYS?
Solution: In the attached word document tutorial, a simple liquid-liquid extraction process in HYSYS is explained. A liquid stream containing 60 mol% water and 40 mol% acetone entering at 25 C, 1 atm, and flowing at a rate of 1 kgmol/s will be extracted with a pure MIBK stream at the same exact conditions as the feed. Keywords: Extraction, Liquid - Liquid Extraction, LL References: None
Problem Statement: I have developed extensions that I have added to my HYSYS simulations. I noticed that they show in the palette under the Custom section. Currently they show up as blank icons. How can I define my own icons to show?
Solution: You need to put an icon file in the same folder as the extension. And it should automatically be added to the palette. Notice that the filename for the icon should be the same and the extension and that the image types supported are ico, png, bmp, jpg and jpeg. A 32 x 32 image size is acceptable as any other size will be clipped. Keywords: Icon, palette, extension References: None
Problem Statement: Unable to go to simulation environment from oil environment. Error message: Estimating Properties of NBP[1]: Is there any Upper Temperature Limit for TBP Data for assay?
Solution: No there is no limit, till the correlations are valid. You have an option to change the correlation to calculate the properties. Most of the time it resolves the issue. 1. Enter oil environment and Go to the Correlation Tab to add a Correlation. 2. Change the correlation for properties, it is failing. For example if it is failing for critical temperature, change the correlation to TWU critical Property from Leekesler 3. Close the CorrelationSet window and go to the Assay and Correlation Tab. Change the correlation set to the new one. Recalculate the Assay. Complete the same step for Blend. Keywords: Simulation, Simulation environment, environment, leave, basis environment, assay, TBP, Assay, unable, Oil, fail, critical, correlation References: None
Problem Statement: How to add RVP in stream table?
Solution: Double click on the stream table || Add Variable || Calculator || select available RVP correlations || OK. The available RVP correlations are Reid Vapor Pressure Reid VP at 37.8 C API 5B1.1[RVP] API 5B1.2[RVP] ASTM D323/73-79[RVP] ASTM D323-82[RVP] ASTM D4953-91[RVP] ASTM D5191-91[RVP] Aspen API[RVP]. Keywords: RVP, Reid Vapor Pressure, stream table References: None
Problem Statement: The standard methods to register an extension on Windows Vista and Windows 7 don't appear to work. How does one register an extension on these operating system?
Solution: In general, to register an extension, you need to be an administrator on the machine. In Windows Vista and Windows 7, even though you have logged in as an administrator registering an extension may fail (both through the Tools | Preferences menu inside Aspen HYSYS and using the regextn executable). This is because you need to manually select the Run as administrator option for Aspen HYSYS (even if you are an administrator on the machine). To do this, right click on the Aspen HYSYS icon and select Run as administrator, as in the figure below: Once Aspen HYSYS opens, click open the session Preferences to the Extensions tab and register the extension normally. Keywords: register, extension, extn, Vista, Windows7 References: None
Problem Statement: Why am I seeing a Push pin mark instead of Maximize and Minimize buttons on the properties view window?
Solution: In the preferences if you check the Use Modal Property Views this push pin will appear (see below). Once you uncheck the Use Modal Property Views in the preferences the normal window will appear with Maximize and Minimize buttons. Keywords: pushpin, maximize, minimize, property, view, preferences References: None
Problem Statement: New Feature in Aspen HYSYS V7.2 - Compressor and Pump Offsets
Solution: Compressor curve offset calculations An offset term is now available for compressor head and efficiency curves. The offset is applied to the head and to the efficiency calculated from the user-supplied curve coefficients. This allows for a much simpler work flow to adjust head and efficiency to plant data without having to recreate curve calculations in the HYSYS spreadsheets. Pump curve offset calculations An offset term is now available for pump head and efficiency curves. The offset is applied to the head and efficiency calculated from the user supplied curve coefficients. This allows for a much simpler work flow to adjust head and efficiency to plant data without having to recreate curve calculations in the HYSYS spreadsheets. Keywords: compressor, pump, offset, curve References: None
Problem Statement: I am using the DBR Amine property package to simulate an amine tower. I am using an industrial amine, however the results I'm getting from the tower is not consistent with that supplied by the Manufacturer.
Solution: Whenever you choose the DBR Amine package, also select the Li-Mather Model as the thermodynamic model for aqueousSolutions, when the model selection form appears. With the Li-Mather model, the amine package is modified to simulate three phase behaviour by combining k-values from Peng Robinson with k-values from amines VLE & LLE data. As a result, the Li-Mather model shows strong predictability over a wide range of temperatures, pressures, acid gas loadings and amines concentration with blended solvents made up of any two of the six principle amines. This means that you can use any combination of two amines with the Li-Mather model. However, remember that you cannot specify a composition value of zero for either amine (a limitation of the amine package), instead, specify a very small composition value where the composition is zero. An example of industrial amines that this applies to are the Dow CR-301 and Huntsman Jefftreat MS-203, which are both mostly MDEA. Their predicted VLE is not consistent when the Kent-Eisenberg model is used, but show excellent agreement with the Li-Mather model. The results from Li-Mather model are essentially identical to the TSWEET model developed by the Amines Supplier. See Appendix C of the Simulation Basis Manual for more information. Keywords: Amine, DBRamine, Li-Mather References: None
Problem Statement: How can one determine the phase compositions inside the vessel when depressuring a three phase system?
Solution: It shall be noted that for the 3 phase system, the liquid and liquid out stream composition is not representative of vessel liquid inventory. The composition corresponds to what liquid will go out if the liquid valve was open. This corresponds to the liquid out nozzle size and oil / Aqueous interface level. Hence above approach does not give correct results for 3 phase system. To get the correct inventory, the holdup composition variable shall be added to strip chart. This variable is not directly available in strip chart options. It shall be added using drag and drop feature. To access the variable go to depressuring utility sub-flowsheet, open vessel details, in dynamics tab go to holdup, press advanced, go to composition tab. Drag n drop using right click on a strip chart the composition you want. Than use historical data to get the composition. Keywords: composition, left out, remaining, vapor, liquid, blowdown, blow-down, depressuring, depressurization References: None
Problem Statement: For some modeling purposes, it may be desirable to combine several components into a single hypo component. How can one create an average component to represent a group of several components in a HYSYS model?
