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Problem Statement: Since aspenONE Process Explorer stores comments and annotations into the Aspen InfoPlus.21 database, does this mean that Aspen SQLplus can be used to programmatically. | Solution: Yes. Comments can be inserted through Aspen SQL PLus using a query into the history repeat area of the record Comments, which is defined by IP_CommentDef. The following is a sample query to insert a comment using an SQLplus query:
insert into Comments (IP_CMT_TIME, IP_CMT_SUBMITTER, IP_CMT_QLEVEL, IP_CMT_TEXT, IP_CMT_EVENT_TYPE, IP_CMT_URGENCY, IP_CMT_REF_DS, IP_CMT_REF_TAG,IP_PLANT_AREA, IP_CMT_RANGE) values ('10:00:00', 'CORP\CHENAA', 'Good','This is a new comment','Comment','Observation','CHENAVM','ATCP301','R2','10:00:00')
Keywords: Insert comments programmatically
References: None |
Problem Statement: Why is there a temperature discrepancy when flashing the streams leaving a rate-based distillation column?
If you add an adiabatic heat exchanger to an outlet stream, the temperature and vapor fraction changes. | Solution: For a rate-based stage, the vapor and liquid are NOT in equilibrium. Vapor-liquid equilibrium is only assumed at the interface, so is the chemical equilibrium. Therefore it is normal to get a different temperature if you flash the stream from a rate-based stage. An outlet stream from a rate-based stage is not an equilibrium stage. Neither vapor-liquid equilibrium nor chemical equilibrium is achieved for the outlet stream.
Keywords: None
References: : CQ00357921
Key Words
RateSep |
Problem Statement: What is the difference between Murphree and vaporization efficiencies and how should they be used? | Solution: Murphree Efficiency is described as:
Meff(ij) = [ Y(ij) - Y(ij+1) ] / [ (Kij * Xij) - Y(ij+1) ]
Vaporization Efficiency is described as:
Veff(ij) = Y(ij) / [ K(ij) * X(ij) ]
Overall Efficiency is described as:
Oeff = Neq / Nact
Where :
Meff = murphree efficiency
Veff = vaporization efficiency
Oeff = overall efficiency
K = equilibrium K value
X = liquid mole fraction
Y = vapor mole fraction
Neq = number of equilibrium stages
Nact = number of actual stages
i = component index
j = stage index
The difference in efficiencies is that the Murphree efficiency takes into account the adjacent stages while the Vaporization efficiency is limited to the stage in question only. The Murphree efficiency and Vaporization efficiency are meant to be used for those components in the system that are more mass transfer limited than the rest. The efficiencies are therefore used to account for components' deviation from equilibrium.
The Murphree and Vaporization efficiencies should not be confused with the overall efficiencies. In order to meet your overall efficiency you must adjust the number of stages you input in the Radfrac.Main form.
When to use the stage versus the component efficiencies?
Use the stage efficiencies only when you know for a fact that there is a section in your column that has a different overall efficiency from the rest of the column. This is due to the tray type or packing used. It also happens when trays are dirty so there isn't good contact.
Keywords: radfrac
efficiency
References: None |
Problem Statement: This knowledge base article describes what is allowed with respect to deletion and modification of historical data in the Aspen InfoPlus.21 database. | Solution: Standard Aspen InfoPlus.21 data records will allow a user to modify existing data values in history. This can be done through an Aspen SQLplus query such as:
Update atcai set ip_trend_value = '100.0' where ip_trend_time between '18-jan-06 16:00:00' and '18-jan-06 16:30:00';
The results of this query on the existing values for this record in the historian are shown below. When a data value in history is changed the corresponding IP_TREND_QLEVEL field will have /M appended to it to indicate that this value has been modified. This is desirable because, if incorrect data is accidentally written to history, the system administrator has the ability to correct the errors.
The only restriction is that a time stamp cannot be changed or deleted once it has been written to history. This means that once a value is stored in history, the value can be changed, but the individual historical occurrence can never be deleted.
Keywords: timestamp
change
alter
modify
delete
erase
Good/M
IP_TREND_QLEVEL
References: None |
Problem Statement: What is the maximum length of the tag name in the Test API? | Solution: Through Cim-IO Core version 2004, the maximum allowable length for tag names in the Test API (cimio_t_api.exe) was 80 characters. In version 2004.1 and above, the maximum allowable length for tag names is 255 characters.
Keywords: test
api
character
name
length
References: None |
Problem Statement: In the Activated Economic Analysis dashboard, the default currency units are displayed in USD(US Dollars). If the user is trying to change this wihtin an Economic Analysis template while Economic Analysis is Active, Aspen Plus will still show the units in USD. This can be demonstrated even if the analysis is deactivated and re-activated again. How can the units be changed to another currency such as GBP(Great British Pound, EUR( Euro) or others? | Solution: The user can find the option to modify the currency units and location for an economic analysis under the 'Economics' tab>'Cost Options'(shown below) (or in the Simulation Environment under Setup>Costing Options folder>Costing Options Sheet).
Then to use the template with other currency units, the can carry out the following steps below:
1. Remove default template (US_IP) using Delete Scenario button
2. Click Browse button in Setup| Costing option folder| Costing option sheet and select scenario template from Templates directory (C:\ProgramData\AspenTech\Economic Evaluation V8.x\EE_Templates\Templates) or the template which one created.
3. Activate Economic Analysis using Economic Analysis button from Analysis Dashboard
4. Then all results in Aspen Plus will show the selected currency units:
The user can also change units before using the Activated Economic Tool by following steps 2 through to 4.
Keywords: Currency Units, Activated Economic Analysis
References: None |
Problem Statement: KB Article 103797 shows how to add large groups of records to folders using SQLPlus. In addition, it might also be useful to use a query to create folders | Solution: The following SQLPlus query reads folder names and description and tag names from a text file. Then it creates folders (FolderDef records) and inserts the specified tags.
Prerequisites:
Tags must exist or be created beforehand
The input file must be in the right format: folder_name, tag_name, folder_description
You will need to save the following query line as InsertFolder under a QueryDef record:
INSERT INTO &1 (record_name) values ( '&2' );
Note: this sample query is for testing purposes only. Please revise it before running. Also it does not do any error checking.
LOCAL myLine CHAR(132);
LOCAL myFold CHAR(80);
LOCAL myName CHAR(80);
LOCAL myDesc CHAR(80);
-- Step through each line in the file
SET Expand_Repeat 1;
FOR (SELECT LINE AS myLine FROM 'C:\temp\tags.txt') DO
myName = SUBSTRING(2 OF myLine BETWEEN ',');
-- Check if folder exists and create if necessary
myFold = SUBSTRING(1 OF myLine BETWEEN ',');
IF myFold NOT IN (SELECT name FROM FolderDef WHERE name = myFold) THEN
WRITE '*** Creating new folder: ' || myFold;
INSERT INTO FolderDef (name, folder_parent) VALUES (myFold, 'Folders');
ELSE
WRITE '*** Folder: ' || myFold || ' already exists';
END
myDesc = SUBSTRING(3 OF myLine BETWEEN ',');
START RECORD 'InsertFolder', myFold, myName;
WRITE '*** Tag: ' || myName || ' created and put into the folder: ' || myFold;
END
--END
Keywords: SQLPlus code
Folders
Add
Create
References: None |
Problem Statement: The sqlplusx utility doesn't allow parameters to be passed in the same way as iq.exe does. If you type sqlplusx /? it lists the correct parameters.
D:\Program Files\Aspentech\InfoPlus.21\db21\code>sqlplusx /? Usage:
sqlplusx [/h=hostname] [/p=port] [/t=timeout] [SQL command]
Executes an SQLplus command on a remote node.
If /h is not specified, the SQLplus default host from sqlplus.ini is used. If /h is specified but /p is not specified, then port 10014 is used If /t is not specified, the execution timeout is 30 seconds. SQL command should be enclosed in double quotes.
If SQL command is not specified, the command is read from the standard input The standard input can be redirected from a file.
Example:
sqlplusx select name from definitiondef
sqlplusx /h=myhost select name from definitiondef
sqlplusx < t.sql
sqlplusx only uses the standard input for the query if no command is specified on the command line. sqlplusx < query.sql fred is actually executing the command fred. | Solution: You can use sqlplusx to execute a SQLPlus start command to run a query that is stored on the InfoPlus.21 server and then pass parameters via the start command.
Sample: sqlplusx /h=yelm start 'c:\users\default\t.sql','fred'
In this sample the script t.sql is on the server yelm. The start command passes fred as the first parameter.
Keywords: SQLPlus
References: None |
Problem Statement: Even though the license points used can be obtained from the Record Utilization tab accessed from the Aspen InfoPlus.21 Administrator, it does not provide a breakdown into details such as licensed points used by individual definition family. | Solution: 1. Total licensed points used.
In Aspen SQLplus v2004.2, new license functions are introduced. To get the total licensed points used, simply execute the following SQL query.
WRITE GETPOINTCOUNT;
For earlier version, execute the following SQL query.
SELECT count(*) AS Total Licensed Points Used FROM ALL_RECORDS
WHERE DEFINITION IN
(SELECT DISTINCT name FROM DefinitionDef.1 WHERE history_field_pntr <> 0);
2. Total licensed points used by individual definition family.
SELECT DEFINITION AS Definition Family, count(*) AS Total Licensed Points Used FROM ALL_RECORDS
WHERE DEFINITION IN
(SELECT DISTINCT name FROM DefinitionDef.1 WHERE history_field_pntr <> 0)
GROUP BY DEFINITION;
3. Listing of all records which consume licensed points and the definition family they belong to.
SELECT name AS Record Name, DEFINITION AS Definition Family FROM ALL_RECORDS
WHERE DEFINITION IN
(SELECT DISTINCT name FROM DefinitionDef.1 WHERE history_field_pntr <> 0)
ORDER BY name;
Keywords: license points
utilization
definition
definition record
definition family
definitiondef
References: None |
Problem Statement: How to modify the Maximum number of rows for SQLPlus Web service in Aspen InfoPlus-21? | Solution: 1- Configure 32-bit ODBC
a) Open ODBC Data Source Administrator(for 64-bit system, you can open it from C:\Windows\SysWOW64\odbcad32.exe)
b) Â Go to System DSN tab
c) Click on add and select AspenTech SQLplus
d) Fill in ODBC Data Source Name and select Aspen Data Source(in this example, ip21 is the ODBC data source name)
2- Modify Web.config for SQLplus Web Service
a) Go to C:\inetpub\wwwroot\AspenTech\SQLplusWebService
b) Modify Web.config
Replace
<add key=ConnectionString value=DRIVER={AspenTech SQLplus};HOST=localhost/>
With
<add key=ConnectionString value=Dsn=ip21/>
c) Restart IIS
3- Change Maximum Rows to 10 (default value is 10,000)
a) You can change it from ODBC Advanced setting
b) Change it in Registry:Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\ODBC\ODBC.INI\ip21
4- Verify if it works.
a) Browser to http://localhost/SQLplusWebService/SQLplusWebService.asmx?op=ExecuteSQL
b) Write a simple query and click on invoke
Only 10 names have been returned.
Keywords: SQLPlus
Web Service
Maximum
WebService
References: None |
Problem Statement: How to fix the error: Unable to acquire AEA_PIMS license | Solution: The fix described in thisSolution applies ONLY to a server that has network license. This error can be fixed by
a) restarting the SLM server and
b) restarting the Aspen Base Load service
T0 restart the SLM server
1) Go to C:\Program Files (x86)\Common Files\SafeNet Sentinel\Sentinel RMS License Manager\WinNT
2) Double click on loadls.exe and select Remove
3) Double click on loadls.exe again and now select Add
To restart Aspen Base Load service
1) Go to Start and Click on RUN, then type in: services.msc
2) In the services dialog, right click on the Aspen Base Load Service and select Restart
Keywords: Unable to acquire PIMS license
AEA_PIMS
Base load service
Restart SLM server
References: None |
Problem Statement: Why can't Fill Background button be unchecked in Aspen Process Explorer Graphics data field? | Solution: The Fill Background button in an Aspen Process Explorer graphic data field is grayed out and cannot be unchecked. This feature caused a problem with tags that refresh frequently with partially redrawn backgrounds so it was disabled. It still works for Text fields and that's why it was not removed from the application.
