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©1998 AspenTech. All rights reserved.®

Septiembre 12, 2001 Introduction to Aspen PlusSeptiembre 12, 2001 Slide 1 Introduction to Aspen Plus

Aspen Technology, Inc.

Based on Aspen Plus® 10.1

December 1999

©1998 AspenTech. All rights reserved.

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Introduction toAspen Plus®



Contact Information

• Phone: 888-996-7001 or 617-949-1021

• Email: [email protected]

• Internet: http://www.aspentech.com

Technical Support Hotline

Training (Contact: Pat Sylvia)

Customized Support Services(Contact: Andrea Orchanian)



Course Agenda - Day 1

1. Introduction - General Simulation Concepts

2. The User Interface - Graphical Flowsheet Definition

3. Basic Input - Getting Around the Graphical UserInterface

4. Unit Operation Models - Overview of Available UnitOperations

5. RadFrac - Multistage Separation Model

6. Reactor Models - Overview of Available Reactor Types

7. Cyclohexane Production Workshop



Course Agenda - Day 2

8. Physical Properties - Overview of ThermodynamicModels, Basic Property Analysis and Reporting

9. Accessing Variables - Making References to FlowsheetVariables

10. Sensitivity Analysis - Studying Relationships BetweenProcess Variables

11. Design Specifications - Meeting Process Objectives

12. Fortran Blocks - Use of In-Line Fortran

13. Windows Interoperability - Transferring Data to and fromOther Windows Programs



Course Agenda - Day 314. Heat Exchangers - Heaters and Heat Exchangers

15. Pressure Changers - Pumps, Compressors, Pipes andValves

16. Flowsheet Convergence - Convergence Blocks, TearStreams and Flowsheet Sequences

17. Full-Scale Plant Modeling Workshop - Simulate aMethanol Plant



Additional Topics18. Maintaining Aspen Plus Simulations - Managing Aspen

Plus Files for Storage and Retrieval

19. Customizing the Look of Your Flowsheet - CreatingProcess Flow Diagrams

20. Estimation of Physical Properties - Overview ofProperty Estimation

21. Electrolytes - Introduction to the Use of Electrolytes

22. Solids Handling - Overview of the Solids Capabilities

23. Optimization - Optimizing a Flowsheet



Additional Topics (Continued)

24. RadFrac Convergence - Techniques for ConvergingDifficult Columns

25. VCM Workshop

26. ActiveX Automation



AppendicesA. Enthalpy Reference and Heat of Reaction

B. Workshop Instructions

C. Workshop Results

D. Final Workshop Hints

9Introduction to Aspen Plus

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Introduction

Objective:

Introduce general flowsheet simulation concepts andAspen Plus features



Introduction

• What is flowsheet simulation?

ðUse of a computer program to quantitatively model thecharacteristic equations of a chemical process

• Uses underlying physical relationships Mass and energy balance Equilibrium relationships Rate correlations (reaction and mass/heat transfer)

• Predicts Stream flowrates, compositions, and properties Operating conditions Equipment sizes



Advantages of Simulation• Reduces plant design time

Allows designer to quickly test various plantconfigurations

• Helps improve current process Answers “what if” questions Determines optimal process conditions within given

constraints Assists in locating the constraining parts of a process

(debottlenecking)



General Simulation ProblemWhat is the composition of stream PRODUCT?

• To solve this problem, we need: Material balances Energy balances

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUT SEP

PRODUCT



Approaches to Flowsheet Simulation• Sequential Modular

Aspen Plus is a sequential modular simulationprogram.

Each unit operation block is solved in a certainsequence.

• Equation Oriented Aspen Custom Modeler (formerly SPEEDUP) is an

equation oriented simulation program. All equations are solved simultaneously.

• Combination Aspen Dynamics (formerly DynaPLUS) uses the

Aspen Plus sequential modular approach to initializethe steady state simulation and the Aspen CustomModeler (formerly SPEEDUP) equation orientedapproach to solve the dynamic simulation.



Good Flowsheeting Practice• Build large flowsheets a few blocks at a time.

This facilitates troubleshooting if errors occur.

• Ensure flowsheet inputs are reasonable.

• Check that results are consistent and realistic.



Important Features of Aspen Plus• Rigorous Electrolyte Simulation

• Solids Handling

• Petroleum Handling

• Data Regression

• Data Fit

• Optimization

• User Routines


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The User Interface

Objective:

Become comfortable and familiar with the Aspen Plusgraphical user interface

Aspen Plus References:• User Guide, Chapter 1, The User Interface• User Guide, Chapter 2, Creating a Simulation Model• User Guide, Chapter 4, Defining the Flowsheet



The User Interface

Reference: Aspen Plus User Guide, Chapter 1, The User Interface

Run ID

Tool Bar

Title Bar

Menu Bar

Select Modebutton Model

Library

Model MenuTabs Process

FlowsheetWindow

Next Button

Status Area



Cumene Flowsheet Definition

RStoicModel

HeaterModel

Flash2Model

Filename: CUMENE.BKP

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUT SEP

PRODUCT



Using the Mouse• Left button click - Select object/field

• Right button click - Bring up menu for selected object/field, or inlet/outlet

• Double left click - Open Data Browser objectsheet

Reference: Aspen Plus User Guide, Chapter 1, The User Interface



Graphic Flowsheet OperationsTo place a block on the flowsheet:

1. Click on a model category tab in the Model Library.

2. Select a unit operation model. Click the drop-down arrowto select an icon for the model.

3. Click on the model and then click on the flowsheet toplace the block. You can also click on the model iconand drag it onto the flowsheet.

4. Click the right mouse button to stop placing blocks.



Graphic Flowsheet Operations (Continued)

• To place a stream on the flowsheet:1. Click on the STREAMS icon in the Model Library.2. If you want to select a different stream type (Material,

Heat or Work), click the down arrow next to the icon andchoose a different type.

3. Click a highlighted port to make the connection.4. Repeat step 3 to connect the other end of the stream.5. To place one end of the stream as either a process

flowsheet feed or product, click a blank part of theProcess Flowsheet window.

6. Click the right mouse button to stop creating streams.



Graphic Flowsheet Operations (Continued)

• To display an Input form for a Block or a Stream in the DataBrowser:1. Double click the left mouse button on the object of

interest.

• To Rename, Delete, Change the icon, provide input or viewresults for a block or stream:1. Select object (Block or Stream) by clicking on it with the

left mouse button.2. Click the right mouse button while the pointer is over the

selected object icon to bring up the menu for that object.3. Choose appropriate menu item.

Reference: Aspen Plus User Guide, Chapter 4, Defining the Flowsheet



Automatic Naming of Streams and Blocks

• Stream and block names can be automaticallyassigned by Aspen Plus or entered by the user whenthe object is created.

• Stream and block names can be displayed or hidden.

• To modify the naming options: Select Options from the Tools menu. Click the Flowsheet tab. Check or uncheck the naming options desired.



Benzene Flowsheet Definition WorkshopObjective: Create a graphical flowsheet

Start with the General with English Units Template. Choose the appropriate icons for the blocks. Rename the blocks and streams.

When finished, save in backupformat (Run-ID.BKP).filename: BENZENE.BKP

FL1

HeaterModel

Flash2

Model

Flash2

Model

COOL

FEED COOL

VAP1

LIQ1FL2

VAP2

LIQ2


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Basic Input

Objective:

Introduce the basic input required to run an Aspen Plussimulation

Aspen Plus References:• User Guide, Chapter 3, Using Aspen Plus Help• User Guide, Chapter 5, Global Information for Calculations• User Guide, Chapter 6, Specifying Components• User Guide, Chapter 7, Physical Property Methods• User Guide, Chapter 9, Specifying Streams• User Guide, Chapter 10, Unit Operation Models• User Guide, Chapter 11, Running Your Simulation



The User InterfaceMenus

Used to specify program options and commands

Toolbar Allows direct access to certain popular functions Can be moved Can be hidden or revealed using the Toolbars dialog

box from the View menu

Data Browser Can be moved, resized, minimized, maximized or

closed Used to navigate the folders, forms, and sheets



The User Interface (Continued)

Folders Refers to the root items in the Data Browser Contain forms

Forms Used to enter data and view results for the simulation Can be comprised of a number of sheets Are located in folders

Sheets Make up forms Are selected using tabs at the top of each sheet



The User Interface (Continued)

Object Manager Allows manipulation of discrete objects of information Can be created, edited, renamed, deleted, hidden, and

revealed

Next Button Checks if the current form is complete and skips to the

next form which requires input



The Data Browser

Menu tree

Previous sheet

Next sheet

Status area

Parent button Units

Go back Go forwardComments

Next

Description area

Status



Help

• Help Topics Contents - Used to browse through the

documentation. The User Guides and ReferenceManuals are all included in the help.• All of the information in the User Guides is found under

the “Using Aspen Plus” book. Index - Used to search for help on a topic using the

index entries Find - Used to search for a help on a topic that

includes any word or words

• “What’s This?” Help Select “What’s This?” from the Help menu and then

click on any area to get help for that item.



Functionality of Forms• When you select a field on a form (click left mouse button

in the field), the prompt area at the bottom of the windowgives you information about that field.

• Click the drop-down arrow in a field to bring up a list ofpossible input values for that field. Typing a letter will bring up the next selection on the

list that begins with that letter.

• The Tab key will take you to the next field on a form.



Basic Input

• The minimum required inputs (in addition to thegraphical flowsheet) to run a simulation are: Setup Components Properties Streams Blocks

• These inputs are all found in folders within the DataBrowser.

• These input folders can be located quickly using theData menu or the Data Browser buttons on the toolbar.



Status Indicators

Symbol StatusInput for the form is incomplete

Input for the form is complete

No input for the form has been entered. It is optional.

Results for the form exist.

Results for the form exist, but there were calculationerrors.

Results for the form exist, but there were calculationwarnings.

Results for the form exist, but input has changed sincethe results were generated.



Cumene Production Conditions

Q = 0 Btu/hrPdrop = 0 psi

C6H6 + C3H6 = C9H12Benzene Propylene Cumene (Isopropylbenzene)90% Conversion of Propylene

T = 130 FPdrop = 0.1 psi

P = 1 atmQ = 0 Btu/hr

Benzene: 40 lbmol/hrPropylene: 40 lbmol/hr

T = 220 FP = 36 psia

Use the RK-SOAVE Property Method

Filename: CUMENE.BKP

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUT SEP

PRODUCT



SetupMost of the commonly used Setup information is entered on

the Setup Specifications Global sheet:

• Flowsheet title to be used on reports

• Run type

• Input and output units

• Valid phases (e.g. vapor-liquid or vapor-liquid-liquid)

• Ambient pressure

Stream report options are located on the Setup ReportOptions Stream sheet.



Setup Specifications Form



Stream Report OptionsStream report options are located on the Setup Report

Options Stream sheet.



Setup Run TypesRun Type

Flowsheet Standard Aspen Plus flowsheet run including sensitivity studies and optimization.Flowsheet runs can contain property estimation, assay data analysis, and/or property analysiscalculations.

Assay DataAnalysis

A standalone Assay Data Analysis and pseudocomponent generation runUse Assay Data Analysis to analyze assay data when you do not want to perform a flowsheetsimulation in the same run.

DataRegression

A standalone Data Regression runUse Data Regression to fit physical property model parameters required by ASPEN PLUS tomeasured pure component, VLE, LLE, and other mixture data. Data Regression can containproperty estimation and property analysis calculations. ASPEN PLUS cannot perform dataregression in a Flowsheet run.

PROPERTIESPLUS

PROPERTIES PLUS setup runUse PROPERTIES PLUS to prepare a property package for use with Aspen Custom Modeler(formerly SPEEDUP) or Aspen Pinch (formerly ADVENT), with third-party commercialengineering programs, or with your company's in-house programs. You must be licensed to usePROPERTIES PLUS.

PropertyAnalysis

A standalone Property Analysis runUse Property Analysis to generate property tables, PT-envelopes, residue curve maps, and otherproperty reports when you do not want to perform a flowsheet simulation in the same run.Property Analysis can contain property estimation and assay data analysis calculations.

PropertyEstimation

Standalone Property Constant Estimation runUse Property Estimation to estimate property parameters when you do not want to perform aflowsheet simulation in the same run.



Setup Units• Units in Aspen Plus can be defined at 3 different levels:

1. Global Level (“Input Data” & “Output Results” fields onthe Setup Specifications Global sheet)

2. Object level (“Units” field in the top of any input formof an object such as a block or stream

3. Field Level

• Users can create their own units sets using the SetupUnits Sets Object Manager. Units can be copied from anexisting set and then modified.



Components• Use the Components Specifications form to specify all the

components required for the simulation.

• If available, physical property parameters for eachcomponent are retrieved from databanks.

• Pure component databanks contain parameters such asmolecular weight, critical properties, etc. The databanksearch order is specified on the Databanks sheet.

• The Find button can be used to search for components.

• The Electrolyte Wizard can be used to set up anelectrolyte simulation.



Components Specifications Form



Entering Components

• The Component ID is used to identify the component insimulation inputs and results.

• Each Component ID can be associated with a databankcomponent as either: Formula: Chemical formula of component (e.g., C6H6)

(Note that a suffix is added to formulas when there areisomers, e.g. C2H6O-2)

Component Name: Full name of component (e.g.,BENZENE)

• Databank components can be searched for using the Findbutton. Search using component name, formula, component

class, molecular weight, boiling point, or CAS number. All components containing specified items will be listed.



• Find performs an AND search when more than onecriterion is specified.

Find



Pure Component Databanks

Parameters missing from the first selected databank will be searched forin subsequent selected databanks.

Databank Contents Use

PURE10 Data from the Design Institute for PhysicalProperty Data (DIPPR) and AspenTech

Primary component databank inAspen Plus

AQUEOUS Pure component parameters for ionic andmolecular species in aqueous solution

Simulations containingelectrolytes

SOLIDS Pure component parameters for strongelectrolytes, salts, and other solids

Simulations containingelectrolytes and solids

INORGANIC Thermochemical properties for inorganiccomponents in vapor, liquid and solid states

Solids, electrolytes, andmetallurgy applications

PURE93 Data from the Design Institute for PhysicalProperty Data (DIPPR) and AspenTechdelivered with Aspen Plus 9.3

For upward compatibility

PURE856 Data from the Design Institute for PhysicalProperty Data (DIPPR) and AspenTechdelivered with Aspen Plus 8.5-6

For upward compatibility

ASPENPCD Databank delivered with Aspen Plus 8.5-6 For upward compatibility



Properties• Use the Properties Specifications form to specify the

physical property methods to be used in the simulation.

• Property methods are a collection of models and methodsused to describe pure component and mixture behavior.

• Choosing the right physical properties is critical forobtaining reliable simulation results.

• Selecting a Process Type will narrow the number ofmethods available.



Properties Specifications Form



Streams• Use Stream Input forms to specify the feed stream

conditions and composition.

• To specify stream conditions enter two of the following: Temperature Pressure Vapor Fraction

• To specify stream composition enter either: Total stream flow and component fractions Individual component flows

• Specifications for streams that are not feeds to theflowsheet are used as estimates.



Streams Input Form



Blocks

• Each Block Input or Block Setup form specifiesoperating conditions and equipment specifications forthe unit operation model.

• Some unit operation models require additionalspecification forms

• All unit operation models have optional informationforms (e.g. BlockOptions form).



Block Form



Starting the Run• Select Control Panel from the View menu or press the Next

button to be prompted. The simulation can be executed when all required forms

are complete. The Next button will take you to any incomplete forms.



Control Panel

The Control Panel consists of: A message window showing the progress of the

simulation by displaying the most recent messagesfrom the calculations

A status area showing the hierarchy and order ofsimulation blocks and convergence loops executed

A toolbar which you can use to control the simulation

Run Start or continue calculations

Step Step through the flowsheet oneblock at a time

Stop Pause simulation calculations

Reinitialize Purge simulation results

Results Check simulation results



Reviewing Results

• History file or Control Panel Messages Contains any generated errors or warnings Select History or Control Panel on the View menu to

display the History file or the Control Panel

• Stream Results Contains stream conditions and compositions

• For all streams (/Data/Results Summary/Streams)• For individual streams (bring up the stream folder in

the Data Browser and select the Results form)

• Block Results Contains calculated block operating conditions (bring

up the block folder in the Data Browser and selectthe Results form)



Benzene Flowsheet Conditions WorkshopObjective: Add the process and feed stream conditions to aflowsheet.

Starting with the flowsheet created in the Benzene FlowsheetDefinition Workshop (saved as BENZENE.BKP), add the processand feed stream conditions as shown on the next page.

Questions: 1. What is the heat duty of the block “COOL”? _________

2. What is the temperature in the second flash block “FL2”? _________

Note: Answers for all of the workshops are located in the veryback of the course notes in Appendix C.



Benzene Flowsheet Conditions Workshop

Feed

T = 1000 F

P = 550 psia

Hydrogen: 405 lbmol/hr

Methane: 95 lbmol/hr

Benzene: 95 lbmol/hr

Toluene: 5 lbmol/hr

T = 200 F

Pdrop = 0

T = 100 F

P = 500 psia

P = 1 atm

Q = 0

Use the PENG-ROB Property Method When finished, save asfilename: BENZENE.BKP

FL1COOL

FEED COOL

VAP1

LIQ1FL2

VAP2

LIQ2


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Unit Operation Models

Objective:

Review major types of unit operation models

Aspen Plus References:• User Guide, Chapter 10, Unit Operation Models• Unit Operation Models Reference Manual



Unit Operation Model Types• Mixers/Splitters• Separators• Heat Exchangers• Columns• Reactors• Pressure Changers• Manipulators• Solids• User Models

Reference: The use of specific models is best described by on-linehelp and the documentation.• Aspen Plus Unit Operation Models Reference Manual



Mixers/Splitters

Model Description Purpose Use

Mixer Stream mixer Combine multiplestreams into onestream

Mixing tees, stream mixingoperations, adding heatstreams, adding work streams

FSplit Stream splitter Split stream flows Stream splitters, bleed valves

SSplit Substream splitter Split substream flows Solid stream splitters, bleedvalves



Separators


Flash2 Two-outlet flash Determine thermaland phase conditions

Flashes, evaporators, knockoutdrums, single stage separators

Flash3 Three-outletflash

Determine thermaland phase conditions

Decanters, single stage separatorswith two liquid phases

Decanter Liquid-liquiddecanter

Determine thermaland phase conditions

Decanters, single stage separatorswith two liquid phases and no vaporphase

Sep Multi-outletcomponentseparator

Separate inlet streamcomponents into anynumber of outletstreams

Component separation operationssuch as distillation and absorption,when the details of the separation areunknown or unimportant

Sep2 Two-outletcomponentseparator

Separate inlet streamcomponents into twooutlet streams

Component separation operationssuch as distillation and absorption,when the details of the separation areunknown or unimportant



Heat ExchangersModel Description Purpose UseHeater Heater or cooler Determines thermal

and phase conditionsHeaters, coolers, valves. Pumps andcompressors when work-relatedresults are not needed.

