question stringlengths 19 6.88k | answer stringlengths 38 33.3k |
|---|---|
Problem Statement: Why is the molar flow of the 'pseudo stream' not reported properly in a calculator block when selecting P-Mole-Flow? | Solution: P-Mole-Flow as can be observed in the screenshot below. It is described as the molar flow rate of a pseudo product stream. It could be understood as a block result, however, P-Mole-Flow is the input molar flow rate of a pseudo product stream which can be found in the calculator block specification as Block-Va... |
Problem Statement: When I copy the MULDIP viscosity parameters for a databank component of a user defined component, the viscosity reported for the components is very different. | Solution: If you specify components and then retrieve parameters for them then Aspen Plus/ Aspen Properties will show the parameters including the method parameters for the thermodynamic (THRSWT) and transport (TRNSWT) models which tell which equation will be used to calculate properties.
Based on this information, u... |
Problem Statement: In RadFrac itself a user has two different ways to select a property method. One is in the Specification| Block option folder. The second place where the user can select the property method for segments, reboiler and condenser is Specification| Properties folder. Given the various methods, which meth... | Solution: If the user specified the property method for a section of the column in the Specification | Properties folder, that method will override the default property method for this section of the column. For example, if the user specified SRK for stages 2 to 5 in the Specification | Properties folder, then SRK will... |
Problem Statement: What's New in Aspen Plus V7.3 - Start page with news feed | Solution: Aspen Plus V7.3 makes it easier than ever to stay informed with news about upcoming webinars, training events, how-to knowledgebase articles, and short animated tutorials. The new Start Page features quick links to help topics, including a summary of new features of Aspen Plus V7.3 and previous versions. Ther... |
Problem Statement: Are Options/Preferences being saved in Template file? | Solution: Batch Plus users can create a new Project based on a saved Template. Options are being saved in Template file along with other data (equipment, materials, mixtures, utilities, reactions, cells, packaging materials, equipment pools, and preferences) of the Project on which the template is saved. Many users imp... |
Problem Statement: How to customize the language used in the Batch Plus Recipe Text? | Solution: Language templates are stored in Access database. Go to Preferences\Language\Setup User Templates. Select or specify a directory to store the new template files. Click Copy to create the templates. They will begin with the name User (for example UserEnglish.lng).
Use MS Access to open and edit these files whe... |
Problem Statement: After a 'Load Column' operation, the final volume of the column is greater than the capacity of the column. Why is that? | Solution: The column fill factor defines the amount of 'free space' in the column. If the fill factor is equal to one (default), all the column capacity is available to the liquid material. The material which is retained in the resin will be considered as additional volume. Hence, if some material is retained in the co... |
Problem Statement: Currently any custom Fortran shared libraries that support User Models, User Properties, User Physical Property models etc. require a DLOPT file that points to the location of the supporting dll's. Sometimes this is confusing to new users and is often overlooked. A more efficient way of including est... | Solution: The user/administrator can specify a default DLOPT file by adding a line like
DLOPT: ${ASPTOP}\xeq\InhDlopt.opt
(the name specified is arbitrary) into the %asptop%\xeq\aspfiles.def. The specified DLOPT file will be used by Aspen Plus runs unless the user explicitly specified a DLOPT file.
This mechanism... |
Problem Statement: Is it possible to specify multiple feed compositions within a production plan? The production plan includes several batches with varying recycle stream composition or feeds compostion (ie the feed compositions change with each new batch). | Solution: It is possible to do this by using the Start Or ..Series ...End Or
Keywords: within the recipe.
To do this:
Highlight the text recipe you want the OR keyword to be inserted before or after .
Note:
The Keyword can be inserted before or after the text. The deafult is to insert after. To change the default, clic... |
Problem Statement: Why are there inconsistent results between PC-SAFT and POLYPCSF?
PC-SAFT is a new and the better option, so we are migrating from POLYPCSF; however, PC-SAFT is giving different, wrong answers. | Solution: A possible causes for the inconsistent results between PC-SAFT and POLYPCSF is that both PC-SAFT and CPIG parameters for the polymer are entered (instead of its segment) when using PC-SAFT.
In the Online Help for PC-SAFT, there is the following description regarding the parameter input for PC-SAFT:
Since ... |
Problem Statement: How does Aspen Polymer Plus handles solubility as function of polymer molecule weights? | Solution: Polymers Plus provides two types of property models: segment-based and component-based. The segment-based models such as POLYNRTL and PC-SAFT have already taken into account the changes due to the polymer molecular weight. The model parameters are defined for segments that can be used to construct a polymer a... |
Problem Statement: Aspen Plus V7.3.2 will not start after applying Emergency Patch 1 (EP1) | Solution: Here is how you can resolve the problem.
Log off the system and login with a privileged account
Try to run Aspen Plus V7.3.2, if you are able to run the application then do as follows:
Rename the profile of the user who is not able to run the program. Here is how you can rename the profile:
Open windows brows... |
Problem Statement: Simulation that ran without problem in a previous release now fails during the report generation. | Solution: The errors occur in the report pass, not during the simulation. Turn off Aspen Dynamics. From Tools | Options | Startup, uncheck Aspen Plus Dynamics under enable forms for layered products. Aspen Dynamics requires some additional calculations, and these are triggering the errors.
