question stringlengths 19 6.88k | answer stringlengths 38 33.3k |
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Problem Statement: Table CRDDIST is used to define the structure of theoretical or logical crude units. Row ESTxxx in table CRDDIST is to configure the possible crude feeds to particular crude units. Any non-blank numerical number in the intersection of row ESTxxx with column crude unit indicates the feed xxx is allowe... | Solution: Let?s look at a typical feed configuration in Table CRDDIST (only shown partial of table CRDDIST),
* TABLE
CRDDISTL
Table of Contents
*
Crude Distillation Map
TEXT
CD1
CD2
CD3
***
*
*
Crude Type ->
SWEET
SOUR
SOUR
*
*
Operating Mode ->
Fuels
Fuels
Lube
*
Feed
ESTA... |
Problem Statement: You get an error or warning message highlighting that UBALXYZ is not a row name, where XYZ is a utility tag.
This error or warning does not come from Aspen PIMS but rather from the Optimizer, after the matrix has already been created.
What is causing this and how can you solve it?
Note: using the X... | Solution: The message appears because the utility XYZ is declared in table CRDDISTL but it has not been declared in table UTILBUY.
TheSolution is to either remove it from table CRDISTL, or add it to table UTILBUY as a purchase.
If this is an internally generated utility (i.e. not purchased), you still need to declare i... |
Problem Statement: We are using PBONUS in our PIMS model and have found it to be a good way to have PIMS blending recipes close to the actual ones without adding aditional complexity to our models. We have also found that we need to change PBONUS coefficients when switching between summer and winter blending. Now we wo... | Solution: Table PBONUS was never designed with period specific entries in mind. We are considering the introduction of this in a future release of AO. If one would like to use period specific blending bonus values the best way is to create own user defined structure in place of PBONUS. In this example we will show only... |
Problem Statement: How do I prevent Global Optimization from failing when using Convex Relaxation? | Solution: Global Optimization using Convex Relaxation is only suitable for models whose only non-linearities are either bi- or tri- linear terms. Any external non-linearities like ABML, RFG gasoline, Table CURVE/NONLIN, etc. make a model unsuitable for use with Convex Relaxation. If you try to use this feature with... |
Problem Statement: When using CRDTANKS / CRDALLOC to implement crude tanks logic, PIMS automatically creates alias tag for each crude stream involved in the Crude De-Pooling structure, for example for Alaskan N Slope (ANS) - an1. Description of the new stream is also created automatically and by default is: Crude Strea... | Solution: You can add an EST row in T.CRDDISTL with a crude alias tag and input a description in the TEXT column. This way you will replace the automatically generated description both in Crude Unit and De-Pooling submodel reports. Please note that you do not have to provide mapping input as it will be generated automa... |
Problem Statement: When setting up a pooling structure to recurse some properties of the pool, usually -999 are used as placeholders for the RprpPol rows.
This is possible as long as the yield coefficient of the components is -1, which is typically the case in a feed pool.
However when the yield coefficient of the pool... | Solution: There are two ways of handling this situation:
Use explicitly Yield Coefficient * Property Values in the recursion rows.
Create an additional structure to allow the use of -999 by creating -1 Yield Coefficients.
Both methods are highlighted below, in an example of two Product Pools, PR1 and PR2. There are t... |
Problem Statement: In table CRDCUTS, swing cuts are defined as type 4 cuts. By default, they have two destinations, up and down to combine with the adjacent streams.
Can swing cuts also be explicitly produced in the crude units and consumed downstream? | Solution: Swing cuts can be consumed downstream. The only thing that you need to do is provide a destination, which could be in a submodel, in blending or in sales. Those destinations are defined by adding the appropiate entries to the corresponding tables as for any other stream.
For example, if swing cut HN1 can go t... |
Problem Statement: My network is very slow, especially when I am on the road, what is the best way to configure the license? | Solution: You can use Aspen 'SLM Commute License' tool to check out the license so it acts as a standalone license. This eliminates the need for a network connection when running Aspen products.
From Start | All Programs | AspenTech | Common Utilities | SLM Commute,
Select the necessary license you need to checkou... |
Problem Statement: How do I detect if RPENALTY is being used from the ExecutionLog file? | Solution: Compare the following two partial log from ExecutionLog.lst file. Before PIMS start solving the problem, it shows a section as 'Problem Statistics' in the ExecutionLog file. When there is no RPENALTY used, the problem should be close to be square, which means the number in 'Row' and the number in 'Structural ... |
Problem Statement: Where can I find a list of properties that can be defined in Aspen Assay Manager? Can the units for these properties be different? | Solution: The user can find the list of available properties that can be used in assay manager in Libraries branch on the model tree.
Once you select a property the units of measure can be chosen from various dropdowns in the system. The user can have different units of measure and can mix the units. For eg. The user c... |
Problem Statement: ABML (Aspen Blend Model Library) provides a portfolio of pre-defined linear and non-linear blending prediction methods and correlations.