HeatX Two-streamheat exchanger

Exchange heatbetween two streams

Two-stream heat exchangers. Ratingshell and tube heat exchangerswhen geometry is known.

MHeatX Multistreamheat exchanger

Exchange heatbetween any numberof streams

Multiple hot and cold stream heatexchangers. Two-stream heatexchangers. LNG exchangers.

Hetran* Interface toB-JAC Hetranprogram

Design and simulateshell and tube heatexchangers

Shell and tube heat exchangers witha wide variety of configurations.

Aerotran* Interface toB-JAC Aerotranprogram

Design and simulateair-cooled heatexchangers

Air-cooled heat exchangers with awide variety of configurations. Modeleconomizers and the convectionsection of fired heaters.

* Requires separate license



Columns - Shortcut

Model Description Purpose UseDSTWU Shortcut distillation

designDetermine minimum RR,minimum stages, and eitheractual RR or actual stagesby Winn-Underwood-Gilliland method.

Columns with one feed andtwo product streams

Distl Shortcut distillationrating

Determine separationbased on RR, stages, andD:F ratio using Edmistermethod.

Columns with one feed andtwo product streams

SCFrac Shortcut distillationfor petroleumfractionation

Determine productcomposition and flow,stages per section, dutyusing fractionation indices.

Complex columns, such ascrude units and vacuumtowers



Columns - RigorousModel Description Purpose UseRadFrac Rigorous

fractionationRigorous rating and design for singlecolumns

Distillation, absorbers, strippers,extractive and azeotropic distillation,reactive distillation

MultiFrac Rigorousfractionation forcomplex columns

Rigorous rating and design formultiple columns of any complexity

Heat integrated columns, air separators,absorber/stripper combinations, ethyleneprimary fractionator/quench towercombinations, petroleum refining

PetroFrac Petroleum refiningfractionation

Rigorous rating and design forpetroleum refining applications

Preflash tower, atmospheric crude unit,vacuum unit, catalytic cracker or cokerfractionator, vacuum lube fractionator,ethylene fractionator and quench towers

BatchFrac*+ Rigorous batchdistillation

Rigorous rating calculations forsingle batch columns

Ordinary azeotropic batch distillation, 3-phase, and reactive batch distillation

RateFrac* Rate-baseddistillation

Rigorous rating and design for singleand multiple columns. Based onnonequilibrium calculations

Distillation columns, absorbers, strippers,reactive systems, heat integrated units,petroleum applications

Extract Liquid-liquidextraction

Rigorous rating for liquid-liquidextraction columns

Liquid-liquid extraction

* Requires separate license+ Input language only in Version 10.0



Model Description Purpose UseRStoic Stoichiometric

reactorStoichiometric reactor withspecified reaction extent orconversion

Reactors where the kinetics are unknown orunimportant but stoichiometry and extent areknown

RYield Yield reactor Reactor with specified yield Reactors where the stoichiometry and kineticsare unknown or unimportant but yielddistribution is known

REquil Equilibrium reactor Chemical and phaseequilibrium bystoichiometric calculations

Single- and two-phase chemical equilibriumand simultaneous phase equilibrium

RGibbs Equilibrium reactor Chemical and phaseequilibrium by Gibbsenergy minimization

Chemical and/or simultaneous phase andchemical equilibrium. Includes solid phaseequilibrium.

RCSTR Continuous stirredtank reactor

Continuous stirred tankreactor

One, two, or three-phase stirred tank reactorswith kinetics reactions in the vapor or liquid

RPlug Plug flow reactor Plug flow reactor One, two, or three-phase plug flow reactors withkinetic reactions in any phase. Plug flowreactions with external coolant.

RBatch Batch reactor Batch or semi-batchreactor

Batch and semi-batch reactors where thereaction kinetics are known

Reactors



Pressure ChangersModel Description Purpose Use

Pump Pump orhydraulicturbine

Change stream pressure whenthe pressure, power requirementor performance curve is known

Pumps and hydraulic turbines

Compr Compressor orturbine

Change stream pressure whenthe pressure, power requirementor performance curve is known

Polytropic compressors, polytropicpositive displacementcompressors, isentropiccompressors, isentropic turbines.

MCompr Multi-stagecompressor orturbine

Change stream pressure acrossmultiple stages with intercoolers.Allows for liquid knockoutstreams from intercoolers

Multistage polytropic compressors,polytropic positive compressors,isentropic compressors, isentropicturbines.

Valve Control valve Determine pressure drop orvalve coefficient (CV)

Multi-phase, adiabatic flow in ball,globe and butterfly valves

Pipe Single-segmentpipe

Determine pressure drop andheat transfer in single-segmentpipe or annular space

Multi-phase, one dimensional,steady-state and fully developedpipeline flow with fittings

Pipeline Multi-segmentpipe

Determine pressure drop andheat transfer in multi-segmentpipe or annular space

Multi-phase, one dimensional,steady-state and fully developedpipeline flow



Manipulators


Mult Stream multiplier Multiply stream flows bya user supplied factor

Multiply streams for scale-up orscale-down

Dupl Streamduplicator

Copy a stream to anynumber of outlets

Duplicate streams to look atdifferent scenarios in the sameflowsheet

ClChng Stream classchanger

Change stream class Link sections or blocks that usedifferent stream classes



Solids

Model Description UsesCrystallizer Continuous Crystallizer Mixed suspension, mixed product removal (MSMPR)

crystallizeer used for the production of a single solid product

Crusher Crushers Gyratory/jaw crusher, cage mill breaker, and single ormultiple roll crushers

Screen Screens Solids-solids separation using screens

FabFl Fabric filters Gas-solids separation using fabric filters

Cyclone Cyclones Gas-solids separation using cyclones

VScrub Venturi scrubbers Gas-solids separation using venturi scrubbers

ESP Dry electrostatic precipitators Gas-solids separation using dry electrostatic precipitators

HyCyc Hydrocyclones Liquid-solids separation using hydrocyclones

CFuge Centrifuge filters Liquid-solids separation using centrifuge filters

Filter Rotary vacuum filters Liquid-solids separation using continuous rotary vacuumfilters

SWash Single-stage solids washer Single-stage solids washer

CCD Counter-current decanter Multistage washer or a counter-current decanter



User Models

• Proprietary models or 3-rd party software can beincluded in an Aspen Plus flowsheet using a User2 unitoperation block.

• Excel Workbooks or Fortran code can be used to definethe User2 unit operation model.

• User-defined names can be associated with variables.

• Variables can be dimensioned based on other inputspecifications (for example, number of components).

• Aspen Plus helper functions eliminate the need to knowthe internal data structure to retrieve variables.



Subflowsheets

• Existing simulations (*.bkp or *.apw files) can be usedas part of a new flowsheet

• Select “Subflowsheet” from the User Model tab of theModel Library to create a subflowsheet in the mainflowsheet.

• Inlet and outlet streams must have the same name inthe subflowsheet and in the main flowsheet.

• Components must be identical in all flowsheets.

• Each ID (block, stream, design-spec, etc.) must beunique.



Model Templating

• Custom model libraries containing categorized groupsof models can be displayed with the Aspen Plus ModelLibrary.

• Any Aspen Plus model on the flowsheet can be addedto the custom model library. Any data entered for theblock will be associated with that model.

• Custom icons to better represent the equipment can becreated for any model in a custom model library.



Model Templating (Continued)

1. Create a custom model library, by selecting New fromthe Library menu. Enter the name of the library and thelocation of the library file.

2. Edit the library by selecting the library name and Editfrom the Library menu.

3. Create categories by selecting New from the Categorymenu.

4. Add models to the library by selecting a block on theflowsheet, clicking the right mouse button, andselecting “Add to model library” from the list.

5. Select Save from the Library menu to save the library.


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RadFrac

Objective:

Discuss the minimum input required for the RadFracfractionation model, and the use of design specificationsand stage efficiencies

Aspen Plus References:• Unit Operation Models Reference Manual, Chapter 4, Columns



RadFrac: Rigorous Multistage Separation

• Vapor-Liquid or Vapor-Liquid-Liquid phase simulation of: Ordinary distillation Absorption, reboiled absorption Stripping, reboiled stripping Azeotropic distillation Reactive distillation

• Configuration options: Any number of feeds Any number of side draws Total liquid draw off and pumparounds Any number of heaters Any number of decanters



RadFrac Flowsheet Connectivity

Vapor Distillate

Top-Stage or 1 Condenser Heat Duty Heat (optional)

Liquid DistillateWater Distillate (optional)

Feeds

Reflux

Products (optional)Heat (optional)

Pumparound

DecantersHeat (optional)

ProductHeat (optional)

ReturnBoil-up

Bottom Stage or NstageReboiler Heat Duty Heat (optional)

Bottoms



• Specify: Number of stages Condenser and reboiler configuration Two column operating specifications Valid phases Convergence

RadFrac Setup Configuration Sheet



RadFrac Setup Streams Sheet

• Specify: Feed stage location Feed stream convention (see Help)

ABOVE-STAGE:Vapor from feed goes to stage above feed stageLiquid goes to feed stage

ON-STAGE:Vapor & Liquid from feed go to specified feed stage



Feed Convention

On-stage

n

Above-stage(default)

n-1

n

Vapor

Feed

n-1

Liquid

Feed



RadFrac Setup Pressure Sheet

• Specify one of: Column pressure profile Top/Bottom pressure Section pressure drop



Kettle Reboiler

T = 65 CP = 1 bar

Water: 100 kmol/hrMethanol: 100 kmol/hr

9 Stages

Reflux Ratio = 1Distillate to feed ratio = 0.5Column pressure = 1 barFeed stage = 6

RadFrac specifications

Filename: RAD-EX.BKP

Methanol-Water RadFrac Column

Use the NRTL-RK Property Method

COLUMNFEED

OVHD

BTMS

Total Condenser



RadFrac Options• To set up an absorber with no condenser or reboiler, set

condenser and reboiler to none on the RadFrac SetupConfiguration sheet.

• Either Vaporization or Murphree efficiencies on either astage or component basis can be specified on theRadFrac Efficiencies form.

• Tray and packed column design and rating is possible.

• A Second liquid phase may be modeled if the user selectsVapor-liquid-liquid as Valid phases.

• Reboiler and condenser heat curves can be generated.



Plot Wizard

• Use Plot Wizard (on the Plot menu) to quickly generateplots of results of a simulation. You can use Plot Wizardfor displaying results for the following operations: Physical property analysis Data regression analysis Profiles for all separation models RadFrac, MultiFrac,

PetroFrac and RateFrac

• Click the object of interest in the Data Browser togenerate plots for that particular object.

• The wizard guides you in the basic operations forgenerating a plot.

• Click on the Next button to continue. Click on theFinish button to generate a plot with default settings.



Plot Wizard Demonstration

• Use the plot wizard on the column to create a plot ofthe vapor phase compositions throughout the column.

Block COLUMN: Vapor Composition Profiles

Stage1 2 3 4 5 6 7 8 9

Y (

mol

e fr

ac)

0.25

0.5

0.75

1WATERMETHANOL



RadFrac DesignSpecs and Vary• Design specifications can be specified and executed

inside the RadFrac block using the DesignSpecs andVary forms.

• One or more RadFrac inputs can be manipulated toachieve specifications on one or more RadFracperformance parameters.

• The number of specs should, in general, be equal to thenumber of varies.

• The DesignSpecs and Varys in a RadFrac are solved in a“Middle loop.” If you get an error message saying that themiddle loop was not converged, check the DesignSpecsand Varys you have entered.



RadFrac Convergence ProblemsIf a RadFrac column fails to converge, doing one or more ofthe following could help:

1. Check that physical property issues (choice ofProperty Method, parameter availability, etc.) areproperly addressed.

2. Ensure that column operating conditions are feasible.

3. If the column err/tol is decreasing fairly consistently,increase the maximum iterations on the RadFracConvergence Basic sheet.



RadFrac Convergence Problems (Continued)

4. Provide temperature estimates for some stages inthe column using the RadFrac EstimatesTemperature sheet (useful for absorbers).

5. Provide composition estimates for some stages inthe column using the RadFrac Estimates LiquidComposition and Vapor Composition sheet (usefulfor highly non-ideal systems).

6. Experiment with different convergence methods onthe RadFrac Setup Configuration sheet.

>> When a column does not converge, it is usuallybeneficial to Reinitialize after making changes.



Filename: RADFRAC.BKP

RadFrac Workshop

Use the NRTL-RK Property Method

COLUMNFEED

DIST

BTMS

Feed:63.2 wt% Water 36.8 wt% MethanolTotal flow = 120,000 lb/hrPressure 18 psia Saturated liquid

Column specification: 38 trays (40 stages)Feed tray = 23 (stage 24)Total condenserTop stage pressure = 16.1 psiaPressure drop per stage = 0.1 psiDistillate flowrate = 1245 lbmol/hrMolar reflux ratio = 1.3

Part A:

• Perform a rating calculation of a Methanol tower using the followingdata:



RadFrac Workshop (Continued)

Part B:

• Set up design specifications within the column so the following twoobjectives are met:

99.95 wt% methanol in the distillate 99.90 wt% water in the bottoms

• To achieve these specifications, you can vary the distillate rate (800-1700 lbmol/hr) and the reflux ratio (0.8-2). Make sure streamcompositions are reported as mass fractions before running theproblem. Note the condenser and reboiler duties:

Condenser Duty :_________

Reboiler Duty :_________



RadFrac Workshop (Continued)

Part C:

• Perform the same design calculation after specifying a 65% Murphreeefficiency for each tray. Assume the condenser and reboiler havestage efficiencies of 90%.

• How do these efficiencies affect the condenser and reboiler duties ofthe column?

Part D:

• Perform a tray sizing calculation for the entire column, given thatBubble Cap trays are used.

(When finished, save as filename: RADFRAC.BKP)


Potential

Reach Your

True


Reactor Models

Objective:

Introduce the various classes of reactor modelsavailable, and examine in some detail at least onereactor from each class

Aspen Plus References:• Unit Operation Models Reference Manual, Chapter 5, Reactors



Reactor Overview

Reactors

Balance BasedRYieldRStoic

Equilibrium BasedREquilRGibbs

Kinetics BasedRCSTRRPlug

RBatch



Balanced Based Reactors• RYield

Requires a mass balance only, not an atom balance Is used to simulate reactors in which inlets to the

reactor are not completely known but outlets areknown (e.g. to simulate a furnace)

70 lb/hr H2O20 lb/hr CO260 lb/hr CO250 lb/hr tar600 lb/hr char

1000 lb/hr Coal

IN

OUT

RYield



Balanced Based Reactors (Continued)

• RStoic Requires both an atom and a mass balance Used in situations where both the equilibrium data and

the kinetics are either unknown or unimportant Can specify or calculate heat of reaction at a reference

temperature and pressure

2 CO + O2 --> 2 CO2C + O2 --> CO22 C + O2 --> 2 CO

C, O2

IN

OUT

RStoic

C, O2, CO, CO2



Equilibrium Based Reactors• GENERAL

Do not take reaction kinetics into account Solve similar problems, but problem specifications are

different Individual reactions can be at a restricted equilibrium

• REquil Computes combined chemical and phase equilibrium

by solving reaction equilibrium equations Cannot do a 3-phase flash Useful when there are many components, a few known

reactions, and when relatively few components takepart in the reactions



Equilibrium Based Reactors (Continued)

• RGibbs Unknown Reactions

This feature is quite useful when reactions occurringare not known or are high in number due to manycomponents participating in the reactions.

Gibbs Energy MinimizationA Gibbs free energy minimization is done to determinethe product composition at which the Gibbs freeenergy of the products is at a minimum.

Solid EquilibriumRGibbs is the only Aspen Plus block that will deal withsolid-liquid-gas phase equilibrium.



Kinetic Reactors• Kinetic reactors are RCSTR, RPlug and RBatch.

• Reaction kinetics are taken into account, and hence mustbe specified.

• Kinetics can be specified using one of the built-in models,or with a user subroutine. The current built-in models are Power Law Langmuir-Hinshelwood-Hougen-Watson (LHHW)

• A catalyst for a reaction can have a reaction coefficient ofzero.

• Reactions are specified using a Reaction ID.



Using a Reaction ID• Reaction IDs are setup as objects, separate from the

reactor, and then referenced within the reactor(s).

• A single Reaction ID can be referenced in any number ofkinetic reactors (RCSTR, RPlug and RBatch.)

• To set up a Reaction ID, go to the Reactions ReactionsObject Manager



Power-law Rate Expression

−−

−=

0

n

0

11Energy Activationexp Factor) lexponentiaPre(

TTRTT

k

rate k concentrationii

= ∏* [ ]exponent i

Example: 2 3 21

2A B C D

k

k+ →

← +

Forward reaction: (Assuming the reaction is 2nd order in A)coefficients: A: B: C: D:exponents: A: B: C: D:

-2 -3 1 2 2 0 0 0

Reverse reaction: (Assuming the reaction is 1st order in C and D)coefficients: C: D: A: B: exponents: C: D: A: B:

-1 -2 2 3 1 1 0 0



Heats of Reaction• Heats of reaction need not be provided for reactions.

• Heats of reaction are typically calculated as the differencebetween inlet and outlet enthalpies for the reactor (seeAppendix A).

• If you have a heat of reaction value that does not matchthe value calculated by Aspen Plus, you can adjust theheats of formation (DHFORM) of one or morecomponents to make the heats of reaction match.

• Heats of reaction can also be calculated or specified at areference temperature and pressure in an RStoic reactor.



Reactor WorkshopObjective: Compare the use of different reactor types tomodel one reaction.