Keywords: None
References: : ... |
Problem Statement: Is it possible to have the files that are imported and exported use a different working folder than files that are saved and/or opened? | Solution: It is not possible to set this in Aspen Plus. However, one can add a shortcut to a folder in the Favorites folder. Then, this folder can be reached easily by clicking on the Favorites button when importing or exporting. The user needs to be an Administrator to add the new shortcut.
Keywords: None
References: ... |
Problem Statement: When two different polymers are formed in one reactor at the same time, it is not possible to look at the Molecular weight distribution of each polymer separately. I need to get the molecular weight distribution (MWD) of each polymer not the sum of both. | Solution: Polymers need to be separated in order to get separate MWD for each polymer. For this purpose, a separator (Sep) block can be used. Attached file which uses the library example ldpe.bkp demonstrates the above methodology.
Keywords: Polymers, Molecular weight distribution.
References: None |
Problem Statement: If you go in Aspen Plus v7.2 under Components |Specifications on the Enterprise Database tab, only pure component data bank selection is available.
In V7.1 you could select pure component databanks and binary parameter databanks separately.
From Tools, Options, the Component Data tab allows both ... | Solution: If you uncheck the option Retrieve binary and pair parameters automatically in the GUI, then you can select the binary parameter databanks under Components, Specifications, Entreprise database. This option prevents duplicating the parameters in the GUI (e.g. if the databank is updated, the simulation will use... |
Problem Statement: Presence of Double quotes ('') in the Setup | Specifications | Description will give the following error message:
** ERROR IN A DESCRIPTION PARAGRAPH
SKW: DESCRIPTION
INVALID USE OF POSITIONAL NOTATION.
THE SENTENCE AS ENTERED WOULD ASSIGN THE VALUE:
QUOTES TO TERTIARY KEYWORD NUMBER 2.
HOWEVER, TH... | Solution: Double quote () have not been allowed in the description since 2006.5. Single quote (') are allowed. If the file is saved using 2006.5 or earlier, delete the double quote () from the description. You will not be able to re-enter it.
Keywords: FOR THIS SENTENCE. SENTENCE IGNORED.
References: : CQ00432897 |
Problem Statement: What's New in Aspen Plus V7.3? | Solution: Aspen Plus V7.3 includes many new and improved features to help you save time and effort developing new conceptual designs, evaluate relative capital and operating costs for alternative process schemes, improve the energy efficiency of your processes, and examine the carbon footprint of proposed designs.
Ther... |
Problem Statement: Unable to get results message when trying to issue Excel reports.
The Excel templates shipped with Batch Plus 2.1 are compatible with Microsoft Excel 95, 97 and 2000. The problem is that the three different versions of Excel have conflicting references to DAO (Data Access Object).
The templates shipp... | Solution: The patch contains new Batch Plus 2.1 templates which explicitly reference the version of DAO compatible with Microsoft Excel 97 and 2000 only.
The enclosed self-extractable file contains 53 new templates. The new templates replace the existing templates present in C:\Program Files\AspenTech\Batch Plus 2.1\Te... |
Problem Statement: Is it possible to embed an Aspen Plus *.bkp file in a Microsoft Word document? | Solution: To embed a bkp file in word document (or any Microsoft Office application) do the following:
1. In Microsoft Word click on the Insert | Object then you will get the following Object Window:
2. Click on the Browse button and locate the bkp file as shown below:
3. Click OK and then bkp fil... |
Problem Statement: How does one take a second liquid from RadFrac? | Solution: RadFrac can handle two liquid phases along with a vapor phase in the column. There is an example file called 3phase.bkp in the Favorites | Applications directory of Aspen Plus that has an example that uses a side stream attached to a decanter in a column. SeeSolution 115269.
To remove one or a mixture of the ... |
Problem Statement: I cannot perform a regression because I am getting an error of a required parameter is missing, what can I do? | Solution: If you are conducting some property analysis together with your regression run, calculations will stop at input specifications if the routes involved in the calculation of the properties are incomplete, that is, all the required parameters for the routes are not available. When performing analysis, in order t... |
Problem Statement: What is the meaning of the abbreviations that appear in the zone profiles tab of MHeatX block? | Solution: In the context of a pinch point you can have either a local or global pinch point and this are the abbreviations
GBL = GLOBAL
LOC = LOCAL
The Streams/Phases column is used to indicate whether a stream is at its dew or bubble point, or whether it enters or leaves the exchanger at that location. The abbreviat... |
Problem Statement: Is it possible to use CALUPP in a user property set subroutine? Sometimes it works ok, but sometimes there are strange results. | Solution: CALUPP should not be called from user property subroutines. Doing so may result in recursive function calls which may overwrite variables (such as those in Common blocks) used in the first call, which that call may still need. This will lead to unpredictable results.
Extensive use of Common blocks in Aspen ... |
Problem Statement: Aspen Plus Compound file folder user defined contents are removed when the Aspen Plus file is closed. | Solution: Aspen Plus Compound file format apwz includes the Heat Exchangers, ads and apw file. Any files manually placed inside the folder would not be stored once the apwz file is closed.