The ABML portfolio can be expanded by adding user defined correlations using the following ABML functions:
GBLNVAL
GNDXR
GPRPCALC
UBML (User Blending Model Library)... | Solution: In this example, we will model the properties G15 and G59, defined as follows:
G15 = T50-T10
G59 = T90-T50
The following steps are required:
1. Add the formulas to the Property Calculation Formula
In the Aspen PIMS Model Tree go to the Property Calculation Formula facility, and add the new Calculations as i... |
Problem Statement: How to use 'USER TOOLS MENU' to copy Aspen PIMS files from one model directory to another? | Solution: First create a batch file using Notepad. In this example, the file is called xcopy.bat. There is one line in xcopy.bat as follows:
XCOPY/S/Y * d:\volume sample
Where:
/S Copies directories and subdirectories except empty ones.
/Y Suppresses prompting to confirm if want to overwrite an existing destination f... |
Problem Statement: How are 999 and -999 placeholders handled in the data validation stage in PIMS AO and PIMS DR? | Solution: In PIMS DR, for the validation stage, the placeholders are handled in the following manner.
1. For 999 placeholders, the values are updated from the Pguess table
2. For -999 placeholders, the values are updated from BLNPROP, ASSAY, BUY, and PCALC tables
3. If PIMS cannot get a value for the placeh... |
Problem Statement: How to disable a property (quality) variable from the PIMS model | Solution: Sometimes users would like to disable a specific quality variable in the PIMS model because they are no longer using/tracking this in the model. Leaving the structure in the model may cause PIMS to take more recursion passes to solve. In order to disable a quality, the rows and columns associated with this qu... |
Problem Statement: If I have created a VPRICE structure for a blended product and it does not have SPG values for one of the components, will Aspen PIMS convert the API property values to SPG for getting Weight to Volume conversion? | Solution: PIMS-AO will automatically consider the API values and convert these values to SPG in order to get the necessary VPRICE structure working. However, PIMS-DR needs to be provided with SPG values in the BLNPROP tables for all the components in order to get the right objective function when using VPRICE structu... |
Problem Statement: How do I link one of the provided PowerPivot templates to my SQL database? | Solution: Templates for PIMS Analytics are provided with a typical PIMS installation. These templates are located in a folder called Analytics in the same location as the PIMS sample models. These templates can be used with your own SQL database to provide an example of the reporting that can be done using the automati... |
Problem Statement: Can I use base delta structure for yields that vary depending on the percentage of atmospheric residues in FCC. | Solution: Tables where you would add the structure: Feed Pool submodel, FCC submodel, SCALE, PGUESS, and BLNPROP.
I took these tables from the Volume Sample Model. Note that the ?important? changes are marked in the yellow cells.
In my case, the name of the Atmospheric Residue stream is ?ATB? and the Atmospheric Residu... |
Problem Statement: How to use the Submodel Calculator (SMC) in Aspen PIMS global models | Solution: The Submodel Calculator feature is not enabled in Aspen MPIMS or XPIMS because the main model that is open is the global model, which does not have any submodels. The submodels to be evaluated with the Submodel Calculator belong to the local models.
Open one of the local models of the XPIMS structure and run ... |
Problem Statement: This | Solution: demonstrates how to build a discrete yield submodel in PIMS.Solution
Use the submodel tables to construct and link process submodels that represent different process units in a plant. Subject only to a minimal set of restrictions, the submodels can be constructed to be as simple or complex as necessary. Submo... |
Problem Statement: How can I model quality dependent unit capacities? | Solution: Some situations may require the unit capacities to be dependent on quality of the feedstock. In this case, the model is to be modified in such a way that PIMS generates a coefficient in the capacity row that can reflect the quality of the feed of the unit
Consider the following example
Assume we need to chang... |
Problem Statement: How do I control total transfers in an M-PIMS model? | Solution: Inter-plant transfers in an M-PIMS model can be controlled by creating an L-Row or a CCAP-Row in the global Table ROWS. If a CCAP-row is used, the limits and activities corresponding to this row will be reported in FullSolution report.
In this example the transfer from plant C to plant A is controlled
* TABL... |
Problem Statement: When physical crude units are specified in the ATMTWR row of Table CRDDISTL, Aspen PIMS automatically generates a capacity for each physical unit. These are called CCAPAT1, CCAPAT2, etc. If I have more than 10 physical crude units, how are those after #9 named? | Solution: Aspen PIMS allows up to 50 physical crude units. Below is a chart showing the physical crude number and the corresponding capacity name.
1
CCAPAT1
2
CCAPAT2
3
CCAPAT3
4
CCAPAT4
5
CCAPAT5
6
CCAPAT6
7
CCAPAT7
8
CCAPAT8
9
CCAPAT9
10
CCAPAT:
11
CCAPAT;
12
CCAPAT<
13
CCAPAT=
14
CCAPAT>
15
CCAPAT?
16
CCAPAT@
17
C... |
Problem Statement: What are the matrix row and column names for an MPIMS model'? | Solution: The matrix column and row names for a standard PIMS model are 7-characters in length. For an MPIMS matrix, the name have 8 characters. The 8th character is typically the local plant ID.
The global model has some additional tables that are not part of a standard PIMS model. These include MODELS, MODES, MARKETS... |
Problem Statement: Assuming we are using Property Calculation Formulas to calculate index RVI from property RVP, can we see RVI for a stream in a given submodel using a reporting rows (Prows)? | Solution: It depends. Lets say, a submodel has input streams A, and B, whose RVP are known (and their RVI supposed to be calculated from the property formula). The output stream is C, and and you want to report its RVI using report row.