Keywords: Fill background, Process Explorer Graphic Editor, data field, check box
References: None |
Problem Statement: How do I check the CRDBLEND structure created by Aspen PIMS internally? | Solution: Consider this CRDBLEND example, where we use crudes ARL and AHV to make a new blended crude MX1:
The crude blend structure can be seen in the internal crude unit structure that PIMS builds, based on entries in the CRDDISTL, CRDCUTS, CRDBLEND and Assay tables. We can see this structure in the data validation report.
For example if your blended crude MX1 is used in crude unit 2 (CD2), then in table PRNTTABS we need the following entry:
*Â TABLE
PRNTABS
Table of Contents
*
Miscellaneous Tables to be Reported
TEXT
***
*
BOUNDS
User Defined Bounds
PGUESS
Initial PGUESS
PDIST
Initial PDIST
PCALC
Property Calcs
ZASSCD1
CDU1, Mode 1
ZASSCD2
CDU2, Mode 2
ZASSCD3
CDU2, Mode 3
***
The Validation report looks like this:
Another method is to generate the crude unit xls files, which create separate excel sheets for each crude unit. They are named !SCR1.xls (for crude unit SCR1). For this go to model settings-> general-> in the miscellaneous tab, check the CRUDEXLS option as shown below. This file can be found in the model folder.
Keywords: CRDBLENDS
!SCR1
Validation Report
PRNTABS
References: None |
Problem Statement: Table ROWS is used for two purposes,
1. add new equations (linear equations) into the model matrix.
2. modify existing model structure or equations.
What differences are there between using Table ROWS in an MPIMS/XPIMS model rather than a standard PIMS model? | Solution: In a Global model, T.ROWS has to have a column, 'USER'. Any non-blank number under USER indicates that particular row is a new equation in the matrix. The following table shows the differences in different types of models.
Keywords: MPIMS
XPIMS
PPIMS
PIMS
ROWS
References: None |
Problem Statement: DMC controllers were configured with CTOFF declared READ and linked to a database tag. However, a temporary Cimio problem caused CTOFF to have a value of -9999, which resulted in the controller failing (time of last run would never update). Even DELETEing and reloading the controller did not fix the problem, because the CCF had been saved with the bad value in CTOFF. It is suspected that the controller would never wake up with such a value of CTOFF. The short term | Solution: is to manually edit the CCF, put in a good value for CTOFF, then load the CCF. It is necessary to DELETE, LOAD, and START the controller in order for this to work.
Solution
The long termSolution is to make CTOFF LOCAL.
Keywords: (None) CONSTANT LOCAL READ
Related Topics:
WTMODE
© 1996-2000 Aspen Technology, Inc.
References: None |
Problem Statement: What property package should I use for dissolved hydrocarbons in water? | Solution: At low pressures, an activity coefficient model (such as NRTL, or UNIQUAC) is a better choice, in general, for modelling VLE (Vapor-Liquid-Equilibrium) or LLE or VLLE. However, while using an activity coefficient model the tuning parameters should be fitted against a representative sample of experimental data. In other words, some experimental data are required to find the parameters of the model (Other AspenTech software products, such as HYPROPIII or DISTIL can be used to regress the experimental data to find the parameters for a given activity coefficient model). Consequently, more caution is required when selecting these models.
For higher pressures, an Equation of State (EOS) is typically more appropriate. The Kabadi-Danner (KD) model is a modification of the original SRK EOS, enhanced to improve the VLLE calculations for water-hydrocarbon systems, particularly in the dilute regions. The modification is based on an asymmetric mixing rule, whereby the interaction in the water phase is calculated based on both the interaction between the hydrocarbons and the water and on the perturbation by hydrocarbons on the H2O-H2O interaction. The details and the ranges of applicability of this model can be found in Kabadi, V. N., and Danner, R. P., A Modified Soave-Redlich-Kwong Equation of State for Water-Hydrocarbon Phase Equilibria, Ind. Eng. Chem. Process Des. Dev. 1985, Volume 24, No. 3, pp 537-541.
According to the original paper from KD, good results can be obtained with this model in all the regions of the phase diagram (i.e. even for the water-rich phase). It can also be applied with a fair degree of accuracy up to about 500 F (while UNIFAC has a range of application limited to 32-230 F) and at much higher pressures than activity coefficient model in general.
Keywords: Water, H2O, Hydrocarbons, HC, Dissolved, Property Package, Dilute, Kadadi-Danner, KD, Water-Rich, EOS, activity coefficient model
References: None |
Problem Statement: Why does the overhead vapor of my column have a vapor fraction different than 1.0? My tray efficiencies are already 100%. | Solution: You may observe the overhead vapor stream is not at its dew point (VF<1) in the main environment, even though the tray efficiencies are all 1. (Note that even though within the column environment, the overhead vapor may show VF=1, you can clone this stream and do a PT flash to verify that it is actually not VF=1).
Possible actions you can take to remedy this issue:
Convergence tolerances: Tightening the Equilibrium Error Tolerance on the Column-->Parameters-->Solver page may bring it back to VF=1.
Column solving method: For systems containing water, you can avoid this problem by using the Sparse Continuation Solver method on the Column-->Parameters-->Solver page. (Ensure that with this solving method the 2 Liquids check based on option is set to Tray total fluid.)
Water draws. For systems containing water, putting a water draw on the top tray or shifting the existing water draw tray to the top tray may resolve the problem.
Two-liquids check and Auto Water Draws options. For systems containing water with the HYSIM Inside-Out or Modified HYSIM I/O solving method chosen, switch the two-liquids check option to Tray total fluid on the Column-->Parameters-->Solver page . Then, turn on the Auto Water Draw (AWD) option by going to the 2/3 Phase page, clicking on the Auto Water Draw button and checking the On box. (Note: The column convergence bar will be shown in pink when the column is converged).
The Tray total fluid option requires that the 2 liquids check be based on the overall composition of the fluid rather than the liquid composition alone. This helps when theSolution lies in the 3-phase VLE region.
Keywords: Column, overhead, dew point, water draw
References: None |
Problem Statement: Column fails to converge with Sparse Continuation Solver | Solution: The Sparse Continuation Solver is an equation based solver that supports two liquid phases. This solver is best suited for solving highly non-ideal and reactive distillation systems, however this is much slower than standard HYSIM Inside-Out or Modified HYSIM Inside-Out solvers.
The solver usually requires good starting points i.e. initial estimates. If the column fails to solve then follow the steps detailed below.
To solve the case, disable the two liquids checking, solve with a standard solver method, update the initial estimates, solve with the Sparse Continuation Solver and finally re-enable the two liquids checking.
Steps required to converge a column using the Sparse Continuation Solver are listed below.
1. Disable 2/3 phase checking via ?Parameters?, ?2/3 Phase? and Clear All.
2. Set ?No 2 Liq Check? via ?Parameters? and ?Solver?.
3. Switch the solver to HYSIM Inside-Out, solve the column using this method.
4. Once the column is solved then change solver back to Sparse Continuation Solver method and then solve column.
5. Enable the 2/3 phase checking via ?Parameters?, ?2/3 Phase? and Check All.
6. Set ?2 Liquid Check? via ?Parameters? and ?Solver?.
7. Run the column.
Keywords: Column, Sparse Continuation Solver, 2/3 phase
References: None |
Problem Statement: Are there any tips to help converge a RadFrac distillation column? | Solution: If a RadFrac column fails to converge, doing one or more of the following could help:
1. Ensure that column operating conditions are feasible
2. Check that physical property issues (choice of Property Method, parameter availability, etc.) are properly addressed
3. If the column err/tol is decreasing fairly consistently, increase the maximum iterations on the RadFrac | Convergence | Convergence | Basic sheet
4. Converge without Design Specs and Vary to initialize the column before adding (or revealing) specs and varys
5. Provide temperature estimates for some stages in the column using the RadFrac | Convergence | Estimates | Temperature sheet (useful for absorbers)
6. Provide composition estimates for some stages in the column using the RadFrac | Convergence | Estimates | Liquid Composition and Vapor Composition sheet (useful for highly non-ideal systems)
7. Consider different convergence methods on the RadFrac | Specifications | Setup | Configuration sheet
Note: When a column does not converge, it is recommended to Reinitialize after making changes!
Keywords: Radfrac, Column, convergence
References: None |
Problem Statement: Sometimes, one or more components may appear as solid in an electrolyte system or a reactive system. If solids form in distillation column, how does rate-based distillation model deal with the situations? | Solution: In the case of electrolyte systems with Chemistry activated, rate-based column will disable any salt formation reaction in the chemistry set. After the column calculation, the program will check for the possible salt precipitation. If the check gives a yes, the program will issue a warning.
In the case of reactive distillation, reactions with solid are not allowed, even though a user can enter salt formation reaction in REAC-DIST kinetic set. The program will have errors if any reactions have solid as reactant or product.
Keywords: rate-based distillation, solid handling
References: None |
Problem Statement: How do you use an ASTM D7169 distillation curve data in an Assay where there is no option of ASTM D7169 for the Assay distillation curve type? | Solution: D7169 is the High Temperature Simulated Distillation standard based on the extension of ASTM D2887 to cover heavier fractions (from boiling range of 55 - 538 degree Celsius of D2887 to 36 - 750 degree Celsius).
The Data measured using this technique are on the same basis as Total Boiling Point (TBP) on a Weight Basis (with some small differences).
Therefore, the reported data from D7169 can be entered in Aspen Plus Assay as TBP weight basis.
Keywords: ASTM, D7169, Assay, Aspen Plus, Distillation Curve, D2887, TBP
References: : Dan C. Villalanti, Joseph C. Raia, and Jim B. Maynard, High-temperature Simulated Distillation Applications in Petroleum Characterization, in Encyclopedia of Analytical Chemistry, R.A. Meyers (Ed.), pp. 6726-6741 |
Problem Statement: Why am I getting errors about missing PLXANT (Antoine Vapor Pressure equation) parameters when I am using an equation of state (EOS) model? | Solution: PLXANT parameters are required to initialize flash calculations for most standard, flexible and predictive Equations of State. These methods include BWRS-LS, BWRS, LK-PLOCK, PR-BM, RKS-BM, CPA, HYSGLYCO, PC-SFT, PRMHV2, PRWS, PSRK, RK-ASPEN, RKSMHV2, RKSWS, SR-POLAR, and others.
This information is documented in the help under Aspen Plus
Keywords: vapour pressure
EOS
missing property parameters
References: -> Physical Property Methods and Models -> Physical Property Methods -> Property Method Descriptions -> Equation-of-State Property Methods or Flexible and Predictive Equation Equation-of-State Property Methods -> Common Models.
On Regression mode, you might also get this error due to the selected Property for vapor pressure data.
When regressing EOS parameters, always use the property TP:
When regressing Activity Coefficient models parameters, use PL instead: |
Problem Statement: Why are the Aspen InfoPlus.21 Cim-IO client tasks (cimio_c_client.exe, cimio_c_async.exe, cimio_c_unsol.exe and cimio_c_changeover) not starting with no error messages? | Solution: It could be that the anti-virus checking software active on the Aspen InfoPlus.21 server is blocking the Aspen Cim-IO client tasks. Try placing the executable images for the Aspen InfoPlus.21 Cim-IO client tasks (cimio_c_client.exe, cimio_c_async.exe, cimio_c_unsol.exe and cimio_c_changeover) into the exclusion list for the anti-virus checking software.
Keywords: Symantec
McAfee
anti-virus
exclude
References: None |
Problem Statement: This knowledge base article explains why starting an IQ Task (TSK_IQ#) in the Aspen Infoplus.21 Manager, returns the error:
Error Creating Event Object, Error Code = 183.'' | Solution: You will get this error when the IQ Task was stopped ungracefully, for example, by ending the corresponding process in the Windows Task Manager. The query that the IQ Task was executing at the time may have started an external application (i.e. Visual Basic application, cmd.exe) which is still running. You will need to stop this application and restart the IQ Task. If the error persists, a reboot of the Aspen Infoplus.21 Server should resolve the error.
Keywords: TSK_IQ1
References: None |
Problem Statement: How to simulate fractions of polymer in vapor phase in flash separation processes. | Solution: The flash algorithms in Aspen Plus use the average molecular weight to determine volatility of the polymer. The algorithm does not distribute or fractionate the polymer between phases.
One common work around is to define an oligomer component to represent lower molecular weight wax fractions. Wax generation can be considered as a side reaction (just using power law kinetics).