User defined files can be stored in apwz file format from the Aspen Plus -> File -> Edit Compound File -> Embed new files. The embe... |
Problem Statement: How to make the OLI database available to Aspen Plus when working with compound files (apwz). | Solution: The apwz is a compress file type that puts together all the input data, simulation results, and any other external files that the simulation may require. When you open the compound file (apwz), a temporary folder is created in the working directory with the unpacked contents and other temporary files. If you ... |
Problem Statement: I would like to have a table with stream results in Excel which does update automatically when the simulation is complete. This can be done with Aspen Simulation Workbook but the selection of the streams is very tedious. | Solution: There is now a Model Summary feature in Aspen Plus V8.6 which can be used to complete this task. The attached document highlight the steps you can follow to generate such a table (the instructions look long, but it's really only a few mouse clicks).
Steps to export the stream results to Excel with ASW links... |
Problem Statement: Selecting edit/insert/time stamp from Aspen Plus flow sheet menu and clicking anywhere on the flow sheet produces garbage. Which registry is used to fetch the pertinent information from? | Solution: Selecting Tools/options will open the following window:
The information within the Time Stamp.. gets displayed when you Select edit/insert/time stamp. If these information are not correct or you want to change them then Clicking on the Time Stamp.. option will display the following window:
Remove all ... |
Problem Statement: New Feature in Aspen Plus V7.2 - Molecular Structure Editor | Solution: Aspen Plus V7.2 includes a new tool to draw molecular structure
You can open the molecule editor:
Within the User-Defined Component Wizard
From the Properties | Molecular Structure | Structure sheet
From the Tools menu or the toolbar button
This tool allows you to draw the structure of a molecule in order to... |
Problem Statement: Is it possible to display the version, file name, date and time created in the flowsheet? | Solution: It is possible to display the version, file name, date and time created in the flowsheet. To add this information in the flowsheet, execute the following steps:
1. Click on the A button for adding a text box to the flowsheet. The A button is on the far left of the Draw toolbar in the Process Flowsheet Win... |
Problem Statement: Is there a comparative list available for incorporated features in Aspen Plus versions of V7.2, V7.3, V7.3.2, V8.0, V8.2 and V8.4? | Solution: There had been updates in terms of Operating systems, Databank components and Additional tools among various versions of Aspen Plus.
Here are the major segments updated:
Operating Systems: Supported Operating Systems and Supported MS Office Versions
Databank: Pure components and Mixture Systems
Additional Too... |
Problem Statement: Aspen plus로3개 이상 성분들의 공비점을 계산할 수 있는가? | Solution: 계산할 수 있다. Aspen plus는 Aspen Distillation Synthesis 라고 하는 기능으로 3개 이상의 성분들의 공비점을 계산할 수 있다. 조성성분들을 모두 입력한 후, 물성방법을 NRTL로 선정한다.
그리고, Tools | Conceptual Design | Azeotrope Search를 선택한다.
Azeptrope Analysis 입력창에서 원하는 성분들을 임의로 선택한 후, Report를 클릭하면 공비점 결과들을 볼 수 있다.
참고로, Aspen split이라고 하는 라이센스가 있어야 한다.
Please ... |
Problem Statement: Where are the Run Settings in Aspen Plus V7.3.2? They used to be found on the Run menu. | Solution: To enter Run Settings, go to the small arrow at the lower right corner of the Run section of the Home ribbon.
They are also found from the Options button on the Developer ribbon.
Keywords: None
References: None |
Problem Statement: Why doesn't Aspen Plus predict the correct adiabatic flame temperature for methane or propane in pure oxygen? | Solution: An RGibbs block can be used to predict the adiabatic flame temperature; however, this value may not be correct if trace components are not specified on the Components | Specification form so that they are available as possible products. If the combustion products are restricted to complete combustion, the adi... |
Problem Statement: What are the differences between HappLS, IHapp, HappAprop, HappIP, HappAPropIP types? | Solution: HappLS represents the COM class component (coclass name), or in other words, it contains the executable implementation of a COM object (dll or exe) and its instantiation constitutes the server. HappLS implements IHapp along with some other interfaces. HappAprop is the coclass name for Aspen Properties standal... |
Problem Statement: After opening the Aspen Plus Simulation Engine Window there is a message, The system cannot find the path specified. None of the Aspen Plus commands such as aspen, aspcomp, makeins, or strlib work.
The Simulation Engine Window is shown below:
Cause
The paths are not set properly most likely due to ... | Solution: To correct this problem you need to go to C:\Program Files\AspenTech\Aspen Plus Vx.x\Engine\Xeq\ or C:\Program Files (x86)\AspenTech\Aspen Plus Vx.x\Engine\Xeq\ if it is a 64bit system, make a copy of the aspsetup.bat file and edit it, it will be like this where asptop, aprsys, and oomftop are blank:
You ... |
Problem Statement: How do you turn off the automatic block or stream naming so that you do not start with default names for blocks and streams? | Solution: In Aspen Plus, when a new block/stream is inserted, it is automatically assigned a prefix B/S. If however, it is intended to provide a logical name to the block/stream without having it initially named with BXX/SXX, the user can uncheck the naming option as shown in the screenshot. The flowsheet Display Optio... |
Problem Statement: FAQs for Issues and scope of modeling Inverse emulsion Polymerization in Aspen Polymer | Solution: 1) Is there an appropriate way to model inverse emulsion polymerizations, where a water-soluble monomer is emulsified in an oil phase? Or does model only work when continuous phase is water and monomer is immiscible with water?