In this case, you will have problem because PIMS does not have any RVI information ... |
Problem Statement: Upon investigation of Material Sales section of Full | Solution: Report it turned out that some sold products have incorrect aggregate value. Please refer to the example below:
If the same is calculated manually then the result is different:
346 Units/DAY * 73.180 $/Unit = 25,320 $/DAY
Where does this difference come from?Solution
As you can see HSF pricing is volume basis... |
Problem Statement: A user is trying to commute an Aspen PIMS license, but it is asking for an Administrator user name and password. Does the user need an Administrator right to commute the Aspen License? | Solution: SLM Commute V7.3 needs the Administrator right to run. In SLM V8, we removed the administrator privilege requirement. You can use the Aspen 'SLM License Configuration Wizard' then click button 'Config' to check what SLM version you have.
Please see the SLM Version 2012.0.1.304 or above, which is SLM V8.0.... |
Problem Statement: The California Air Board updated the Amended CARB3 equations at the end of September, 2008. How can these changes be incorporated into PIMS, ORION, and MBO? | Solution: ABML version 1.7.43 contains the correction to the amended CARB3 spreadsheet that CARB posted toward the end of September 2008. The change will affect winter gasoline grades that have oxygenate in them. The main impact is in the potency weighted toxics.
The ABML.dll file attached to thisSolution incorporate... |
Problem Statement: When users select SQL server as output database, execute Aspen PIMS, PIMS will generate the report in the SQL PIMS database. Now open platinum to generate the flowsheet, why platinum does not generate a flowsheet from the active model? | Solution: When this happens, check if you have different models saved in the same database.
You can check from the table PrModel , by right click 'PrModel', then 'Select Top 1000 Rows'. Check to see how many models you have written into this database.
If you have more than one model there, you may have a problem. PIMS... |
Problem Statement: How can I model a stream that can be either sent to the crude unit or sent directly downstream to blending -- for example a purchased kerosene stream? | Solution: Attached is an example demonstrating this. In this model stream zzz can go directly to SCD1 or to blending into product ZZZ. The steps include:
1) Setup stream zzz in Table ASSAYS. In this example the yield is specified as 100% kerosene. Populate the properties as completely as possible.
2) Add row ESTzzz... |
Problem Statement: When running my model with Multi-Start, I get the following error:
Html Report Failed! There is an inconsistency in the result database!
What can I do to solve it? | Solution: Do a Model Cleanup. On the Execution dialog box, select the Access Database Maintenance option of Only Unique Cases, instead of Purge Existing.
Also, turn off any unneeded database options under MODEL SETTINGS | GENERAL | Output Database tab, click on OPTIONS.
Keywords: multistart
stacked cases
References: No... |
Problem Statement: When I load the PIMS model, I am unable to see any tables in the model tree. How can I get the excel files on the model tree? | Solution: After Installing Aspen PIMS it might happen that the user loads a model and is unable to see any Excel files attached to the model tree. This might be either a PIMS issue or an excel issue. When this happens the user can try the following two approaches:
1. Try to follow the steps given inSolution ID 1365... |
Problem Statement: What rules are to be followed for pool segregation of Crude cut types? | Solution: The following rules are to be followed for the pool segregation of different types of crude cuts
1. All Type-2 cuts must be segregated
2. All Type-4 cuts must be segregated
3. Segregated pools can be combined through user defined sub-model tables
4. Type-3 cuts are not required to be segregate... |
Problem Statement: How do I identify very large or very small coefficients in the matrix? | Solution: It is important to eliminate very large and very small coefficients in the matrix because these can cause convergence problems. In general we recommend that coefficients are not above 1e+7 or below 1e-7. There is a tool available in the Matrix Analyzer that can identify coefficients that are outside your ... |
Problem Statement: How do I temporarily worsen my yields without recalculating all the assays? E.g. experiencing temporary increase in Vacuum Residue yields or just wanting to make a sensitivity in an investment study without too much effort. | Solution: Table SWING gives an excellent way for quick crude unit yields adjustments. For those not familiar with it: it is a quick way of sending a certain portion of one stream into another. This affects not just the material balance but also all of the qualities are recalculated. Downside is that for the quality cal... |
Problem Statement: The properties of yield stream are calculated by Recursion in the Base-Delta submodel without using PCALC.
How do I calculate the coefficients for the Recursion in Base-Delta submodel? | Solution: Below is an explanation of the calculation using a simple example.
BAS is a Base vector, SUL is a Delta vector.
Recursion Matrix (suppose Error vector is zero)
BAS
SUL
PRD
RHS
RBALPRD
-a
-b
1
=0
RSULPRD
-c
-d
f
=0
We need to calculate the coefficient d
from RSULPRD
-c*BAS -d*SUL +f*PRD =0
d*SUL = f*PR... |
Problem Statement: When trying to run Assay Manager I get following error messages and application crashes:
There is already a listener on IP endopint... This could happen if there is another application already listening on this endopint or if you have multiple service endpoints in your service host with the same IP e... | Solution: Go to Windows Services, right click on Aspen Enterprise Logging Server and select Stop:
Assay Manager should run properly now.