Key Words
Polymer, Vapor Phase, Oligomer
Keywords: None
References: None |
Problem Statement: When switching flash algorithms from Inside Out to Gibbs, the bubble point predicted changes drastically from -20F to 100F. What is wrong? | Solution: It may be possible that there are twoSolutions for the bubble point. Some petroleum mixtures can undergo retrograde phenomenon where at a given temperature there are two bubble point pressures where liquid starts to form. For example, if pressure is reduced at constant temperature, it is possible to hit the dew-point curve, resulting in liquid drop-out or retrograde condensation. If retrograde condensation is suspect, users should performing a PT Envelope Analysis for the mixture to check.
For more information on retrograde condensation seeSolutions 127542 and 136334.
Keywords: None
References: None |
Problem Statement: Is there a way to convert an .apx file (PE plot file) to an XML file? | Solution: Yes, there is. Open an Aspen Process Explorer (APEx) plot in Web.21 and save it as an XML file.
Keywords:
References: None |
Problem Statement: Process Graphics can contain many data fields linked to a specific ADSA data source. It's possible for a data source name to change, so all the data fields would need to change their ADSA data source reference. Is there a method for changing the data source used within a graphic for all the data fields? | Solution: Yes, there is a method for changing the data source references. Inside the Process Graphics Editor, use the pulldown menu option:
Tools | Replace Source
This will allow you to change from one data source name to another.
Keywords: replace source
References: None |
Problem Statement: How can I limit an Aspen Petroleum Supply Chain Planner model to load only one type of material onto each transport type? | Solution: Example Process
Materials: M1, M2
From Node: A
To Node: B
Model: X
Collector: C1, C2
Collector Capacity: C
Steps to confine only one material can be loaded on a transport type
1. Define transport of M1 and M2 from A to B in mode of X in table Transport
2. For each transport vector, link it to a capacity (C1 or C2).
3. Define the capacity in table Collector, give it a Max. Optionally, define the same capacity in table CapacityRows and make it an ?L? row, this allows the transport activity to be less than the max of C1 or C2 (light load)
4. For the same capacity, set MipType to ?LotSize?, set the ?MipFactor? to be the same as its Max. This will make C1 or C2 either 0, or at its Max
5. In table CapCollector, link C1 and C2 to the same capacity C
6. Define Capacity C in table Collector, give it the same Max of C1 or C2, whichever is bigger. This will make C1 and C2 mutually exclusive. Hence, only one material can be transported in any period
Key words
DPO, loading, transport type material,
Keywords: None
References: None |
Problem Statement: When installing Aspen PIMS, some users experience the following message. What does that mean, and how to deal with it? | Solution: The message comes up due to the installation requires Microsoft Message Queue (MSMQ). To install MSMQ, from START | Control Panel, select 'Add or Remove Programs'. When the window opens up, from the left panel, select 'Add/Remove Windows Components'. Then the the new window, check the box of 'Message Queue', click 'Next'.
After the,. start PIMS installation again.
Note that MSMQ is only needed if MDM adaptors is checked under Aspen PIMS installer tree. Otherwise, PIMS installation does not need MSMQ.
Keywords: Installation
MSMQ
References: None |
Problem Statement: How to hide the General External Target Request switch from the Operations view for DMC3 or APC applications? | Solution: You can hide the switch using the apc.display.config file (C:\ProgramData\AspenTech\APC\Web Server\Products\APC)
Look for line 439:
It’s under the “general type variables” for the Operations view.
Deleting that entry will hide the switch for Operations view for all APC controllers.
Keywords: External Target, Hide ET request switch, PCWS, Operations view, DMC3, APC controllers,
References: None |
Problem Statement: When showing references for a point, the Aspen InfoPlus.21 Administrator displays the error: | Solution: This error means the service Aspen InfoPlus.21 Access Service is not running. Start the service using the Windows Services Control screen on the Aspen InfoPlus.21 server.
Keywords: show references
System.ServiceModel.Channels.ServiceChannel
Aspen InfoPlus.21 Access Service
References: None |
Problem Statement: In InfoPlus.21 Tag Configuration Tool, why is the timestamp different from SQLplus or InfoPlus.21 administrator? | Solution: The timestamp displayed in InfoPlus.21 Tag Configuration Tool Add-In is in UTC format.
Keywords: timestamp
References: None |
Problem Statement: After successfully installing Aspen PIMS, the user tried to open Aspen PIMS but gets the message 'Failed to find a valid license for Aspen PIMS'. How can users check if they have a valid PIMS license file? | Solution: Licenses for the Aspen PIMS Family products (including PIMS, APS, MBO, AOS and DPO) are version dependent. Using the 'SLM License Profiler' from Start | All Programs | Aspentech | Common Utilities | SLM License Profiler, you can check the maximum version of your application license and verify it is correct for the installed application.
First, to see which maximum version you need, you can look in the chart below to find the version which you installed.
Versions
The 2-digit version
PIMS
APS
MBO
AOS
DPO
V2004
15
V2004.1
16
V2006/V2006.5
17
10
5
20
6
V7.1/7.2/7.3
18
11
6
21
7
V8.0
19
12
7
22
8
Second, open the SLM License Profiler and look for the row SLM_PIMS for PIMS. Under the 'Max Product Version' column, check the first 2 digits of the number. In order to run PIMS v8.0, this 2-digit number has to be greater than or equal to the 2-digit number from the above chart (ie, 19 for v8.0).
Keywords: Max Product Version
License
License file
check
invalid license
fails to find
valid license
References: None |
Problem Statement: Why don't the units for the Wobbe Index change when I change the units for the Heating Value? | Solution: The units for the Wobbe Index should be specified in Volume Specific Energy:
Keywords: Heating value, HHV, LHV, lower heating value, higher heating value, conversion, Wobbe number
References: None |
Problem Statement: How are qualities calculated for the inventoried streams? | Solution: For an inventoried Recursed stream:
If the user is recursing a quality of an inventoried stream, PIMS takes into consideration both the production rate/quality and the opening inventory amount/quality and uses these to calculate the qualities at the end of period 1. Then it will do the same for period 2 where it will use the quality/amount of stream in production for period 2 and the inventory from period 1.
If there is no property in Table PINV, but there is opening inventory volume/weight, then the quality values are taken from the PGUESS entries. Since updating PGUESS can have a substantial impact on PPIMS models, it is strongly recommended to put all significant properties in Table PINV.
If the inventoried stream is a spec blend, then the calculation procedure is dependent upon the RECINVSP setting. You can find more details in KB article 108138.
For a Pcalc'ed stream:
The problem with using PCALC on a stream that is inventoried, is that the PCALC'd value does not get carried into the next period. Therefore the inventory quality will not accurately reflect the production quality. This can lead to problems if the inventory is being included in any blend specs, etc.
The alternative is to setup recursion instead of the PCALC to transfer the desired quality
One way to avoid the PCALC with inventory problem is to use a second stream for the inventory. For example:
FFF = feed stream to hydrotreater
PPP = product from hydrotreater with 95% of sulfur removed
III = inventoried product stream
Setup the submodel so that feed FFF, yields product PPP. Use PCALC to transfer the SUL level as desired into the product based on FFF levels. Now setup a recursion pool so that PPP becomes III and all PPP properties are transfered to III via recursion. An example of the submodel entries is:
In Hydrotreater submodel:
SFPI
FFF
VBALFFF
1
VBALPPP
-1
In PCALC
PCALC
SUL
PPPFFF
0.05
In same or different submodel:
PPP
III
VBALPPP
1
VBALIII
-1
RBALIII
-1
1
RSULIII
-999
999
(add all appropriate R-rows for each property that needs to be transfered)
Keywords: Recursed streams
Qualities across periods
Pcalced streams
References: None |
Problem Statement: Is it possible to model a reaction with a solid component? For example, I would like to model a reaction with solid carbon.
C + O2 ---> CO2
C (carbon solid). | Solution: You can model solids in reactions. The solids need to be specified as a “solid” component on the Components form. Then, they can be in either the Mixed or in the CISOLID substream. They can be in either conversion reactors or in kinetic reactors.
Attached is an example file.
Keywords: None
References: None |
Problem Statement: How can you write an Aspen SQLplus query to select historical values from Aspen InfoPlus.21 (IP21) tags only when another tag has a specific value? | Solution: This query prints the values of A1113F and A1113G between two times when the state of the discrete value Machine State is Running (integer value is 1). The tags A1113F, A1113G, and Machine State are part of the IP21 demo database.
The query produces the output:
ip_trend_time A1113F A1113G Machine State
-------------------- ------ ------ -------------
13-JUL-09 08:22:00.8 1.0 5.0 Running
13-JUL-09 09:14:00.0 9.0 5.0 Running
13-JUL-09 09:23:00.0 5.0 0.0 Running
13-JUL-09 09:24:00.0 2.0 4.0 Running
13-JUL-09 09:25:00.0 6.0 2.0 Running
Keywords: Sample query
Select history
References: None |
Problem Statement: I am trying to estimate missing physical property parameters, and the UNIFAC groups are missing in the Aspen Plus databanks to describe my component, what can I do? | Solution: One option is to define your own dummy Unifac groups for the component, and provide the Unifac parameters if you have them. See the example file attached.
Detailed steps:
1. Define a new UNIFAC group in Data/Components/UNIFAC groups: eg in the attached file, DUMMY with group number 4500. New groups should only use numbers between 4500 and 5000.
2. In Data/Properties/Molecular Structure/SI2CL6/Functional Group sheet, select the method as UNIFAC, and specify the number of occurrences of the DUMMY group.
3. Use the Data/Properties/Parameter/UNIFAC Group/U-1 form to enter the relevant Unifac parameters (depends on the property method chosen) and their values.
Use GMUFQ and GMUFR for the UNIFAC activity coefficient model.
Use GMUFPQ and GMUFPR for PSRK
Use GMUFLQ and GMUFLR for the Lyngby-modified UNIFAC activity coefficient model
Use GMUFDQ and GMUFDR for the Dortmund-modified UNIFAC activity coefficient model
4. Use the Data/Properties/Parameters/UNIFAC Group Binary/GMUFB-1 form to enter the group binary interaction parameters bij for the Unifac activity coefficient model.
Keywords: UNIFAC, UNIF-DMD, UNIF-LBY, UNIF-LL
References: None |
Problem Statement: How does the RSTOIC, the stoichiometric reactor, calculate the enthalpies, specific heat, outlet temperature, and other thermodynamic values? | Solution: The RSTOIC block in Aspen Plus uses a stoichiometric energy balance of what goes into the reactor to calculate the different parameters. Refer toSolution 3169 for a detailed discussion.
There is a good example of how this is done in: Chemical Engineering Design: Principles, Practice and Economics of Plant and Process Design by Towler and Sinnott (Second Edition, Copyright 2013) , Chapter 15, pages 643 to 645. Due to copyright we can't provide you with the actual problem, but it is recommended as it presents a good application of the formulas. The .bkp files from the example are attached.
Below is the problem posed with all of the pertinent information. After plugging this into Aspen Plus, we find that the answers are the same.
Vinyl Chloride (VC) is manufactured by the pyrolysis of 1,2-dichloroethane (DCE). The reaction is endothermic. The inlet and outlet conditions to produce 500kg/h at 55% conversion are:
Inlet: DCE 145.5 kmol/h, liquid, 20C
Outlet: VC 80 kmol/h, DCE 65.5 kmol/h, HCL 80 kmol/h
Reactor condition: 2 bar, 500 C
The reactor is a pipe reactor heated with fuel gas, gross calorific value 33.5 MJ/m3. Estimate the quantity of fuel gas required
Keywords: RSTOIC, thermodynamic, outlet, enthalpy, temperature, specific heat
References: None |
Problem Statement: How can I set stream composition via a spreadsheet? | Solution: See attached file Composition set via spreadsheet.hsc. Numbers in column B represent non-normalised composition. Data is normalised in column C and exported to a stream.
There are two important points to note:
data must be exported for ALL components in the model
composition must be normalised
Finally, once the spreadsheet is set up and linked to the stream, it may be necessary (just once) to ignore the spreadsheet, then restore it.
Keywords: Spreadsheet, composition
References: None |
Problem Statement: The value from column FACTOR in table WSPECS is used to convert weight based property to volume based equivalent. Below is a description of exactly how it affects the matrix structure. | Solution: Assuming we have one specification blend B+C:
Two components can be blended to B+C:
We have max sulphur content expressed in weight% set to 2.5:
In table BLNPROP we have quality data regarding sulphur content expressed in pounds per barrel (SPB):
If we know correlation between SUL( weight percent) and SPB (pound per barrel) we can set it up in table WSPECS in column FACTOR so PIMS will be able use both in quality control row.