The system allows you to specify a dispersant component. Usually this is water. ... |
Problem Statement: Where is the blue Next button in Aspen Plus V7.3.2? Did AspenTech get rid of this very useful feature? | Solution: The Next button functionality is still available, however, the button looks a bit different. The Next button is now green . It is located in the Run section of the Home ribbon plus it is on the Quick Access tool bar at the very top of the Aspen Plus User Interface window.
Keywords: navigation, user interface,... |
Problem Statement: In RadFrac, a user can specify distillate flowrate or bottom flowrate. When there is a need to access the specification in a Calculator block or sensitivity analysis, what is the internal variable to select? | Solution: A user opens the Variable Definition dialog, or the Vary datasheet (in sensitivity analysis).
The Type field should be Block-Var. The Variable field should be MOLE-D for distillate mole flowrate, MASS-D for distillate mass flowrate, STDVOL-D for distillate standard liquid volume flowrate, and MOLE-B for botto... |
Problem Statement: 여러 버전의 Aspen Hysys가 설치되어 있을 경우, default버전을 어떻게 설정하는가? | Solution: Aspen Hysys는 Excel automation work을 연동하여 모사할 수 있다. 만약 한 컴퓨터에 여러버전의 Aspen Hysys가 설치되어 있을 경우엔 default Aspen Hysys버전설정이 필요하다. Aspen Hysys는 별첨한 스크립트파일을 이용하여 간단하게 원하는 버전을 등록 혹은 해제할 수 있다.
1. RegHYSYS72.txt파일을 다운로드한다.
2. RegHYSYS72.txt확장자명을 RegHYSYS72.bat로 바꾼다.
3. 더블클릭하면 모든 Aspen Hysys버전들이 해제됨과 동시... |
Problem Statement: Scrubbers cannot be selected in batch operations, such as Utilize and Custom. They do not appear in the dropdown list. | Solution: Scrubber is a continuous equipment type, so it cannot be selected for batch operations. In fact, any equipment of a continuous type cannot be selected for batch operations; it can be selected for continuous operations only.
Keywords:
References: None |
Problem Statement: What is the syntax if I need to split a format string (or any string) in a OOMF (equation oriented) script?
I've tried this:
SET FMT = %-15s \
%-15.3f \n
PRINT FORMATTED &FMT, hello, 123
but it does not work. | Solution: The correct syntax is as follows:
SET FMT = %-15s \
. %-15.3f \n
PRINT FORMATTED &FMT, hello, 123
The reason is that when you don't close a string, the syntax is ambiguous and Aspen Plus does not use the backslash (continuation character) as such, it just sees it as part of the string, which causes a syntax e... |
Problem Statement: Simulation with RadFrac column (Scrubber) diverges when using true component electrolyte approach with the following error message:
*** SEVERE ERRORCMBAL CALCULATIONS FAILURE: RERUN WITH CHANGES SUGGESTED IF THERE ARE ANY.
The above error is produced for different reasons, however in this case it is ... | Solution: ThisSolution provides a recommended workaround by changing the electrolyte simulation approach to apparent component under the Electrolyte Wizard (Properties Environment):
Having set this modification, go to the Simulation environment and restart/re-run the simulation. The error message will be gone and the s... |
Problem Statement: A user will often need to create Ternary diagrams using the distillation synthesis button in the Simulation Environment in Aspen Plus and they would like to know how Aspen Plus calculates distillation boundaries that are drawn within this diagram. | Solution: In order to have a background about ternary map and distillation boundaries, the user can find this under the Aspen Plus Online Help in the chapter: Locating Azeotropes and Distillation Region Boundaries. In this description the user can find general information about residue curves, azeotropes and how distil... |
Problem Statement: How can the Fill Volume reported in Emission Details be different from the volume reported in Equipment Contents? | Solution: Fill Volume reported in Emission Details is the total volume of liquids and solids that enter an equipment unit in an operation. This will be equal to the total volume of all the streams going to this vessel for the operation. Emission calculations use the total amount of material that enters an equipment uni... |
Problem Statement: 用Aspen plus可以计算三个以上混合物的共沸点吗？ | Solution: 可以的。Aspen plus里有个功能叫做Aspen Distillation Synthesis.用它来可以轻松地计算三个以上混合物的共沸点。首先，输入混合物组分。
接着选NRTL为物性方法和激活 Tools | Conceptual Design | Azeotrope Search.
然后，在Azeotrope Analysis 输入栏里指定要测试的组分。点Report 会看见被Aspen Plus计算出来的共沸点结果值。
要是运行此功能必须有Aspen Split license.
Please find theSolution 133389 for the original Engl... |
Problem Statement: Why can't I see the predefined cells from the cell pulldown in an operation? In the CELL-DISRUPT/Optional/Cell Disruption form, the newly predefined cells do not show up. | Solution: The reason is that the defined cells are not selected for the step yet. The cells will appear in the dropdown list after they are selected for the step in the Step/(Information/) Optional/Cells form. Batch Plus allows up to 2 kinds of cells in each step.
Keywords: cell-disrupt
predefined cells
step
batch plus... |
Problem Statement: Is it possible to specify percentage of the equilibrium conversion at a given temperature do this kind of specification for a reactor? | Solution: There is not a direct way to specify a percentage of equilibrium conversion in any type of reactor. The issue is that the conversion at equilibrium for a given temperature is unknown.