Keywords: There is already a listener on IP endpoint
Assay Manager
error
References: None |
Problem Statement: Can Impose Nonzero Pool Flows and Fix Quality of zero flow pools to initial values be used at the same time? | Solution: This is not recommended. The Impose Nonzero Pool Flows solver setting can potentially conflict with the Fix Quality of zero flow pools to initial values XSLP solver setting. These settings aim to address the same issue and should not be used together.
Keywords:
References: None |
Problem Statement: There are sometimes questions about the sign convention of the PI values (shadow prices or marginal values) of the Rows, specifically for the Capacity (CCAP) and Material Balance (WBAL, VBAL) Rows.
Intuition indicates that the sign of the PI value should be positive when the Row Activity hits a MAX (... | Solution: 1. The mathematically correct definition of the shadow prices or PI values on the rows are the marginal values on the slack variables of each row. That is, they are the Dual Activities of the DualSolution.
The sign on them is consistent with the PIMS sign convention:
· Costs are negative
· ... |
Problem Statement: What causes unable to write error when running Case Comparison? | Solution: To avoid this issue, turn on the Use Excel to createSolution spreadsheets in current Excel format option. This is located under MODEL SETTINGS | Reporting | Miscellaneous.
NOTE that some users may not see the Unable to Write message and may instead get this dialog in Excel as it is trying to generate the C... |
Problem Statement: 如何解决当PIMS运行Excel自动化时所得到的server busy信息? | Solution: 当Excel自动化运行缓慢时， server busy的信息会显现。这有可能是Excel add-ins，错误的Excel公式或数据读取问题等等所导致的。在补丁Aspen PIMS V8.7 CP7中针对这个问题添加修补程序。您可以从以下这个链接下载补丁：http://support.aspentech.com/webteamcgi/SolutionDisplay_view.cgi?key=143447
如果您未能安装补丁或必须使用V8.7 CP7之前的PIMS版本，请参考以下要点以加速Excel自动化的运行：
· 尽量减少使用Excel add-ins
· 尽量减少在Aspen ... |
Problem Statement: In the Pr | Solution: table of the database there is a field “Description” where a description of theSolutionID can be found. How can you specify this description of theSolutionID such that this field in the database is filled?
Solution
The Description column entry in the PrSolution table comes from the model execution dialog box ... |
Problem Statement: In the Scenario Evaluation Tool, for Override, Selection, and Parametric scenarios I see there are two columns: Activity and MarginalValue. What are these for and how do I get them populated? | Solution: These columns show the base caseSolution Activity and Marginal Value for all the scenario tables (BUY, SELL, PROCLIM, and CAPS).
To get the values populated once you have configured and saved your set file:
1. Run as a standalone case the one you configured as Base Case for the scenario.
In the following ex... |
Problem Statement: How to interpret Quality Change By Occurance and Quality Change By Relative Change in the | Solution: Tracking
Solution
In theSolution Tracking, there are Quality Change By Occurance and Quality Change By Relative Change results included to track the quality data.
1.Quality Change By Occurance
Under Quality Change By Occurance, it lists the top 50 properties based on how many times the property value is ch... |
Problem Statement: Warning message | Solution: files with no/multipleSolution IDs selected. Only spreadsheet report is supported while trying to generate Case comparison
For example, here while generating a case comparison of cases 1and 2, the warning message appears.
Solution
The reason for this warning message is that the cases were not run at the same ... |
Problem Statement: Most of the refiners that are processing both low sulphur and high sulphur crudes and producing fuel oil or any other product which is blended from straight run streams or where straight run streams properties are critical for product meeting specifications tend to split their crude units into logica... | Solution: easier.
When comparing planned and actual refinery yields refiners who process different types of crude may notice that their actual ratio of 1% vs 3% sulphur fuel oil may be different than planned.
This is due to the fact that crude and vacuum residue are present in the heel of the tank and in pipes whic... |
Problem Statement: What does uncrunching matrix in the execution log mean? | Solution: This message is simply an indication that the optimizer is returning to the original matrix after using the presolved matrix. It is normal to see this when the Presolve function is active. There is no problem and no action is required.
Keywords: uncrunching matrix
References: None |
Problem Statement: What is the difference between T.Gases and T.Units while using them to define units for gases? | Solution: There are the following things to take note of while using T.gases and T.units
1. User can only use one of the T.gases or T.units for a particular product
2. For T.gases, the conversion factor used is taken from the General Settings tab in the model tree. By default it converts from BBLS (Volume) ... |
Problem Statement: During a PIMS run, there is warning message 'Specification Blend Component Quality Data Missing'. Should I do something about it? | Solution: Warning message W086, 'SPECIFICATION BLEND COMPONENT QUALITY DATA MISSING', means that you have a specification on a finished product, but one or more of the blend components does not have that property assigned.
For example, let us assume that finished product C is made up of two blend components A and B. Pr... |
Problem Statement: When running in DR, to improve convergence in a model, you may try changing PGUESS, inverting PDIST, using MINOBJ, etc.
What are the equivalent options, settings and tips to improve the convergence and stability of a model using XNLP? | Solution: Here is a list of options and settings to try to improve the OBJFN and the stability of theSolution using XNLP.
1. Global Optimization | MultiStart
Use the Global Optimization MultiStart option under Model Settings | XNLP | Global Optimization.