After running such a model XSULB+C quality control row will have coefficients like below:
Where:
BBBB+C is a volume of BBB which will be blended to B+C
BCCCB+C is a volume of CCC which will be blended to B+C
BWBLB+C is a weight of blended B+C
As SUL is controlled on weight base PIMS will convert SPB*FACTOR and insert it to the XSUL equation. The whole calculation looks like below:
-0.253*0.454*BBBBB+C – 0.711*0.454*BCCCB+C + 2.5*BWBLB+C >= 0
In other words:
SPB*FACTOR *VOL =SUL*Weight
Should you need more details please see enclosed model.
Keywords: WSPECS
FACTOR
BLENDING
References: None |
Problem Statement: How do I display the status, number of file sets, and active file set number for each repository? | Solution: The attached query displays the status, number of file sets, and the active file set for each repository in an Aspen InfoPlus.21 server.
Keywords: Active file set
Number of file sets
Repository status
References: None |
Problem Statement: This Knowledge Base article provides examples of Process Explorer Ad-hoc calculations. | Solution: Attached PDF document on thisSolution provides syntax examples and formula construction rules for Ad-hoc calculation that can be used in Aspen Process Explorer.
For a detailed explanation of the Time-Based Functions, please consult Aspen Calc Help File.
For a list of Aspen Calc functions that can be used in Process Explorer refers toSolution 115368.
Keywords: Ad-hoc
Process Explorer
Time-Based Functions
References: None |
Problem Statement: This is a step by step | Solution: to guide PIMS users to setup a simple blending process in PIMS.Solution
Blending is the process of mixing hydrocarbon fractions and other components to produce products that meet certain specifications. Diesel and gasoline are the major products produced by the blending process.
1. Table BLENDS and BLNMIX are required to set up a blending process. Table BLNSPEC is required for specification blending.
2. Use table BLENDS to identify blended product and to indicate whether the blended product is created on a formula or specification basis. The example below shows that Unleaded Regular (URG) is a blended product created on a specification basis whereas Liquefied Petroleum Gas (LPG) is a blended product created on a formula basis.
3. Use table BLNMIX to identify the blending components used to create specification blends and to provide the formulation for formula blends. The example below shows that Gasoil (GSO) and Vacuum Residue (VR1) are blending components to form URG, whereas Propane (NC3), Butane (NC4) and Isobutane (IC4) are blending components to form LPG and they are blend in a ratio of 0.8:0.1: 0.1.
4. Use table BLNSPEC to define the property specifications for a blend. The example below shows that the maximum specific gravity (SPG) of URG is 0.77 and minimum Research Octane Number (RON) of URG is 92.
5. Use table BLNPROP to define the properties of blending components that blend on a specification basis. The example below shows the SPG and RON of blending componets : GSO and VR1.
Keywords: BLENDS, BLNMIX, BLNSPEC, BLNPROP
References: None |
Problem Statement: Why does a port 31 EO (Equation Oriented) connection not work when one of the components is not present in the connecting stream? | Solution: Aspen Plus Versions 2004.1 and later have a default option called Non-Zero Components which can be found under the EO Options forms as Remove Components.
This option will remove any component that has zero flow when a block or stream is created during the EO synchronization. Non-zero components is an important feature in EO that can be used to reduce the size and improve the robustness of the EO model.
However, there are a couple of cases where it can create problems, the creation of EO ports being one of them.
1. If the user creates an EO connection and the downstream block does not have all the components of the upstream block, the extra components will be removed. The user should be aware of this possibility as no checking is made by the system to see if this is happening.
2. If the SM (Sequential Modular) flowsheet is not completely solved, components may be removed which should not be removed. This is most likely when using recycle streams where the initial tear stream is missing components. In this case, there is some checking during synchronization and post-solve to uncover this problem.
The user may specify which components are to be used by the EO models using non-zero components, or specify that missing components are to be removed automatically. There is also the possibility to disable the Remove components option. This may be done in each block or globally under the EO Configuration | EO Options folder.
The Remove Components option on any EO Options sheet has three possible values:
1. Always: Always remove missing components
2. No model comps: Remove missing components when non-zero components were not explicitly specified via a component group
3. Never: Do not remove missing components
To completely disable the Remove components option, select Never.
See the user documentation for more information in Aspen Plus Help: Aspen Plus
Keywords: Port, Port 31, EO Connection, EO Options, Non-Zero Components.
References: | Equation Oriented Modeling Reference Manual | Using Non-Zero Components. |
Problem Statement: What are the units for Power Law expression pre-exponential factor? Where is it documented? | Solution: The pre-exponential factor in the power-law rate expression has very complex units which depend on the concentration basis selected and whether a reference temperature is specified. The concentration is converted to SI units before the rate is calculated. The pre-exponential factor has the units needed to make the overall rate expression have SI rate units, that is kgmole/(sec-m^3) for a rate basis of reaction volume or kgmole/(sec-kg catalyst) for a basis of catalyst weight (version 2004.1 and higher). The reactor volume or catalyst weight used is determined by or specified in the reactor where the reaction is used.
This information is available from the on-line help, by choosing help while on the Pre-exponential factor field. It is also found by going to the Help Topics for Aspen Plus, and then navigating to Using Aspen Plus \ Specifying Reactions and Chemistry \ Specifying Power Law Reactions \ Rate-Controlled Reactions.
The units for the pre-exponential factor are as follows:
The kgmole/(sec-m^3) is replaced with kgmole/(sec-kg catalyst) in the table above if a basis of catalyst weight is used.
Keywords: powerlaw
power-law
units of measure
preexponential
References: None |
Problem Statement: When trying to create a new Aspen Properties Enterprise Database (APED) in the Aspen Properties Database Manager, I get the message:
Linking to the server failed. Check you input for Login Name, Password, and Server.
However, I am sure that I entered the Login Name and Password correctly. | Solution: This message does indicated that something is incorrect in the login specifications. Try the following two suggestions:
1. Double check that the Login Name (apeduser for V7.0 and higher) and Password (Aprop100 for V7.0 and higher) are correct. They are both case-sensitive.
2. If using the default SQL Express server, use .\sqlexpress rather than localhost for the Server. The .\ indicated that the local computer is used. When specifying a server name in the Aspen Properties Database Manager on a SQL Express server, you must add \sqlexpress after the computer name or use .\sqlexpress for your computer, instead of using localhost or just the computer name as the server name.
Keywords: None
References: None |
Problem Statement: Although specific port numbers can be assigned to the various Aspen InfoPlus.21 API server tasks to effect client communication through a firewall, the Aspen InfoPlus.21 Task Service is still dynamically allocated a new port number through the Noblenet portmapper every time this service is restarted. Since the Aspen InfoPlus.21 Administrator uses the Aspen InfoPlus.21 Task Service to communicate with the Aspen InfoPlus.21 database, the port for the Aspen InfoPlus.21 Task Service needs to be opened through the firewall as well.
This knowledge base article documents all steps required to allow the Aspen InfoPlus.21 Administrator to communicate through a firewall.
Note: Two way communication through the firewall must be allowed for each port used by the Aspen InfoPlus.21 client tools (each port mentioned in this article.) | Solution: 1. ASSIGN A PORT NUMBER FOR TSK_ADMIN_SERVER:
A. Open the Aspen InfoPlus.21 Manager.
B. Select TSK_ADMIN_SERVER.
C. Next to the -v parameter in the command line parameters box, type -nNNNN, where NNNN is the port number not blocked by the firewall.(e.g. -n1234)
D. Click Update
E. Stop and restart the task, for the change to take affect.
Note: Additional background information on this step (and similar application to other client tools) can be found in knowledge base article 104056.
2. ASSIGN A PORT NUMBER FOR THE ASPEN INFOPLUS.21 TASK SERVICE:
The Aspen InfoPlus.21 Task Service can be configured to use a specific port number by adding a registry value RPC_PORT_NUMBER (REG_DWORD) under the key
\\HKEY_LOCAL_MACHINE\SOFTWARE\AspenTech\InfoPlus.21\N.x\group200
For 32-bit Aspen InfoPlus.21:
\\HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\AspenTech\InfoPlus.21\N.x\group200
After this registry value is added, restart the Aspen InfoPlus.21 Task Service for the newly specified port to be used.
(Note: Add the registry value to the appropriate registry folder for your version of Aspen InfoPlus.21, e.g. 11.1, 11.2, 11.3, etc.)
3. VERIFY THAT THE NEWLY SPECIFIED PORTS ARE IN USE:
In a command prompt window opened on the Aspen InfoiPlus.21 server, use the following command:
netstat -aon | findstr NNNNN
Replace NNNNN with the port number(s) you configured to use earlier. The Process ID (PID) is displayed in the right most column and you can double check the PID by using Task Manager.
Keywords: RPC
Access
References: None |
Problem Statement: Distributed Component Object Model (DCOM) is a proprietary Microsoft technology for communication among software components distributed across networked computers. DCOM, which originally was called Network OLE, extends Microsoft's COM, and provides the communication substrate under Microsoft's COM+ application server infrastructure
Several Aspen products, Process Explorer, Aspen Calc, Production Record Manager (Batch.21) and Cim-IO for OPC among others use DCOM communications and the steps to configure DCOM permissions on the server are documented in several Aspen Knowledge Base articles (KBs), like 108885,118957, 123261 and 134127; however sometimes these configuration steps do not resolve DCOM communication issues. | Solution: To help further analysis of DCOM errors the following Windows server 2003 and 2008 registry values associated with the HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Ole key control the default launch and access permission settings and call-level security capabilities for COM-based applications on the server. Details on these can be found at:
http://msdn.microsoft.com/en-us/library/ms692700.aspx
Add the following entries in the server system,
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Ole]
ActivationFailureLoggingLevel=dword:00000001
CallFailureLoggingLevel=dword:00000001
and run the application on the client system and check the Windows Events on the server system for DCOM related error messages and make corrections on DCOM permissions as needed.
Once you've resolved the problem remember to go back to the server system and remove the Windows Registry entries or set the keys to their default values to disable the extra login messages.
ActivationFailureLoggingLevel=dword:00000000
CallFailureLoggingLevel=dword:00000002
Keywords: DCOM, communication, troubleshoot
References: None |
Problem Statement: You encounter the below error message
Failed to find ProgID: Aspen.Calc.TimeBaseFunc.1, in formula <on demand calc> at line 1
when you
1. Search in the Aspen Tag Browser for on demand calculations and the Value column returns the error message.
2. Create a Data Field in Aspen Process Graphics Editor and set the Tag Name in the Data Source tab of the Data Field Properties. The error will be shown on the graphic in the editor. | Solution: On the machine that encounters this error ensure that:
1. Aspen Calc is installed.
2. a DLL called AtCalcTimeBaseFunction.dll is found in C:\Program Files\AspenTech\Aspen Calc\Bin
3. the DLL called AtCalcTimeBaseFunction.dll is registered with Windows.
To register the DLL,
1. Open a command prompt.
2. Browse to C:\Program Files\AspenTech\Aspen Calc\Bin.
3. Execute regsvr32 AtCalcTimeBaseFunction.dll
Keywords: Aspen.Calc.TimeBaseFunc.1
Aggregates
On demand calculation
References: None |
Problem Statement: How to add bias to IQ | Solution: You can add bias to an online IQ application as follows:
1. When running the IQ application, there is a PREDBIAS entry (in the PR section) which you can use to set the bias manually. The value of PREDBIAS can be changed using PCWS or IQView.
2. If you are collecting lab samples for the LCN EP property, you can define the LDC and LBU sections in IQ and enter lab samples in the online IQ application using either PCWS or IQView and let IQ calculate the bias automatically based on lab data.
3. If analyzer value is available, you can define an AZU section and use it to calculate the bias.
You can look at the refinery example to see how lab samples are configured for an inferential property.
Keywords: iq, bias, update, add
References: None |
Problem Statement: What does Error from CLSIDFromProgID <opcservername> on local system hr = 0x800401f3, Invalid class string in the cimio_msg.log indicate? | Solution: This error message indicates that the OPC server name indicated in the cimio_msg.log is not installed on the Cim-IO server. The reSolution to this error message is to install the desired OPC server on the Cim-IO server.
It is possible to verify that the OPC server is not installed by opening OPCProperties.exe on the Cim-IO server.
For a 32-bit install: C:\Program Files\AspenTech\CIM-IO\io\cio_opc_api\OPCProperties.exe
For a 64-bit install: C:\Program Files (x86)\AspenTech\CIM-IO\io\cio_opc_api\OPCProperties.exe
In the Cim-IO for OPC Properties window, select the Configure OPC Servers button.