With the help of a REquil block it is possible to obtain the conversion at equilibrium and a Calculator block it is used to ... |
Problem Statement: Is it possible to specify that a certain percentage of QC Tests fail and that the recipe takes a different course with the product from failed QC tests? | Solution: To specify that a certain percentage of Quality Control (QC) tests fail and that recipes with failures take a different course, one could use the Start Or/End Or structure in a Batch Plus recipe. The Start Or function is used as a step within a plan to specify parallel operations or unit procedures that happe... |
Problem Statement: What does it mean when I uncheck Components with zero flow or fraction on the Setup | Report Options | Stream sheet? I do not see a difference in the graphical user interface. | Solution: If you uncheck Components with zero flow or fraction, when you export or view the text stream report, it will be generated with no streams with zero flow or fraction.This only applies to the .REP report file and not to the stream report in the graphical user interface.
If you want to exclude components in t... |
Problem Statement: On Windows 7 and Windows Server 2008, you may encounter difficulties and failures with aspenONE deployment:
1. When installing/uninstalling aspenONE engineering products.
2. When using certain features. | Solution: The problem in most cases has something to do with the fact that you did not run your task as ?administrator?. Windows 7 and Windows Server 2008 enforce a stricter policy regarding user privileges than we were used to under XP. In Win 7, only tasks running with Administrative privileges are permitted to chang... |
Problem Statement: In RPlug model I see that 'Heat duty' reported in the Results | Summary is different from the summation of duties reported in Profiles | Summary | Duty. Why is there a difference in the duties obtained? | Solution: The difference in heat duty values in the RPlug Profiles page and in the RPlug Results page can be explained based on the stream conditions and the reactor operating conditions. Thus, if the feed stream temperature and the Rplug temperature is same, then the last value of the 'Duty' in the Profiles | Summary ... |
Problem Statement: When you save a compound file (.bpz) in Aspen Batch Process Developer, files with extension .prj (project), .eqm (equipment), .mtl (material), .stp (step) are also saved in the project working directory. How can I save the file such that ONLY a compound file (.bpz) is saved? | Solution: By modifying the Aspen Batch Process Developer registry settings one can save file only as compound file (.bpz).
Navigate to the registry location: HKEY_CURRENT_USER\Software\AspenTech\Batch Plus\version number\Batch Plus\Options. Create a new DWORD type registry entry called SaveOnlyAsCompoundFile and set th... |
Problem Statement: In reactions such as Step-Growth, it is necessary to add end elements with one active group and nonactive group, to stop chain from growing. How is it possible to specify this element? | Solution: The steps are as follows:
Categorize the chain stopper as Segment in Components/Specifications form.
Define the chain stopper segment as END type on the Components/Polymers/Characterization form.
If the chain stopper segment is not a databank component, define the van Krevelen functional group on the Proper... |
Problem Statement: Can a user add new equipment to the Equipment Catalog? | Solution: No. Users can't add equipment to the Equipment Catalog.
KeyWaords:
Keywords: None
References: None |
Problem Statement: Often liquid mixture and pure component densities may be different, even though the mixture is 100% pure. This occurs when a different equation is used to calculate pure component and mixture liquid molar volume. Refer to | Solution: 3261 Why are the Mixture and Pure Property liquid densities different?
The workaround provided inSolution 3261 is to change the model for property VLMX from VLMX01 or VLMX20 to VLMX26, so that the mixture molar volume is calculated from a mole-fraction average of the pure component molar volume.
However, if y... |
Problem Statement: How do I simulate polyurethane processes using Aspen Polymers? | Solution: Polyurethanes are a family of polymers produced by pseudocondensation reactions involving diisocyanates. They are characterized by the presence of urethane (~NHCOO~) groups in the polymer backbone. These materials are used to produce adhesives, engineering plastics, and foam sheets.
Segmentation
Aspen Polym... |
Problem Statement: It is sometimes required to carry out a detailed design of the re-boiler or the condenser of the Radfrac distillation column.
Based on KB #130085, it is possible to create a pseudo stream in the Radfrac block to represent the mixture properties present in the re-boiler or the condenser. This pseudo s... | Solution: The calculated duty values from the Radfrac block re-boiler can be transferred to the input of the HX block by using a transfer block.
The transfer blocks can be found in the flowsheet option folder. In the attached example file, in the “From� tab the Block-Var variable REB-Duty has been selected (see the... |
Problem Statement: What is the meaning of color code status in the fields in Aspen Plus V7.3.2? | Solution:
Keywords: color code, color status
References: None |
Problem Statement: When copying to Excel, how do you get everything expanded in the Stream Summary? | Solution: If you click the upper left cell in the table, you will copy what is shown. If the flows are not expanded, they will not be copied. If you click Export to Excel in the Report section of the stream summary ribbon, you will export a table with everything expanded.