Solution: For the convenience of this discussion, we will refer to the component representing the group as the hypo average, and the components included in the group as contributing components. The first step is to determine the relative amounts of each components to be lumped. If you have several feeds containing the contributing components, you can use a mixer to combine the feeds into one stream. In the outlet of the mixer, you have the correct relative amounts of the contributing components. This outlet is then fed into a component splitter with two outlets. The contributing components go out in one stream and the rest in the other. The second step is to calculate the component properties of the hypo average. You can get molecular weight directly form the component splitter with only contributing components. To get normal boiling point, you copy the compositions of contributing components to a separate stream with pressure at 14.7 psia and vapor fraction 0. To get density at standard condition, you copy the compositions of contributing components to a separate stream with pressure at 14.7 psia and temperature at 60 F. To get critical properties, attach either a Critical Property utility or Envelope utility to any of the above streams. The third step is to use the properties to create the hypo average component in simulation basis. The fourth step is to copy the total flowrate of contributing components to a new stream with only hypo average. The last step is to mix the hypo average stream with the rest of the components. The implementation is given the attached case file. In this demo case, we will combine three components, hypo 1, hypo 2 and hypo 3 into a single component hypo avg. In the model, stream 1, 2, and 3 are feeds with contributing components. Stream 6 has the correct relative amounts of contributing components, while stream 5 has the rest of the components. Units Bal-1 and Bal-2 copy the compositions of contributing components to separate streams to calculate NBP and density at standard condition. The spreadsheet unit copies temperature, pressure and total flowrate from stream 6 to stream 8. Stream 8 has only hypo avg. Now stream 5 and stream 8 are mixed to present the feed with hypo avg replacing hypo 1, 2, and 3 for downstream flowsheet. Keywords: average, component, combine, lump, group, hypo, hypothetical References: None
Problem Statement: The paper published by Wing Y. Wong PRV sizing for exchanger tube rupture is a well establish guideline in the field to analyze a tube rupture case. In this paper, four scenarios are identified where the fluid in the high pressure side flows through a sharp break to the low pressure side. The scenarios are: · Vapor flowing through break without phase change · Liquid flowing through break without phase change · Liquid flowing through break with phase change · Two-phase (vapor and liquid) flowing through break Is the Pressure Relief Analysis feature in Aspen HYSYS including all these scenarios for tube rupture analysis?
Solution: In V8.6 and below, Aspen HYSYS can only take into account the following scenarios: · Vapor flowing through break without phase change · Liquid flowing through break without phase change · Two-phase (vapor and liquid) flowing through break In V8.8, all scenarios are taken into account, including the liquid flowing through break with phase change. Keywords: Phase change, Tube Rupture, PSV, Scenario References: None
Problem Statement: Is it possible to run different optimization problems within the same simulation case?
Solution: The user can run different optimization problems with the Hyprotech SQP optimizer. This can be done in two different ways: 1) Selecting only the desired optimized variables/ constraints to be included, by ticking the boxes highlighted in the screenshot below. 2) The user can create several separate Derivative analysis, and then select the one to run in the Optimizer. Keywords: Optimizer, Derivative Utility, Hyprotech SQP References: None
Problem Statement: When the tag number of a unit operation or material stream is too long, it is often shown overlapped in the report print out data sheet. How do I show all the characters?
Solution: For example, case G-2.hsc, the tag number for the Pump is P-100 ADR/102-STX00 (Figure 1). The report printout datasheet for heat exchanger, E-101 shows overlapping of the words P-100 ADR/102-STX00 and Pump (Figure 2). To show all the characters for pump P-100 ADR/102-STX007, follow the procedures below: 1.Open the heatexch.rdf file in the Support subfolder, C:\Program Files\AspenTech\Aspen HYSYS 2006.5\Support. 2.Open this file with a notepad. 3.Go to the Design Datablocks Contents. 4.Adjust the size of the block to accommodate more characters, which means we need a bigger size for the block. 5.Go to the block where the fonts are overlapping. In this example, it will be Tube Side inlet. The heatexch.rdf file will appear as shown in Figure 3. 6. Change the size of TextField InletTitle from Size 20 to a bigger number, e.g. 24. 7. Save the heatexch.rdf file. 8. The effect will take place only after removing the current datasheet in the report manager, then re-inserting the datasheet again. Keywords: Report manager, overlapping characters, printout datasheet References: None
Problem Statement: How to separate solids in Dynamics, the solid separation unit Operation (Such as Cyclone and Filters) doesn't work in Dynamics.
Solution: Three phase separator can be used to model solid separation in Dynamics. Refer to the attached HYSYS case files. The files can run in HYSYS 3.2 and later. The attached file demonstrate how separator train can be used to study continuous solid process. In the attached file, the Separator needs two flow spec for the outlet streams. To control the level, level controller is also added. Keywords: Soilid, Dynamics, Separator References: None
Problem Statement: What is the latest version of the Aspen HYSYS-OLGA link extension?
Solution: The latest version of the Aspen HYSYS-OLGA Link extension is V6.2. This is included with the installation of Aspen HYSYS (V7.2-V8.6). This can be seen on the unit operation name as shown below. Keywords: version, OLGA, HYSYS_OLGA References: None
Problem Statement: Is it possible to export the Aspen HYSYS Workbook to Excel?
Solution: Starting with Aspen HYSYS V7.1, the user can export the HYSYS workbook to Excel without using any external utility tools which use OLE linking functionality. All default workbook tabs and any customized workbook tab can be exported directly to Excel. This can be achieved by opening the Workbook and selecting Workbook | Export | To Excel... from the main menu as shown below: Select the workbook page(s) of interest and click Export to Excel. Keywords: Workbook, Excel, HYSYS, Export References: None
Problem Statement: Can Aspen HYSYS model azeotropic systems?
Solution: Aspen HYSYS is able to handle azeotropic systems as long as an appropriate property package is selected. The Equilibrium Plots extension available inSolution 116293 enables the generation of binary and ternary plots, which can be helpful when analyzing azeotropic systems. Keywords: azeotrope, azeotropic, equilibrium, property package References: None
Problem Statement: Triolein, (C17H33COO)3C3H5, is a triglyceride that is frequently used to represent the reactant oil in biodiesel processes. However sometimes the properties like heat capacity, density or enthalpy do not match the ones of the reactant oils such as canola, rapeseed or palm.
Solution: The properties can be modified using the tabular pacakge. The first step is to clone the existing Triolein component in the HYSYS database. FollowSolution document 129729 for guidance on how to do this. After the component has been cloned, go to the Component List. A component is created with the name Triolein*. Next go to the Fluid package window and browse through the 'Tabular' Tab. Activate the 'Enable Tabular Properties' option as seen on the image below: Select 'All properties' from the left hand side window and check the desired properties to change. Notice that if you want to change the Enthalpy or the Heat Capacity, you have to select both the Liquid and Vapor for each property (otherwise the property will not be activated). After the desired properties have been selected, go to the information menu on the left hand side and select the property you want to edit. This will display all the components used in your simulation. Browse to Triolein* and select it. You can type in the coefficients for the equation to calculate the property if you already have them from previously regressed data, or you can click under 'Cmp Prop Detail' to introduce tabular data to obtain an equation to calculate the property. If you decide to do a regression you can introduce your data and the program will calculate the coefficients for you. You can select molar or mass basis and also the desired units. When you are finished entering the data, click on the 'Regress' button. The message on the yellow bar 'PropCurve Ready' means that the curve has been regressed with the data given. Now, the properties will be estimated according to the data introduced. Follow these steps for all the properties of interest. If a more exact representation of the oil is needed, then the rest of the pure component properties need to be reviewed and if necessary modified. Keywords: Enthalpy, Heat capacity, Density, Tabular properties, Triolein References: None
Problem Statement: Are the heating values calculated on dry basis or wet basis?