Reactor Conditions:Temperature = 70 CPressure = 1 atm

Stoichiometry:Ethanol + Acetic Acid <--> Ethyl Acetate + Water

Kinetic Parameters:Forward Reaction: Pre-exp. Factor = 1.9 x 108,Act. Energy = 5.95 x 107 J/kmolReverse Reaction: Pre-exp. Factor = 5.0 x 107,Act. Energy = 5.95 x 107 J/kmol

Reactions are first order with respect to each of the reactants in the reaction (secondorder overall).

Reactions occur in the liquid phase.Composition basis is Molarity.

Hint: Check that each reactor is considering both Vapor and Liquid as Valid phases.



Reactor Workshop (Continued)

Temp = 70 CPres = 1 atm

Feed:

Water: 8.892 kmol/hrEthanol: 186.59 kmol/hrAcetic Acid: 192.6 kmol/hr

Length = 2 metersDiameter = 0.3 meters

Volume = 0.14 Cu. M.

70 % conversion of ethanol

When finished, save asfilename: REACTORS.BKP

Use the NRTL-RK property method

RSTOICF-STOIC

P-STOIC

RGIBBS

F-GIBBS P-GIBBS

RPLUGF-PLUG P-PLUG

DUPL

FEED

F-CSTR

RCSTR

P-CSTR


Potential

Reach Your

True


Cyclohexane Production Workshop



Cyclohexane Production WorkshopObjective: Create a flowsheet to model a cyclohexaneproduction process

Cyclohexane can be produced by the hydrogenation of benzene in thefollowing reaction:

C6H6 + 3 H2 = C6H12Benzene Hydrogen Cyclohexane

The benzene and hydrogen feeds are combined with recycle hydrogenand cyclohexane before entering a fixed bed catalytic reactor. Assumea benzene conversion of 99.8%.

The reactor effluent is cooled and the light gases separated from theproduct stream. Part of the light gas stream is fed back to the reactor asrecycle hydrogen.

The liquid product stream from the separator is fed to a distillationcolumn to further remove any dissolved light gases and to stabilize theend product. A portion of the cyclohexane product is recycled to thereactor to aid in temperature control.



Cyclohexane Production Workshop C6H6 + 3 H2 = C6H12Benzene Hydrogen Cyclohexane

Use the RK-SOAVE property method

When finished, save asfilename: CYCLOHEX.BKP

Bottoms rate = 99 kmol/hr

P = 25 barT = 50 C

Molefrac H2 = 0.975N2 = 0.005CH4 = 0.02

Total flow = 330 kmol/hr

T = 40 CP = 1 barBenzene flow = 100 kmol/hr

T = 150CP = 23 bar T = 200 C

Pdrop = 1 barBenzene conv =

0.998

T = 50 CPdrop = 0.5 bar

92% flow to stream H2RCY

30% flow to stream CHRCY

Specify cyclohexane molerecovery of 0.9999 by varyingBottoms rate from 97 to 101 kmol/hr

Theoretical Stages = 12Reflux ratio = 1.2

Partial Condenser with vapor distillate onlyColumn Pressure = 15 barFeed stage = 8

REACTFEED-MIXH2IN

BZIN

H2RCY

CHRCY

RXIN

RXOUT

HP-SEP

VAP

COLUMN

COLFD

LTENDS

PRODUCT

VFLOW

PURGE

LFLOW

LIQ


Potential

Reach Your

True


Physical Properties

Objectives:

Introduce the ideas of property methods and physicalproperty parametersIdentify issues involved in the choice of a property methodCover the use of Property Analysis for reporting physicalproperties

Aspen Plus References:• User Guide, Chapter 7, Physical Property Methods• User Guide, Chapter 8, Physical Property Parameters and Data• User Guide, Chapter 29, Analyzing Properties



Case Study - Acetone Recovery• Correct choice of physical property models and accurate

physical property parameters are essential for obtainingaccurate simulation results.

IdealApproach

Equation ofState Approach

Activity CoefficientModel Approach

Predicted number of stagesrequired

11 7 42

Approximate cost in dollars 520,000 390,000 880,000

FEED

OVHD

BTMS

COLUMN

5000 lbmol/hr10 mole % acetone90 mole % water

Specification: 99.5 mole % acetone recovery



How to Establish Physical Properties

Choose a Property Method

Check Parameters/ObtainAdditional Parameters

Confirm Results

Create the Flowsheet



Property Methods• A Property Method is a collection of models and methods

used to calculate physical properties.

• Property Methods containing commonly usedthermodynamic models are provided in Aspen Plus.

• Users can modify existing Property Methods or createnew ones.



Approaches to representing physical properties ofcomponents

Physical Property Models

Ideal Equation of State Activity Special(EOS) Coefficient ModelsModels Models

Physical Property Models

• Choice of model types depends on degree of non-idealbehavior and operating conditions.



Ideal vs. Non-Ideal Behavior• What do we mean by ideal behavior?

Ideal Gas law and Raoult’s law

• Which systems behave as ideal? Non-polar components of similar size and shape

• What controls degree of non-ideality? Molecular interactions

e.g. Polarity, size and shape of the molecules

• How can we study the degree of non-ideality of a system? Property plots (e.g. TXY & XY)

x

y

x

y

x

y



Comparison of EOS and Activity Models

EOS Models Activity Coefficient Models

Limited in ability to representnon-ideal liquids

Can represent highly non-ideal liquids

Fewer binary parametersrequired

Many binary parameters required

Parameters extrapolatereasonably with temperature

Binary parameters are highlytemperature dependent

Consistent in critical region Inconsistent in critical region



Common Property Methods• Equation of State Property Methods

PENG-ROB RK-SOAVE

• Activity Coefficient Property Methods NRTL UNIFAC UNIQUAC WILSON



Henry's Law• Henry's Law is only used with ideal and activity coefficient

models.

• It is used to determine the amount of a supercriticalcomponent or light gas in the liquid phase.

• Any supercritical components or light gases (CO2, N2,etc.) should be declared as Henry's components(Components Henry Comps Selection sheet).

• The Henry's components list ID should be entered onProperties Specifications Global sheet in the HenryComponents field.



Choosing a Property Method - ReviewDo you have anypolar componentsin your system?

Are the operating conditionsnear the critical region of themixture?

Do you have light gases orsupercritical componentsin your system?

Use activitycoefficient modelwith Henry’s Law

Use activitycoefficientmodel

Use EOS Model

N

N

NY

Y

Y

Reference: Aspen Plus UserGuide, Chapter 7, PhysicalProperty Methods, givessimilar, more detailedguidelines for choosing aProperty Method.



Choosing a Property Method - Example

Choose an appropriate Property Method for the followingsystems of components at ambient conditions.

System Model Type Property MethodPropane, Ethane, Butane EOS RK-SOAVE, PENG-ROB

Benzene, Water Activity Coefficient NRTL-RK, UNIQUAC

Acetone, Water Activity Coefficient NRTL-RK, WILSON

System Property Method

Ethanol, Water

Benzene, Toluene

Acetone, Water, Carbon Dioxide

Water, Cyclohexane

Ethane and Propanol






Confirm Results




Pure Component Parameters• Represent attributes of a single component

• Input in the Properties Parameters Pure Componentfolder.

• Stored in databanks such as PURE10, ASPENPCD,SOLIDS, etc. (The selected databanks are listed on theComponents Specifications Databanks sheet.)

• Parameters retrieved into the Graphical User Interface byselecting Retrieve Parameter Results from the tools menu.

• Examples Scalar: MW for molecular weight Temperature-Dependent: PLXANT for parameters in

the extended Antoine vapor pressure model



Binary Parameters• Used to describe interactions between two components

• Input in the Properties Parameters Binary Interactionfolder

• Stored in binary databanks such as VLE-IG, LLE-ASPEN

• Parameter values from the databanks can be viewed onthe input forms in the Graphical User Interface.

• Parameter forms that include data from the databanksmust be viewed before the flowsheet is complete.

• Examples Scalar: RKTKIJ for the Rackett model Temperature-Dependent: NRTL for parameters in the

NRTL model



Displaying Property Parameters

• Aspen Plus does not display all databank parameterson the parameter input forms.

• Select Retrieve Parameter Results from the Toolsmenu to retrieve all parameters for the components andproperty methods defined in the simulation.

• All results that are currently loaded will be lost. Theycan be regenerated by running the simulation again.

• The parameters are viewed on the PropertiesParameters Results forms.



Reporting Physical Property ParametersFollow this procedure to obtain a report file containingvalues of ALL pure component and binary parameters forALL components used in a simulation:

1. On the Setup Report Options Property sheet,select All physical property parameters used (in SIunits) or select Property parameters’ descriptions,equations, and sources of data.

2. After running the simulation, export a report (*.rep)file (Select Export from the File menu).

3. Edit the .rep file using any text editor. (From theGraphical User Interface, you can choose Reportfrom the View menu.) The parameters are listedunder the heading PARAMETER VALUES in thephysical properties section of the report file.



Parameter Reports

All physical propertyparameters used(in SI units)

Property parameters’descriptions, equations,and sources of data

Parameters are reported in SIunits, and the units of theparameters are not printed.

Parameters are reported inoutput-units, and the units of theparameters are printed.

Only Aspen Plus abbreviations forthe parameter names are printed.

Aspen Plus abbreviation alongwith a description is printed

Output is fairly compact. Output is quite long.

Equations for temperature-dependent parameters are listed.






Confirm Results




Property Analysis• Used to generate simple property diagrams to validate

physical property models and data

• Diagram Types: Pure component, e.g. Vapor pressure vs. temperature Binary, e.g. TXY, PXY Ternary residue maps

• Select Analysis from the Tools menu to start Analysis.

• Additional binary plots are available under the PlotWizard button on result form containing raw data.

• When using a binary analysis to check for liquid-liquidphase separation, remember to choose Vapor-Liquid-Liquid as Valid phases.

• Property analysis input and results can be saved as aform for later reference and use.



Property Analysis - Common PlotsIdeal XY Plot: XY Plot Showing Azeotrope:

XY Plot Showing 2 liquid phases:

y-x diagram for METHANOL / PROPANOL

LIQUID MOLEFRAC METHANOL0 0.2 0.4 0.6 0.8 1

0.

20

.4

0.

60

.8

1

VA

PO

R

MO

LE

FR

AC

M

ET

HA

NO

L

(PRES = 14.7 PSI)

y-x diagram for ETHANOL / TOLUENE

LIQUID MOLEFRAC ETHANOL0 0.2 0.4 0.6 0.8 1

0.

20

.4

0.

60

.8

1

VA

PO

R

MO

LE

FR

AC

E

TH

AN

OL

(PRES = 14.7 PSI)

y-x diagram for TOLUENE / WATER

LIQUID MOLEFRAC TOLUENE0 0.2 0.4 0.6 0.8 1

0.

20

.4

0.

60

.8

1

VA

PO

R

MO

LE

FR

AC

T

OL

UE

NE

(PRES = 14.7 PSI)



Additional Data from DETHERM

• DETHERM databank is maintained by DECHEMA.

• DETHERM contains the world’s most comprehensivesingle source of thermophysical properties. Phase equilibria data Azeotropic data Excess properties PVT data Caloric properties Transport properties Electrolyte data

• The interface can be launched from within Aspen Plus toaccess data via the Internet or CD-ROM.

• Users are charged for each set of data that is downloaded.• Data can be regressed using Aspen Plus Data Regression.



Interface to DETHERM Example

1. Enter your components on the Components Specifications Selection sheet.

2. Click on the DETHERM Interface button on the toolbar.

3. Click on the Search button in the DETHERM interface.

4. Select the data sets from the list of data.

5. Click on the Transfer button.

6. Enter your user ID information.

7. Receive the data into Aspen Plus. Scalar data is entered on Property Parameters forms. Temperature dependent and Binary data sets are

entered on the Properties Data forms.



Interface to the DETHERM Databank

• For more information The AspenTech partnership with DECHEMA Download and usage of DETHERM Internet Client How to sign up for an account

http://www.aspentech.com/partner/. (then click on DECHEMA)






Confirm Results




Establishing Physical Properties - Review1. Choose Property Method - Select a Property Method based on

Components present in simulation Operating conditions in simulation Available data or parameters for the components

2. Check Parameters - Determine parameters available in AspenPlus databanks

3. Obtain Additional Parameters (if necessary) - Parameters thatare needed can be obtained from Literature searches Regression of experimental data (Data Regression) Property Constant Estimation (Property Estimation)

4. Confirm Results - Verify choice of Property Method andphysical property data using Physical Property Analysis



Property Sets• A property set (Prop-Set) is a way of accessing a

collection, or set, of properties as an object with a user-given name. Only the name of the property set isreferenced when using the properties in an application.

• Use property sets to report thermodynamic, transport, andother property values.

• Current property set applications include: Design specifications, Fortran blocks, sensitivity Stream reports Physical property tables (Property Analysis) Tray properties (RadFrac, MultiFrac, etc.) Heating/cooling curves (Flash2, MHeatX, etc.)



Properties included in Prop-Sets• Properties commonly included in property sets include:

VFRAC - Molar vapor fraction of a stream BETA - Fraction of liquid in a second liquid phase CPMX - Constant pressure heat capacity for a mixture MUMX - Viscosity for a mixture

• Available properties include: Thermodynamic properties of components in a mixture Pure component thermodynamic properties Transport properties Electrolyte properties Petroleum-related properties

Reference: Aspen Plus Physical Property Data Reference Manual,Chapter 4, Property Sets, has a complete list of properties that can beincluded in a property set.



Specifying Property Sets• Use the Properties Prop-Sets form to specify properties in

a property set.

• The Search button can be used to search for a property.

• All specified qualifiers apply to each property specified,where applicable.

• Users can define new properties on the PropertiesAdvanced User-Properties form by providing a Fortransubroutine.



Predefined Property SetsSome simulation Templates contain predefined propertysets.

The following table lists predefined property sets and thetypes of properties they contain for the General Template:

Predefined Property Set Types of Properties

HXDESIGN Heat exchanger design

THERMAL Mixture thermal (HMX, CPMX,KMX)

TXPORT Transport

VLE Vapor-liquid equilibrium(PHIMX, GAMMA, PL)

VLLE Vapor-liquid-liquid equilibrium



Stream Results Options

• On the Setup Report Options Stream sheet, use: Flow Basis and Fraction Basis check-boxes to

specify how stream composition is reported Property Sets button to specify names of property

sets containing additional properties to be reported foreach stream



Definition of Terms• Property Method - Set of property models and methods

used to calculate the properties required for a simulation

• Property - Calculated physical property value such asmixture enthalpy

• Property Model - Equation or equations used tocalculate a physical property

• Property Parameter - Constant used in a property model

• Property Set (Prop-Set) - A method of accessingproperties so that they can be used or tabulatedelsewhere



Physical Properties WorkshopObjective: Simulate a two-liquid phase settling tank andinvestigate the physical properties of the system.

A refinery has a settling tank that they use to decant off the water from amixture of water and a heavy oil. The inlet stream to the tank alsocontains some carbon-dioxide and nitrogen. The tank and feed are atambient temperature and pressure (70o F, 1atm), and have the followingflow rates of the various components:

Water 515 lb/hrOil 4322 lb/hrCO2 751 lb/hrN2 43 lb/hr

Use the compound n-decane to represent the oil. It is known that waterand oil form two liquid phases under the conditions in the tank.



Physical Properties Workshop (Continued)

1. Choose an appropriate Property Method to represent this system.Check to see that the required binary physical property parametersare available.

2. Using the property analysis feature, verify that the chosen physicalproperty model and the available parameters predict the formationof 2 liquid phases.

3. Set up a simulation to model the settling tank. Use a Flash3 blockto represent the tank.

4. Modify the stream report to include the constant pressure heatcapacity (CPMX) for each phase (Vapor, 1st Liquid and 2nd Liquid),and the fraction of liquid in a second liquid phase (BETA), for allstreams.

5. Retrieve the physical property parameters used in the simulationand determine the critical temperature for carbon dioxide and water.

TC(carbon dioxide) = _______; TC(water) = _______




Optional Part:

Objective: Generate a table of compositions for each liquidphase (1st Liquid and 2nd Liquid) at different temperaturesfor a mixture of water and oil. Tabulate the vapor pressure ofthe components in the same table.• In addition to the interactive Analysis commands under the Tools

menu, you also can create a Property Analysis manually, using forms.• Manually generated Properties Analyses are created using the

Properties Analysis Object Manager.• Manually created Property Analyses can be executed at the end of a

flowsheet simulation or as a stand-alone run using a Run-Type ofProperty Analysis.

• A manually generated Generic Property Analysis is similar to theinteractive Analysis commands, however it is more flexible regardinginput and reporting.Detailed instructions are on the following slide.




Problem Specifications:

1. Create a Generic type property analysis.

2. Generate points along a flash curve.

3. Define component flows of 50 mole water and 50 mole oil.

4. Set Valid phases to Vapor-liquid-liquid.

5. Vary the temperature from 50 to 400 F.

6. Use a vapor fraction of zero.

7. Tabulate a new property set that includes:

a. Mole fraction of water and oil in the 1st and 2nd liquid phasesb. Mole flow of water and oil in the 1st and 2nd liquid phasesc. Beta - the fraction of the 1st liquid to the total liquidd. Pure component vapor pressures of water and oil


Potential

Reach Your

True


Accessing Variables

Objective:

Become familiar with referencing flowsheet variables

Aspen Plus References:• User Guide, Chapter 18, Accessing Flowsheet Variables

Related Topics:• User Guide, Chapter 20, Sensitivity• User Guide, Chapter 21, Design Specifications• User Guide, Chapter 19, Fortran Blocks and In-Line Fortran• User Guide, Chapter 22, Optimization• User Guide, Chapter 23, Fitting a Simulation Model to Data



• What is the effect of the reflux ratio of the column on thepurity (mole fraction of component B) of the distillate?

• To perform this analysis, references must be made to 2flowsheet quantities, i.e. 2 flowsheet variables must beaccessed:1. The reflux ratio of the column2. The mole fraction of component B in the stream

OVHD

Why Access Variables?

COLUMNFEED

OVHD

BTMS



Accessing Variables• An accessed variable is a reference to a particular

flowsheet quantity, e.g. temperature of a stream or duty ofa block.

• Accessed variables can be read from, written to, or both.

• Flowsheet result variables (calculated quantities) shouldnot be overwritten or varied.

• The concept of accessing variables is used in sensitivityanalyses, design specifications, in-line Fortran,optimization, etc.