Keywords: V9 new stream summary
References: : C... |
Problem Statement: What is the difference between expansion through a VALVE and expansion through a COMPR? | Solution: In summary, a VALVE performs an isenthalpic expansion whereas a COMPR performs an isentropic expansion. Both processes are assumed to be adiabatic. By definition, an isenthalpic process is a special case of an adiabatic process that does no work and is irreversible, and an isentropic process is a special case... |
Problem Statement: In V8.0, there is no longer a Block Options form for RadFrac in order to change the property method or to select if results from the previous pass are used. | Solution: The Block Options form exists for all blocks. For RadFrac, the form still exists only it has been moved into the RadFrac | Specifications folder. The forms for RadFrac were re-organized into folders since there were so many of them it was getting unwieldy. Only the results forms are now at the top level.
Keyw... |
Problem Statement: In the Aspen Plus built-in example (Biodiesel Production from Vegetable Oil), why do I see NaOH, H3PO4 and Na3PO4 are all defined as H2O in the component list? | Solution: In this special example, Sodium hydroxide is used as the catalyst, and is removed by adding H3PO4 to precipitate Na3PO4. Because electrolyte chemistry is not modeled in detail, these electrolytes are modeled using physical property data for water, but with their correct molecular weights.
User can find the co... |
Problem Statement: The parameter KLL2 is listed as one of the thermodynamic properties available in Aspen Plus for components in mixtures. It is described as the Liquid-liquid K-value for a component in a mixture. While it gives the user information concerning the equilibrium between two liquid phases, it should not be... | Solution: 142955 for information on the latter).Solution
Parameter definition
The KLL2 parameter corresponds to the distribution coefficient and is available directly from Aspen Plus for components in a given system under certain conditions. For an activity coefficient-based model, it is defined as:
where and are the... |
Problem Statement: In Aspen Plus when one is creating a default utility from the ‘Utilities’ folder in the Simulation Environment, there is not enough information about the different utilities available and their specifications to be used in the simulation’s models. Hence, one wonders what are the physical properties, ... | Solution: In order to illustrate comprehensively these characteristics of the different utilities available in Aspen Plus, the table below provides comprehensive and useful information about the specifications and conditions of these utilities:
Table No. 1: Utilities specifications and conditions templates used by Aspe... |
Problem Statement: When retrieving data from Aspen Plus using Excel VBA to following error might be displayed.
Microsoft Office Excel is waiting for another application to complete and OLE action. | Solution: This problem could happen when a simulation takes a long time to converge. Excel may think that Aspen Plus is not responding and hence issue the message.
Please add the following code to avoid Excel doing this:
Application.DisplayAlerts = False
Keywords: VBA
Excel
Visula Basic
OLE action
References: None |
Problem Statement: What method is being used in the Flash2 block? The help mentions the Inside-Out algorithm.
Do you have the literature reference? | Solution: Flash2 uses the flash convergence algorithm specified on the Setup | Calculation Options | Flash Convergence sheet, or on the the block's Block Options | Simulation Options sheet.
Setup | Calculation Options | Flash Convergence sheet:
Block options | Simulation Options:
The available methods are Ins... |
Problem Statement: The following warning appears while using Aspen Rate-Based Distillation:
UNUSUAL (type) PROFILE FOR COMP (component id).
PLEASE DOUBLE CHECK THE | Solution: AND/OR ADJUST FLOW MODEL,
TRANSFER/REACTION CONDITION NUMBERS, PACKING HEIGHT/NSTAGE, ...
Type may be LIQUID MOLEFRAC, LIQUID INTERFACE MOLEFRAC, COMPONENT GENERATION, INTERFACE MASS TRANSFER, or INTERFACE HEAT TRANSFER, the last of these without a component ID.
Solution
This can be caused by poor choices for... |
Problem Statement: How do I select and specify the convergence method in Aspen Plus? | Solution: In Aspen Plus, we have the ability to use different convergence methods. The available methods are as follows:
Wegstein Method: Wegstein method is used for tear streams and it is the default method for Aspen Plus tear stream convergence.It has different, adjustable, parameters such as acceleration parameter ,... |
Problem Statement: Why are there no message prompts at the bottom of forms in V7.3.2? | Solution: The message prompts were replaced by the pop-up tool tips. If you prefer the prompts, go to the View tab and select Message Panel from the Show section of the ribbon.
Keywords: user interface, tool tips, notifications, menus, message prompts
References: None |
Problem Statement: What is the property method for steam and cooling water utilities? | Solution: Physical properties are needed to determine the heating value for utilities when you select the Specify inlet/outlet conditions option on the Specifications sheet. The answer to this question is on the Properties sheet of the Utility block. Steam and Water utilities use the global free-water property method... |
Problem Statement: How to retrieve and use the attribute completion status of a node | Solution: In order to retrieve the attribute completion status of a node, you should use the AttributeValue(attrnumber) method of an IHNode, where the argument is an enumerated value from the HAPAttributeNumber, in this case HAP_COMPSTATUS.
The value of the completion status attribute can be used for bitwise comparison... |
Problem Statement: How can I use in Aspen Plus the property method Peng Robinson with enthalpies calculated by Lee-Kesler method? | Solution: There are no property methods in Aspen Plus/Aspen Properties that include this option by default. To use this combination, the calculation route has to be modified. In order to use the Peng-Robinson equation for the fugacity calculations but the Lee-Kesler model for enthalpy and additionally for Gibbs free en... |
Problem Statement: I am using supplementary stream report with a user written routine. In the user interface, the report is not generated, however, when I run an input file in the simulation engine, it does generate the user report file. In V7.3, the report file is generated when the results are written. | Solution: The supplementary stream report is generated when you export a report (.rep) file since the report is only in the text report file and not on the user interface forms. In earlier versions, it was generated during the user interface report calculations.