Solution: The heating values are calculated on a wet basis. Existing water in a stream are included in the heating value calculations. Keywords: Heating value, basis, dry, wet References: None
Problem Statement: I couldn't find start button in adjust operation. Where did it go?
Solution: You will find start button in adjust window, when you will first set up the Adjust operation. You will press it to start it solving but this button will disappear after the first time it solves. Adjust will continue to re-calculate whenever necessary. Keywords: adjust, start References: None
Problem Statement: How to hide and reveal label or name in the PFD?
Solution: The label or name of a stream or unit operation can be hidden or revealed following the steps given below: Select the stream or unit operation. Apply right mouse-click on the object (stream or unit operation). To hide the label, select 'Format Label' followed by 'Hide Label' from the listed options. To reveal a hidden label, select 'Format Label' followed by 'Show Label' from the listed options. Keywords: Hide Label, Reveal Label References: None
Problem Statement: What are the new Process Flow Diagram (PFD) improvements in Aspen HYSYS V7.2?
Solution: The following improvements are made to the Process Flow Diagram (PFD) in Aspen HYSYS V7.2 ? Object types (for example, unit operations or utilities) are now shown in front of object names in view title bars and FlyBy tool tips. ? A switch for Ignore/Restore Unit Op is now part of the object inspection (shortcut) menu for all HYSYS unit operations in the PFD. You can ignore or restore the object without opening its view. Keywords: PFD, enhancement, new, V7.2, improvements References: None
Problem Statement: Data Tables let you monitor key process variables in both steady state and dynamic modes. Variables for all Data Table features are selected in a single location. Variables added to the data tables have the same Unit Set of your model. The problem is that when you copy values from the process data tables into Excel, the variables pasted in Excel will use the default Aspen HYSYS unit set.
Solution: To use the same Unit Set of your model, you have two options: 1) Aspen HYSYS V8.4 includes a button called “Send to Excel” which will send the variable with the same unit set of your model. This button has been included since the release of Aspen HYSYS V8.4. This image shows how the Units Set is conserved. 2) Alternatively, you can use Aspen Simulation Workbook for previous Aspen HYSYS versions. Aspen Simulation Workbook provides easy and robust integration between AspenTech's process simulators and Microsoft Excel, allowing you to deploy models to a wider range of users without writing a single line of code. For more information about Aspen Simulation Workbook, please refer to the links below. Product Overview for Aspen Simulation Workbook http://support.aspentech.com/webteamcgi/SolutionDisplay_view.cgi?key=122083 CBT: Getting Started with Aspen Simulation Workbook in Aspen HYSYS V8 http://support.aspentech.com/webteamcgi/SolutionDisplay_view.cgi?key=138913 Keywords: Data table, Unit set References: None
Problem Statement: A stream cutter is automatically added in the flowsheet when you use two fluid packages in the simulation. However, when the user changes a value in any stream, an inconsistency error appears.
Solution: The user should make sure that the outlet stream of the cutter is not specified. This stream has to be calculated from upstream. Therefore, the user will need to delete all specifications for conditions and composition from the outlet stream. Keywords: stream cutter, over specified References: None
Problem Statement: I am using 'sparse continuation solver' method. When I try to switch to another solving method, Hysys gives me error as below and don't let me change the method. How can I move ahead?
Solution: While using sparse continuation solver, if you want to switch to another method, then you have to press 'clear all' on Parameters|2/3phase page first, to remove 'check' on every tray. After this you will be able to change the solver method without any difficulty Keywords: sparse continuation, Hysim I/O method, switch, two liquid phase. References: None
Problem Statement: Where can I find the Hyprotech SQP optimizer diagnostic file?
Solution: The diagnostic file for the Hyprotech SQP optimizer is created in the working Temp directory: C:\Documents and Settings\Username\Local Settings\Temp This file is named as HyprotechSQP-20091224-100445-454.log where HyprotechSQP is followed by the date in the format yyyymmdd and the time from the computer system clock when the optimizer run is initiated. The diagnostic file contains the tuning parameters and initial values of variables, constraints and objective function. The updated values of the variables in the problem and additional diagnostic information are recorded with each optimizer iteration. Keywords: Hyprotech SQP Optimizer, Diagnostic file References: None
Problem Statement: AspenOne Heat Exchanger Design and Rating program cannot retrieve information from Aspen HYSYS.
Solution: Verify that the Aspen HYSYS Directory path does not have an exclamation (!) mark, otherwise the system will not recognize the folder. Keywords: EDR HYSYS Heat Exchange References: None
Problem Statement: How to enter the ASTM D7096-05 data into HYSYS Oil Manager?
Solution: HYSYS does not have internal conversion method for this ASTM D7096-05 method. According to ASTM documentation, it is a superior method to predict the boiling curve for petroleum products with a final boiling point of 280 C D86 method uses Engler Flask - simple but less accurate. TBP method uses 15-100 distillation trays and more accurate. ASTM D7096-05 method fits more closely to TBP procedure. Thus it is appropriate to take the data as TBP on Vol% to simulate in HYSYS. Supporting notes from ASTM website: ASTM D7096-05 method for determining boiling range of petroleum products: The determination of the boiling range distribution of gasoline by gas chromatographic simulated distillation provides an insight into the composition of the components from which the gasoline has been blended. Knowledge of the boiling range distribution of gasoline blending components is useful for the control of refinery processes and for the blending of finished gasoline. The determination of the boiling range distribution of light hydrocarbon mixtures by gas chromatographic simulated distillation has better precision than the conventional distillation by Test Method D 86. Additionally, this test method provides more accurate and detailed information about the composition of the light ends. The distillation data produced by this test method are similar to that which would be obtained from a cryogenic, true boiling point (15 theoretical plates) distillation. 1.1 This test method covers the determination of the boiling range distribution of gasoline and liquid gasoline blending components. It is applicable to petroleum products and fractions with a final boiling point of 280C (536F) or lower, as measured by this test method. 1.2 This test method is designed to measure the entire boiling range of gasoline and gasoline components with either high or low vapor pressure and is commonly referred to as Simulated Distillation (SimDis) by gas chromatographers. 1.3 This test method has been validated for gasoline containing ethanol. Gasolines containing other oxygenates are not specifically excluded, but they were not used in the development of this test method. 1.4 This test method can estimate the concentration of n-pentane and lighter saturated hydrocarbons in gasoline. 1.5 The values stated in SI units (degrees Celsius) are to be regarded as the standard. Results in degrees Fahrenheit can be obtained by simply substituting Fahrenheit boiling points in the calculation of the boiling point-retention time correlation. Keywords: ASTM D7096-05, D86, TBP, Oil Manager References: None
Problem Statement: Why can't I select a separate fluid package for column models in HYSYS like I can for other unit operation models?