Verify in the right-hand pane that the OPC server does not exist under the node name. In this case, the OPC.DeltaV.1 OPC server (as listed in the cimio_msg.log) does not exist.
Keywords: OPC server
CLSIDFromProgID
Invalid class string
References: None |
Problem Statement: I ran my model in PIMS-AO several times and each time it solved the same case to a different Objective Function, even though I have not changed any input or settings. What could be the cause of this behavior? | Solution: This kind of behavior is usually caused by Start with Existing LP Basis option enabled under XSLP Settings / Advanced 2. It causes Xpress to initialize with the existing basis file, which causes non-deterministic behavior.
For most of the models this option should be disabled:
Keywords: Start with Existing LP Basis
inconsistent results
PIMS-AO
advanced optimization
References: None |
Problem Statement: An Example on how to test tags in bulk using test API | Solution: There are two ways to specify the tag information that is transmitted to the Cim-IO server:
- Entering tag information from the keyboard one tag at a time.
- Entering tag information into a text file and specifying the name of the file when prompted by cimio_t_api.
Please refer to below example for entering tag information into a text file:
1- I have two tags in bulk_tags.txt
Note:
a) Tags file need to be in the same location as ??cimio_t_api.exe?? on IP.21 server(or CIMIO server)
b) Tags file should be text file not excel file
c) Data type is case sensitive
2- Perform test API with this text file.
Note:
a) Don't forget to type the exact numbers of tags, it is 2 in this case.
b) For Tag entry options, please select number 2
You can refer to the Aspen Cim-IO User's Guide for more information. Look under the section Cim-IO Test Utility Program specifically the topic Automating Parameter Input.
Keywords: test API
bulk tags
References: None |
Problem Statement: The MQA result shows red highlights on the some variable tag names (Example below). What does this signify? | Solution: The red or yellow highlight of a variable in the MQA plot indicates one of the configured KPI(s) for that variables is in an alarm state. When the user hovers the mouse over the variable tag name, the system will show a pop-up screen wuth the KPI calculation that is in alarm. User may click on the Plot Settings button on the pop-up screen to find out which KPIs are configured for MQA analysis of the variable. The default KPIs are listed in the screenshot below:
Keywords: MQA
DMC3
Calibrate
Adaptive Modeling
References: None |
Problem Statement: Example of a regression of UNIFAC parameters from LLE data | Solution: This example illustrates the use of LLE data to determine a new set of liquid-liquid UNIFAC group binary parameters for the UNIF-LL property method. The experimental data are for an ethyl acetate/water/ethanol system. The UNIFAC groups for the components are summarized in the following table:
Component
UNIFAC Group
Group Number
Number of Occurrences
Ethyl Acetate
CH3COO
CH2
CH3
1505
1010
1015
1
1
1
Water
H2O
1300
1
Ethanol
OH
CH2
CH3
1200
1010
1015
1
1
1
In the UNIFAC formulation, functional groups can be divided into subgroups and main groups. One main group can contain several subgroups. For example, the main group CHn contains the subgroups C, CH, CH2, CH3 and CH4. (See the Aspen Plus Physical Property Data
Keywords: drs
References: Manual of the help for a complete list of the UNIFAC functional groups.) The UNIFAC group binary parameters are defined for the interaction between main groups. The group binary parameters are the same for the interaction between the subgroups in one main group and the subgroups in any other main group. If the interactions for one subgroup are regressed, all other subgroups within that main group are equated to that value. This applies to both existing UNIFAC groups and new user-defined groups.
In this example, the group binary parameters are determined for groups H2O-CH3COO, CH3COO-H2O, H2O-CH3, and CH3-H2O. Since the subgroups CH2 and CH3 belong to the same main group, the parameters for H2O-CH2 must be the same as for H2O-CH3. Similarly, the parameters for CH2-H2O must be the same as for CH3-H2O. The data regression system determines only one of the binary parameters for H2O-CH2 and H2O-CH3 (and one of the binary parameters for CH2-H2O and CH3-H2O). The data regression system automatically sets the other parameter equal to the regressed parameter.
There are two cases in this example. The first case (C0) evaluates the built-in parameters for UNIF-LL, in predicting the experimental data. The second case (C1) determines a new set of parameters using the same data. |
Problem Statement: What property package should I use for dissolved hydrocarbons in water? | Solution: At low pressures, an activity coefficient model (such as NRTL, or UNIQUAC) is a better choice, in general, for modelling VLE (Vapor-Liquid-Equilibrium) or LLE or VLLE. However, while using an activity coefficient model the tuning parameters should be fitted against a representative sample of experimental data. In other words, some experimental data are required to find the parameters of the model (Other AspenTech software products, such as HYPROPIII or DISTIL can be used to regress the experimental data to find the parameters for a given activity coefficient model). Consequently, more caution is required when selecting these models.
For higher pressures, an Equation of State (EOS) is typically more appropriate. The Kabadi-Danner (KD) model is a modification of the original SRK EOS, enhanced to improve the VLLE calculations for water-hydrocarbon systems, particularly in the dilute regions. The modification is based on an asymmetric mixing rule, whereby the interaction in the water phase is calculated based on both the interaction between the hydrocarbons and the water and on the perturbation by hydrocarbons on the H2O-H2O interaction. The details and the ranges of applicability of this model can be found in Kabadi, V. N., and Danner, R. P., A Modified Soave-Redlich-Kwong Equation of State for Water-Hydrocarbon Phase Equilibria, Ind. Eng. Chem. Process Des. Dev. 1985, Volume 24, No. 3, pp 537-541.
According to the original paper from KD, good results can be obtained with this model in all the regions of the phase diagram (i.e. even for the water-rich phase). It can also be applied with a fair degree of accuracy up to about 500 F (while UNIFAC has a range of application limited to 32-230 F) and at much higher pressures than activity coefficient model in general.
Keywords: Water, H2O, Hydrocarbons, HC, Dissolved, Property Package, Dilute, Kadadi-Danner, KD, Water-Rich, EOS, activity coefficient model
References: None |
Problem Statement: Why does the overhead vapor of my column have a vapor fraction different than 1.0? My tray efficiencies are already 100%. | Solution: You may observe the overhead vapor stream is not at its dew point (VF<1) in the main environment, even though the tray efficiencies are all 1. (Note that even though within the column environment, the overhead vapor may show VF=1, you can clone this stream and do a PT flash to verify that it is actually not VF=1).
Possible actions you can take to remedy this issue:
Convergence tolerances: Tightening the Equilibrium Error Tolerance on the Column-->Parameters-->Solver page may bring it back to VF=1.
Column solving method: For systems containing water, you can avoid this problem by using the Sparse Continuation Solver method on the Column-->Parameters-->Solver page. (Ensure that with this solving method the 2 Liquids check based on option is set to Tray total fluid.)
Water draws. For systems containing water, putting a water draw on the top tray or shifting the existing water draw tray to the top tray may resolve the problem.
Two-liquids check and Auto Water Draws options. For systems containing water with the HYSIM Inside-Out or Modified HYSIM I/O solving method chosen, switch the two-liquids check option to Tray total fluid on the Column-->Parameters-->Solver page . Then, turn on the Auto Water Draw (AWD) option by going to the 2/3 Phase page, clicking on the Auto Water Draw button and checking the On box. (Note: The column convergence bar will be shown in pink when the column is converged).
The Tray total fluid option requires that the 2 liquids check be based on the overall composition of the fluid rather than the liquid composition alone. This helps when theSolution lies in the 3-phase VLE region.
Keywords: Column, overhead, dew point, water draw
References: None |
Problem Statement: Column fails to converge with Sparse Continuation Solver | Solution: The Sparse Continuation Solver is an equation based solver that supports two liquid phases. This solver is best suited for solving highly non-ideal and reactive distillation systems, however this is much slower than standard HYSIM Inside-Out or Modified HYSIM Inside-Out solvers.
The solver usually requires good starting points i.e. initial estimates. If the column fails to solve then follow the steps detailed below.
To solve the case, disable the two liquids checking, solve with a standard solver method, update the initial estimates, solve with the Sparse Continuation Solver and finally re-enable the two liquids checking.
Steps required to converge a column using the Sparse Continuation Solver are listed below.
1. Disable 2/3 phase checking via ?Parameters?, ?2/3 Phase? and Clear All.
2. Set ?No 2 Liq Check? via ?Parameters? and ?Solver?.
3. Switch the solver to HYSIM Inside-Out, solve the column using this method.
4. Once the column is solved then change solver back to Sparse Continuation Solver method and then solve column.
5. Enable the 2/3 phase checking via ?Parameters?, ?2/3 Phase? and Check All.
6. Set ?2 Liquid Check? via ?Parameters? and ?Solver?.
7. Run the column.
Keywords: Column, Sparse Continuation Solver, 2/3 phase
References: None |
Problem Statement: What does Aspen Fleet Optimizer Map Monitor allow you to do? | Solution: Aspen Fleet Optimizer Map Monitor allows the users to view their schedules, and also displays their truck routes over a period of time. With Aspen Fleet Optimizer Map Monitor, you can click on trucks for selected time-period or view each trip individually on the map. Select and view Groups, Terminals, and Trucks on the map. View Group, Terminal, and Truck details. Finally, you are able to view orders associated with specific Groups, Terminals, and Trucks.
Keywords: None
References: None |
Problem Statement: What does the Holiday Storm Planner do? | Solution: The Holiday-Storm Planner is a utility that lets the user enter expected variations in future sales by product, for one or more customers. The user can store sales variations expected as a result of a sporting event, holiday, storm, or any other situation that creates an abnormal sales condition. Entries into the Holiday-Storm Planner can be made by way of customer, terminal, zone, a combination of terminal and zone, or for all customers. Entries for a terminal or zone will affect all customer forecasts associated with the selected terminal and/or zone. AFO will incorporate an entry in the Holiday-Storm Planner during forecasting. For example, if an entry is made for a 10% increase in all product sales for the day before Christmas (December 24th), AFO will incorporate the entry along with all the other existing data to forecast for the increase in sales on the day before Christmas. In considering which entries to use for each customer, the priority hierarchy is customer specific, terminal, and zone specific (that matches the customer's terminal and zone), terminal specific (that matches the customer's terminal), zone specific (that matches the customer's zone), and all customers. If a customer specific record does not exist, AFO will look to the terminal and zone specific record, then move on to the terminal specific, and so on.
Keywords: None
References: None |
Problem Statement: What causes blue and green loads in Aspen Fleet Optimizer (AFO) replenishment planner? | Solution: This is cause by the status field being updated in AFO.A Status refers to the status of a shipment. This field is populated via the AFO Load Confirmation service. Color-coding has also been added. When a confirmation record is picked up for a shipment that is loaded, the shipment inside the Replenishment Planner turns blue and the status is updated to a??loadeda??. When a confirmation record is picked up for a shipment that is delivered, the shipment inside the Replenishment Planner turns green and the status is updated to a??delivereda??.
Keywords: None
References: None |
Problem Statement: The Aspen Framework (AFW) security database for Aspen Production Control Web Server (PCWS) might get corrupted during configuration or usage. The symptom of a corrupted AFW database is that no APC application will show up in PCWS when using the Default application security level (assuming no further configuration has been set).
Starting V7.2 the PCWS can use DAIS or WCF protocol (DAIS was obsoleted starting V8.0). When DAIS is used the AFW Application is “ACO View Server” and when WCF is used the AFW Application is “RTE”.
In WCF if a given Host is added that appears as a Secure Group (besides the NodeDefault) and if a given Application is added that appears as a Securable Object (besides the default ones). In the image below the Host APCSRV73MG and the Application (controller) F01 were added.
Note: The configuration should be done via PCWS or Configure Online Server. | Solution: Wordaround: If no further configuration (beyond default) has been set, the user can manually add each individual Host, Application or a mix of them to the security database.
If a more complex structure was already set, the corrupted RTE node in the AFW Security database needs to be cleared and rebuilt. Follow the procedure outlined below to perform this:
1. Open AFW Security Manager and delete the RTE application node. If required take notes about the current permissions per Role, Host, Application.
2. If the ACO View Server application exits and DAIS is not used, delete it.
3. Close AFW Security Manager.
4. Open the Windows Services panel and stop the AFW Security Client Service, the Aspen APC Web Provider Data Service (when using WCF) –found on the Web server -, and the AspenTech Production Control RTE Service – found on the Online server, this impacts the Aspen Process Controller apps -.