Keywords: None
References: None |
Problem Statement: How can I create a dump file? | Solution: To create a dump file please follow the steps:
Step 1
Open your Aspen Plus and run your simulation
Step 2
Load the task manager in your machine
Step 3
Right click on the process (Aspen Plus) and then select Create dump file.
A dialogue box will tell you in which folder the dump file will be saved.
Keywords: D... |
Problem Statement: In a DSTWU block, why is the user not allowed to specify a heavy key component recovery that is higher than the light key component recovery? | Solution: In a DSTWU block, recovery always refers to distillate recovery. It is equal to the mole flow of the component in the distillate divided by the mole flow of the component in the feed. This convention applies to both light and heavy key recoveries. Thus, the recovery of the heavy key component cannot be greate... |
Problem Statement: I want to include mass transfer in my RPLUG model, how can I do it? | Solution: In the RPLUG block model you can specify user subroutine parameters for kinetics, heat transfer, pressure drop, but there is no direct way to specify a subroutine for the mass transfer.
What you can do is to define a subroutine for reaction kinetics that consider the mass transfer in its parameters if these f... |
Problem Statement: How do I find application simulation examples delivered with Aspen Plus V7.3.2? | Solution: Click on the Examples icon on the Get Started ribbon to go to the directory of simple and complex examples shipped with Aspen Plus.
There are a wide range of examples from rate-based amine columns to ammonia to biodiesel to coal to polymers along with the files associated with the Getting Started manuals.... |
Problem Statement: I want to add an NQ Curve to my column. However, the button to add it isn't enabled. Why is this and how can I enable it? | Solution: To add NQ Curves, there must be a design specification related to each of the product streams of the column. So if for example, you have a column with a bottoms product, liquid and vapor distillate products, you will need three design specifications in order to enable the NQ Curves. Before adding these, the N... |
Problem Statement: The file name is shown on the screen in an almost invisible color combination (dark gray on black?). Is it possible to change the color so the file name is readily visible, e.g. White on black. | Solution: The color of the top bar, which contains the file name, depends on the background (desktop or any other app) where its placed. For example, if your desktop is blue, the file name would appear darker. If the desktop is light background, the colors are better visible.
Font size and color used for the window t... |
Problem Statement: Automation in Aspen Plus: How to change the value of a variable in the units specified by the user with the Unit Table. | Solution: The unit table consists of rows representing physical quantities and columns representing the units of measurement in which the quantities can be expressed. It can be found in the variable explorer immediately under the root node (see picture below).
The following code will let you change the value of a varia... |
Problem Statement: In an electrolyte system I am getting densities for streams significantly lower than experimental data, what could be the problem? | Solution: If you selected H+ as hydrogen ion type, the inconsistency in the density results you are noticing are probably caused by this selection indeed. When you use H+, the mass density is computed from the MW of the apparent H+ instead from the real hydronium ion. Hence the difference. Please use the H3O+ approach ... |
Problem Statement: For piping calculations I need to get a stream with the flow coming out of the condenser of a RadFrac block. The pseudo stream to return the liquid flow on stage 1 actually gives the liquid flow going to stage 2, which is excluding the distillate. How can I define a stream with the flow of both disti... | Solution: This information is not available in the pseudo stream of RadFrac, but you can easily work around this limitation using a calculator block. The attached file illustrates for Aspen Plus V7.3 how this can be done.
The calculator block C-1 imports the liquid flowrate (molar) from the RadFrac block for stage 1. P... |
Problem Statement: What is the Aspen Remote Simulation Service? | Solution: Aspen Remote Simulation Service (ARSS) is a component that provides a remote execution environment for other AspenTech tools including Aspen Simulation Workbook and Aspen Model Deployment.
ARSS allows model developers to deploy models onto a server accessible to several client computers.
AspenTech simulation ... |
Problem Statement: When adding pure water in a stream at 1 atm and 25 C using H2O dissociation chemistry, why doesn´t the dissociation composition correspond to the 1e-7 constants value? The dissociation shows concentrations of 1e-10 kmol/hr. | Solution: The dissociation displayed for the stream results are molar flows and not molar concentrations (mol/l). If you add a property set to report the dissociation concentrations, you will see the correct values.
The property that needs to be added to a property set is MOLECONC with units in mol/l.
This property... |
Problem Statement: Is it possible to use polymers in the solid unit operation models? | Solution: Before V8.8, Component Type “Polymer” was not supported in Solid handling models. Polymer pellets could be defined under “Solid” type. If you use MIXCISLD streams and put the polymer in the CISOLID substream, Aspen Plus will ignore phase equilibrium involving the polymer. CISOLID polymers are treated as cryst... |
Problem Statement: How to hide and reveal a design specification and other objects through Automation Server in Aspen Plus. | Solution: A design specification sets the value of a variable that Aspen Plus would otherwise calculate. For example, you may want to specify a product stream purity or the permissible amount of an impurity in a recycle stream.