Solution: In most unit operation models, you can select the fluid package for that model from the property view menu for that model. However for column models, specific fluid packages must be assigned differently since columns are generally multi-unit operations that require a subflowsheet. To assign a specific fluid package to a column model, you must first access the simulation basis environment. In the Basis Manager menu, select the Fluid Packages tab. In the top right corner, you'll see a menu allowing you to assign a certain fluid package to each flowsheet associated with the simulation. Simply locate the column subflowsheet of interest and select the desired fluid package. Keywords: Fluid Package, FP, Flowsheet, Subflowsheet, Column, SFS, Sub Flowsheet References: None
Problem Statement: How to export the stream from column environment to main flowsheet i.e. stream connected between a TEE and heat exchanger
Solution: if a stream in the column environment is attached to a tray section or a separator it can be exported to main flowsheet via Flowsheet TAB | Internal Streams | Add and export(more details inSolution 109247). But if the stream is not a boundary stream or not attached column or a separator, then the above procedure is not applicable. The following method is rather complicated but it works. To export any intermediate streams between unit operations in the column enviroment please follow the steps below. 1.First of converge the column with desired specifications. 2. Go to Column Environment and add a balance operation and a new stream. 3. Then using attach mode or by holding Ctrl button connect the source and target streams 4. Then go to property view of balance operation and then select Heat and Mole balance option. 5. Copy the source stream pressure and paste into target stream. 6. Go to the main flowsheet and run the column again to converge. 7. On the column Design TAB | Connections page, under inlet stream define the stream name on main flowsheet. 8. Now the stream is exported to main flowsheet, but it is connected to the column as a feed stream. 9. To use this stream as feed to a rigorous heat exchanger add another balance and define the stream or use Virtual Stream extension to define the copy of this stream. Keywords: internal stream, column environment. References: None
Problem Statement: New Feature in Aspen HYSYS V7.2 - Utilities Enhancements
Solution: Enhancements to the Envelope Utility The new Enable Fixed User Points checkbox on the Performance tab, Table page of the Envelope Utility makes it easier to prepare data for export to Excel or Aspen Simulation Workbook. Once the performance table data is available in Excel, you can plot the phase diagrams; as conditions on the stream change the phase diagrams are automatically updated. Enhancements to the CO2 Freeze Out Utility The CO2 freeze out utility calculations are enhanced to eliminate any unexpected jumps in freeze out temperature due to a very small change in pressure or composition. Enhancements to Depressuring Utility You can now control the CCMB (close component material balance - available on dynamics integrator options) option directly from the utility user interface (applicable for the execution of the utility on). Initialization of the dynamic depressuring utility in Calculate Area mode was incorrect and it has been fixed. When associated to a multi-phase stream, vessel content is now initialized to 50% of liquid. Keywords: Utilities, New V7.2, Envelope, CO2 freeze out, depressuring, utility References: None
Problem Statement: Why can't I see the value of Surface Tension for a mixed liquid phase?
Solution: Aspen HYSYS does not calculate the surface tension for combined two liquid phases. The two liquids could potentially have multiple fluid interfaces. Aspen HYSYS can report the surface tension at one of the vapor/liquid interfaces. Keywords: surface tension, liquid phase References: None
Problem Statement: How does oil manager blend different oils?
Solution: Step -1 Each of the oil in oil manager is calculated and its working curve is generated. We will have following basic information for each assay: Point # Moles Cum. Moles NBP [F] Mole Wt Mass Density [API] Viscosity 1 [cP] Viscosity 2 [cP] User Prop1 [..] User Prop2 [..] At this point the properties curves are calculated such that it meets bulk value supplied by user. Step-2 User creates a blend in oil manager with certain mass/mole/volume ratio of each oils. User also specifies any preference for cut point range. There is a default Auto Cut option available as well. Now the calculation starts. Step-3 Oil manager loops through all the oils in oil manager and finds out the minimum and maximum temperature for hypo components. With cut point option selection, oil manager generates a set of hypo components for different temperature range. Step-4 Each oil composition, MW, density, viscosity and user property curve is now curve fitted to new hypo components boiling range This is the assumption: Composition - blend molar flows MolWt - blends by molefraction of each assay Density - blends by volfraction of each assay Viscosity - blends by massfraction of each assay UserProperty - blends by massfraction of each assay Note: At this stage, we can manually calculate Blend MW and Blend Density. If the user has supplied the bulk values for MW and Density then these values take priority. Step-5 If bulk viscosity is available for each of the oil that is blended then we calculate the bulk viscosity of blend by following formula: Viscblend = Power(Sum(MolFraci*Power(Visci, 1.0/3.0)), 3.0) This is done at two different temperatures and viscosity curve calculated in step-4 is shifted for blend. Step-6 Check for Gravity and MolWt consistency In this step, it is made sure that calculated density and Molwt curve is monotonous in nature. If it is not monotonous then, new density and molwt values are calculated using constant Watson K assumption. Step-7 For each hypo component composition & properties are now calculated using Mid Boiling Point assumption. So far, previous steps calculated using End Boiling Point assumption. Molwt and Density curve is shifted to the bulk values for blend that we have calculated in step-4. Step- 8 For each hypo components now we can calculate critical properties (Tc, Pc, Omega) by using the correlation set that user has supplied. Step-9 We calculate each hypo component ThetaA and ThetaB values for each hypo components by using both the viscosity curves. If bulk value of oils are available then we have calculated the bulk value of blend in step-5. ThetaA and ThetaB are recalculated to match this bulk viscosity. Ofcourse, if user has provided the bulk value of blend viscosity then this takes priority. FAQ: What happens when I have viscosity data entered at non-default temperatures? We recommend user to input the data at default temperatures 37.77 C and 98.89 C. Internally, viscosity curves are calculated at default temperatures. We use linear relationship (log(viscosity) vs. 1/T) correlation to predict the viscosity at other temperature. We utilize this relationship to shift the viscosity curve to get the desired value of viscosity at any temperatures. However, linear relationship may not hold well when the supplied temperature is very far from the default temperatures. Keywords: Blend, steps, oil, assay, Oil Manager References: None
Problem Statement: I want to add an orifice that is not part of the standard API 526 orifices. How do I do that?
Solution: In the Customize tab of the ribbon click on the Custom Orifices button. This will display a window with the standard orifices besides A,B,C,U and W. These are free spaces that you have to add your own orifice. Just check the Add Custom box in the appropriate orifice and it will be customizable space. You can edit the Name and the Area. If you need more spaces to add another custom orifices you can use the standard orifices fields. Keywords: orifice, standard, custom, safety analysis References: None
Problem Statement: How can I define an Assay if my distillation curve contains both Light and heavy Ends, To what extent can I represent the Light Ends with Library components and the Heavy Ends with Hypo-components?
Solution: The best approach depends on the users objective; Depending on the accuracy of the Assay data available, then probably using library component for the light ends is the preferred option, reason being that it is more representative of the defined light components as the correlations implemented in HYSYS for the estimation of the properties of the Hypo-components are largely based on heavier components, which can potentially reduce accuracy than using discrete library components. Overall, the more the data (components) used for characterization, the closer the properties will match and yield reasonable results. Keywords: Light Ends, Assay Characterization, Hypo-components. References: None
Problem Statement: Are Fp and Xt parameters (ISA 75.01) available in a valve?