Variable Categories

Variable Category Type of Variable Blocks Block variables and vectors

Streams Stream variables and vectors.Both non-component variables andcomponent dependent flow and compositionvariables can be accessed.

Model Utility Parameters, balance block and pressurerelief variables

Property Property parameters

Reactions Reactions and chemistry variables

Costing Costing variables



• When completing a Define sheet, such as on a Fortran,Design specification or Sensitivity form, specify thevariables on the Variable Definition dialog box.

• You cannot modify the variables on the Define sheet itself.

• On the Variable Definition dialog box, select the variablecategory and Aspen Plus will display the other fieldsnecessary to complete the variable definition.

• If you are editing an existing variable and want to changethe variable name, click the right mouse button on theVariable Name field. On the popup menu, click Rename.

Variable Definition Dialog Box



Notes1. If the Mass-Frac, Mole-Frac or StdVol-Frac of a component in

a stream is accessed, it should not be modified. To modify thecomposition of a stream, access and modify the Mass-Flow,Mole-Flow or StdVol-Flow of the desired component.

2. If duty is specified for a block, that duty can be read and writtenusing the variable DUTY for that block. If the duty for a block iscalculated during simulation, it should be read using thevariable QCALC.

3. PRES is the specified pressure or pressure drop, and PDROPis pressure drop used in calculating pressure profile in heatingor cooling curves.

4. Only streams that are feeds to the flowsheet should be variedor modified directly.


Potential

Reach Your

True


Sensitivity Analysis

Objective:Introduce the use of sensitivity analysis to studyrelationships between process variables

Aspen Plus References:• User Guide, Chapter 20, Sensitivity

Related Topics:• User Guide, Chapter 18, Accessing Flowsheet Variables• User Guide, Chapter 19, Fortran Blocks and In-Line Fortran



Sensitivity Analysis• Allows user to study the effect of changes in input

variables on process outputs.

• Results can be viewed by looking at the Results form inthe folder for the Sensitivity block.

• Results may be graphed to easily visualize relationshipsbetween different variables.

• Changes made to a flowsheet input quantity in asensitivity block do not affect the simulation. Thesensitivity study is run independently of the base-casesimulation.

• Located under /Data/Model Analysis Tools/Sensitivity



Sensitivity Analysis Example

What is the effect of cooler outlet temperature on the purityof the product stream?

• What is the manipulated (varied) variable?

• What is the measured (sampled) variable?

Filename: CUMENE-S.BKP

» Cooler outlet temperature

» Purity (mole fraction) of cumene in product stream

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUT SEP

PRODUCT



Sensitivity S-1 Results Summary

VARY 1 COOL PARAM TEMP F50 75 100 125 150 175 200 225 250 275 300 325 350

CU

ME

NE

PR

OD

UC

T P

UR

ITY

0.85

0.9

0.95

1

Sensitivity Analysis Results

• What is happening below 75 F and above 300 F?



Uses of Sensitivity Analysis• Studying the effect of changes in input variables on

process (model) outputs

• Graphically representing the effects of input variables

• Verifying that a solution to a design specification isfeasible

• Rudimentary optimization

• Studying time varying variables using a quasi-steady-state approach



Steps for Using Sensitivity Analysis1. Specify measured (sampled) variable(s)

These are quantities calculated during the simulation tobe used in step 4 (Sensitivity Input Define sheet).

2. Specify manipulated (varied) variable(s) These are the flowsheet variables to be varied

(Sensitivity Input Vary sheet).

3. Specify range(s) for manipulated (varied) variable(s) Variation for manipulated variable can be specified either

as equidistant points within an interval or as a list ofvalues for the variable (Sensitivity Input Vary sheet).

4. Specify quantities to calculate and tabulate Tabulated quantities can be any valid Fortran expression

containing variables defined in step 1 (Sensitivity InputTabulate sheet).



Plotting

1. Select the column containing the X-axis variable and thenselect X-Axis Variable from the Plot menu.

2. Select the column containing the Y-axis variable and thenselect Y-Axis Variable from the Plot menu.

3. (Optional) Select the column containing the parametricvariable and then select Parametric Variable from thePlot menu.

4. Select Display Plot from the Plot menu.

» To select a column, click on the heading of the columnwith the left mouse button.



Notes

1. Only quantities that have been input to the flowsheetshould be varied or manipulated.

2. Multiple inputs can be varied.

3. The simulation is run for every combination ofmanipulated (varied) variables.



Sensitivity Analysis Workshop

Part A:Using the cyclohexane production flowsheet Workshop (saved asCYCLOHEX.BKP), plot the variation of reactor duty (block REACT) asthe recycle split fraction in LFLOW is varied from 0.1 to 0.4.

Optional Part B:In addition to the fraction split off as recycle (Part A), vary theconversion of benzene in the reactor from 0.9 to 1.0. Tabulate thereactor duty and construct a parametric plot showing the dependence ofreactor duty on the fraction split off as recycle and conversion ofbenzene.

Note: Both of these studies (parts A and B) should be set up within thesame sensitivity analysis block.

When finished, save as filename: SENS.BKP.

Objective: Use a sensitivity analysis to study the effect ofthe recycle flowrate on the reactor duty in the cyclohexaneflowsheet






P = 25 barT = 50 C

Molefrac H2 = 0.975N2 = 0.005CH4 = 0.02



T = 150CP = 23 bar T = 200 C


0.998







REACTFEED-MIXH2IN

BZIN

H2RCY

CHRCY

RXIN

RXOUT

HP-SEP

VAP

COLUMN

COLFD

LTENDS

PRODUCT

VFLOW

PURGE

LFLOW

LIQ


Potential

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True


Design Specifications

Objective:Introduce the use of design specifications to meet processdesign requirements

Aspen Plus References:•User Guide, Chapter 21, Design Specifications

Related Topics:•User Guide, Chapter 18, Accessing Flowsheet Variables•User Guide, Chapter 19, Fortran Blocks and In-Line Fortran•User Guide, Chapter 17, Convergence



Design Specifications• Similar to a feedback controller

• Allows user to set the value of a calculated flowsheetquantity to a particular value

• Objective is achieved by manipulating a specified inputvariable

• No results associated directly with a design specification

• Located under /Data/Flowsheeting Options/Design Specs



Design Specification Example

What should the cooler outlet temperature be to achieve acumene product purity of 98 mole percent?

• What is the manipulated (varied) variable?

• What is the measured (sampled) variable?

• What is the specification (target) to be achieved?

Filename: CUMENE-D.BKP

» Cooler outlet temperature

» Mole fraction of cumene in stream PRODUCT

» Mole fraction of cumene in stream PRODUCT = 0.98

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUT SEP

PRODUCT



Steps for Using Design Specifications1. Identify measured (sampled) variables

These are flowsheet quantities, usually calculatedquantities, to be included in the objective function(Design Spec Define sheet).

2. Specify objective function (Spec) and goal (Target)This is the equation that the specification attempts tosatisfy (Design Spec Spec sheet). The units of thevariable used in the objective function are the units forthat type of variable as specified by the Units Setdeclared for the design specification.

3. Set tolerance for objective functionThe specification is said to be converged if the objectivefunction equation is satisfied to within this tolerance(Design Spec Spec sheet).



Steps for Using Design Specifications (Continued)

4. Specify manipulated (varied) variableThis is the variable whose value the specificationchanges in order to satisfy the objective functionequation (Design Spec Vary sheet).

5. Specify range of manipulated (varied) variableThese are the lower and upper bounds of the intervalwithin which Aspen Plus will vary the manipulatedvariable (Design Spec Vary sheet). The units of thelimits for the varied variable are the units for that type ofvariable as specified by the Units Set declared for thedesign specification.



Notes1. Only quantities that have been input to the flowsheet

should be manipulated.

2. The calculations performed by a design specification areiterative. Providing a good estimate for the manipulatedvariable will help the design specification converge infewer iterations. This is especially important for largeflowsheets with several interrelated design specifications.

3. The results of a design specification can be found underData/Convergence/Convergence, by opening theappropriate solver block, and choosing the Results form.Alternatively, the final values of the manipulated and/orsampled variables can be viewed directly on theappropriate Stream/Block results forms.



Notes (Continued)

4. If a design-spec does not converge:

a. Check to see that the manipulated variable is not atits lower or upper bound.

b. Verify that a solution exists within the boundsspecified for the manipulated variable, perhaps byperforming a sensitivity analysis.

c. Check to ensure that the manipulated variable doesindeed affect the value of the sampled variables.

d. Try providing a better starting estimate for the valueof the manipulated variable.



Notes (Continued)

e. Try changing the characteristics of the convergenceblock associated with the design-spec (step size,number of iterations, algorithm, etc.)

f. Try narrowing the bounds of the manipulated variableor loosening the tolerance on the objective functionto help convergence.

g. Make sure that the objective function does not have aflat region within the range of the manipulatedvariable.



Design Specification Workshop

The cyclohexane production flowsheet workshop (saved asCYCLOHEX.BKP) is a model of an existing plant. The cooling systemaround the reactor can handle a maximum operating load of 4.7MMkcal/hr. Determine the amount of cyclohexane recycle necessary tokeep the cooling load on the reactor to this amount.

Note: The heat convention used in Aspen Plus is that heat input to ablock is positive, and heat removed from a block is negative.

When finished, save as filename: DES-SPEC.BKP

Objective: Use a design specification in the cyclohexaneflowsheet to fix the heat load on the reactor by varying therecycle flowrate.






P = 25 barT = 50 C

Molefrac H2 = 0.975N2 = 0.005CH4 = 0.02



T = 150CP = 23 bar T = 200 C


0.998







REACTFEED-MIXH2IN

BZIN

H2RCY

CHRCY

RXIN

RXOUT

HP-SEP

VAP

COLUMN

COLFD

LTENDS

PRODUCT

VFLOW

PURGE

LFLOW

LIQ


Potential

Reach Your

True


Fortran Blocks

Objective:

Introduce usage of Fortran blocks in Aspen Plus

Aspen Plus References:•User Guide, Chapter 19, Fortran Blocks and In-Line Fortran

Related Topics:•User Guide, Chapter 20, Sensitivity•User Guide, Chapter 21, Design Specifications•User Guide, Chapter 18, Accessing Flowsheet Variables•User Guide, Chapter 22, Optimization



Fortran Blocks• Allows user to write Fortran to be executed by Aspen Plus

• Simple Fortran can be translated by Aspen Plus and doesnot need to be compiled.

• A Fortran compiler must be present on the machine wherethe Aspen Plus engine is running to compile morecomplex Fortran code.

• Results of the execution of a Fortran block must beviewed by directly examining the values of the variablesmodified by the Fortran block.

• Located under /Data/Flowsheeting Options/Fortran



Fortran Block ExampleUse of a Fortran block to set the pressure drop across aHeater block.

Pressure drop across heater is proportional to square ofvolumetric flow into heater.

Fortran BlockDELTA-P = -10-9 * V2

V

Filename: CUMENE-F.BKP

DELTA-P

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUT SEP

PRODUCT



Fortran Block Example (Continued)

• Which flowsheet variables must be accessed?

• When should the Fortran block be executed?

• Which variables are read and which are written?

» Volumetric flow of stream REAC-OUTThis can be accessed in two different ways:1. Mass flow and mass density of stream REAC-OUT2. A prop-set containing volumetric flow of a mixture

» Pressure drop across block COOL

» Before block COOL

» Volumetric flow is read» Pressure drop is written



Uses of Fortran Blocks• Feed-forward control (setting flowsheet inputs based on

upstream calculated values)

• Calling external subroutines

• Input / output to and from external files

• Writing to Control Panel, History File, or Report File

• Custom reports



Fortran Interpreter

• Aspen Plus will interpret in-line Fortran if it is possible.

• The following Fortran can be interpreted:Arithmetic expressions and assignment statementsIF statementsGOTO statements, except assigned GOTOWRITE statements that do not have unformatted text in themFORMAT statementsCONTINUE statementsDO loopsCalls to some built-in Fortran functionsREAL or INTEGER statements*DOUBLE PRECISION statements*DIMENSION statements** Enter on the Declaration sheet.



Built-In Fortran Functions

• Calls to some built-in Fortran functions:DABS DERF DMIN1 IDINTDACOS DEXP DMOD MAX0DASIN DFLOAT DSIN MIN0DATAN DGAMMA DSINH MODDATAN2 DLGAMA DSQRTDCOS DLOG DTANDCOSH DLOG10 DTANHDCOTAN DMAX1 IABS

• You can also use the equivalent single precision orgeneric function names. But, Aspen Plus alwaysperforms double precision calculations.



Statements Requiring Compilation

• The following statements require compilation:CALL LOGICALCHARACTER PARAMETERCOMMON PRINTCOMPLEX RETURNDATA READENTRY STOPEQUIVALENCE SUBROUTINEIMPLICIT



Steps for Using Fortran Blocks1. Access flowsheet variables to be used within Fortran

All flowsheet quantities that must be either read fromor written to, must be identified (Fortran Input Definesheet).

2. Write Fortran Includes both non-executable (COMMON,

EQUIVALENCE, etc) Fortran (Fortran InputDeclarations sheet) and executable Fortran (FortranInput Fortran sheet) to achieve desired result.

3. Specify location of Fortran block in execution sequence(Fortran Input Sequence sheet) Specify directly, or Specify with read and write variables



Notes1. Only quantities that have been input to the flowsheet

should be overwritten.

2. The rules for writing In-Line Fortran are as follows:

a. The Fortran code must begin in column 7 or beyond.b. Comment lines must have the letter “C” or a “ ; ” in

the first column.c. Column two must be blank.

3. Variable names should not begin with lZ or ZZ.



Notes (Continued)

4. On the Fortran Input Sequence sheet, the preferred wayto specify where the Fortran block should be executed isto list the read and write variables.

5. When using the Fortran WRITE statement, you can usethe predefined unit number NTERM to write to the controlpanel. For example,

write(NTERM,*) flow

OR

write(NTERM,10) flow 10 format(‘Feed flowrate =‘,G12.5)



Fortran Workshop

In a methane reformer, hydrogen gas is produced by reacting methanewith water, generating carbon monoxide as a by-product. The reactiontaking place is the following:

The feed to the reformer consists of pure methane and water streams.These are mixed and heated prior to being fed to the reformer. Theconversion of methane is 99.5%, and the molar ratio of methane towater in the feed is 1:4.

Create a flowsheet as shown in the diagram on the following slide. Setup a Sensitivity block and plot a graph showing the variation of reactorduty as the methane flowrate in the feed is varied from 100 to 500lbmol/hr.

Note: The methane:water ratio in the feed must be maintainedconstant for each Sensitivity case. (Hint: This can beachieved using a Fortran Block.)

Objective: Use a Fortran Block to maintain the methane:waterratio in the feed to a reactor.



Fortran Workshop (Continued)

CH4 + H2O = 3 H2 + CO

Methane Water Hydrogen Carbon Monoxide

Temperature = 150 F

Pressure = 900 psia

Temperature = 70 F

Pressure = 15 psiaTemperature = 1100 F

Pressure = 850 psiaTemperature = 1450 F

Pressure Drop = 20 psi

CH4 conversion = 0.995

Use the Peng-Robinson Property Method

When finished, save asfilename: Fortran.BKP

MIXCH4

H2O

RXIN

REFORMER

RXOUT


Potential

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True


Windows Interoperability

Objective:

Introduce the use of windows interoperability to transferdata easily to and from other Windows programs.

Aspen Plus References:• User Guide, Chapter 37, Working with Other Windows Programs• User Guide, Chapter 38, Using the Aspen Plus ActiveX Automation

Server




• Copying and pasting simulation data into spreadsheetsor reports

• Copying and pasting flowsheet graphics and plots intoreports

• Creating active links between Aspen Plus and otherWindows applications

• OLE embedding

• ActiveX automation



Windows Interoperability - Examples• Copy simulation results such as column profiles and

stream results into Spreadsheet for further analysis Word processor for reports and documentation Design program Database for case storage and management

• Copy flowsheet graphics and plots into Word processor for reports Slide making program for presentations

• Copy tabular data from spreadsheets into Aspen Plusfor Data Regression, Data-Fit, etc.

• Copy plots or tables into the Process FlowsheetWindow.



Benefits of Windows Interoperability

• Benefits of Copy/Paste/Paste Link Live data links can be established that update these

applications as the process model is changed toautomatically propagate results of engineeringchanges.

The benefits to the engineer are quick and error-freedata transfer and consistent engineering resultsthroughout the engineering work process.



Steps for Using Copy and Paste

1. Select Select the data fields or the graphical objects.

Multiple fields of data or objects can be selected byholding down the CTRL key while clicking the mouseon the fields.

Columns of data can be selected by clicking thecolumn heading, or an entire grid can be selected byclicking on the top left cell.

2. Copy Choose Copy from the Edit menu or type CTRL-C.

3. Paste Click the mouse in the input field where you want the

information and choose Paste from the Edit menu orclick CTRL-V.



OLE Embedding

• What is OLE embedding? Applications can be used within applications.

• Uses of OLE embedding Aspen Plus as the OLE server: Aspen Plus

flowsheet graphics can be embedded into a reportdocument, or stream data into a CAD drawing. Thesimulation model is actually contained in thedocument, and could be delivered directly with thatdocument.

Aspen Plus as the OLE container: Other windowsapplications can be embedded within the AspenPlus simulation.



OLE Embedding (Continued)

• Examples of OLE embedding OLE server: If the recipient of an engineering report,

for example, wanted to review the modelassumptions, he could access and run theembedded Aspen Plus model directly from the reportdocument.

OLE container: For example, Excel spreadsheetsand plots could be used to enhance Aspen Plusflowsheet graphics.



Embedding Objects in the Flowsheet

• You can embed other applications as objects into theProcess Flowsheet window.

• You can do this in two ways: Using Copy and Paste Using the Insert dialog box

• You can edit the object embedded in the flowsheet bydouble clicking on the object to edit it inside Aspen Plus.

• You can also move, resize or attach the object to a blockor stream in the flowsheet.



Copy and Paste Workshop 1

• Use the Cyclohexane flowsheet workshop (saved asCYCLOHEX.BKP)

• Copy the temperature profile from COLUMN into aspreadsheet.

• Generate a plot of the temperature using the plot wizardand copy and paste the plot into the spreadsheet.