When using Automation code, you might want to activate or deactivate design specification or... |
Problem Statement: My question is related to the selection of the mass transfer correlation that can yield results with some confidence to go forward to vendors for final design. The Stichlmair constants for the Super Raschig Rings are not defaulted and when trying to compare correlations some significant differences ... | Solution: This is a very difficult topic to discuss. There are a many mass transfer correlations available for packings. Aspen Plus includes a selection of the more popular and successful ones. However, one cannot depend on any given mass transfer correlation to give quantitative design results for a specific packing t... |
Problem Statement: What are typical friction parameters for solid particles for materials to specify within the Aspen Plus Pipe dilute solid conveying option? | Solution: The following chart shows typical sliding friction factors (Fluid friction parameters) and particle size for various solid materials in the dilute phase.
Solid Material
Particle Size
[μm]
Coefficient of sliding friction f
Against aluminum
Against stainless steel
Against steel
ABS Powder (Butadiene)
30. ... |
Problem Statement: What are typical Conveyance values in Dilute phase for pipes in Solids Conveying? | Solution: The chart below proposes several operating values in different suspended flows (Dilute Phase).
Solid / Fluid velocity ratio is the average particle velocity divided by the average divided by the average axial velocity of a gas. Furthermore you will find values for Load Ratio, Mean particle size of feed, aver... |
Problem Statement: In Aspen Plus and Aspen HYSYS from version V8.0, the user has the option to use aspenONE Exchange to search for examples from the knowledge base. These files may be downloaded and accessed from within the application as shown below:
After the file has been downloaded, a window prompts to open the fi... | Solution: All files downloaded using aspenONE Exchange are available when you open the Exchange window in Aspen Plus and there you can find in the 'My Downloads' section where Aspenplus has saved the history for all downloaded items. The screenshot below illustrates this.
Here you can just click on the title, downloa... |
Problem Statement: What is the difference between “RES-TIME (overall residence time)” and “phase residence time” when specifying a RCSTR? | Solution: In RCSTR, when you have multiple phases, you can specify RES-TIME (overall residence time) or phase residence time.
When you specify residence time, the reactor assumes no-slip conditions between the phases. This implies the vapor fraction in the reactor is the same as in the mixed outlet stream. Since the mo... |
Problem Statement: Why are the global data not showing anymore on my PFD? | Solution: There are actually three places controlling the display of Global Data:
Settings on Tools | Options | Results View where
Setting for View | Global Data where the display of the selected stream variables can be activated or de-activated globally
Setting for the background context menu | Hide Labels where if a ... |
Problem Statement: When using the option of size independent growth described by McCabe’s law of growth in a Crystallizer model in Aspen Plus and this is not providing similar results to the PSD seeds added plus a size independent increase, as the below formula states:
Where:
R... | Solution: According to the McCabe’s law above, the w_i is the fraction in the number distribution. That is how we obtain one delta_L valid for all particles. The picture below shows how we then redistribute the particles on the existing size bins. The wider the size bins (low number of intervals) the bigger the numer... |
Problem Statement: How to get heat curve data from a Thermal and phase state changer model (For example: Heater). The data will include vapor and liquid phase properties like Density, viscosity, heat capacity, surface tension etc. | Solution: Please follow the steps:
1. Complete the input section of the model
2. Create a new HCurve file (H Curves > New)
3. In the SetuP form, chose number of data points (Set Up > Number of data points)
4. Select desired property sets (Additional Properties > select and transfer from Available to Selected Property ... |
Problem Statement: In rate-based MEA model to simulate a CO2 absorber/stripper combination, how are MEA chemistry block Keq's calculated? | Solution: Aspen Plus has the ability to calculate the equilibrium of ions / apparent components using Gibbs free energy. If there are parameters for the equation for the equilibrium constant for a particular reaction on the Equilibrium sheet on the REACTIONS | CHEMISTRY | GLOBAL form, it will have a higher priority. Bu... |
Problem Statement: Converged RadFrac distillation column simulation appears to be out of Enthalpy Balance. | Solution: The Aspen Plus RadFrac distillation column block report summarizes the heat and material balance. The mass and enegy balance results are shown on the RadFrac | Results | Balance sheet.
These Converged RadFrac results often have a very small (less than 1E-10) relative mass/mole difference between inlet and out... |
Problem Statement: I am using an equation of state method, but I have been able to report the activity coefficient (gamma) for the stream using a property set. There is no activity coefficient model used in the simulation. What is being calculated? | Solution: We calculate the activity coefficient (gamma) from fugacity coefficients. For activity coefficient (gamma) models such as NRTL, the property gamma simply came from the model itself. For equation of state (EOS) models such as PR, we would calculate gamma from fugacity coefficients. Note that for the equation o... |
Problem Statement: How to solve the following error:
SEVERE ERROR
ERROR DURING DYNAMIC LINK OF USER ROUTINE(S) OR IN-LINE FORTRAN
PLEASE CHECK FILE _3347vfr.ld FOR LINKER MESSAGES.
*** SEVERE ERROR
COULD NOT RESOLVE USER OR IN-LINE FORTRAN SUBROUTINE(S):
SUBROUTINE USRSTR IS MISSING | Solution: This is a linker error that indicates that a user subroutine is active in your simulation and the binary file with the subroutine couldn't be found by the linker during symbol reSolution. By the subroutine's name we can infer that it is a stream report subroutine in this case. In order to solve this, we have ... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.