Solution: ISA 75.01 is implemented in version 2006.5. You can choose either Fisher Universal or ANSI/ISA format in rating page. If you choose a manufacturer (i.e. other than universal gas sizing and simple resistance) you will find this choice in version 2006.5 and up. The picture below shows the interface. Keywords: Fp, Xt, ISA 75.01, valve References: None
Problem Statement: How can I control the mole ratio between component A and B in a stream ?
Solution: You can do this by using a spreadsheet in Aspen HYSYS, as in the attached sample file. In the file, there are 3 components in stream 1, Methane, Ethane and Propane. To control the ratio of the components in stream 1, enter formulas in the spreadsheet. These are the steps: 1. Specify the mole fraction of component Methane in cell B1, 0.4 for example. 2. Enter a formula for component Ethane in cell B2, as a ratio of Methane. Example: Ethane mole fraction = 0.25 * B1 3. Then for the third component Propane, enter a formula: =1-B1-B2. 4. Make sure that all exported values are red (or spreadsheet calculated values), therefore specify in cell C1, = B1 (to allow this value to be exported as component mole fraction of Methane to stream 1) 5. Export values of C1, B2, and B3 (red color values) to the respective components mole fraction. To avoid any link discontinuity, you can use the drag and drop method. Right click on the spreadsheet cell C1, hold the mouse, drag and drop it into stream 1 | composition | mole fractions (Methane). Repeat for other components. 6. After this setup, user has to change the component mole fraction or component ratio of stream 1 in the spreadsheet rather than directly on the stream worksheet| composition page. Please notice that the compositions for all the components must be exported to the stream, even when their composition is zero. Otherwise, the stream won't use the values calculated in the spreadsheet. Keywords: Spreadsheet function, component mole fraction ratio control References: None
Problem Statement: I have added Higher Heating value from property correlation control but it doesn't show same units in spreadsheet as in stream window. Why?
Solution: There can be a few reasons of why don't you see Higher heating value units same in spreadsheet and stream view. 1) If you have added Higher heating value from property correlation control, then it should be added in spreadsheet via Calculator variable. If you add higher heating directly from variable list, then there might be a difference. You can add it using one of the two methods explained below: 1a) On Connection tab of spreadsheet, select add import. Highlight stream of interest =>select variable as Calculator =>add Higher Heating value. 1b) Use drag and drop method: Open stream window, and spreadsheet window at same time (To open two windows at same time, you can open one window and after that open another window from Windows menu at the top). Drag the value using Right mouse click and drop it on the cell in spreadsheet. 2) Another reason can be that, Spreadsheet is using unit set other than your simulation. Spreadsheet is the unit operation in Hysys, which has its own unit set. You can check the unit set used by your simulation and select the same unit set for spreadsheet from its parameters tab, by pulling down unit-set menu. Key words spreadsheet, unit set, higher heating value, HHV Keywords: None References: None
Problem Statement: How do I obtain Std Ideal Liq Vol Flow of selected components in liquid phases via OLE automation?
Solution: There is not a direct way to get Std Ideal Liq Vol Flow of individual and selected components in liquid phases. However, it can be calculated by the following equation based on Hysys Simulation Basis: LiqVolFlow =Total Molar Flow ? MW/( Ideal Density) (1) Ideal density =1/(sum(x/std ideal liquid density) So we can can get the liquid flow flow for each component in your desired phase (light liquid, heavy liquid and combined liquid phase). We also can Std Ideal Liq density from fluid package for each component. For light liquid mass flowrate, we can get as the component flowrate from LightLiqidPhass function, for example: Dim aMassFlowrate As Double Dim aMassFraction As Variant Set hyLightLiqPhase = hyStream.DuplicateFluid aMassFlowrate = hyLightLiqPhase.LightLiquidPhase.MassFlow.GetValue(kg/h) aMassFraction = hyLightLiqPhase.LightLiquidPhase.MassFractions For i = 0 To hyLightLiqPhase.Components.Count - 1 .Offset(17 + i, 0).Value = aMassFlowrate * aMassFraction(i) Next For combined liquid phase, we have to use the back door variable to get the component flowrate, for example, component mass flowrate in combined phase: Set hybd = hyStream For i = 0 To hyOverallFluid.Components.Count - 1 aMonikerName = :CompMassFlow.519.5. & CStr(i) Set hyVar = hybd.BackDoorVariable(aMonikerName).Variable .Offset(28 + i, 0).Value = hyVar.GetValue(lb/hr) .Offset(28 + i, 1).Value = hyVar.GetValue(kg/h) Next You can get the component ideal liquid density as the following: Dim hyCpts As HYSYS.Components Dim hyCpt As HYSYS.Component Set hyCpts = ActiveObject.FluidPackage.Components Counter=0 For Each hyCpt In hyCpts Put the value into our array UserArray(Counter) =hyCpt.StdLiquidDensityValue Counter = Counter + 1 Next 'hyCpt With individual component flowrate, you will be able to compute the std ideal liquid vol flow using Eq. 1. Keywords: Automation, user variable, Macro, Std Ideal Liq Vol Flow, Std Ideal Liq density References: None
Problem Statement: How to get rid of Insensitive message in LNG exchanger?
Solution: The insensitive message in the status bar of a heat exchanger says it could not solve the equation (mass and enthalpy balance and heat transfer eqn with specs such as temp / UA). At one point during the iterations, the error is not changing anymore. To work around this problem, the specs for the heat exchanger can be changed to first solve (converge) the heat exchanger. Then, you can try to solve the heat exchanger using the desired specs, starting from a convergedSolution There are several things you can try to converge an LNG exchanger. 1. Achievable Specs: Please double check your specs and make sure they make sense and achievable. 2. Changing Specs: You could try using a different spec(s). There are several specs available in the specs list. These are (a) Temperature (b) Delta Temp (c) Minimum Approach (d) UA (e) LMTD (f) Duty (g) Duty Ratio (h) Flow (i) Flow Ratio (j) Subcooling (k) Superheating etc. 3. Recycle Block: If you have a feed to the LNG that is not user specified (calculated by HYSYS) and the stream is part of a loop, adding a recycle block in it may help to converge the LNG exchanger. 4. Minimize number of LNG: If you have several LNG heat exchangers in series, please try to reduce / minimize the number of exchangers. Keywords: LNG exchanger, Insensitive, HYSYS, Specs References: None
Problem Statement: How to set Aspen Properties or COMThermo as the Default Basis in Aspen HYSYS
Solution: By default, when you add a new component list or property package in Aspen HYSYS V7.0 or later, it will set the default component list and property package as HYSYS. But to if you would like to set Aspen properties as Default Component list and Aspen Properties as Default fluid package then 1. Go to Tools | Preferences | Property System 2. Select the Aspen Properties as Default property system from the drop down menu. 3. Close the view. Now Aspen HYSYS uses Aspen properties as default property system. Keywords: Aspen Properties, Components, Fluid Package, Basis, default. References: None
Problem Statement: How can I link a Shell & Tube (TASC+) thermosiphon heat exchanger model inside an Aspen HYSYS Column subflowsheet?