• Save the spreadsheet as CYCLOHEX-result.xls

Objective: Use copy and paste to copy and paste thestage temperatures into a spreadsheet.



Copy and Paste Workshop 2


• Copy the stream results from stream RXIN into the inputform. Copy the compositions, the temperature and the

pressure separately.

Note: Reinitialize before running the simulation in order tosee how many iterations are needed before and after theestimate is added.

Objective: Use copy and paste to copy the streamresults to a stream input form.



Creating Active Links

• When copying and pasting information, you can createactive links between input or results fields in AspenPlus and other applications such as Word and Excel.

• The links update these applications as the processmodel is modified to automatically propagate results ofengineering changes.



Steps for Creating Active Links

1. Open both applications.

2. Select the data (or object) that you want to paste andlink.

3. Choose Copy from the Edit menu.

4. In the location where you want to paste the link, choosePaste Special from the Edit menu.

5. In the Paste Special dialog box, click the Paste Linkradio button.



Paste Link Demonstration

Objective: Create an active link from Aspen PlusResults into a spreadsheet.

• Start with the cumene flowsheet demonstration.

• Open a spreadsheet and create a cell with thetemperature for the cooler in it.

• Copy and paste the link into the Aspen Plus flowsheet.

• Copy and paste a link with the flow and composition ofcumene in the product stream into the spreadsheet.

• Change the temperature in the spreadsheet and thenrerun the flowsheet. Notice the changes.



Paste Link WorkshopObjective: Create an active link from Aspen Plus results

into a spreadsheet


• Copy the Condenser and Reboiler duty results from theRadFrac COLUMN Summary sheet. Use Copy with Formatand copy the value, the label and the units.

• Paste the results into the CYCLOHEX-results.xls spreadsheetas a link. Use Paste Special and choose Link.

• Change the Reflux ratio in the column to 2 and rerun theflowsheet. Check the spreadsheet to see that the results havechanged there also. Notice that the temperature profile resultshave not changed since they were not pasted as a link.



Saving Files with Active Links

• Be sure to save both the link source file and the linkcontainer file.

• If you save the link source with a different name, youmust save the link container after saving the linksource.

• If you have active links in both directions between thetwo applications and you change the name of both files,you must do three Save operations: Save the first application with a new name. Save the second application with a new name. Save the first application again.



Running Files with Active Links

• When you open the link source file, there is nothingspecial that you need to do.

• When you open the link container file, you will usuallysee a dialog box asking you if you want to re-establishthe links. You can select Yes or No.

• To make a link source application visible: Select Links, from the Edit menu in Aspen Plus. In the Links dialog box, select the source file and

click Open Source.(Note: The Process Flowsheet must be the activewindow. Links is not an option on the Edit menu ifthe Data Browser is active.)



ActiveX Automation

• What is ActiveX automation? Other programs such as Visual Basic or C++ can be

used to control a simulation.

• Uses of ActiveX automation Visual Basic or C++ can be written to access and

control process models using a documentedinterface syntax.

Custom applications can be built on top of processmodels.



OLE Automation (Continued)

• Benefits of ActiveX automation A model developer in the Process Engineering

department could develop a customized Excelinterface to an Aspen Plus model for plant operators,using the Visual Basic for Applications (VBA) macrolanguage.

A customer might write a top-level C++ program that• pulls data from a process model• uses that data to automatically generate custom

spec sheets• populates a process engineering database• launches a third-party design program



OLE Automation Demonstration

• Demonstration 1 Simple run and reinit button are used in the butanol

flowsheet. Files: butanol-demo.xls and butanol.bkp

• Demonstration 2 More elaborate Visual Basic code is used to create a

general heat exchanger spreadsheet that canaccess the heat exchangers in any Aspen Plusflowsheet.

Files: olespecsheet.xls and heatx2.bkp



Visual Basic Examples

» Located in the APUI100\VBExample directory

• Open - open existing simulation• Run - changes a simulation parameter and re-runs the simulation• ListBlocks - retrieves a list of blocks and their attributes• Connectivity - displays a table showing flowsheet connectivity• GetCollection - illustrates use of a collection object• GetScalarValues - retrieves scalar variables from a block• TempProf - retrieves values for a non-scalar variable with one identifier• CompProf - retrieves values for a non-scalar variable with two identifiers• ReacCoeff - retrieves values for a non-scalar variable with three identifiers• UnitChange - shows changing the units of measurement of a variable• UnitConversion - retrieves a value both in the display units (psi) and

alternative units (atm)• UnitString - retrieves the units of measurement symbol for a variable


Potential

Reach Your

True


Heat Exchangers

Objective:

Introduce the unit operation models used for heatexchangers and heaters.

Aspen Plus References:• Unit Operation Models Reference Manual, Chapter 3,

Heat Exchangers



Heat Exchanger Blocks

• Heater - Heater or cooler

• HeatX - Two stream heat exchanger

• MHeatX - Multi-stream heat exchanger

• Hetran - Interface to B-JAC Hetran block

• Aerotran - Interface to B-JAC Aerotran block



Working with the Heater Model

The Heater block mixes multiple inlet streams to produce asingle outlet stream at a specified thermodynamic state.

Heater can be used to represent: Heaters Coolers Valves Pumps (when work-related results are not needed) Compressors (when work-related results are not

needed)

Heater can also be used to set the thermodynamic conditionsof a stream.



Heater Input Specifications

Allowed combinations:

• Pressure (or Pressure drop) and one of: Outlet temperature Heat duty or inlet heat stream Vapor fraction Temperature change Degrees of subcooling or superheating

• Outlet Temperature or Temperature change and one of: Pressure Heat Duty Vapor fraction



Heater Input Specifications (Continued)

For single phase use Pressure (drop) and one of: Outlet temperature Heat duty or inlet heat stream Temperature change

Vapor fraction of 1 means dew point condition, 0 means bubble point



Heat Streams

• Any number of inlet heat streams can be specified for aHeater.

• One outlet heat stream can be specified for the net heatload from a Heater.

• The net heat load is the sum of the inlet heat streamsminus the actual (calculated) heat duty.

• If you give only one specification (temperature orpressure), Heater uses the sum of the inlet heatstreams as a duty specification.

• If you give two specifications, Heater uses the heatstreams only to calculate the net heat duty.



Working with the HeatX Model

• HeatX can perform simplified or rigorous ratingcalculations.

• Simplified rating calculations (heat and materialbalance calculations) can be performed if exchangergeometry is unknown or unimportant.

• For rigorous heat transfer and pressure dropcalculations, the heat exchanger geometry must bespecified.



Working with the HeatX Model (Continued)

HeatX can model shell-and-tube exchanger types: Counter-current and co-current Segmental baffle TEMA E, F, G, H, J and X shells Rod baffle TEMA E and F shells Bare and low-finned tubes

HeatX performs: Full zone analysis Heat transfer and pressure drop calculations Sensible heat, nucleate boiling, condensation

film coefficient calculations Built-in or user specified correlations



Working with the HeatX Model (Continued)

HeatX cannot:

• Perform design calculations

• Perform mechanical vibration analysis

• Estimate fouling factors



HeatX Input Specifications

Select one of the following specifications:

• Heat transfer area or Geometry

• Exchanger duty

• For hot or cold outlet stream: Temperature Temperature change Temperature approach Degrees of superheating / subcooling Vapor fraction



Working with the MHeatX Model

• MHeatX can be used to represent heat transferbetween multiple hot and cold streams.

• Detailed, rigorous internal zone analysis can beperformed to determine pinch points.

• MHeatX uses multiple Heater blocks and heat streamsto enhance flowsheet convergence.

• Two-stream heat exchangers can also be modeledusing MHeatX.



HeatX versus Heater

Consider the following:

• Use HeatX when both sides are important.

• Use Heater when one side (e.g. the utility) is notimportant.

• Use two Heaters (coupled by heat stream, Fortranblock or design spec) or an MHeatX to avoid flowsheetcomplexity created by HeatX.



Two Heaters versus One HeatX



Working with Hetran and Aerotran

• The Hetran block is the interface to the B-JAC Hetranprogram for designing and simulating shell and tubeheat exchangers.

• The Aerotran block is the interface to the B-JACAerotran program for designing and simulating air-cooled heat exchangers.

• Information related to the heat exchanger configurationand geometry is entered through the Hetran or Aerotranstandalone program interface.



Heat Curves

All of the heat exchanger models are able to calculateHeat Curves (Hcurves).

Tables can be generated for various independentvariables (typically duty or temperature) for anyproperty that Aspen Plus can generate.

These tables can be printed, plotted, or exported for usewith other heat exchanger design software.



Heat Curves Tabular Results



Heat Curve Plot



HeatX Workshop

• Hydrocarbon stream Temperature: 200 C Pressure: 4 bar Flowrate: 10000 kg/hr Composition: 50 wt% benzene, 20% styrene,

20% ethylbenzene and 10% water

• Cooling water Temperature: 20 C Pressure: 10 bar Flow rate: 60000 kg/hr Composition: 100% water

Objective: Compare the simulation of a heat exchangerthat uses water to cool a hydrocarbon mixture using threemethods: a shortcut HeatX, a rigorous HeatX and twoHeaters connected with a Heat stream.



HeatX Workshop (Continued)

RHEATX

RHOT-IN

RCLD-IN RCLD-OUT

RHOT-OUT

SHEATX

SHOT-IN

SCLD-IN SCLD-OUT

SHOT-OUT

HEATER-1

HCLD-IN

Q-TRANS

HCLD-OUT

HEATER-2

HHOT-IN HHOT-OUT

Use the NRTL-RK Property Method for the hydrocarbon streams.

Specify that the valid phases for the hydrocarbon stream is Vapor-Liquid-Liquid.

Specify that the Steam Tables are used to calculate the properties for the cooling water streams on the Block BlockOptions Properties sheet.

Start with the General with Metric Units Template.

When finished, save as filename: HEATX.BKP



HeatX Workshop (Continued)

• Shortcut HeatX simulation: Hydrocarbon stream exit has a vapor fraction of 0 No pressure drop in either stream

• Two Heaters simulation: Use the same specifications as the shortcut HeatX simulation

• Rigorous HeatX simulation: Hydrocarbons in shell leave with a vapor fraction of 0 Shell diameter 1 m, 1 tube pass 300 bare tubes, 3 m length, pitch 31 mm, 21 mm ID, 25 mm OD All nozzles 100 mm 5 baffles, 15% cut Create heat curves containing all info required for thermal design. Change the heat exchanger specification to Geometry and re-run.


Potential

Reach Your

True


Pressure Changers

Objective:

Introduce the unit operation models used to changepressure: pumps, compressors, and models forcalculating pressure change through pipes and valves.

Aspen Plus References:• Unit Operation Models Reference Manual, Chapter 6, Pressure

Changers



Pressure Changer Blocks

• Pump - Pump or hydraulic turbine

• Compr - Compressor or turbine

• MCompr - Multi-stage compressor or turbine

• Valve - Control valve

• Pipe - Single-segment pipe

• Pipeline - Multi-segment pipe



Working with the Pump Model

• The Pump block can be used to simulate: Pumps Hydraulic turbines

• Power requirement is calculated or input.

• A Heater model can be used for pressure changecalculations only.

• Pump is designed to handle a single liquid phase.

• Vapor-liquid or vapor-liquid-liquid calculations can bespecified to check outlet stream phases.



Pump Performance Curves

• Rating can be done by specifying scalar parameters ora pump performance curve.

• Specify: Dimensional curves

• Head versus flow• Power versus flow

Dimensionless curves:• Head coefficient versus flow coefficient



Working with the Compr Model

• The Compr block can be used to simulate: Polytropic centrifugal compressor Polytropic positive displacement compressor Isentropic compressor Isentropic turbine

• MCompr is used for multi-stage compressors.

• Power requirement is calculated or input.

• A Heater model can be used for pressure changecalculations only.

• Compr is designed to handle both single and multiplephase calculations.



Working with the MCompr Model

• The MCompr block can be used to simulate: Multi-stage polytropic centrifugal compressor Multi-stage polytropic positive displacement compressor Multi-stage isentropic compressor Multi-stage isentropic turbine

• MCompr can have an intercooler between each stage, andan aftercooler after the last stage. You can perform one-, two-, or three- phase flash

calculations in the intercoolers. Each cooler can have a liquid knockout stream, except

the cooler after the last stage. Intercooler specifications apply to all subsequent

coolers.



Compressor Performance Curves

• Rating can be done by specifying a compressorperformance curve.

• Specify: Dimensional curves

• Head versus flow• Power versus flow

Dimensionless curves:• Head coefficient versus flow coefficient

• Compr cannot handle performance curves for a turbine.



Work Streams

• Any number of inlet work streams can be specified forpumps and compressors.

• One outlet work stream can be specified for the network load from pumps or compressors.

• The net work load is the sum of the inlet work streamsminus the actual (calculated) work.



Working with the Valve Model

• The Valve block can be used to simulate: Control valves Pressure drop

• The pressure drop across a valve is related to the valveflow coefficient.

• Flow is assumed to be adiabatic.

• Valve can perform single or multiple phase calculations.



Working with the Valve Model (Continued)

• The effect of head loss from pipe fittings can be included.

• There are three types of calculations: Adiabatic flash for specified outlet pressure (pressure

changer) Calculate valve flow coefficient for specified outlet

pressure (design) Calculate outlet pressure for specified valve (rating)

• Valve can check for choked flow.

• Cavitation index can be calculated.



Working with the Pipe Model

• The Pipe block calculates the pressure drop and heattransfer in a single pipe segment.

• The Pipeline block can be used for a multiple-segmentpipe.

• Pipe can perform single or multiple phase calculations.

• If the inlet pressure is known, Pipe calculates the outletpressure.

• If the outlet pressure is known, Pipe calculates the inletpressure and updates the state variables of the inletstream.

• Entrance effects are not modeled.



Pressure Changers Block ExampleAdd a Compressor and a Valve to the cumene flowsheet.

Filename: CUMENE-P.BKP

REACTOR

FEED

RECYCLE

REAC-OUT

COOL

COOL-OUTSEP

PRODUCT

COMPR

RECYCLE2

VALVE

RECYCLE3 Outlet Pressure = 3 psig

Polytropic compressor model using GPSA methodDischarge pressure = 5 psig



Pressure Changers Workshop

• Start with the Cyclohexane Workshop flowsheet(CYCLOHEX.BKP)

Objective: Add pressure changer unit operations to theCyclohexane flowsheet.



Pressure Changers Workshop (Continued)

FEED-MIX

H2IN

CHRCY3

H2RCY2

BZIN2

RXIN

REACT

RXOUTHP-SEP

LIQ

VAP

COLUMN

COLFD

LTENDS

PRODUCT

VFLOWH2RCY

PURGE

LFLOW

CHRCY

PUMPCHRCY2

PIPE

COMP

FEEDPUMP

BZIN

VALVE

PURGE2

When finished, save asfilename: PRESCHNG.BKP

Pump efficiency = 0.6Driver efficiency = 0.9

Performance CurveHead Flow[m] [cum/hr]40 20250 10300 5400 3

Carbon SteelSchedule 401-in diameter25-m length

26 bar outlet pressure

20 bar outlet pressureGlobe valveV810 equal percent flow1.5-in size

Isentropic4 bar pressure change


Potential

Reach Your

True


Flowsheet Convergence

Objective:

Introduce the idea of convergence blocks, tear streamsand flowsheet sequences

Aspen Plus References:•User Guide, Chapter 17, Convergence



Convergence Blocks• Every design specification and tear stream has an

associated convergence block.

• Convergence blocks determine how guesses for a tearstream or design specification manipulated variable areupdated from iteration to iteration.

• Aspen Plus-defined convergence block names begin withthe character “$.” User defined convergence block names must not begin

with the character “$.”

• To determine the convergence blocks defined by AspenPlus, look under the “Flowsheet Analysis” section in theControl Panel messages.

• User convergence blocks can be specified under/Data/Convergence/Convergence...



Convergence Block Types• Different types of convergence blocks are used for different

purposes:To converge tear streams:

• WEGSTEIN• DIRECT• BROYDEN• NEWTON

To converge design specifications:• SECANT• BROYDEN• NEWTON

To converge design specifications and tear streams:• BROYDEN• NEWTON

For optimization:• SQP• COMPLEX

• Global convergence options can be specified on the ConvergenceConvOptions Defaults form.



Flowsheet Sequence• To determine the flowsheet sequence calculated by

Aspen Plus, look under the “COMPUTATION ORDERFOR THE FLOWSHEET” section in the Control Panel, oron the left-hand pane of the Control Panel window.

• User-determined sequences can be specified on theConvergence Sequence form.

• User-specified sequences can be either full or partial.



Tear Streams• Which are the recycle streams?

• Which are the possible tear streams?

• A tear stream is one for which Aspen Plus makes an initialguess, and iteratively updates the guess until twoconsecutive guesses are within a specified tolerance.

• Tear streams are related to, but not the same as recyclestreams.

S1 S2 S3

S6

S4

S7

S5MIXER

B1

MIXER

B2

FSPLIT

B3

FSPLIT

B4



Tear Streams (Continued)

• To determine the tear streams chosen by Aspen Plus,look under the “Flowsheet Analysis” section in the ControlPanel.

• User-determined tear streams can be specified on theConvergence Tear form.

• Providing estimates for tear streams can facilitate orspeed up flowsheet convergence (highly recommended,otherwise the default is zero).

• If you enter information for a stream that is in a “loop,”Aspen Plus will automatically try to choose that stream tobe a tear stream.



Reconciling Streams

• Simulation results for a stream can be copied onto theits input form.

• Select a stream on the flowsheet, click the right mousebutton and select “Reconcile” from the list to copystream results to the input form. Two state variables must be selected for the stream

flash calculation. Component flows, or component fractions and total

flow can be copied. Mole, mass, or standard liquid volume basis can be

selected.



Convergence WorkshopObjective: Converge this flowsheet. Start with the file CONVERGE.BKP.