5. Stop and re-start IIS (using IIS Manager or Windows service IIS Admin Service).
6. Start the Aspen APC Web Provider Data Service and the AspenTech Production Control RTE Service. Starting one of those services, it should start too the AFW Security Client Service. Restarting the first two services rebuilds the RTE security node in AFW Security Manager.
Note: If the RTE security node is not recreated, that suggests an issue accessing the database or other configurations problems. Please contact Technical Support.
7. Confirm that Aspen APC DMCplus Data Service, Aspen APC Inferential Qualities Data Service and Aspen APC Nonlinear Controller Data Service are still running on the Online server.
Miscellaneous
1. There is no automatic backup process of the AFW database. Manual backups can be scheduled; if using Aspen Local Security (ALS), the database is found in Windows 2008 64-bits / Windows 2012 C:\Program Files (x86)\AspenTech\Local Security\Access97 (default path).
2. The AFW itself can be secured (using AfwSnapin.xml, Aspen Framework), for PCWS is not suggested.
In case it’s necessary, just remember to set in the AFW Aspen Framework object full rights to the user who starts the Aspen APC Web Provider Data Service (it will need to be specified one account, as it defaults to Local System; usually is the same account that starts the AFW Security Client Service and has full rights to access the structure of the Users, Groups, Domains that are specified in the AFW security matrix).
Keywords: PCWS, AFW Security Manager, Security
References: None |
Problem Statement: Aspen PIMS has a several minutes delay in startup when it gets the licenses from a network license server. How can I speed up the launch of the product? | Solution: Perform the following steps on your computer to speed up the time that PIMS is searching for the license:
1. Launch the SLM Configuration Wizard
2. Will you be connecting to an SLM server over the network? Yes. Next.
3. Verify which license server supports PIMS features and make sure it is the only license server defined in your machine (or it is shown as the first of the Configured Servers list). Make sure to add the appropriate buckets. Next
4. Would you like to configure the advanced settings? Yes. Next
5. Project Tracking - not applicable. Next
6. Enable network broadcasting is NOT checked. Ignore local keys IS checked. Next
7. Select Register and optimize license type usage registry settings. Click on Auto Configure/Optimize License Type Settings. Verify only Unified Licensing is checked.
8. Next and Finish.
Keywords: delays in opening PIMS
References: None |
Problem Statement: This list of common errors made by PIMS modelers was compiled by the veteran PIMS consultant, Nestor Resurreccion. We post this list in the hope that they can be avoided in the future. | Solution: Working with multiple directories: the user saves files/workbooks in wrong directory. This is especially true when the user is working on several models at the same time. Worst case: the user deletes the model/directory that has the good data.
The user types in data (unconsciously) somewhere inside spreadsheet, where there is no active row or column.
Copies a PIMS table (e.g., a submodel) and forgets to distinguish/rename (E,L,G) control rows.
Forgets to scale (1/1000) entries in BUY, SELL and CAPS. This usually leads to infeasibleSolutions.
Table ROWS: some users confuse rows with columns and vice versa.
Tables BUY & SELL: The user confuses pricing unit for materials with active VOL or WGT entries.
Blending Indices. Correlations in Table INDEX are not always consistent with BLNPROP and ASSAYS.
The modeler uses inconsistent units of measure for same utility (e.g., STM) across the LP model. Also, mixtures of scaled (1/1000) and unscaled coefficients are not uncommon. This results in serious utility imbalances.
Some modelers have the misconception that all possible product specifications must be modeled (e.g., color, gum, penetration, etc.).
In base/delta submodels, some forget to free up the delta vector/s and wonder where infeasibility is coming from.
Some models have very little, if any, documentation at all. Good model documentation is important!
Keywords: errors
mistakes
References: None |
Problem Statement: Table ROWS is used for adding new structure, defining additional constraints (linear equations), or modifying an existing equation. It can be used in all types of Aspen PIMS models, such as standard PIMS, PPIMS, MPIMS and XPIMS. This | Solution: is to summarize the differences when Table ROWS is used in different types of PIMS model.
Solution
The following table shows the supporting features of table ROWS in different types of Aspen PIMS models. For detailed examples of how to use each of these please refer to the Aspen PIMS HELP.
Types
Column
USER
Rownames
support +/-888
place holders
Column Names
PIMS
not support
7-characters model names
no
model column names
/user column names
PPIMS
not support
support 8-character
8th character indicates period
yes
model column names
/user column names
8th character indicates period
MPIMS
0
support 8-character
8th character indicates model
no
not support local model column names
8th character indicates model
XPIMS
0
support 9-character
8th character indicates period
9th character indicates model
yes
support 9-character
8th character indicates period
9th character indicates model
Column USER may be presented in MPIMS and XPIMS. A non-blank or non-empty entry (typically is a value '0') in column USER indicates that the row is a new row defined by the user.
In a PPIMS model, the modeler can create non-period-specific rows and Aspen PIMS will replicate the structure for each period. In XPIMS, this does not occur and the user has to manually create rows for each period. In a global XPIMS Table ROWS, Aspen PIMS does not replicate rows for each period.
Keywords: PIMS
PPIMS
MPIMS
XPIMS
ROWS
HELP
References: None |
Problem Statement: I have Table VPOOL in my model and I would like to see the structure that PIMS creates for this. Is there a way to see this table? | Solution: PIMS can include the VPOOL structure in the Data Validation. To have PIMS do this, you must first add Svpl as an entry in Table PRNTABS. An example of this entry is below.
* TABLE
PRNTABS
*
Miscellaneous Tables to be Reported
TEXT
***
Svpl
BOUNDS
User Defined Bounds
PGUESS
Initial PGUESS
PDIST
Initial PDIST
PCALC
Property Calcs
ZASSCD1
CDU1, Mode 1
ZASSCD2
CDU2, Mode 2
ZASSCD3
CDU2, Mode 3
*** End
Once this entry is provided, you can run the Validation under MODEL | Data Validation. Then open the Validation.lst report and you can see the VPOOL structure.
Keywords: PRNTABS, VPOOL, Validation
References: None |
Problem Statement: PIMS allows users to use database as input and output. How do we use the database options in PIMS? | Solution: The PIMS Input Database is the database into which you enter PIMS input data. A traditional PIMS model uses excel spreadsheet tables as input and those excel spreadsheets are attached to branches on the model trees. PIMS input database tables, however, are used in place of PIMS input spreadsheet tables when you convert from an input spreadsheet model to an input database model. PIMS-EE connects to this database and uses the data tables from this database as input data.
You can launch PIMS-EE from the Start | All Programs | AspenTech | Planning Version x.x.x | Aspen PIMS Enterprise Edition. Please referSolutions 126566, 115376 for the uses of PIMS-EE.
The new PIMS Output Database is SQL Server Database. As of version V7.3.0.3, you can send results to a SQL Server database or to both Access and SQL server. You can send to SQL by selecting SQL from the Database Type drop-down found on the General Model Settings dialog box.
Keywords: Environment variables
SQL
Sever
database
input
output
References: None |
Problem Statement: A system DSN has been created on the machine using AspenTech SQLplus ODBC driver. However when trying to import data using the DSN created in Microsoft Excel 2007, the following error is encountered: | Solution: The above error is encountered due to the use of the Data Connection Wizard. The Data Connection Wizard is for use with OLEDB provider. However SQLplus only has a ODBC provider. In order to import data from InfoPlus.21 successfully using the ODBC provider, Microsoft Query will have to be used instead.
To invoke Microsoft Query, do the following.
1. Click on the Data tab in the ribbon menu.
2. Click on From Other Sources.
3. Select From Microsoft Query from the context menu.
4. Select the System DSN created from the Choose Data Source dialog.
Keywords: The Data Connection Wizard cannot obtain a list of databases from the specified data source
References: None |
Problem Statement: What is the global token consumption of multiple InfoPlus.21 systems? For example, if you have 3 different Aspen InfoPlus.21 (IP.21) servers, one with 5,000 points (A), one with 700 points (B), one with 3,000 points (C), what is the total token consumption? | Solution: You have to consider each server separately. For example, if the token consumption indicated in the contract is 1 token per 4,000 IP.21 points, then the total consumption in the case indicated is:
A (2 tokens) + B (1 token) + C (1 token) = 4 tokens
The minimum token consumption for Aspen InfoPlus.21 is one token per server. The token consumption
for each server is calculated individually on the basis of 1 token per N points (N value written in the contract). The same applies for Aspen InfoPlus.21 Hot Backup System and Aspen InfoPlus.21 Development System on the basis of 1 token per M Points (M value written in the contract).
Keywords: Tokens
Token usage
IP21
SLM
Licensing
License
References: None |
Problem Statement: Sometimes, customers may want to insert new records into their InfoPlus.21 database from an ASCII file using SQLplus. One common problem which they could run into is that the database may not have enough free space to hold all the new records. With the help of SQLplus, it is relatively easy to estimate the availability of free space. A sample SQL script is provided below.
(AspenTech recommends 15% free space). | Solution: The following query determines how much free space is currently available, inserts one sample record, determines how much space it takes up, deletes it, then multiplies that amount of space times the number of records you want, and determines if there is enough free space available.
LOCAL NoofRec INTEGER;
LOCAL FreeSpaceBefore INTEGER;
LOCAL FreeSpaceAfter INTEGER;
LOCAL TotalDBSpaceBefore INTEGER;
LOCAL MemRequired REAL;
LOCAL recName CHARACTER(15);
write ''Current IP21 Database Size'';
write ''
Keywords: None
References: None |
Problem Statement: Is it possible to to start Aspen Process Explorer and pass a record name as an argument to create a plot/trend for it?
Customers often have many records in their Aspen InfoPlus.21 databases and want to avoid having to create multiple APX files for multiple records to plot/trend them. | Solution: We do not currently support generating a NEW trend plot from the command line.
The only way to open a trend plot from the command line is to create an APX file beforehand and then pass in the filename. For example, ProcessExplorer.exe MyPlotFile.apx.
Keywords: start argument plot
References: None |
Problem Statement: An Aspen Watch ODBC application (AspenWatch Maker or AspenWatch Inspector) is getting an error message with the text Network Failure or Incompatible SQLplus server ODBC--call failed.
This usually indicates that the client application has lost communication with the server application. This might be because the server application has stopped. It might have stopped and re-started, the client might have been running when the database was stopped and re-started and not reconnected to the database. | Solution: TheSolution is simply make sure the tsk_sql_server is running and then to disconnect and reconnect the client application, or dismiss and re-invoke the client application and allow it to connect again. This is usually under the file menu item
AspenWatch Maker has an icon for this (leftmost icon looks like a blue barrel with a lightning bolt.
AspenWatch Inspector requires that you create a new network connection (icon looks like a blank sheet of paper)
Keywords: None
References: None |
Problem Statement: What is the typical workflow to add new assays in Aspen Assay Manager? | Solution: New crudes will be added to existing Assay table with no change to existing assay data.
1. Open Assay Manager
2. Map and transfer data using Setup Wizard. No need to import existing data from PIMS
3. Click New Assay and select desired crude(s) from library
4. On “Buy” tab, set MIN, MAX, and COST valuesCharacterize the new assays
5. Generate Cutting Results
6. Update PIMS Tables
7. Exit Assay Manager
Keywords: Assay Manager
New Assays
References: None |
Problem Statement: At the end of run, Aspen PIMS pops up a window reading 'Html report failed! Exception has been thrown by the target of an invocation'. There is no | Solution: report generated. This happens sometimes when a user converts a multiperiod model to single period model.Solution
Try the following steps and see if the problem can be resolved.
1. Check if there is a file, called 'pimswin.exe.config' in the Aspen PIMS installation folder. If there is one, deleted, and try again running a model to see if the problem persists. This file forces Aspen PIMS to use .NET v 1.1; it was required in Aspen PIMS versions prior to 2004.1 (version 16)
2. Cleanup the model, delete 'mdb' file, exits Aspen PIMS, and starts Aspen PIMS again. Sometimes, a corrupt database may cause the problem.
3. If both 1 and 2 do not resolve issue, upgrade to 17.5.5 and higher since we have not seen any complains after then.
Refer toSolution 124589 for Aspen PIMS and .NET compatibility.
Keywords: Report
Failed
Html
.net
References: None |
Problem Statement: In the optimization problem, what is the difference in treatment of a constraint vs. a hard constraint? | Solution: The difference is only significant when the Optimiser has difficulty finding a feasible point. If it enters the minimise sum of squares phase, it has a choice of including violated constraints in the objective or of insisting that they should continue to be treated as constraints. Hard constraints never leave the constraint set, soft constraints can move into the minimum sum-of-squares objective on a temporary basis.