Solution: ThisSolution assumes that you already have a thermosiphon reboiler model in Shell & Tube (TASC+) or that you know how to create one. If you are starting a distillation column from scratch follow the following procedure, otherwise if you already have a distillation column replace the reboiler with a heat exchanger (more details onSolution 115038) and continue from step 6. 1. Place a distillation column or a reboiled absorber in your flowsheet. 2. Make sure you have enabled the input experts (Tick Use Input Experts in Menu Tools | Preferences| Simulation | Options page). 3. Enter the data in the Column Connections page as necessary and click Next 4. In the Reboiler configuration page select the baffle configuration you want for the column bottoms and from the Reboiler type selection choose a heat exchanger. Select shell side as the hot side location since in thermosiphons the steam feed is located on the shell side. Complete entering all the column input forms as required. 5. If you selected a baffle in the bottoms you will need to add an extra specification, usually set as a split ratio. 6. Once the column is converged add a new specification Draw rate and as a steam select the feed to the reboiler (enter the Column environment to see the name if you are not sure). 7. In case you have configured a baffled bottom circulation deactivate the specification on the bottom split and activate the reboiler flow rate spec. Otherwise set the reboiler flow rate spec as an estimate only. 8. Run the column. 9. Enter the subflowsheet and import the Shell & Tube file. (make sure the reboiler file is saved in simulation or rating mode before importing) 10. Set the thermosiphon Circuit Calculation to Fixed Flow (EDR-Shell & Tube | Application page | Thermosiphon). 11. Now the column is overspecified, since the reboiler duty will be computed based on the reboiler inlets, you need to remove one specification and run the column When you link the EDR reboiler inside a Hysys column it adds two degrees of freedom. One is the reboiler heat duty, which is calculated by EDR (not modifiable) and the other is the reboiler flow or the split flow. If you have a baffled Column bottom it is recommended to specify the reboiler flow rate, this way the Bottom split will be modified to match that. If you set as an active specification the bottom split rate the column may fail to converge. Otherwise if you don't have a baffled column bottom you need to set the reboiler flow rate specification as an estimate only. The flow rate will be computed directly based on the height of liquid inside the column and the pressure at the liquid surface. Note that if you have convergence problems you can try to increase the reboiler heat balance error tolerance. Keywords: Heat Exchanger, Boiler, TASC+, HTFS+, Exchanger Design and Rating, Modified Hysim I/O References: None
Problem Statement: Which .NET framework is needed for writing an .NET based extension
Solution: All HYSYS v8.XX have 4.0 NET framework. If user is creating a NET based extension, he will have to specify 4.0 framework in his project. To do that, 1. Open the properties of the project. On the Compile page, click bottom Advanced Compile Options... 2. Choose the framework from Target framework (all configuration): Keywords: Extension References: None
Problem Statement: I'm working with a plot in Aspen HYSYS and want to manipulate the display units for the data, independent of the simulation unit set.
Solution: While looking at the plot view, simply right-click in the background of the plot and select Graph Control. In the Graph Control menu, select the Axes tab. For each listed variable on the left side of the menu, you can select/de-select the Use Default Units check box. To use the default simulation unit set, check the box. If you wish to select your own, de-select the box and choose your desired units. Keywords: Graph, Plot, UOM, Units, Display References: None
Problem Statement: Why is the liquid which is coming out of a valve, a higher temperature than the liquid in the inlet? Some gases can have negative Joule-Thomson effect. Why a liquid stream is showing this behavior?
Solution: Negative Joule-Thomson effect is rather common for liquids. The Joule-Thomson coefficient is typically negative for liquids at temperatures well below their critical temperature. That means, in general, we should observe a temperature rise across a valve if the fluid is liquid. Keywords: liquid, J-T, Joule-Thomson, temperature rise, valve References: None
Problem Statement: When creating a new correlation set, the Save correlation set to file option is selected. But when loading the saved set, the program shows that the file was not created:
Solution: This problem is solved by modifying the Stream Correlation Sets File path. Click on the Tools menu and the Preferences submenu. The Session Preferences window is now open. On the Files tab, select the Locations page and scroll down to select the Stream Correlation Sets File path. The default is 'Support\StreamCorrSet.xml' as shown below: Change the path to 'Support' as presented in the following figure: Keywords: Stream Correlation Set References: None
Problem Statement: How to model Divided wall column in Aspen HYSYS?
Solution: There are different ways to model Divided wall columns in Aspen HYSYS. An informal presentation about modeling DWCs and a sample simulation case with 2 conventional columns and the equivalent DWC is attached alongwith. Keywords: divided wall column References: None
Problem Statement: Why does Aspen HYSYS give different compressor outlet temperature from GPSA method?
Solution: There were number of queries from the users who compared the compressor outlet temperature applying the GPSA method using the isentropic exponent, k. Note that the GPSA method estimates the temperature difference assuming ideal gas behavior, k = Cp/(Cp-R), not the rigorous k, (k=Cp/Cv) as available in Aspen HYSYS. As a result the temperature calculated from the GPSA method can be significantly different from Aspen HYSYS in particular when a high compression ratio is used in the simulation. The method used within Aspen HYSYS for compressor calculations has been described in the knowledge baseSolution ID 109454 and further details are available in Aspen HYSYS Unit Operation Guide, AspenHYSYSV7_1-UnitOps.pdf. Keywords: GPSA, Compressor References: None
Problem Statement: How to report the total liquid holdup for a pipe segment in Aspen HYSYS
Solution: The total liquid holdup is not reported in the Aspen HYSYS pipe segment but can be calculated manually using the Aspen HYSYS spreadsheet. The liquid fraction for each segment is imported into the Spreadsheet, each individual segment volume is calculated by multiplying the segment length by the total pipe area, finally the individual segment hold up is multiplied by the segment volume and summed up to give Total Liquid Holdup for the pipe. The file attached illustrates this work process. The pipe segment volume fraction is linked to the spreadsheet and so will update with any changes in the pipe holdup. Keywords: Pipe hold-up volume, Total liquid hold-up, Pipe liquid fraction References: None
Problem Statement: How do I create Datablock for user defined unit operations?
Solution: Refer to the attached documentation. You need to create a rdf file with the same name as the extension's edf file. For example if you have created an extension Saturate Extension, you would need to create a saturate.rdf file and place it in the same directory as the saturate.edf file. The RDF file needs to me modified for format, monikers and edf file name for extension. The documentation attached along with the sample file of rdf available in C:\Program Files\AspenTech\Aspen HYSYS 2006\Support can be used to study the control. The moniker can be known by running the script manager Tools | Script manager. Note: EDF and RDF, both files can be edited in note pad. Keywords: Datablock(s), Datablock, Extension, Print References: None
Problem Statement: Why does the cut point in the Stream Property Spec result in a different temperature than predicted by the Boiling Point Curves utility?