LIQ

VAPOR

FEED-HT

FEED

BOT

DIST

BOT-COOL

GLYCOL

COLUMN

PREHEATR

PREFLASH

T=165 FP=15 psia

100 lbmol/hr

XH20 = 0.4XMethanol = 0.3XEthanol = 0.3

Area = 65 sqft

DP=0Q=0

Theoretical Stages = 10Reflux Ratio = 5Distillate to Feed Ratio = 0.2

Feed Stage = 5Column Pressure = 1 atm

Total Condenser

Use NRTL-RK Property Method

T=70 FP=35 psia50 lbmol/hr Ethylene Glycol

When finished, save asfilename: CONV-R.BKP



Convergence Workshop (Continued)

Hints for Convergence Workshop:

Questions to ask yourself: What messages are displayed in the control panel? Why do some of the blocks show zero flow? What is the Aspen Plus-generated execution sequence for the

flowsheet? Which stream does Aspen Plus choose as a tear stream? What are other possible tear streams?

Recommendation: Give initial estimates for a tear stream. Of the three possible tear streams you could choose, which do

you know the most about? (Note: If you enter information for astream that is in a “loop,” Aspen Plus will automatically choosethat stream to be a tear stream and set up a convergence blockfor it.)



Convergence Workshop (Continued)

Questions to ask yourself: Does the flowsheet converge after entering initial estimates for

the tear stream? If not, why not? (see control panel) How is the err/tol value behaving, and what is its value at the

end of the run? Does it appear that increasing the number of convergence

iterations will help? What else can be tried to improve this convergence?

Recommendation: Try a different convergence algorithm (e.g. Direct,Broyden, or Newton).

Note: You can either manually create a convergence block to convergethe tear stream of your choice, or you can change the defaultconvergence method for all tear streams on the ConvergenceConv Options Defaults Default Methods sheet.


Potential

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Full-Scale Plant Modeling Workshop

Objective:

Practice and apply many of the techniques used in thiscourse and learn how to best approach modelingprojects



Full-Scale Plant Modeling WorkshopObjective: Model a methanol plant.

The process being modeled is a methanol plant. Thebasic feed streams to the plant are Natural Gas, CarbonDioxide (assumed to be taken from a nearby AmmoniaPlant) and Water. The aim is to achieve the methanolproduction rate of approximately 62,000 kg/hr, at a purityof at least 99.95 % wt.

This is a large flowsheet that would take an experiencedengineer more than an afternoon to complete. Startbuilding the flowsheet and think about how you wouldwork to complete the project.



General Guidelines• Build the flowsheet one section at a time.

• Simplify whenever possible. Complexity can always beadded later.

• Investigate the physical properties. Use Analysis. Check if binary parameters are available. Check for two liquid phases. Use an appropriate equation of state for the portions of

the flowsheet involving gases and use an activitycoefficient model for the sections where non-idealliquids may be present.



Full-Scale Plant Modeling Workshop

FURNACEFuel

Air

MEOHRXR

SPLIT1

MIX2

E121COOL4

FL3

SYNCOMP

FL1

FL2COOL1

COOL3COOL2

BOILERE122

CIRC

E124E223

FL4

SPLIT2

FL5

M4

MKWATER

TOPPINGREFINING

M2

SATURATE

FEEDHTR

REFORMER

NATGAS

H2OCIRC

MKUPST

CH4COMP

CO2 CO2COMP M1



Part 1: Front-End Section

M2

SATURATE

FEEDHTR

REFORMER

NATGAS

H2OCIRC

MKUPST

CH4COMP

CO2CO2COMP

From Furnace

To BOILER

M1



Part 1: Front-End Section (Continued)

1. Front-end Section

Carbon Dioxide Stream – CO2• Temperature = 43 C• Pressure = 1.4 bar• Flow = 24823 kg/hr• Mole Fraction

CO2 - 0.9253 H2 - 0.0094 H2O - 0.0606 CH4 - 0.0019 N2 - 0.0028

Natural Gas Stream - NATGAS• Temperature = 26 C• Pressure = 21.7 bar• Flow = 29952 kg/hr• Mole Fraction

CO2 - 0.0059 CH4 - 0.9539 N2 - 0.0008 C2H6 - 0.0391 C3H8 - 0.0003

Circulation Water - H2OCIRC• Pure water stream• Flow = 410000 kg/hr• Temperature = 195 C• Pressure = 26 bar

Makeup Steam - MKUPST• Stream of pure steam• Flow = 40000 kg/hr• Pressure = 26 bar• Vapor Fraction = 1• Adjust the makeup steam flow to achieve a

desired steam to methane molar ratio of 2.8 inthe Reformer feed REFFEED.



Part 1: Front-End Section (Continued)

Carbon Dioxide Compressor - CO2COMP• Discharge Pressure = 27.5 bar• Compressor Type = 2 stage

Natural Gas Compressor - CH4COMP• Discharge Pressure = 27.5 bar• Compressor Type = single stage

Reformer Process Side Feed Stream Pre-Heater - FEEDHTR• Exit Temperature = 560 C• Pressure drop = 0

Saturation Column - SATURATE• 1.5 inch metal pall ring packing.• Estimated HETP = 10 x 1.5 inches = 381 mm• Height of Packing = 15 meters• No condenser and no reboiler.

Reformer Reactor - REFORMER• Consists of two parts: the Furnace portion and the Steam Reforming portion• Exit Temperature of the Steam Reforming portion = 860 C• Pressure = 18 bar



Part 1: Front-End Section Check

Reformer ProductTemperature C 860Pressure bar 18Vapor Frac 1Mole Flow kmol/hr 10266.6541Mass Flow kg/hr 139696.964Volume Flow cum/hr 53937.9538Enthalpy MMkcal/hr -213.933793Mole Flow kmol/hr CO 1381.68394 CO2 751.335833 H2 4882.77068 WATER 2989.25863 METHANOL 0.000686384 METHANE 258.513276 NITROGEN 3.08402321 BUTANOL 0 DME (DIMETHYLETHER) 2.06E-10 ACETONE 2.18E-08 OXYGEN 1.80E-15 ETHANE 0.007007476 PROPANE 6.74097E-07



Part 2: Heat Recovery Section

COOL4

FL3

SYNCOMP

FL1

FL2

COOL1

COOL3COOL2

BOILER

To TOPPINGTo REFINING

To Methanol Loop

From Reformer



Part 2: Heat Recovery Section (Continued)

2. Heat Recovery Section

• This section consists of a series of heat exchangers and flash vessels used to recover the availableenergy and water in the Reformed Gas stream.

BOILER• Exit temperature = 166 C• Exit Pressure= 18 bar

COOL1• Exit temperature = 136 C• Exit Pressure = 18 bar

COOL2• Exit temperature = 104 C• Exit Pressure = 17.9 bar

COOL3• Exit temperature = 85 C• Pressure Drop = 0.1 bar

COOL4• Exit temperature = 40 C• Exit Pressure = 17.6 bar

FL1• Pressure Drop = 0 bar• Heat Duty = 0 MMkcal/hr

FL2• Exit Pressure = 17.7 bar• Heat Duty = 0 MMkcal/hr


SYNCOM• Two Stage Polytropic compressor• Discharge Pressure = 82.5 bar• Intercooler Exit Temperature = 40 C



To Methanol LoopTemperature C 40.0Pressure bar 82.50Vapor Frac 0.997465769Mole Flow kmol/hr 7302.28917

Part 2: Heat Recovery Section Check



Part 3: Methanol Synthesis Section

MEOHRXR

SPLIT1

MIX2

E121

From SYNCOMP

E122

CIRC

E124E223

FL4

SPLIT2

To Furnace

To FL5



Part 3: Methanol Synthesis Section (Continued)

3. Methanol Synthesis Loop Section

Methanol Reactor - MEOHRXR• Tube cooled reactor• Exit Temperature from the tubes = 240 C• No pressure drop across the reactor• Reactions

− CO + H2O <-> CO2 + H2 (Equilibrium)− CO2 + 3H2 <-> CH3OH + H2O (+15 C Temperature Approach)− 2CH3OH <-> DIMETHYLETHER + H2O (Molar extent 0.2kmol/hr)− 4CO + 8H2 <-> N-BUTANOL + 3H2O (Molar extent 0.8kmol/hr)− 3CO + 5H2 <-> ACETONE + 2H2O (Molar extent 0.3kmol/hr)

E121• Exit Temperature - 150 C• Exit Pressure - 81 bar

E122• Cold Side Exit Temperature - 120 C

E223• Exit Temperature - 60 C• Exit Pressure - 77.3 bar

E124• Exit Temperature - 45 C• Exit Pressure - 75.6 bar


CIRC• Single stage compressor• Discharge Pressure = 83 bar• Discharge Temperature = 55 C

SPLIT1• Split Fraction = 0.8 to stream to E121

SPLIT2• Stream PURGE = 9000 kg/hr• Stream RECYCLE = 326800 kg/hr



Part 3: Methanol Synthesis Section Check

To FL5Temperature C 45.0Pressure bar 75.60Vapor Frac 0.000Mole Flow kmol/hr 2673.354

MEOHRXR ProductTemperature C 249.7Pressure bar 83.00Vapor Frac 1.000Mole Flow kmol/hr 29091.739Mass Flow kg/hr 413083.791Volume Flow cum/hr 15637.807Enthalpy MMkcal/hr -559.129Mole Flow kmol/hr CO 799.563 CO2 3137.144 H2 13379.353 WATER 644.301 METHANOL 2140.046 METHANE 8896.430 NITROGEN 91.428 BUTANOL 0.845 DME 1.864 ACETONE 0.588 OXYGEN 0.000 ETHANE 0.177 PROPANE 0.000



Part 4: Distillation Section

FL5

M4

MKWATER

TOPPING

REFINING

From COOL2

To Furnace

From COOL1

From FL4



Part 4: Distillation Section (Continued)

4. Distillation Section

Makeup Steam - MKWATER• Stream of pure water• Flow = 10000 kg/hr• Pressure = 5 bar• Temperature = 40 C• Adjust the make-up water flow (stream MKWATER) to the CRUDE stream to achieve a stream

composition of 23 wt.% of water in the stream feeding the Topping column (stream TOPFEED) toachieve 100 ppm methanol in the Refining column BTMS stream.

Topping Column - TOPPING• Number of Stages = 51 (including condenser and reboiler)• Condenser Type = Partial Vapor/Liquid• Feed stage = 14• Distillate has both liquid and vapor streams• Distillate rate = 1400 kg/hr• Pressure profile: stage 1 = 1.5 bar and stage 51 = 1.8 bar• Distillate vapor fraction = 99 mol%• Stage 2 heat duty = -7 Mmkcal/hr• Stage 51 heat duty Specified by the heat stream• Reboiler heat duty is provided via a heat stream from block COOL2• Boil-up Ratio is approximately 0.52• Valve trays• The column has two condensers. To represent the liquid flow connections a pumparound can be

used between stage 1 and 3.



Part 4: Distillation Section (Continued)

Distillation Section (Continued)

Refining Column - REFINING• Number of Stages = 95 (including condenser and reboiler)• Condenser Type = Total• Distillate Rate = 1 kg/hr• Feed stage = 60• Liquid Product sidedraw from Stage 4 @ 62000 kg/hr (Stream name – PRODUCT)• Liquid Product sidedraw from Stage 83 @ 550 kg/hr (Stream name – FUSELOIL)• Reflux rate = 188765 kg/hr• Pressure profile: stage 1= 1.5bar and stage 95=2bar• Reboiler heat duty is provided via a conventional reboiler supplemented by a heat stream from a

heater block to stage 95• Boil-up Ratio is approximately 4.8• Valve trays• To meet environmental regulations, the bottoms stream must contain no more than 100ppm by

weight of methanol as this stream is to be dumped to a nearby river.

FL5• Exit Pressure 5 bar• Heat Duty 0 MMkcal/hr

M4• For water addition to the crude methanol



Part 4: Distillation Section Check

TOPFEED LTENDS SECPURGE REFINE PRODUCT BTMS LIQPURGE FUSELOILTemperature C 43.8 33.1 33.1 85.8 75.1 120.1 74.8 90.4Pressure bar 5.00 1.50 1.50 1.80 1.52 2.00 1.50 1.95Vapor Frac 0.001 1.000 0.000 0.000 0.000 0.000 0.000 0.000Mole Flow kmol/hr 3029.767 33.807 0.341 2995.618 1928.736 1047.117 0.031 19.733Mass Flow kg/hr 82623.475 1388.896 11.104 81223.475 61800.974 18871.500 1.000 550.000Volume Flow cum/hr 111.175 573.782 0.014 107.201 83.975 21.058 0.001 0.722Enthalpy MMkcal/hr -186.388 -2.802 -0.020 -178.587 -107.391 -69.633 -0.002 -1.199Mole Flow kmol/hr CO 0.004 0.004 0.000 0.000 0.000 0.000 0.000 0.000 CO2 26.537 26.535 0.002 0.000 0.000 0.000 0.000 0.000 H2 0.014 0.014 0.000 0.000 0.000 0.000 0.000 0.000 WATER 1054.851 0.000 0.000 1054.851 0.000 1046.942 0.000 7.910 METHANOL 1945.891 5.591 0.334 1939.966 1928.733 0.059 0.031 11.143 METHANE 1.267 1.267 0.000 0.000 0.000 0.000 0.000 0.000 NITROGEN 0.003 0.003 0.000 0.000 0.000 0.000 0.000 0.000 BUTANOL 0.798 0.000 0.000 0.798 0.000 0.117 0.000 0.681 DME 0.116 0.116 0.000 0.000 0.000 0.000 0.000 0.000 ACETONE 0.285 0.276 0.005 0.004 0.004 0.000 0.000 0.000 OXYGEN 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 ETHANE 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000 PROPANE 0.000 0.000 0.000 0.000 0.000 0.000 0.000 0.000



Part 5: Furnace Section

FURNACE

Fuel

Air

From FL5

From SPLIT2

To REFORMER



Part 5: Furnace Section (Continued)

5. Furnace Section

Air to Furnace - AIR• Temperature = 366 C• Pressure = 1 atm• Flow = 281946 kg/hr• Adjust the air flow to achieve 2%(vol.) of oxygen in the FLUEGAS stream.

Fuel to Furnace - FUEL• Flow = 9436 kg/hr• Conditions and composition are the same as for the natural gas stream


Potential

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Additional Topics


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Maintaining Aspen Plus Simulations

Objective:

Introduce how to store simulations and retrieve themfrom your computer environment

Aspen Plus References: • User Guide, Chapter 15, Managing Your Files



File Formats in Aspen Plus

File Type Extension Format DescriptionDocument *.apw Binary File containing simulation input and results and

intermediate convergence information

Backup *.bkp ASCII Archive file containing simulation input andresults

Template *.apt ASCII Template containing default inputs

Input *.inp Text Simulation input

Run Message *.cpm Text Calculation history shown in the Control Panel

History *.his Text Detailed calculation history and diagnosticmessages

Summary *.sum ASCII Simulation results

ProblemDefinition

*.appdf Binary File containing arrays and intermediateconvergence information used in the simulationcalculations

Report *.rep Text Simulation report



File Type Characteristics

• Binary files Operating system and version specific Not readable, not printable

• ASCII files Transferable between operating systems Upwardly compatible Contain no control characters, “readable” Not intended to be printed

• Text files Transferable between operating systems Upwardly compatible Readable, can be edited Intended to be printed



How to Store a Simulation

Three ways to store simulations:

Document Backup Input(*.apw) (*.bkp) (*.inp)

Simulation definition Yes Yes YesConvergence info Yes No NoResults Yes Yes NoFlowsheet Graphics Yes Yes Yes/NoUser readable No No YesOpen/save speed High Low LowestSpace requirements High Low Lowest



Template Files

Template files are used to set your personal preferences:• Units of measurement• Property sets for stream reports• Composition basis• Stream report format• Global flow basis for input specifications• Setting Free-Water option• Selection for Stream-Class• Property Method• (Required) Component list• Other application-specific defaults



How to Create a Personal Template

• Any flowsheet (complete or incomplete) can be savedas a template file.

• In order to have a personal template appear on thePersonal sheet of the New dialog box, simply put thetemplate file into the AP101\GUI\Templates\Personalfolder.

• The text on the Setup Specifications Description sheetwill appear in the Preview window when the templatefile is selected in the New dialog box.



Maintaining Your Computer

• Aspen Plus 10 runs best on a healthy computer.

• Minimum RAM

• Having more is better -- if near minimum, avoid runningtoo many other programs along with Aspen Plus.

• Active links increase needed RAM.

GUI only GUI andEngine

Win 95 andWin 98

32 MB 64 MB

Windows NT 64 MB 96 MB



Maintaining Your Hard Disk

• Keep plenty of free space on disk used for: Your Aspen working directory Windows swap files

• Delete unneeded files: Old .appdf, .his, etc. Aspen document files (*.apw) that aren’t active Aspen temporary files (_4404ydj.appdf, for example)

• Defragment regularly (once a week), even if Windowssays you don’t need to -- make the free spacecontiguous.


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Customizing the Look of Your Flowsheet

Objective:Introduce several ways of annotating your flowsheet tocreate informative Process Flow Diagrams

Aspen Plus References:• User Guide, Chapter 14, Annotating Process Flowsheets

Related Topics:• User Guide, Chapter 37, Working with Other Windows Programs



Customizing the Process Flow Diagram• Add annotations

Text Graphics Tables

• Add OLE objects Add a titlebox Add plots or diagrams

• Display global data Stream flowrate, pressure and temperature Heat stream duty and work stream power Block duty and power

• Use PFD mode Change flowsheet connectivity



Viewing

• Use the View menu to select the elements that you wishto view: PFD Mode Global Data Annotation OLE Objects

• All of the elements can be turned on and offindependently.



Adding Annotation

• Use the Draw Toolbar to add text and graphics. (SelectToolbar… from the View menu to select the DrawToolbar if it is not visible.)

• To create a stream table, click on the Stream Tablebutton on the Results Summary Streams Materialsheet.

• Annotation objects can be attached to flowsheetelements such as streams or blocks.



Example of a Stream Table

Heat and Material Balance Table

Stream ID COOL-OUT FEED PRODUCT REAC-OUT RECYCLE

Temperature F 130.0 220.0 130.1 854.7 130.1

Pressure PSI 14.60 36.00 14.70 14.70 14.70

Vapor Frac 0.054 1.000 0.000 1.000 1.000

Mole Flow LBMOL/HR 44.342 80.000 41.983 44.342 2.359

Mass Flow LB/HR 4914.202 4807.771 4807.772 4914.202 106.431

Volume Flow CUFT/HR 1110.521 15648.095 93.470 42338.408 1003.782

Enthalpy MMBTU/HR -0.490 1.980 -0.513 2.003 0.023

Mole Flow LBMOL/HR

BENZENE 2.033 40.000 1.983 2.033 0.050

PROPYLEN 4.224 40.000 1.983 4.224 2.241

CUMENE 38.085 38.017 38.085 0.069

Mole Frac

BENZENE 0.046 0.500 0.047 0.046 0.021

PROPYLEN 0.095 0.500 0.047 0.095 0.950

CUMENE 0.859 0.906 0.859 0.029



Adding Global Data

• On the Results View sheet when selecting Options fromthe Tools menu, choose the block and stream resultsthat you want displayed as Global Data.