In a real-time, on-line situation, it is usually necessary to make sure that any open-equation constraints (those that are used to solve recycles, etc.) are treated in this way. Otherwise, theSolution may be meaningless and the intermediate results unusable! Process (or contract) constraints can often be violated on a temporary basis.
If you are running off-line, make as many as possible constraints soft.
Keywords: hard constraint
References: None |
Problem Statement: How to find the variables pump on and pump off for a pump operation in Aspen Simulation Workbook? | Solution: This variable needs to be searched in Aspen Simulation Workbook. The variable search tool In the Organizer can be activated by clicking the binocular icon(Shown below).
Then in the 'UniOps' folder, browse to find the variable from the drop down list:
The pump on/off switch variable can be found as shown below:
Keywords: pump on/off switch, variable search tool, ASW.
References: None |
Problem Statement: Aspen InfoPlus.21 2006.5 checks licensed points and throws an SLM_InfoPlous21_Point error message in Aspen Process Explorer and Aspen Administrator display. | Solution: Licesed points should be decreased to 500*SLM_InfoPlus.21_Points
Keywords: SLM_InfoPlus21_Points
References: None |
Problem Statement: How do I resolve the error message Error in setting new database size to nnnnnnn. Code = -82 when upgrading an Aspen InfoPlus.21 snapshot? | Solution: Open the Control Panel Services Applet. Make sure the 'Aspen InfoPlus.21 Task Service' is using a privileged Domain account. Then restart the service and retry the upgrade procedure.
Keywords:
References: None |
Problem Statement: When upgrading the Aspen InfoPlus.21 database, OEE records do not upgrade correctly and causes the upgrade to fail. | Solution: This occurs if upgrading a database that is V8.5 and older to a version of Aspen InfoPlus.21 that is V8.7 or newer and occurs because the oee.rld file was updated between V8.5 to V8.7 to have OEE_Def records renamed to OEEDef records. To work around this issue, rename OEE_Def in the older snapshot to OEEDef before performing the upgrade.
Keywords: OEEDef
OEE_Def
References: None |
Problem Statement: This | Solution: s provides an overview of different methods to read/write information from/to an Aspen InfoPlus.21 database from remote nodes. Further information about each method can be found on suggested knowledge baseSolutions or by contacting AspenTech technical support.
Solution
Aspen InfoPlus.21 provides three main methods to interact with external applications on remote nodes: an OPC-DA services, connection through ODBC, and an internal API. The next table provides an overview of this methods:
Method
Description
Read/Writes
Use
Other references
IP21 OPC DA service (IP21 OPC Data Access .NET Server Wrapper since V7.2)
This is an OPC DA interface based on .NET SDK provided by OPC Foundation. This service will communicate Aspen InfoPus.21 information using DCOM windows infrastructure, so that, it is possible to set up and manage security by DCOM settings. Information send through this service can be read by any OPC DA client or OPC interfaces. For more information regarding OPC-DA specification please visit OPC DA description in OPC Foundation webpage here.
Allow Read and Write
Use if you have an OPC-DA client needing to access Aspen InfoPlus.21 data.Solutions:
107985, 113756
Aspen SQLPlus ODBC driver
This option provides a method to access Aspen InfoPlus.21 information as it was a relational database. Every record will work as a table where fields in fixed area are used as data table column while Repeat area of a record is used also a table with the name of the record as title. Some applications like Access and Excel allows direct reads from ODBC sources. This method provides access to historical data.
Allow Read and Write
Use it if you’re familiar with SQL connections and scripts and/or need to retrieve a large amount of data efficiently.Solutions:
120486, 116533
IP.21 API (Application Programming Interface)
Allows the use of routines to interact with IP.21 database through the use of a library header file written for the C language.
Allow Read and Write
This could be a betterSolution if you want a custom application that fit a particular need, and you are familiar with writing application programs.Solution 140827
Keywords: IP.21
OPC-DA
SQLplus driver
IP.21 API
References: None |
Problem Statement: Launching the Aspen Tag Browser, the list of available servers is displayed correctly. When one of the servers is selected, an error is generated:
[AspenTech][SQLplus] Failed to connect to server. | Solution: If this behavior is exhibited even when Aspen Process Explorer is able to trend data normally, and the Aspen SQLplus client is able to access the Aspen InfoPlus.21 server successfully - then this is likely caused by a firewall setting. Resolve this by making sure that TagBrowser.exe is not blocked by the firewall.
Keywords: None
References: None |
Problem Statement: The yields coefficients for VBALAR1/WBALAR is doubled in matrix, i.e. the coefficients in the AR1 material balance is 2x the entry in the T.ASSAYS for the row VBALAR1/WBALAR1.
What is wrong? | Solution: When configure ATM bottom residue flow, there are two ways to achieve the same results. Take weight sample model as example,
1. With NEWCUT, but comment out WBALAR1
* TABLE
NEWCUT
Table of Contents
*
TEXT
CD1
CD2
CD3
***
*
LV1AR1
AR1 from LV1
1.00000
1.00000
1.00000
HV1AR1
AR1 from HV1
1.00000
1.00000
1.00000
VR1AR1
AR1 from VR1
1.00000
1.00000
1.00000
***
* TABLE
ASSAYS
Table of Contents
*
TEXT
ANS
AHV
ARL
BAC
IRL
KIR
KUW
MIN
NSF
TJL
***
*
*WBALAR1
Atm Resid 670+
0.58079
0.59119
0.47980
0.71601
0.47644
0.42799
0.48943
0.60037
0.44130
0.52659
WBALLV1
Lgt VGO 670-680F
0.03142
0.00782
0.01018
0.00969
0.00987
0.00926
0.00833
0.01050
0.00992
0.00866
WBALHV1
Hvy VGO 680-1050F
0.30477
0.25906
0.31876
0.31961
0.30877
0.25189
0.27413
0.36552
0.31196
0.29700
WBALVR1
Vac Resid 1050+
0.24460
0.32431
0.15086
0.38672
0.15780
0.16685
0.20697
0.22435
0.11942
0.22094
*
BALANCE CHECK
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
2. Suppress NEWCUT, use WBALAR1
* TABLE
ASSAYS
Table of Contents
*
TEXT
ANS
AHV
ARL
BAC
IRL
KIR
KUW
MIN
NSF
TJL
***
*
WBALAR1
Atm Resid 670+
0.58079
0.59119
0.47980
0.71601
0.47644
0.42799
0.48943
0.60037
0.44130
0.52659
WBALLV1
Lgt VGO 670-680F
0.03142
0.00782
0.01018
0.00969
0.00987
0.00926
0.00833
0.01050
0.00992
0.00866
WBALHV1
Hvy VGO 680-1050F
0.30477
0.25906
0.31876
0.31961
0.30877
0.25189
0.27413
0.36552
0.31196
0.29700
WBALVR1
Vac Resid 1050+
0.24460
0.32431
0.15086
0.38672
0.15780
0.16685
0.20697
0.22435
0.11942
0.22094
*
BALANCE CHECK
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
If both table NEWCUT and WBALAR1 present in the model, the yields will be double counted.
Keywords: NEWCUTS
Distillation
Yields
residual
WBALAR!
References: None |
Problem Statement: When mapping the timestamp for an InfoPlus.21 point in Process Graphics, there are no parameters to modify the timestamp formatting, is it possible to change? | Solution: The timestamp format used in Process Graphics is determined by your InfoPlus.21 timestamp format. In InfoPlus.21, the timestamp format is chosen in the Time Parameters tab, in Database Properties, from the InfoPlus.21 Administrator tool:
So it is possible to change the way timestamps are displayed in Process Graphics by changing the format for InfoPlus.21, but keep in mind this will affect the appearance of timestamps in other tools. Most importantly, if SQLplus scripts are written that expect a certain timestamp format, then changing the format could break those scripts, resulting in an invalid timestamp error. If changing the format is worth the effort, those scripts could be re-coded to handle timestamps independently of database format (see KB 102636.)
Keywords: Process Graphics Editor
Process Graphics Viewer
transform
References: None |
Problem Statement: The Aspen Process Explorer Excel Add-Ins introduced in version 7.3 require Microsoft Excel versions 2007 SP2 or 2010.
Normally, the Aspen Process Explorer Excel Add-Ins are installed when installing Aspen Process Explorer; however, if either Microsoft Excel is not installed on the client, or the wrong version of Excel is installed, the AspenTech installation procedure will not install the version 7.3 Excel Add-Ins.
This article explains how to install the Aspen Process Explorer Add-Ins introduced in version 7.3 after installing Microsoft Excel or upgrading Excel to a supported version on a client already running Aspen Process Explorer version 7.3 or later. | Solution: The Aspen Process Explorer Excel Add-Ins introduced with V7.3 are not Excel 'xla' add-ins as in previous versions of AspenTech's Excel Add-ins, but are instead COM Add-Ins found either in C:\Program Files\Common Files\AspenTech Shared\Excel\Addins or C:\Program Files(x86)\Common Files\AspenTech Shared\Excel\Addins.
After installing or upgrading Microsoft Excel to a supported version, it is not sufficient to copy the COM Add-Ins from one client to another. In order to install the version 7.3 Add-Ins you must after installing or upgrading Excel remove Aspen Process Explorer from the client machine, THEN REBOOT, and then reinstall Aspen Process Explorer.
NOTE:
Aspen Process Explorer Excel Add-Ins introduced with V7.3 require VSTO (Visual Studio Tools for Office 3.0) and VSTO SP1. VSTO and VSTO SP1 are installed when installing Aspen Process Explorer, and not when installing or upgrading Microsoft Excel. Performing an installation repair of Aspen Process Explorer does not install VSTO either.
If for some reason VSTO does not install, you can download VSTO 3.0 from
http://www.microsoft.com/download/en/details.aspx?id=23656
The VSTO 3.0 SP1 can be obtained at
http://www.microsoft.com/download/en/details.aspx?id=1132
Keywords: None
References: None |
Problem Statement: Aspen Process Explorer V7.3 Excel add-in does not load after upgrading from MS Office 2003 to MS Office 2007 or MS Office 2010. The Process Data Excel Legacy Excel Add-in was working properly in MS Office 2003. After MS Office was upgraded from version 2003 to version 2007/2010, the pre V7.3 and V7.3 add-ins do not work. | Solution: (For MS Office 2007/2010 32-bit only)
1. In V7.3, the use of Excel legacy Add-in requires the loading of the Excel v7.3 Add-in for it to function.
2. Close all MS and aspenONE applications.
3. Download and install the following components from the Microsoft website:
Microsoft Visual Studio Tools for the Microsoft Office system (version 3.0 Runtime) (x86)
Microsoft Visual Studio Tools for the Microsoft Office System (version 3.0 Runtime) Service Pack 1 (x86).
4. Register the AspenTech.PME.ExcelAddIn.ProcessData via the steps indicated in KB 134243
5. Once the registration is successful, open Excel.
6. You should be prompted to install the v7.3 VSTO Add-In component. Click <Ok> to proceed. You may be required to restart Excel.
7. Go to Excel COM Add-In and check on the AspenTech.PME.ExcelAddIn.ProcessData.
8. Once the COM Add-in is loaded successfully, you should see this in the Excel menu bar.
9. To enable the legacy Add-in, go to Excel Add-in and add Aspen Process Data Add-in - Legacy - V7.3 (2007)
10. Thereafter, you should be able to access the legacy add-in via the following:
Keywords: Excel Legacy Add-in, Excel V7.3 Add-in, Office 2007, Office 2010, compatibility
References: None |
Problem Statement: How can I get PIMS matrix intersections from the Results.MDB file? | Solution: The key table to get this information is the PrMpsCols table. This table, along with PrMpsRows, PrMpsRange, PrMpSRhs, are not always created. In order to get this information in V7.3, open the General Model Settings dialog (Model Settings | General). Choose the Output Database tab and then click the Options button to check the Output MpsBcd Database Data as shown in Figure. This will ensure getting PIMS matrix information in the Results.MDB file
In earlier versions of PIMS the option Output MpsBcd Database Data is on Model Settings | General | Output Database tab rather than clicking options
Keywords: Matrix from Results.MDB
Matrix for report writer
Row entries
Column entries
PIMS matrix
References: None |
Problem Statement: Aspen Process Explorer may crash when opening some graphic files. This is problem did not occur in versions prior to Aspen Process Explorer version V2006.5.