Solution: Within the HYSYS column specifications for crude columns there are three cut point specifications available. 1. Column Cut Point 2. Column Stream Property Spec | Cut Point 3. End Point Based Column Cut Point These can be seen from Monitor | Add Spec or Specs | Add pages of the column property view. The Column Cut Point Specification and the Boiling Point Curves utility result in same calculated cut point temperature as they are based on correlations defined in the HYSYS Oil Manager. The Column Stream Property Spec | Cut Point and End Point Based Column Cut Point result in same cut point temperature as these are based on the correlations defined in RefSYS. Thus cross comparison of cut points between above methods results in slightly different cut point temperatures. If the crude is characterized using HYSYS Oil Manager, then use Column Cut Point specification in the column and to verify the results, use the Boiling Point Curves utility. If the crude is characterized by the RefSYS Assay Manager, then use the Column Stream Property Spec | Cut Point or End Point Based Column Cut Point specification in the column and to cross check the cut point temperature use the Petroleum Assay Utility. Keywords: Cut Point, Column Cut Point, Assay, Boiling Point Curves Utility, Petroleum Assay Utility, RefSYS, Oil Manager. References: None
Problem Statement: For simulations containing many Unit Operations, it can be very tedious for the next engineer trying to find the input specifications for certain Unit ops. Is there a way in Aspen HYSYS to allow users to access certain object inputs without having to search individual object in the PFD?
Solution: The Flowsheet Summary can be used to view the user input values. Select Flowsheet | Flowsheet Summary from the main menu. The Flowsheet Summary will categorize the objects to allow easy access of any streams or unit ops in your PFD. 1. Navigator page will allow you to navigate through individual object without having to search and double click on it in the PFD. 2. Input summary will show you only user inputs in the object selected. Keywords: Flowsheet summary, Hysys inputs References: None
Problem Statement: What does FittingNo in the Pipe Segment (sizing page) represent? Is this the number of specific units that one would like to include in that segment (e.g. a bend)?
Solution: The 'FittingNo' is the quantity of a particular fitting that will be modeled by a particular segment. 'Fitting No' (which becomes an active spec when choosing a fitting) was introduced in the HYSYS Pipe Segment since V7.0 to model multiple (similar) fittings at one go. When this number is greater than one, the pressure drop calculation for the segment will assume that there are several fittings right in a row at that location. Therefore, when using this approximation, the calculation does not take into account the exact location of the fitting in the pipeline. For example, if you have 10 bends in your pipeline, rather than inserting 10 separate segments to represent each bend at a given location, one segment can be used to model all 10 bends. Under certain conditions, this approximation will not lose much accuracy in the pressure calculation. Keywords: FittingNo, Pipe Segment References: None
Problem Statement: What is the equivalent method for ASTM D7213
Solution: According to American Society for Testing and Materials (ASTM) the boiling range distributions obtained by ASTM D7213 test methods are theoretically equivalent to those obtained by true boiling point (TBP) distillation. They are not equivalent to results from low efficiency distillation such as those obtained with Test Method D 86 or D 1160. So in HYSYS when you are modelling the ASTM D7213 assay you have to choose TBP as Assay data Type Please take a look at the following reference for details. http://www.astm.org/Standards/D7213.htm Keywords: ASTM D7213, TBP, assay, ASTM References: None
Problem Statement: What are differences between first tray in section and first tray in column in the section property mode in tray sizing utility?
Solution: In the HYSYS tray utility there is an item on the Design tab, Specs option called Section Property Mode. The HYSYS Unit-Ops guide explains that: The Section Property Mode drop-down list enables you to select the start tray for the Property Mode calculations. HYSYS provides two selections: ? The First Tray in Section option applies to a column with multiple sections and each section has different Property Mode calculations. The First Tray in Column option applies to a column with single or multiple sections and only one type of Property Mode calculation is applied to the whole column. First tray in column option takes the physical properties (density, viscosity etc) from the first tray of the column. For example, for flooding calculation of tray number 25, HYSYS will use the density viscosity etc taken from the tray number 1. First tray in section takes the properties from first tray in the section. If a section consists of tray 24 to 30, then for flooding calculation in tray 25, properties will be taken from tray 24. So, first tray in section will give more accurate result. At first, tray sizing utility came out for sizing only. In this case it uses properties from the first tray to come up with a design. When rating came into the utility, first tray option made into rating mode as well. To make improvement, first tray in section was introduced. Conclusion: First tray in section is more accurate. For better results, divide a column into different sections. Keywords: property, mode, tray sizing, References: None
Problem Statement: Why the size of the separator is not changed no matter what I change for the demister, thickness and demister to top.
Solution: The separator sizing utility is only accounting for separation based on the Souders-Brown equations. It simply uses the densities to find a maximum vapor velocity and then the vapor flowrate to find the area. This leads to the diameter used in the utility. The other parameters are calculated by subtraction, calculations of surge heights, and a general guidance of values; such as the 1/4 * D or 1/2 * D terms in the length equations below. So, it is not accounting for any secondary separation. The total length is calculated using one of two equations depending on the specifications. In most situations these two equations should lead to the same length calculation. Length = Diameter*L/D + 1/2*Diameter. -or- Length = 1/4*Diameter + Demister Thickness + Inlet Nozzle To Demister + Sump To Inlet Nozzle + Demister To Top + Liq Surge Height. When surge heights and demister properties are specified the second equation is used to calculate length, diameter, and other parameters which aren't specified. When L/D and other similar parameters are specified the first equation is used and then the demister properties are found from there. Keywords: Separator size References: None
Problem Statement: How do I delete a pipe segment without deleting all the following segments?
Solution: User tries to delete a pipe segment in between several other segments and when click Delete Segment all the following segments are also deleted. If you only want to delete a column in your pipe segment editor, you have to highlight the number of the segment as shown below. On the other hand, if you want to delete all appended segments after the one you want to keep. Then click in the cell above the number of segment as shown below. Keywords: Pipe Segment, Delete Segment References: None
Problem Statement: When you try to simulate a Component Splitter there are three ways to define your equipment: Feed Fraction to Products, Fraction in Products and Flow in products. What are the differences between these three definitions?
Solution: An example: Let?s suppose that we have a Feed stream with 5 components: X1F F = F1 Component 1 X2F F = F2 Component 2 X3F F = F3 Component 3 X4F F = F4 Component 4 X5F F = F5 Component 5 F Feed And in the splitter you have: In order to specify the equipment, you need to add the split per component: 1. Feed Fraction to products: You can define the feed flow fraction that you want in the overhead or bottoms stream. 2. Fraction in Products: You can define the component fraction in the overhead or the bottoms stream. 3. Flow in products: You can define the component flow in Overhead or bottoms. Keywords: Splitter, components, fractions. References: None
Problem Statement: How to simulate the valve percent open position with time?