This option will force test theSolution by starting the run fro... |
Problem Statement: What is the purpose of column VOL in T. BUY in weight based model and column “WGT” in a volume based model? | Solution: In T.BUY for a weight based model
For a weight based model, if you want to specify the purchase on volume basis, you can do so by giving a non-blank entry under the column VOL.
An entry “1” under the column VOL indicates that even though this is a weight based model, the purchase is on volume basis (volum... |
Problem Statement: What does the ‘Load Previous Case Basis’ option do in Aspen PIMS DR? | Solution: The ‘Load Previous Case Basis’ option can be found on the execution window as shown below:
This option initializes the basis for the subsequent case to be solved by starting from theSolution basis file of the previously solved case. It also initializes the flow basis in addition to the properties.
So, for... |
Problem Statement: Help file for T.DEMALLOC states:
Enter a five to eight character tag. The first three characters identify the material to be sold into a specific market, or the characters (…) that signify that the information provided in this row applies to all materials being sold in the specified market. The fourt... | Solution: “The optional fifth through eighth characters are plant identifiers” statement means that user can specify up to 4 plants that can satisfy the demand for each product into each market. For example:
UPRBACD would specify UPR to Market B from Plants A, C and D:
* TABLE
DEMALLOC
Table of Contents
*
... |
Problem Statement: I have a submodel which can operate in 2 modes, based on the feed quality. For example, if paraffin content of feed, PAR is less than 80%, it operates in mode 1. Else, operate in mode 2. How do I model this kind of situation? | Solution: You can use table SXXX (submodel) and table PROCLIM to model this kind of situation. For example, you have a submodel name SDHT, feed material is DS1. It operates in mode 2 when feed quality PAR (in this case paraffin content) is greater than 80%, it operates at mode 1 when PAR is less than 80%. I will create... |
Problem Statement: How to interpret the base-delta submodel structure | Solution: Base delta submodel is used for the scenario that the submodel feed quality will affect the yields. In the following example, the N+2A quality of the feed stream will affect the yields of H2L, LPG and R95.
The delta vectors in the base delta submodel represens the slopes of the each change (∆yield / ∆feed qua... |
Problem Statement: What is the best way to shut off/disconnect VPOOL for just certain cases within T Case? | Solution: The best way to disable vpool for a particular case would be to disable the column activity of the Virtual Pool in the T.SVPL, by fixing its min and max limits at zero in T.Bounds.
For example, if there is a virtual pool L+A consisting of ALK and LCN,
then in table CASE:
CASE 5
TABLE
BOUNDS
TEXT
... |
Problem Statement: When I right click on the Assays branch of my model and select Manage Assay Data, I get the following error message:
Duplicate coefficient in table <directory>\filename.xls[sheetname] for row *IFVTXXX column CRD
where XXX is the crude cut tag and CRD is the crude tag.
However, the only duplicates I... | Solution: Aspen Assay Manager will read commented out rows of the type *IFVT (also *IIVT, *FVT, and *IVT), along with the specified whole crude comment rows, such as *SULCRD.
Therefore, either delete the duplicate rows or, if you need them for calculations, change their names, so that there are no duplicates between co... |
Problem Statement: How can I blend two crudes to generate a new crude in Assay Manager | Solution: Blended crudes are a combination of two or more existing crudes and will be treated as a single feed. PIMS Assay Management can calculate the assay properties for the blended crude using the data of the component crudes.
Steps to blend crudes in Assay Manager:
1. Select Assays Summary on the navigation pan... |
Problem Statement: How can I report streams with no activities? | Solution: The purchases, sales and transfers with zero activities are reported unless the ZEROPS setting is selected.Â
Uncheck this option to report all the flows with zero activities in the fullSolution report.
Keywords: ZEROPS
Reporting settings
References: None |
Problem Statement: In different versions of PIMS, I see that the value for PrDBVersion in the ouput database (Results.mdb) has not changed (V7.3.1). What does it mean? | Solution: The value of V7.3.1 is currently hard-coded and does not get regularly updated. Nevertheless the database schema may have changed between versions.
Keywords: PrDBVersion, Results.mdb
References: None |
Problem Statement: How do I identify matrix rows with potential scaling problems? | Solution: It is important to avoid scaling issues in matrix rows because these can cause convergence problems. In general we recommend that the range of values for coefficients in a matrix row does not exceed 1e+7. For example, avoid a matrix row where one coefficient is 100,000 and another coefficient in the same ... |
Problem Statement: Can we use a finished product as a component to other blend? Although in general as a best practice, AspenTech does not recommend using a finished blend as a component for another blend, it is possible to do so. | Solution: Yes. A finished product can be used as a component to other blend. Consider this Example:
Product PRE and Product FIN are the blends defined. The user needs to use the Product PRE as a component in Product FIN. This can be implemented as follows:
1. Both PRE and FIN must be specification blends.
2. ... |
Problem Statement: When Excel Automation is running slowly, it will cause the “server busy” message, which could be caused by the Excel Add-ins. When the add-ins like PI-Datalink cannot be eliminated due to the business purposes, registry settings could be changed to reduce or resolve the problems. Note that these ste... | Solution: The following registry changes that may prevent the problems caused by Excel Add-Ins. Before making any registry changes you should consider if a backup of the registry should be made.