The problem is caused because a Process Graphic contains an image where the file attribute is empty when you view the image properties. | Solution: TheSolution is to open the graphic file in Aspen Process Graphics Editor 2006.5 or older version and add file attribute and then upgrade to V7.1.
Keywords: Process Explorer
Graphic Editor
crash
image
References: None |
Problem Statement: Aspen PIMS generates matrix before and after solving the model. How does Aspen PIMS name those files in PIMS-DR and PIMS-AO? | Solution: In PIMS-DR, Aspen PIMS will generate a model matrix file populated with the initial estimates of recursed properties from PGUESS and initializing error distribution depending on the number of distributed destination. This matrix file is called MPSPROB.MPS. At the end of the LPSolution, another matrix file is generated, called MPSBCD.MPS, which includes all theSolution values. If running multiple cases, the names will be MPSBCDxxx.MPS, where 'xxx' stands for that case number.
In PIMS-AO, there are two different methods to generate matrix. One uses XNLP while the other uses XLP.
1. The XNLP matrix generator generates MPSPROB.MPS with the initializing properties, then generates XMPS.MPS matrix with all the initial variables for the solver. PIMS solves the matrix and generates XMPS.XLP at the end ofSolution. Each case will generate aSolution matrix, called MPSBCDxxx.MPS.
2. The XLP matrix generator generates XLP_NEW.XLP, PIMS then solves the matrix and generates XMPSxxx.XLP for each case'sSolution matrix.
Keywords: PIMS-DR
PIMS-AO
Matrix Analysis
References: None |
Problem Statement: How to switch to Dual mode in Aspen PIMS? | Solution: To run Pims in the Dual mode, goto LP settings-->Options-->Select Dual instead of Primal.
Keywords: Dual Mode
LP settings
References: None |
Problem Statement: What does “Update PIMS tables� in Assay Manager change in Aspen PIMS? | Solution: After generating cutting results, “Update PIMS Tables� can be clicked to:
1. Send data back to PIMS tables
· Table BUY updated with MIN, MAX, COST
· Table CRDDISTL updated with EST-row
· Table ASSAYS updated with data for new crude(s)
2. Rename and suppress original PIMS Excel input files
3. Create New file with same file name as original and attach to the model tree
Once the PIMS model is updated, it can be run using the new crude data
Keywords: Assay Manager
Update PIMS table
References: None |
Problem Statement: With multiple installations of Aspen HYSYS or Aspen Plus with Exchanger Design and Rating, EDR will be called from the last version. Running an Aspen HYSYS file with EDR exchanger embedded in old version, doesn't solve exchanger. | Solution: To register desired version of EDR to HYSYS or Aspen plus, go to below directory:
C:\Program Files\AspenTech\Aspen Exchanger Design and Rating Vx.x\XEQ
then run the file BJACVC.exe, below screen will pop up:
Then check the box Register Aspen Exchanger Design & Rating version with Aspen Plus and HYSYS and click on Set.
Keywords: None
References: None |
Problem Statement: What are compositions of the liquid and vapor phase inside the vessel during and after depressurization? | Solution: Liquid and vapor compositions in the vessel are same as liquid out and vapor out compositions at the corresponding time. The compositions of the left over liquid and vapor inside vessel after blow-down are equal to the corresponding liquid out and vapor out compositions of the last moment of the depressurization.
Note that Aspen HYSYS reports liquid out compositions even liquid out flow rate is zero.
Keywords: composition, left out, remaining, vapor, liquid, blowdown, blow-down, depressuring, depressurization
References: None |
Problem Statement: How do I determine the sequence of unit calculations? | Solution: 1) In the CONFIG Table set DEBUGINFOLVEL to 0
2) In CONFIG Table set TIMR to Y, if TIMR row is not present create one
3) Now simulate all
4) A file named ORION.CSV will be created in the Local Working Directory
5) This ORION.CSV file will list sequence of unit calculations (this will have only user defined unit and crude units)
Keywords: Sequence of unit calculation
Unit sequence
Units
References: None |
Problem Statement: In a PID controller, what is the intent of the Range PV Min/Max? What is the purpose of the PV limits in Parameters tab | Advanced section? Should these be left empty? | Solution: The PV Range section purpose is just to define the minimum and maximum limits that the controller can measure. In real life, controllers are built with a particular range of measure, and this is the information necessary in this section. In fact, the Face Plate window takes this range so you can define the Set Point between these limits (the range the controller can measure).
For example, in the next image, the PV range is between 0 and 9e5 lb/h. So, in the Face Plate you can measure/define the flow through the valve (Set Point) between 0 and 9e5 lb/h
It’s important to notice that the controller cannot switch from Off mode unless PVmin and PVmax are defined.
Now, in Parameters tab | Advanced Section | Limit Setting you can set the targets for the Set Point, Operation Point and Process Variable.
In the same example, The PV range is 0 – 9e5 lb/h. You can specify that the SP range is from 0 – 8e5 lb/h. Now, with this specification, you can define the SP only up to 8e5 lb/h although the controller can measure up to 9e5 lb/h.
The face plate will re-locate the Set Point in 8e5 lb/h if you specify a bigger number for the SP.
The same applied for the OP. In this example the OP is the Actuator Desire Position. So the OP limits is between completely close and completely open. You can specify the limit position of the actuator in this section.
For the PV limits, this allows the user to see small PV overshoots just outside of the PV range. However, internally the controller algorithm only sees the PV varying within the PV range. So for example a 2% change in PV from 102% to 104% of the range will not affect the controller output.
So, the PV min/max does not affect directly the OP%. You’re limiting independently both parameters to represent and study the behavior of your system.
This should not be left empty (the model simple won’t run because of this information is missing), but HYSYS automatically fills these cells; you can customize it if you want as needed to evaluate the system.
Keywords: PID controller, PV Range, Limit Settings, Face plate
References: None |
Problem Statement: What are the high level inputs and outputs of APS | Solution: The following are the high-level inputs/outputs of Aspen Petroleum Scheduler
Inputs:
Model Configuration: Tanks, Units, Pipelines, Unit Feeds and Yields
Logic: How process units function, what volumes and qualities are calculated and how
Schedule: Events are scheduled (movements/unit operations/blends)
Outputs:
Tank/Stream Inventory and Qualities;
Unit Operating Parameters/Conditions;
Refinery Wide Schedule
Static Inputs: Model Configuration, Logic
Dynamic Inputs: Tank data, Events
Keywords: None
References: None |
Problem Statement: In economic evaluations for the refinery planning process, it is necessary to have a clear picture of the impact of adding incremental amounts of a material, either as a feed or as a product.
Useful information for analysis include the Break Even value of the material, the change in the Objective Function as the amount of material changes, and the Marginal Cost and Marginal Revenue curves.
The typical business process to get this information is to set up a series of Cases in Aspen PIMS, in which the the amount of the material to be evaluated is increased in steps.
With the output information from PIMS (e.g. CaseComparison.xls report), the necessary calculations can be done. No automated process is provided by Aspen PIMS to run the calculations.
How can it be automated? | Solution: The attached Report Writer Template automates the following calculations:
? Break Even value for every increment of material analyzed (i.e. total increment vs. base case)
Marginal Cost and Marginal Revenue Curves
Objective Function changes vs. volume of material analyzed.
Attached are also two sample databases with case data for streams ANS (Purchase) and UPR (Sale) that you can use to test this application. It also includes the final reports created with it.
Note: For a description of the Marginal Cost and Revenue curves, please seeSolution 124689.
Set up of the Cases in Aspen PIMS
In Aspen PIMS, set up a series of Cases changing the amount of the Feedstock (Table BUY), or the Product (Table SELL).
Use fixed COST or PRICE, change the quantities only (force MIN and MAX to the same value).
A minimum of five cases is recommended to provide more granularity for the Marginal Cost and Marginal Revenue curves.
Use of the report
Note: You need to have Aspen Report Writer installed in your machine to use this report. Starting with Aspen PIMS 2006 it comes included in the standard license.
? Copy the attached Report Writer Template (.xlt file) to the model folder.
Open Excel, go to the Report Writer ?AspenRpt? menu and select Run.
Browse to the model folder and select the template.
You will be prompted to write the 3-character Tag of the stream that you are evaluating, and to indicate whether the material is a Purchase or a Sale (as the data required for the calculations are stored in different tables).
? Once you click OK, you will be prompted to select the Results.mdb, if it is not the right one, browse to the intended database.
Results
The final report will list the relevant information from the Cases in tabular form, as well as in graphs for the Marginal Cost and Revenue Curves, the Objective Function and the Break Even (for this curve, the Break Even at each point is calculated for the total quantity up to that point, i.e. Current Case vs. First Case).
Below is an example for product UPR. A similar report is generated for a feedstock.
Limitations of the report
It will report in Volume only (even in weight based models), and for the first period only if using a multiperiod model.
If you select a stream tag that has not been changed in the cases, or if you select the incorrect option (Purchase or Sale) the information and the graphs coming out will be meaningless.
Keywords: ort Writer
Break Even
BreakEven
Marginal Value
DJ
Rep
References: None |
Problem Statement: What troubleshooting steps are available if a client application cannot connect to an available Aspen Data Source Architecture server? | Solution: Use the following steps to confirm that clients machines are able to access the ADSA server.
1. Confirm that the ADSA data source has been configured correctly. Consult the Adding a Public Data Source entry in the ADSA help files for additional information on required components for various data sources.
2. Check the services files (%systemroot%\system32\drivers\etc) to verify that the port numbers are not duplicated by other services. Also confirm that the the port numbers are consistent between machines. For example, the default port for TSK_SQL_SERVER in Aspen InfoPlus.21 is 10014. This port number (10014) should also be specified in the properties menu for the Aspen SQLplus service component in the ADSA Client Config Tool.
3. Using the ADSA client tool, you can click on the Test button to check the connection between the client application and server. If the connection is unsuccessful, the ADSA Client Config Tool will generate the following error:
A Remote activation was necessary but the server name provided was invalid (Unable to resolve server hostname to IP address.
If this message is received, confirm that the ADSA client is able to ping (from a command window) the ADSA server by IP address and by nodename.
Also confirm that the ADSA client is able to perform a successful nslookup (from a command window) on the ADSA server's name and IP address.
4. The following error may also be generated when attempting to connect to the ADSA server:
This computer was unable to communicate with the computer providing the server.
Choose the Web Service protocol if there is a firewall between clients and the ADSA Directory Server. Use of the Web Service protocol will eliminate DCOM issues related to firewalls.
5. For additional client connection information, it is possible to enable client application ADSA logging. Attempted connections to the ADSA server are recorded when this feature is enabled. To enable logging there is a choice of methods depending on your version of MES client tools. When using version 8.8 and above, ADSA logging control can be found in the Process Data Administrator – before v8.8 this was done using a separate registry setting.
i. With MES version 8.8 and above, open the Process Data Administrator:
%ProgramFiles(x86)%\AspenTech\ProcessData\ProcessDataAdministrator.exe for 32-bit process logging
%ProgramFiles%\AspenTech\MES\ProcessData\ProcessDataAdministrator.exe for 64-bit process logging,
Then select the Logging tab and enable the Steps logging for the ADSA Locator component.
Diagnostics log will then be generated and can be found in:
%ProgramData%\AspenTech\DiagnosticLogs\SharedComponents\
Note, make sure you turn off all logging once you have finished your investigation.
ii. With MES version 8.7 and below:
Go to: Start | Run | regedit.exe
For 64-bit process logging, navigate to HKEY_LOCAL_MACHINE\SOFTWARE\AspenTech\ADSA
Under this key create a new key named Log.
Double-click on default and specify the path and log file. When the key is exported, it should be of the following form:
[HKEY_LOCAL_MACHINE\SOFTWARE\AspenTech\ADSA\Log] @=c:\\atadsa.log
Note, for 32-bit process logging you should instead make the above changes under the following key:
HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\AspenTech\ADSANote, for 32-bit process
Keywords: ADSA
connection
performance
data source
service
References: None |
Problem Statement: What are the high level inputs and outputs of APS | Solution: The following are the high-level inputs/outputs of Aspen Petroleum Scheduler
Inputs:
Model Configuration: Tanks, Units, Pipelines, Unit Feeds and Yields
Logic: How process units function, what volumes and qualities are calculated and how
Schedule: Events are scheduled (movements/unit operations/blends)
Outputs:
Tank/Stream Inventory and Qualities;
Unit Operating Parameters/Conditions;
Refinery Wide Schedule
Static Inputs: Model Configuration, Logic
Dynamic Inputs: Tank data, Events
Keywords: None
References: None |
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