• Check Global Data on the View menu to display thedata on the flowsheet.

Temperature (F)

Pressure (psi)

Flow Rate (lb/hr)

Q Duty (Btu/hr)

REACTOR

Q=0

220

36

4808

FEED

130

15

106

RECYCLE

855

15

4914

REAC-OUT

COOL

Q=-2492499

130

15

4914

COOL-OUT SEP

Q=0

130

15

4808

PRODUCT



Using PFD Mode

• In this mode, you can add or delete unit operation iconsto the flowsheet for graphical purposes only.

• Using PFD mode means that you can change flowsheetconnectivity to match that of your plant.

• PFD-style drawing is completely separate from thegraphical simulation flowsheet. You must return tosimulation mode if you want to make a change to theactual simulation flowsheet.

• PFD Mode is indicated by the Aqua border around theflowsheet.



Examples of When to Use PFD Mode

• In the simulation flowsheet, it may be necessary to usemore than one unit operation block to model a singlepiece of equipment in a plant. For example, a reactor with a liquid product and a vent may

need to be modeled using an RStoic reactor and a Flash2block. In the report, only one unit operation icon is needed torepresent the unit in the plant.

• On the other hand, some pieces of equipment may notneed to be explicitly modeled in the simulationflowsheet. For example, pumps are frequently not modeled in the

simulation flowsheet; the pressure change can be neglected orincluded in another unit operation block.



Annotation Workshop

Part A:

Using the cyclohexane production Workshop (saved asCYCLOHEX.BKP), display all stream and block global data.

Part B:

Add a title to the flowsheet diagram.

Part C:

Add a stream table to the flowsheet diagram.

Part D:

Using PFD Mode, add a pump for the BZIN stream for graphicalpurposes only.

Objective: Use annotation to create a process flow diagramfor the cyclohexane flowsheet


Potential

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Estimation of Physical Properties

Objectives:

Provide an overview of estimating physical propertyparameters in Aspen Plus

Aspen Plus References:• User Guide, Chapter 30, Estimating Property Parameters• Physical Property Methods and Models Reference Manual,

Chapter 8, Property Parameter Estimation



What is Property Estimation?• Property Estimation is a system to estimate parameters

required by physical property models. It can be used toestimate: Pure component physical property constants Parameters for temperature-dependent models Binary interaction parameters for Wilson, NRTL and

UNIQUAC Group parameters for UNIFAC

• Estimations are based on group-contribution methods andcorresponding-states correlations.

• Experimental data can be incorporated into estimation.



Using Property Estimation• Property Estimation can be used in two ways:

On a stand-alone basis: Property Estimation Run Type Within another Run Type: Flowsheet, Property

Analysis, Data Regression, PROPERTIES PLUS orAssay Data Analysis

• You can use Property Estimation to estimate properties forboth databank and non-databank components.

• Property Estimation information is accessed in theProperties Estimation folder.



Estimation Methods and Requirements• User Guide, Chapter 30, Estimating Property Parameters,

has a complete list of properties that can be estimated, aswell as the available estimation methods and theirrespective requirements.

• This same information is also available under the on-linehelp in the estimation forms.



Steps For Using Property Estimation

1. Define molecular structure on the Properties MolecularStructure form.

2. Enter any experimental data using Parameters or Dataforms. Experimental data such as normal boiling point (TB)

is very important for many estimation methods. Itshould be entered whenever possible.

3. Activate Property Estimation and choose propertyestimation options on the Properties Estimation Inputform.



Defining Molecular Structure

• Molecular structure is required for all group-contributionmethods used in Property Estimation. You can: Define molecular structure in the general format and

allow Aspen Plus to determine functional groups,or Define molecular structure in terms of functional

groups for particular methods

Reference: For a list of available group-contribution method functionalgroups, see Aspen Plus Physical Property Data Reference Manual,Chapter 3, Group Contribution Method Functional Groups.



Steps For Defining General Structure1. Sketch the structure of the molecule on paper.2. Assign a number to each atom, omitting hydrogen.

(The numbers must be consecutive starting with 1.)3. Go to the Properties Molecular Structure Object

Manager, choose the component, and select Edit.4. On the Molecular Structure General sheet, define the

molecule by its connectivity. Describe two atoms at atime:• Specify the types of atoms (C, O, S, …)• Specify the type of bond that connects the two atoms

(single, double, …)

Note: If the molecule is a non-databank component, on theComponents Specifications form, enter a Component ID,but do not enter a Component name or Formula.



Example of Defining Molecular Structure• Example of defining molecular structure for isobutyl

alcohol using the general method Sketch the structure of the molecule, and assign a

number to each atom, omitting hydrogen.

C2

C1

C4

C3

O5



Example of Defining Molecular Structure• Go to the Properties Molecular Structure Object Manager,

choose the component, and select Edit.• On Properties Molecular Structure General sheet,

describe molecule by its connectivity, two atoms at a time.



Atom Types• Current available atom types:

Atom Type Description Atom Type DescriptionC Carbon P PhosphorousO Oxygen Zn ZincN Nitrogen Ga GalliumS Sulfur Ge GermaniumB Boron As ArsenicSi Silicon Cd CadmiumF Fluorine Sn TinCL Chlorine Sb AntimonyBr Bromine Hg MercuryI Iodine Pb LeadAl Aluminum Bi Bismuth



Bond Types• Current available bond types:

Single bond Double bond Triple bond Benzene ring Saturated 5-membered ring Saturated 6-membered ring Saturated 7-membered ring Saturated hydrocarbon chain

Note: You must assign consecutive atom numbers toBenzene ring, Saturated 5-membered ring, Saturated 6-membered ring, Saturated 7-membered ring, andSaturated hydrocarbon chain bonds.




1. Define molecular structure on the Properties Molecular Structure form.

2. Enter any experimental data using Parameters or Dataforms. Experimental data such as normal boiling point (TB) is

very important for many estimation methods. It shouldbe entered whenever possible.

3. Activate Property Estimation and choose property estimation options on the Properties Estimation Inputform.



Example of Entering Additional Data• The following data was obtained for isobutyl alcohol.

Normal boiling point (TB) = 107.6 C Critical temperature (TC) = 274.6 C Critical pressure (PC) = 43 bar

• Enter this data into the simulation to improve theestimated values.



Example of Entering Additional Data• Go to the Properties Parameters Pure Component Object

Manager and create a new Scalar parameter form.• Enter the parameters, the components, and the values.




1. Define molecular structure on the Properties Molecular Structure form.

2. Enter any experimental data using Parameters or Dataforms. Experimental data such as normal boiling point (TB) is

very important for many estimation methods. It shouldbe entered whenever possible.

3. Activate Property Estimation and choose property estimation options on the Properties Estimation Inputform.



Activating Property Estimation• To turn on Property Estimation, go to the Properties

Estimation Input Setup sheet, and select one of thefollowing:

Estimate all missing parametersEstimates all missing required parameters and anyparameters you may request in the optional PureComponent, T-Dependent, Binary, and UNIFAC-Groupsheets

Estimate only the selected parametersEstimates on the parameter types you select on thissheet (and then specify on the appropriate additionalsheets)



Property Estimation Notes• You can save your property data specifications,

structures, and estimates as backup files, and importthem into other simulations (Flowsheet, Data Regression,Property Analysis, or Assay Data Analysis Run-Types.)



Property Estimation WorkshopObjective: Estimate the properties of a dimer,ethycellosolve.

Ethylcellosolve is not in any of the Aspen Plus databanks.

Use a Run Type of Property Estimation, and estimate the properties forthe new component. (Detailed instructions are included on the followingslide.)

The formula for the component is shown below, along with the normalboiling point obtained from literature.

Formula: CH3 - CH2 - O - CH2 - CH2 - O - CH2 - CH2 - OH

TB = 195 C



Property Estimation Workshop (Continued)

• Open a new run, and change the Run Type on the SetupSpecifications Global sheet to Property Estimation.

• Enter a new non-databank component as Component ID DIMER, onthe Components Specifications Selection sheet.

• On the Properties Molecular Structure Object Manager, select DIMERand click Edit.

• On the General sheet, enter the structure.• Go to the Properties Parameters Pure Component Object Manager

and create a scalar parameter form.• Enter the normal boiling point (TB) of DIMER as 195 C.• Run the estimation, and examine the results.• Note that the results of the estimation are automatically written to

parameters forms, for use in other simulations.• Change the Run Type back to Flowsheet on the Setup Specifications

Global sheet.• Go to the Properties Estimation Input Setup sheet, and choose Do

not estimate any parameters.• Now, it is possible to add a flowsheet and use this component.

• Save this file as PCES.BKP.


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Electrolytes

Objective:

Introduce the electrolyte capabilities in Aspen Plus

Aspen Plus References:•User Guide, Chapter 6, Specifying Components•Physical Property Methods and Models Reference Manual,

Chapter 5, Electrolyte Simulation



Electrolytes Examples

• Solutions with acids, bases or salts

• Sour water solutions

• Aqueous amines or hot carbonate for gas sweetening



Characteristics of an Electrolyte System

• Some molecular species dissociate partially orcompletely into ions in a liquid solvent

• Liquid phase reactions are always at chemicalequilibrium

• Presence of ions in the liquid phase requires non-idealsolution thermodynamics

• Possible salt precipitation



Types of Components

• Solvents - Standard molecular species Water Methanol Acetic Acid

• Soluble Gases - Henry’s Law components Nitrogen Oxygen Carbon Dioxide



Types of Components (Continued)

• Ions - Species with a charge H3O+

OH-

Na+

Cl-

Fe(CN)63-

• Salts - Each precipitated salt is a new pure component. NaCl(s) CaCO3(s) CaSO4•2H2O (gypsum) Na2CO3•NaHCO3 •2H2O (trona)



Apparent and True Components

• True component approach Result reported in terms of the ions, salts and

molecular species present after considering solutionchemistry

• Apparent component approach Results reported in terms of base components

present before considering solution chemistry Ions and precipitated salts cannot be apparent

components Specifications must be made in terms of apparent

components and not in terms of ions or solid salts

» Results are equivalent.



Apparent and True Components Example

• NaCl in water

Solution chemistry• NaCl --> Na+ + Cl-• Na+ + Cl- <--> NaCl(s)

Apparent components• H2O, NaCl

True components:• H2O, Na+, Cl-, NaCl(s)



Electrolyte Wizard

• Generates new components (ions and solid salts)

• Revises the Pure component databank search order sothat the first databank searched is now ASPENPCD.

• Generates reactions among components

• Sets the Property method to ELECNRTL

• Creates a Henry’s Component list

• Retrieves parameters for Reaction equilibrium constant values Salt solubility parameters ELECNRTL interaction parameters Henry’s constant correlation parameters



Electrolyte Wizard (Continued)

• Generated chemistry can be modified. Simplifying theChemistry can make the simulation more robust anddecrease execution time.

» Note: It is the user’s responsibility to ensure that theChemistry is representative of the actual chemicalsystem.



Simplifying the Chemistry

• Typical modifications include: Adding to the list of Henry’s components Eliminating irrelevant salt precipitation reactions Eliminating irrelevant species Adding species and/or reactions that are not in the

electrolytes expert system database Eliminating irrelevant equilibrium reactions



Limitations of Electrolytes

• Restrictions using the True component approach: Liquid-liquid equilibrium cannot be calculated.

The following models may not be used:• Equilibrium reactors: RGibbs and REquil

• Kinetic reactors: RPlug, RCSTR, and RBatch• Shortcut distillation: Distl, DSTWU and SCFrac

• Rigorous distillation: MultiFrac and PetroFrac



Limitations of Electrolytes (Continued)

• Restrictions using the Apparent component approach:

Chemistry may not contain any volatile species onthe right side of the reactions.

Chemistry for liquid-liquid equilibrium may notcontain dissociation reactions.

Input specification cannot be in terms of ions or solidsalts.



Electrolyte DemonstrationObjective: Create a flowsheet using electrolytes.

Create a simple flowsheet to mix and flash two feed streams containingaqueous electrolytes. Use the Electrolyte Wizard to generate theChemistry.

FLASH2

FLASHMIXED

VAPOR

LIQUID

MIXER

MIXNAOH

HCL

Temp = 25 CPres = 1 bar10 kmol/hr H2O1 kmol/hr HCl

P-drop = 0Adiabatic

IsobaricMolar vapor fraction = 0.75

Filename: ELEC1.BKP

Temp = 25 CPres = 1 bar10 kmol/hr H2O1.1 kmol/hr NaOH



Steps for Using Electrolytes1. Specify the possible apparent components on the

Components Specifications Selection sheet.

2. Click on the Elec Wizard button to generate componentsand reactions for electrolyte systems. There are 4 steps: Step 1: Define base components and select reaction

generation options. Step 2: Remove any undesired species or reactions from

the generated list. Step 3: Select simulation approach for electrolyte

calculations. Step 4: Review physical properties specifications and

modify the generated Henry components list and reactions.



Electrolyte WorkshopObjective: Create a flowsheet using electrolytes.

Create a simple flowsheet to model the treatment of a sulfuric acidwaste water stream using lime (Calcium Hydroxide). Use the ElectrolyteWizard to generate the Chemistry. Use the true component approach.

B1

WASTEWAT

LIME LIQUID

Temperature = 25CPressure = 1 bar

Flowrate = 10 kmol/hr5 mole% lime (calcium hydroxide) solution

Temperature = 25CPressure = 1 bar

Flowrate = 10 kmol/hr5 mole% sulfuric acid solution

Temperature = 25CP-drop = 0

Note: Remove from the chemistry:CaSO4(s)

CaSO4•1:2W:A(s)

When finished, save asfilename: ELEC.BKP



Sour Water Stripper Workshop

On stage 10P = 15 psiaVapor frac = 12,000 lbs/hr

Above stage 3P = 15 psia10,000 lbs/hr

Mass fractions: H2O 0.997 NH3 0.001 H2S 0.001 CO2 0.001

Saturated vapor

Theoretical trays: 9 (does not include condenser)Partial condenserReflux Ratio (Molar): 25No reboiler

B1

SOURWAT

STEAM

BOTTOMS

VAPOR



Sour Water Stripper Workshop (Continued)

1. Open a new Electrolytes with English units flowsheet.2. After drawing the flowsheet and entering the necessary components, generate the electrolytes using the Electrolytes Wizard. Select the apparent approach and remove all solid salts used in the generated reactions.

Question: Why aren’t the ionic species’ compositions displayed on the results forms? How can they be added?



Sour Water Stripper Workshop (Continued)

3. Add a sensitivity analysis a) Vary the steam flow rate and tabulate the ammonia concentration in the bottoms stream. The target is 50 ppm. b) Vary the column reflux ratio and observe the condenser temperature. The target is 190 F.4. Create design specifications a) After hiding the sensitivity blocks, solve the column with two design specifications. Use the targets and variables from part 3.

Save as: SOURWAT.BKP


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Solids Handling

Objective:

Provide an overview of the solid handling capabilities

Aspen Plus References:• User Guide, Chapter 6, Specifying Components• Physical Property Methods and Models Reference Manual,

Chapter 3, Property Model Descriptions



Classes of Components

• Conventional Components Vapor and liquid components Solid salts in solution chemistry

• Conventional Inert Solids (CI Solids) Solids that are inert to phase equilibrium and salt

precipitation/solubility

• Nonconventional Solids (NC Solids) Heterogeneous substances inert to phase, salt, and

chemical equilibrium that cannot be represented witha molecular structure



Specifying Component Type

• When specifying components on the ComponentsSpecifications Selection sheet, choose the appropriatecomponent type in the Type column. Conventional - Conventional Components Solid - Conventional Inert Solids Nonconventional - Nonconventional Solids



Conventional Components

• Components participate in vapor and liquid equilibriumalong with salt and chemical equilibrium.

• Components have a molecular weight.

ð e.g. water, nitrogen, oxygen, sodium chloride, sodiumions, chloride ions

ð Located in the MIXED substream



Conventional Inert Solids (CI Solids)

• Components are inert to phase equilibrium and saltprecipitation/solubility.

• Chemical equilibrium and reaction with conventionalcomponents is possible.

• Components have a molecular weight.

ð e.g. carbon, sulfur

ð Located in the CISOLID substream



Nonconventional Solids (NC Solids)

• Components are inert to phase, salt or chemicalequilibrium.

• Chemical reaction with conventional and CI Solidcomponents is possible.

• Components are heterogeneous substances and do nothave a molecular weight.

ðe.g. coal, char, ash, wood pulp

ðLocated in the NC Solid substream



Component Attributes

• Component attributes typically represent thecomposition of a component in terms of some set ofidentifiable constituents

• Component attributes can be Assigned by the user Initialized in streams Modified in unit operation models

• Component attributes are carried in the material stream.

• Properties of nonconventional components arecalculated by the physical property system usingcomponent attributes.



Component Attribute DescriptionsAttribute Type Elements DescriptionPROXANAL 1. Moisture

2. Fixed Carbon3. Volatile Matter4. Ash

Proximate analysis, weight %drybasis

ULTANAL 1. Ash2. Carbon3. Hydrogen4. Nitrogen5. Chlorine6. Sulfur7. Oxygen

Ultimate analysis, weight % drybasis

SULFANAL 1. Pyritic2. Sulfate3. Organic

Forms of sulfur analysis, weight %of original coal, dry basis

GENANAL 1. Constituent 12. Constituent 2 :20. Constituent 20

General constituent analysis, weightor volume %



Solid Properties

• For conventional components and conventional solids Enthalpy, entropy, free energy and molar volume are

computed. Property models in the Property Method specified on

the Properties Specification Global sheet are used.

• For nonconventional solids Enthalpy and mass density are computed. Property models are specified on the Properties

Advanced NC-Props form.