1) Click Start, click Run, type regedit, and then click OK.
2) Expand the following registry subkey: ... |
Problem Statement: Attached is a simple LP model that has multiple layers of cascaded pools and the source pool goes to more than one destinations, in this example, source pool ABD goes to destination pool ABE & ABF. Note that this LP model is not a representation of refinery or petrochemical PIMS model, this model is ... | Solution: The actual error distribution coefficient is 0.0000025, but it is reported as 0.001 in !PDIST.xls because a default value of 0.001 is defined in DSMALL under Model Settings | General | Tolerance, this DSMALL defines the minimum allowable value in the PDIST table.
Keywords: DSMALL
PDIST
Error Distribution Coef... |
Problem Statement: This | Solution: describes the functions of Aspen Process Industry Modeling System (PIMS) and how it is used.Solution
PIMS is an economic planning tool used to model industry processes, mainly refinery process. It is used to generate operating production plan for either a single plant or multiple plants; for a single period o... |
Problem Statement: What is the difference between the V8.0 and V8.2 installation of Aspen PIMS Platinum? | Solution: Platinum solo will be installed with PIMS installation. In V8.2, there is no short cut icon from 'All Programs | AspenTech | Planning 8.2'. This also means you can not run Platinum outside PIMS for client installation anymore.
In V8.0 version, the Platinum has its own icon from start menu. You can also run ... |
Problem Statement: Ranging Analysis is one of the features in the Aspen PIMS Advanced Optimization package (PIMS-AO). It is a tool to analyze the minimum and maximum range for feeds/products/capacities at or near optimal | Solution: .
The first step is to establish a base. Once we have the optimalSolution for this base case, we set the allowable percent giveaway in the objective function. During the Ranging Analysis, PIMS will minimize the lower bound for each selected variable and maximize the upper bound for each selected variable whil... |
Problem Statement: Aspen issues PIMS product major release, such as v7.1, v7.2, v7.3, v7.3.1, v7.3.2, v8.0, and v8.1. However within each major release, we may issue some patches with certain fixes. How does a user check which patch or which build they currently have installed or in use? | Solution: Open PIMS, from menu HELP | About Aspen PIMS. Next to the major release on the right, there is a series number which is the product patch/build number. In the screen below it is 18.60.6.
Keywords: patch
build
version
check
number
References: None |
Problem Statement: How do I resolve Getting | Solution: error message?Solution
Please follow below steps:
· Perform model clean up once
· Archive the model and unarchive in to a different folder and try to execute
· Delete PMLOG11.MDB file and run again
If the aboveSolutions are not helpful:
· Disable Antivirus software and ru... |
Problem Statement: What is the cause for the error `System Transactions Diagnostic Trace? threw an exception? | Solution: While trying to open PIMS the above error pos up preventing the application to open, this problem can be resolved by opening PIMS as an administrator
Keywords: System transaction error
System transactions
Diagnostic trace
References: None |
Problem Statement: How to formulate the LP (Linear Programming) model for a periodic problem? | Solution: In refinery industry, planning for several time periods may be required to meet the demands and increase the profits. In PIMS, we can use P-PIMS (Periodic PIMS) to set up multiple period model, which is based on linear programming system. To better explain the equations and relationship in P-PIMS LP system, a... |
Problem Statement: In which report can I find the matrix size of an Aspen PIMS DR model? | Solution: You may refer to the ExecutionLog.lst “Problem Size Characteristic� section to find out the matrix size.
          Â
Rows = number of rows/constraints in the matrix
Structural Columns = number of variables in the matrix
Integer variables and Special Ordered Sets are for MIP related variables
RH... |
Problem Statement: How do I turn off the Multi-Start graph when running multi-start on several cases at one time? | Solution: In Aspen PIMS V8.2, the Multi-start graph can be turned off if desired. To do this go to Model Settings | on-linear Model (XNLP) | Global Optimization. When Perform Global Optimization is checked and Multi-Start is selected, you can click on the Multi-Start... button and this opens the MultiStartOptionsForm s... |
Problem Statement: What factors can contribute to model convergence problems? | Solution: Factors that can contribute to model non-convergence include:
1. ATOL and RTOL too tight.
By default, ATOL (Absolute Tolerance) and RTOL (Relative Tolerance) are 0.001 in the model setting. But in some models, this tolerance can be too tight for some recursed properties to converge. We can change the ATOL a... |
Problem Statement: When a client machine try to run PIMS, it fails to access the license server. However the other machines can. What can be the cause? | Solution: In order for the Aspen application run on the client machine, the client machine has to be correctly configured so it is able to check out a license from the license server. This is implemented through the SLM tools.
The SLM tools are installed in sub-folders under C:\Program Files\ or C:\Program File (x86) f... |
Problem Statement: I am running a model highly influenced by crude slate. We are a small refinery only processing 2 cargoes of crude per month and the envisaged crude changes the stability of our model from one case to another. We have discovered that this is mostly due to the PGUESS being too far away from the expecte... | Solution: The obviousSolution here would be to switch to defining the opening inventories quality in PINV. If that is not a viable option one alternative would be to use the 999 PGUESS entry for the streams defined in assays table and to couple this with a CRDDISTL update which can be then done via table CASE.