Solution: You need to make modification on valve actuator position. A. Select radio button Linear on valve property interface (Dynamics ll Actuator) B. The rate at which valve can open or close is defined in the row “Actuator Linear Rate [%/second]”. So if you put 5 here, it would mean that valve will open 5 % every second. So in 20 second, it will open 100%. C. Also, you need to enter the actuator desired position. So if valve is closed and your desired position is 100%, the valve will open till 100% with the rate you defined in B above. Keywords: Stroke, Valve, Open, Percent, Output References: None
Problem Statement: Can the hydrate utility be used on mixtures containing high concentration of CO2?
Solution: In the attached document, you will find two validation cases of hydrate utility applied to mixtures with high concentration of CO2 (~90 mol%) and small amount of methane (~5 mol%). The results show that HYSYS hydrate utility is adequate for these mixtures. Keywords: CO2, hydrate utility References: None
Problem Statement: Is it possible to recover the original inlet component lumped when the Aspen HYSYS oil characterization method is selected using the delumper?
Solution: When the HYSYS Oil Characterization method is used in lumping, the generated hypothetical components do not have the knowledge on the distribution of the inlet components. Therefore, if the inlet components are first lumped using this method, the delumping process will not recover the original inlet components, except the ones kept in the lumper's outlet component list Keywords: HYSYS Upstream, Delumper, Components References: None
Problem Statement: What phase does the surface tension reference in the column Performance | Plots tab?
Solution: For a Vapor-Liquid column, the surface tension corresponds to liquid phase interface. In a Liquid-Liquid column, the surface tension corresponds to the aqueous phase. Keywords: surface tension, column, profile, performance References: None
Problem Statement: How does one effectively use the Load Workspace and Save Workspace features in Aspen HYSYS?
Solution: There are two ways to use the Load Workspace feature. Use Load Workspace to switch between different cases opened within the same instance of Aspen HYSYS Suppose you have two open cases (tutor.hsc & P-1.hsc). At any given time you can view only one case or file. The Load Workspace feature can be used to switch between the two, as described below: Select Windows | Load Workspace. 2. Use Load Workspace to switch between Aspen HYSYS layouts The Workspace is a specific organization of property views for the current case. Suppose you have opened several property views such as the PFD and Workbook as well as certain Controller Face Plates and Strip Charts that you have arranged in a convenient way for viewing. You can save this arrangement as a workspace and recall it at anytime. This can be particularly useful when running dynamic cases. Workspace layout to be saved: 1. Select Window | Save Workspace. The Save Workspace property view appears. 2. In the Save Workspace As field, enter the name of the workspace (i.e. P1 demo2). 3. Click Save. 4. Close all the forms. 5. Select Window | Load Workspace. The Load Workspace property view appears. 6. In the list of available cases, select the case in which you are currently working. 7. From the list of Available Workspaces, select the workspace you want to use (i.e. P1 demo2) 8. Click Load. You will be able to switch between the different views/workspaces. Attached is the HSC file used in the screen captures. Keywords: workspace, load, save, property view References: None
Problem Statement: Do not see the EDR - Shell & Tube option in Aspen HYSYS Heat Exchanger Model under Design Tab | Parameters page
Solution: This issue can be fixed by performing the Version Fix for Exchanger Design and Rating (EDR) Program. For the following, user need Administrative Privileges. 1. From Windows Start menu, Go to Programs | AspenTech | Exchanger Design and Rating V7.1 (latest version of EDR program) | Version Control Utility. 2. Select the version V7.1 (or same as HYSYS version) of Exchanger Design and Rating (EDR) Program and click Fix. 3. After the version registration is completed, make sure the Check mark is against the desired version. 4. Exit the version control utility. 5.Open HYSYS and go to Heat Exchanger and verify the EDR-Shell&Tube option is available under Design Tab | Parameters page. Keywords: EDR, Heat Exchanger, Model, EDR-Shell&Tube, Shell&Tube References: None
Problem Statement: To observe the behavior of a compressor with performance curves, a plot of inlet flowrate vs outlet pressure can be useful. In many cases, a user would like to plot volume flowrate at the inlet vs outlet pressure. Since volume gas flow is not a specified stream parameters, we present scheme to generate the plot.
Solution: First, we need a scheme to adjust a specified flowrate (molar flow or mass flow) for a given volume flowrate. This can be achieved through an Adjust unit. The Adjust unit modifies the molar flowrate until the calculated volume flowrate calculated for the stream is within the tolerance to the user-specified value. Second, we need to derive a mechanism to vary the specified volume flowrate over a range. We can introduce another level of indirection, i.e., spreadsheet. In a Spreadsheet unit we specify a cell to hold the current value of volume flowrate. This value can be varied systemically from Case Studies in Databook over a given range and step size. In the attached case file, the above schemes are implemented. Keywords: volume flowrate, case studies, compressor References: None
Problem Statement: What is the easiest way to display Hydrate Formation Utility results in workbook?
Solution: Please open any example Aspen HYSYS case from below sample folder C:\Program Files\AspenTech\Aspen HYSYS V7.X\Samples Procedure: 1. Open Tutor1.hsc 2. Tools/Utilities/Add Hydrate Formation Utility/ Select stream as Feed1 & please specify name as Feed1 under performance one can able to see the results 3. Please click on workbook icon 4. On Toolbar/Workbook/Set Up 5. Click on Add then select Hydrate Formation Utility from + Utility Objects then click on OK * If the user want to display workbook results for above utility on PFD then right click on PFD/Add Workbook Table/Select Hydrate Formation Utility Note: By default, the user can see Hydrate formation temperature and Hydrate formation pressure results. If the user wants to add another variable, for example whether hydrate forms in stream, they can go back to Workbook / Setup / Variable / Add / From Variables and add whether hydrate forms in stream ( which is the last variable in the list) then click on OK. Keywords: Hydrate formation utility results in workbook, hydrate formation status, hydrate results on PFD References: None
Problem Statement: After simulating a model using both the PIPESYS extension and the pipe segment, the final temperature, pressure and heat loss matched rather closely. However, when I checked the overall HTC, the difference between these two methods is considerable. How can this be?
Solution: The difference between the Overall HTC reported in the PIPESYS extension and in the pipe segment is due to the diameter that they are related to. In other words, the overall HTC reported in the pipe segment is based on the outside diameter of the tube, while the one reported in PIPESYS is based on the outside diameter including the coating width. Note this is only a convention to specify which area should be used in the heat transfer calculations and should not affect the final result. To illustrate this, refer to the example file attached. In this case : Outside diameter of the tube (OD)=219.1mm Coating Width=50.8mm Outside diameter with coating (ODC)=320.7mm Q=U(Pipesys)*ODC*pi*dL*DT=U(segment)*OD*pi*dL*DT U(segment)/U(Pipesys)=ODC/OD=320.7/219.1[mm]=1.472/1.0129[KJ/h*m2*C]=1.46 Keywords: heat transfer coefficient, reference diameter References: None