The 99... |
Problem Statement: What does the invalid data in Excel during table loading error mean? | Solution: When PIMS-AO (XLP) reads the tables when you open a model, you may see the new message:
“There was invalid data in Excel during table loading. These cell entries will be ignored if you execute the model.”
This is not an error in terms of solving the model. It appears whenever there is data in an Excel spreads... |
Problem Statement: When importing an smc file into Aspen Petroleum Scheduler (APS), would -999 placeholders that derived their values from PCALC/PCALCB or BLNPROP tables have these calculations and values automatically brought over from Aspen PIMS? | Solution: It is not designed to import the fixed properties and PCALC factors with SMC files to APS.
The fixed properties or PCALC'ed properties from PIMS imported with SMC files can be used to resolve the -999's in the SMC submodel matrix because those values are input values. The fixed properties and PCALC factors in... |
Problem Statement: In the Scenario Evaluation Tool, for Override, Selection, and Parametric scenarios I see there are two columns: Activity and MarginalValue. What are these for and how do I get them populated? | Solution: These columns show the base caseSolution Activity and Marginal Value for all the scenario tables (BUY, SELL, PROCLIM, and CAPS).
To get the values populated once you have configured and saved your set file:
1. Run as a standalone case the one you configured as Base Case for the scenario.
In the following ex... |
Problem Statement: How to interpret Quality Change By Occurance and Quality Change By Relative Change in the | Solution: Tracking
Solution
In theSolution Tracking, there are Quality Change By Occurance and Quality Change By Relative Change results included to track the quality data.
1.Quality Change By Occurance
Under Quality Change By Occurance, it lists the top 50 properties based on how many times the property value is ch... |
Problem Statement: Warning message | Solution: files with no/multipleSolution IDs selected. Only spreadsheet report is supported while trying to generate Case comparison
For example, here while generating a case comparison of cases 1and 2, the warning message appears.
Solution
The reason for this warning message is that the cases were not run at the same ... |
Problem Statement: Most of the refiners that are processing both low sulphur and high sulphur crudes and producing fuel oil or any other product which is blended from straight run streams or where straight run streams properties are critical for product meeting specifications tend to split their crude units into logica... | Solution: easier.
When comparing planned and actual refinery yields refiners who process different types of crude may notice that their actual ratio of 1% vs 3% sulphur fuel oil may be different than planned.
This is due to the fact that crude and vacuum residue are present in the heel of the tank and in pipes whic... |
Problem Statement: What does uncrunching matrix in the execution log mean? | Solution: This message is simply an indication that the optimizer is returning to the original matrix after using the presolved matrix. It is normal to see this when the Presolve function is active. There is no problem and no action is required.
Keywords: uncrunching matrix
References: None |
Problem Statement: What is the difference between T.Gases and T.Units while using them to define units for gases? | Solution: There are the following things to take note of while using T.gases and T.units
1. User can only use one of the T.gases or T.units for a particular product
2. For T.gases, the conversion factor used is taken from the General Settings tab in the model tree. By default it converts from BBLS (Volume) ... |
Problem Statement: One important step in the transition between Distributive Recursion (DR) and XNLP is the comparison of results between the two methods.
As you have to run the model twice, changing the XNLP setting in between, the best way to do this analysis is with a Case Comparison report.
From Aspen PIMS version ... | Solution: To be able to run a Case Comparison between two cases, one with DR, the other with XNLP follow this procedure.
1. Change the Output Database Maintenance selection to Keep Existing or Only Unique Cases as shown below, so that different cases from different runs are stored in the database.
2. Create two dum... |
Problem Statement: What does the server busy message mean when running Excel Automation and how do I resolve it? | Solution: The server busy message is displayed when Excel Automation is running slowly. This could be due to Add-ins, formula errors, access issues, etc. Some tips for speeding up Excel Automation include:
? Minimize Excel add-ins
Minimize Conditional formatting in the Aspen PIMS input tables
Minimize macros ... |
Problem Statement: My model generates the error message during data validation:
*** Error. Is Both an Input and Output Tag in Correlation EPA.
It is not indicating what tag is duplicated, so how do I troubleshoot this? | Solution: This can happen if you have used an * to tell PIMS to ignore some of the input/output variable rows in Table ABML. For example, if you don't intend to use some of the input or output variables for a particular correlation, you may enter an * as seen in the left figure below. This can also happen if some of ... |
Problem Statement: How does Aspen PIMS generate a matrix for entries under IPRICE and ICOST. | Solution: IPRICE and ICOST are used in Aspen PIMS as the infeasibility breakers in the model. For example, in Table BUY in the Volume Sample model, IPRICE for crude BAC is $89/BBL, which means BAC can be sold at $89/BBL while it is bought at $90/BBL. The purpose is to eliminate the model infeasibilities although penalt... |
Problem Statement: Why ar excel outputs not generated if I choose output spreadsheet extension as .xlsx? | Solution: There is an EXCEL issue related to Office 2010 and probably 2007 as well. The problem is that Microsoft has configured EXCEL 2010 such that files saved in some older versions of EXCEL will be blocked from being opened or saved. If opened, they will be opened in protected view.
An example for this scenario wo... |
Problem Statement: How can I change a recursive quality to a fixed quality via table CASE? | Solution: You can use the keyword EMPTY in the CASE table to eliminate structure that exists in the base model tables. We will use the recursion structure below to demonstrate. This represents an excerpt of the base model table for SXYZ.
TABLE
SXYZ
TEXT
XXX
YYY
ZZZ
RBALZZZ
-1
-1
1
RSPGZZZ
-999
-999
999
... |
Problem Statement: Are there any conversion issues while trying to send data from a weight based PIMS model to a volume based APS model? | Solution: If you are seeing and comparing volumes, PIMS weight data have to be converted. It is better to do it in PIMS; create duplicate tags on the weight basis and send those to APS. If densities of the streams do not vary very much it is recommended to use constant conversion factors.Â
Keywords: PIMS APS Integratio... |
Problem Statement: Table BLNCAP allows the user to impose a capacity limit to each blender volumetric throughput for each set of blenders. It also allows the user to impose a component pumping limit to the blenders. In this | Solution: , we will demonstrate how it works.
Solution
We are using volume sample model as example here. We will demonstrate how PIMS works based on the specifications from the Table BLNCAP.
Let's assume we have 2 blenders. Blender 1 is defined as GB1 in PIMS. The maximum capacity is 100 for gasoline LRG, UPR and URG. ... |
Problem Statement: While working with PIMS-AO, sometimes the Internal Tables disappear from the model tree | Solution: If I close the table grid after running the model and then select “Restore Table Grid” the internal tables are still present and are again displayed.
Note that if “Reload Table Grid” is selected, PIMS will reload the model data from scratch, so the internal tables are gone. You cannot see them unless you ... |
Problem Statement: What is the matrix structure for process limits? | Solution: To add the process limits in the PIMS model, users need to set up the ZLIMXXX or ZquaXXX rows in the submodel and enter MIN/MAX limits in Table PROCLIM. In the matrix, The example below demonstrates this structure for ZSULCFP to control the sulfur content of the cat feed pool (CFP).
The abov... |
Problem Statement: If you are using BLNMIP (multiple integer tables for blending) you will most likely be familiar with the fact that there exists a possibility to limit the number of components that are entering a blend. Usually this is done since in-line blending equipment has a limited number of ports through which ... | Solution: TheSolution presented here is based on the SCFP submodel pool consisting of 6 components which can be found in the Volume Sample model present within the AspenTech folder of Public Documents on every computer with installed Aspen PIMS. This pool has 6 potential streams as components and theSolution of the bas... |
Problem Statement: How does Aspen PIMS Advanced Optimization using XLP initialize the first optimization? | Solution: In Aspen PIMS, the initialization process for XLP is related with the default initial setting, the values from Table PGUESS and the inputSolution file. PIMS will follow the follow 3 steps to initialize the optimization:
1. PIMS sets all values to the default initial settings, which will mostly affect non-... |
Problem Statement: What is the purpose of the Nqqqxxx and the Xqqqxxx In T. Sxxx? | Solution: An example would be if there was something like an additive that the user needs to insert into the spec row. Note that is needs to be a normal blend that is setup in Tables BLENDS, BLNMIX, BLNSPEC. This would only be necessary if the PIMS additive method (Table ADDITIVE) could not be used because the respon... |
Problem Statement: What does Primal Simplex method in the execution log of PIMS-DR means? | Solution: Primal Simplex is an algorithm to solve LP problems, it is one of the common methods to solve Linear Programming problems. Details on this algorithm can be referred texts such as: Advances in Linear and Integer Programming. Oxford Science, 1996, J. E. Beasley.
PIMS refinery LP are large scale (4000-75000 var... |
Problem Statement: When I run attached Gulf Coast sample model in PIMS, I found the messages below in the iteration log:
DISTRIBUTION MN1 TO NHT VALUE 1.13 EXCEEDS 1.00
DISTRIBUTION MN1 TO NHF VALUE 1.13 EXCEEDS 1.00
Why is the error distribution of MN1 to NNT and NHF exceeding 1 and how to resolve this? | Solution: MN1 is a deferred cut split from whole naphtha WN1 in submodel SNSP and fed into Naphtha Hydrotreater SNHT. When refering to matrix analyzer, we found a difference in the activity of SCD1MN1 (pool collector column for recursing quality of MN1 = 5089.93 bbl) vs. SNHTMN1 (amount of MN1 fed to SNHT = 5767.24 bbl... |
Problem Statement: From the Aspen PIMS menu, select Model | Open, select any model which has not yet been converted to V8.2. Choose Archive in the next screen, and Aspen PIMS may pop up the window below. The model is not opened. What does this mean?
Unable to find table in model: Volume Sample. This error usually occ... | Solution: When a table is suppressed on the Aspen PIMS model tree, PIMS is not going to use that file when generating the matrix. However, when PIMS archives the model before conversion to v8.2, PIMS requires that all the tables attached to the model tree exist - including the suppressed ones. So the message will appea... |
Problem Statement: How to use T.Case in 3rd normal format | Solution: An alternate format of table CASE is fully supported. That form is known as 3rd-normal. In that format, the column name(s) in the table are constant and the rows contain the data for each entry to be revised.
An example of this format is shown below:
Predefined Columns:
· CASE
· TITLE
· ... |
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