Solids Properties - Conventional Solids

For Enthalpy, Free Energy, Entropy and Heat Capacity• Barin Equations

Single parameter set for all properties Multiple parameter sets may be available for

selected temperature ranges List INORGANIC databank before SOLIDS

• Conventional Equations Combines heat of formation and free energies of

formation with heat capacity models Aspen Plus and DIPPR model parameters List SOLIDS databank before INORGANIC



Solids Properties - Conventional Solids

• Solid Heat Capacity Heat capacity polynomial model

Used to calculate enthalpy, entropy and free energy Parameter name: CPSP01

• Solid Molar Volume Volume polynomial model

Used to calculate density Parameter name: VSPOLY

C C C T C TCT

CT

CTp

oS = + + + + +1 2 32 4 5

263

V C C T C T C T C TS = + + + +1 2 32

43

54



Solids Properties - Nonconventional Solids

• Enthalpy General heat capacity polynomial model: ENTHGEN Uses a mass fraction weighted average Based on the GENANAL attribute Parameter name: HCGEN

• Density General density polynomial model: DNSTYGEN Uses a mass fraction weighted average Based on the GENANAL attribute Parameter name: DENGEN



Solids Properties - Special Models for Coal

• Enthalpy Coal enthalpy model: HCOALGEN Based on the ULTANAL, PROXANAL and

SULFANAL attributes

• Density Coal density model: DCOALIGT Based on the ULTANAL and SULFANAL attributes



Built-in Material Stream Classes

Stream Class Description

CONVEN* Conventional components only

MIXNC Conventional and nonconventional solids

MIXCISLD Conventional components and inert solids

MIXNCPSD Conventional components and nonconventionalsolids with particle size distribution

MIXCIPSD Conventional components and inert solids withparticle size distribution

MIXCINC Conventional components and inert solids andnonconventional solids

MIXCINCPSD Conventional components and nonconventionalsolids with particle size distribution

* system default



Unit Operation Models

• General Principles

Material streams of any class are accepted. The same stream class should be used for inlet and

outlet streams (exceptions: Mixer and ClChng). Attributes (components or substream) not recognized

are passed unaltered through the block. Some models allow specifications for each substream

present (examples: Sep, RStoic). In vapor-liquid separation, solids leave with the liquid. Unless otherwise specified, outlet solid substreams

are in thermal equilibrium with the MIXED substream.



Solids Workshop 1Objective: Model a conventional solids dryer.

Dry SiO2 from a water content of 0.5% to 0.1% using air.

Notes: Change the Stream class type to: MIXCISLD.

Put the SiO2 in the CISOLID substream.

The pressure and temperature has to be the same in all thesub-streams of a stream.



Solids Workshop 1 (Continued)

When finished, save asfilename: SOLIDWK1.BKP

Temp = 70 FPres = 14.7 psia

995 lb/hr SiO2 5 lb/hr H2O

FLASH2

DRYERAIR

WET

DRY

AIR-OUT

Pressure Drop = 0Adiabatic

Temp = 190 FPres = 14.7 psiaFlow = 1 lbmol/hr

0.79 mole% N20.21 mole% O2

Design specification:Vary the air flow ratefrom 1 to 10 lbmol/hr toachieve 99.9 wt.% SiO2 [SiO2/(SiO2+Mixed)]

Use the SOLIDS Property Method



Solids Workshop 2Objective: Use the solids unit operations to model theparticulate removal from a feed of gasifier off gases.

The processing of gases containing small quantities of particulatematerials is rendered difficult by the tendency of the particulates tointerfere with most operations (e.g., surface erosion, fouling, plugging oforifices and packing). It is therefore necessary to remove most of theparticulate materials from the gaseous stream. Various options areavailable for this purpose (Cyclone, Bag-filter, Venturi-scrubber, and anElectrostatic precipitator) and their particulate separation efficiency canbe changed by varying their design and operating conditions. The finalchoice of equipment is a balance between the technical performanceand the cost associated with using a particular unit.

In this workshop, various options for removing particulates from thesyngas obtained by coal gasification are compared.




When finished, save asfilename: SOLIDWK2.BKP

DUPL

CYC

FAB-FILT

ESP

V-SCRUBFEED

F-CYC

F-SCRUB

F-ESP

F-BF

S-BF

G-CYC

S-CYC

G-SCRUB

S-SCRUB

LIQ

G-ESP

S-ESP

G-BF

Temp = 650 CPres = 1 barGas Flowrate = 1000 kmol/hr Ash Flowrate = 200 kg/hr

Composition (mole-frac) CO 0.19 CO2 0.20 H2 0.05 H2S 0.02 O2 0.03 CH4 0.01 H2O 0.05 N2 0.35 SO2 0.10

Particle size distribution (PSD)Size limit wt. %[mu] 0- 44 3044- 63 1063-90 2090-130 15130-200 10200-280 15

Temp = 40 CPres = 1 barWater Flowrate = 700 kg/hr

Design ModeMax. Pres. Drop = 0.048 bar

Design ModeHigh EfficiencySeparation Efficiency = 0.9

Design ModeSeparation Efficiency = 0.9Dielectric constant = 1.5

Design ModeSeparation Efficiency = 0.9




• Coal ash is mainly clay and heavy metal oxides andcan be considered a non-conventional component.

• HCOALGEN and DCOALIGT can be used to calculatethe enthalpy and material density of ash using theultimate, proximate, and sulfur analyses (ULTANAL,PROXANAL, SULFANAL). These are specified on theProperties Advanced NC-Props form.

• Component attributes (ULTANAL, PROXANAL,SULFANAL) are specified on the Stream Input form.For ash, zero all non-ash attributes.

• The PSD limits can be changed on the SetupSubstreams PSD form.

• Use the IDEAL Property Method.


Potential

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Optimization

Objective:

Introduce the optimization capability in Aspen Plus

Aspen Plus References:•User Guide, Chapter 22, Optimization

Related Topics:•User Guide, Chapter 17, Convergence•User Guide, Chapter 18, Accessing Flowsheet Variables



Optimization• Used to maximize/minimize an objective function

• Objective function is expressed in terms of flowsheetvariables and In-Line Fortran.

• Optimization can have zero or more constraints.

• Constraints can be equalities or inequalities.

• Optimization is located under /Data/Model AnalysisTools/Optimization

• Constraint specification is under /Data/Model AnalysisTools/Constraint



Optimization Example

For an existing reactor, find the reactor temperature andinlet amount of reactant A that maximizes the profit from thisreactor. The reactor can only handle a maximum coolingload of Q.

Desired Product C $ 1.30 / lbBy-product D $ 0.11 / lbWaste Product E $ - 0.20 /lb

FEED

PRODUCT

REACTORA, B

A + B --> C + D + E

A, B, C, D, E



Optimization Example (Continued)

• What are the measured (sampled) variables? Outlet flowrates of components C, D, E

• What is the objective function to be maximized? 1.30*(lb/hr C) + 0.11*(lb/hr D) - 0.20*(lb/hr E)

• What is the constraint? The calculated duty of the reactor can not exceed Q.

• What are the manipulated (varied) variables? Reactor temperature Inlet amount of reactant A



Steps for Using Optimization1. Identify measured (sampled) variables.

These are the flowsheet variables used to calculatethe objective function (Optimization Define sheet).

2. Specify objective function (expression).

This is the Fortran expression that will be maximizedor minimized (Optimization Objective & Constraintssheet).

3. Specify maximization or minimization of objective function (Optimization Objective & Constraints sheet).



Steps for Using Optimization (Continued)

4. Specify constraints (optional).

These are the constraints used during the optimization(Optimization Objective & Constraints sheet).

5. Specify manipulated (varied) variables. These are the variables that the optimization block will

change to maximize/minimize the objective function(Optimization Vary sheet).

6. Specify bounds for manipulated (varied) variables. These are the lower and upper bounds within which to

vary the manipulated variable (Optimization Varysheet).



Notes

1. The convergence of the optimization can be sensitive tothe initial values of the manipulated variables.

2. It is best if the objective, the constraints, and themanipulated variables are in the range of 1 to 100. Thiscan be accomplished by simply multiplying or dividingthe function.

3. The optimization algorithm only finds local maxima andminima in the objective function. It is theoreticallypossible to obtain a different maximum/minimum in theobjective function, in some cases, by starting at adifferent point in the solution space.



Notes (Continued)

4. Equality constraints within an optimization are similar todesign specifications.

5. If an optimization does not converge, run sensitivitystudies with the same manipulated variables as theoptimization, to ensure that the objective function is notdiscontinuous with respect to any of the manipulatedvariables.

6. Optimization blocks also have convergence blocksassociated with them. Any general techniques used withconvergence blocks can be used if the optimization doesnot converge.



Optimization WorkshopObjective: Optimize steam usage for a process.

The flowsheet shown below is part of a Dichloro-Methane solventrecovery system. The two flashes, TOWER1 and TOWER2, are runadiabatically at 19.7 and 18.7 psia respectively. The stream FEEDcontains 1400 lb/hr of Dichloro-Methane and 98600 lb/hr of water at100oF and 24 psia. Set up the simulation as shown below, and minimizethe total usage of steam in streams STEAM1 and STEAM2, both ofwhich contain saturated steam at 200 psia. The maximum allowableconcentration of Dichloro-Methane in the stream EFFLUENT fromTOWER2 is 150 ppm (mass) to within a tolerance of a tenth of a ppm.Use the NRTL Property Method. Use bounds of 1000 lb/hr to 20,000lb/hr for the flowrate of the two steam streams. Make sure stream flowsare reported in mass flow and mass fraction units before running. Referto the Notes slides for some hints on the previous page if there areproblems converging the optimization.



Optimization Workshop (Continued)

When finished, save as

filename: OPT.BKP

STEAM1

FEED

TOP1

BOT1

TOP2

EFFLUENTSTEAM2

TOWER1

TOWER2


Potential

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RadFrac Convergence

Objective:

Introduce the convergence algorithms and initializationstrategies available in RadFrac

Aspen Plus References:• Unit Operation Models Reference Manual, Chapter 4, Columns



RadFrac Convergence MethodsRadFrac provides a variety of convergence methods forsolving separation problems. Each convergence methodrepresents a convergence algorithm and an initializationmethod. The following convergence methods are available:

• Standard (default)

• Petroleum / Wide-Boiling

• Strongly non-ideal liquid

• Azeotropic

• Cryogenic

• Custom



Method Algorithm Initialization

Standard Standard Standard

Petroleum / Wide-boiling Sum-Rates Standard

Strongly non-ideal liquid Nonideal Standard

Azeotropic Newton Azeotropic

Cryogenic Standard Cryogenic

Custom select any select any

Convergence Methods (Continued)



RadFrac Convergence AlgorithmsRadFrac provides four convergence algorithms:

• Standard (with Absorber=Yes or No)

• Sum-Rates

• Nonideal

• Newton



Standard Algorithm

The Standard (default, Absorber=No) algorithm:

• Uses the original inside-out formulation

• Is effective and fast for most problems

• Solves design specifications in a middle loop

• May have difficulties with extremely wide-boiling orhighly non-ideal mixtures



Standard Algorithm (Continued)

The Standard algorithm with Absorber=Yes:

• Uses a modified formulation similar to the classicalsum-rates algorithm

• Applies to absorbers and strippers only

• Has fast convergence


• May have difficulties with highly non-ideal mixtures



Sum-Rates Algorithm

The Sum-Rates algorithm:

• Uses a modified formulation similar to the classicalsum-rates algorithm

• Solves design specifications simultaneously with thecolumn-describing equations

• Is effective and fast for wide boiling mixtures andproblems with many design specifications

• May have difficulties with highly non-ideal mixtures



Nonideal Algorithm

The Nonideal algorithm:

• Includes a composition dependency in the localphysical property models

• Uses the continuation convergence method


• Is effective for non-ideal problems



Newton Algorithm

The Newton algorithm:

• Is a classic implementation of the Newton method

• Solves all column-describing equations simultaneously

• Uses the dogleg strategy of Powell to stabilizeconvergence

• Can solve design specifications simultaneously or in anouter loop

• Handles non-ideality well, with excellent convergence inthe vicinity of the solution

• Is recommended for azeotropic distillation columns



Vapor-Liquid-Liquid Calculations

You can use the Standard, Newton and Nonidealalgorithms for 3-phase Vapor-Liquid-Liquid systems.On the RadFrac Setup Configuration sheet, selectVapor-Liquid-Liquid in the Valid Phases field.

Vapor-Liquid-Liquid calculations:• Handle column calculations involving two liquid phases

rigorously• Handle decanters• Solve design specifications using:

Either the simultaneous (default) loop or the middleloop approach for the Newton algorithm

The middle loop approach for all other algorithms



Convergence Method Selection

For Vapor-Liquid systems, start with the Standardconvergence method. If the Standard method fails:• Use the Petroleum / Wide Boiling method if the mixture

is very wide-boiling.• Use the Custom method and change Absorber to Yes

on the RadFrac Convergence Algorithm sheet, if thecolumn is an absorber or a stripper.

• Use the Strongly non-ideal liquid method if the mixtureis highly non-ideal.

• Use the Azeotropic method for azeotropic distillationproblems with multiple solutions possible. TheAzeotropic algorithm is also another alternative forhighly non-ideal systems.



Convergence Method Selection (Continued)

For Vapor-Liquid-Liquid systems:

• Start by selecting Vapor-Liquid-Liquid in the ValidPhases field of the RadFrac Setup Configuration sheetand use the Standard convergence method.

• If the Standard method fails, try the Custom methodwith the Nonideal or the Newton algorithm.



RadFrac Initialization Method

Standard is the default Initialization method for RadFrac.This method:

• Performs flash calculations on composite feed to obtainaverage vapor and liquid compositions

• Assumes a constant composition profile

• Estimates temperature profiles based on bubble anddew point temperatures of composite feed



Specialized Initialization Methods

Four specialized Initialization methods are available.

Use: For:

Crude Wide boiling systems with multi-draw columns

Chemical Narrow boiling chemical systems

Azeotropic Azeotropic distillation columns

Cryogenic Cryogenic applications



Estimates

RadFrac does not usually require estimates fortemperature, flow and composition profiles.

RadFrac may require:

• Temperature estimates as a first trial in case ofconvergence problems

• Liquid and/or vapor flow estimates for the separation ofwide boiling mixtures.

• Composition estimates for highly non-ideal, extremelywide-boiling (for example, hydrogen-rich), azeotropicdistillation or vapor-liquid-liquid systems.



Composition Estimates

The following example illustrates the need for compositionestimates in an extremely wide-boiling point system:



RadFrac Convergence Workshop

Objective: Apply the convergence hints explained in thissection.

HCl column in a VCM production plant

• Feed 130000 kg/hr at 50C, 18 bar 19.5%wt HCl, 33.5%wt VCM, 47%wt EDC (VCM : vinyl-chloride, EDC : 1,2-dichloroethane)

• Column 33 theoretical stages partial condenser (vapor distillate) kettle reboiler pressure : top 17.88 bar, bottom 18.24 bar feed on stage 17



RadFrac Convergence Workshop (Continued)

First Step:Specify the column.

Set the distillate flow rate to be equal to the mass flow rate ofHCl in the feed.

Specify that the mass reflux ratio is 0.7. Use Peng-Robinson equation of state (PENG-ROB).

» Question: How should these specifications be implemented?

Note:Look at the results.

Temperature profile Composition profile




Second step:VCM in distillate and HCl in bottom are much too high!

Allow only 5 ppm of HCl in the residue and 10 ppm VCM in thedistillate.

» Question: How should these specifications be implemented?

Note:You may have some convergence difficulties.

Apply the guidelines presented in this section




COL

FEED

DIST

BOT

feed on stage 17

130000 kg/h50 C, 18 bar,HCl 19.5%wtVCM 33.5%wtEDC 47.0%wt mass reflux ratio:0.7

flow : HCl in feed

max 10 ppm VCM

max 5 ppm HCl

17.88 bar

18.24 bar

When finished, save as filename: VCMHCL1.BKP (step 1) and VCMHCL2.BKP (step 2)

Use the PENG-ROB Property method


Potential

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Vinyl Chloride Monomer (VCM) Workshop



VCM Workshop

Vinyl chloride monomer (VCM) is produced through a high pressure,non-catalytic process involving the pyrolysis of 1,2-dichloroethane(EDC) according to the following reaction

CH2Cl-CH2Cl HCl + CHCl=CH2

The cracking of EDC occurs at 500 C and 30 bar in a direct firedfurnace. 1000 kmol/hr of pure EDC feed enters the reactor at 20 C and30 bar. EDC conversion in the reactor is maintained at 55%. The hotgases from the reactor are subcooled by 10 degrees beforefractionation.Two distillation columns are used for the purification of the VCMproduct. In the first column, anhydrous HCl is removed overhead andsent to the oxy chlorination unit. In the second column, VCM product isremoved overhead and the bottoms stream containing unreacted EDCis recycled back to the furnace. Overheads from both columns areremoved as saturated liquids. The HCL column is run at 25 bar and theVCM column is run at 8 bar. Use the RK-SOAVE Property Method.

Objective: Set up a flowsheet of a VCM process using thetools learned in the course.



VCM Workshop (Continued)

1000 kmol/hr EDC20C

30 bar

CRACK

FEED

RECYCIN

REACTOUT

PUMP

RECYCLE

QUENCH

COOLOUT COL1

HCLOUT

VCMIN COL2

VCMOUT

RStoic ModelHeater Model

Pump Model

RadFrac Model

RadFrac Model

30 bar outlet pressure

500 C30 bar

EDC Conv. = 55%

10 deg C subcooling0.5 bar pressure drop

10 stagesReflux ratio = 0.969

Distillate to feed ratio = 0.550Feed enters above stage 7Column pressure = 8 bar

15 stagesReflux ratio = 1.082

Distillate to feed ratio = 0.354Feed enters above stage 8Column pressure = 25 bar

When finished, save asfilename: VCM.BKPUse RK-SOAVE property method

CH2Cl-CH2Cl HCl + CHCl=CH2 EDC HCl VCM



VCM Workshop (Continued)

Part A:

With the help of the process flow diagram on the previous page, set up aflowsheet to simulate the VCM process. What are the values of the followingquantities?

1. Furnace heat duty ________2. Quench cooling duty ________3. Quench outlet temperature ________4. Condenser and Reboiler duties for COL2 ________

________5. Concentration of VCM in the product stream ________

Part B:

The conversion of EDC to VCM in the furnace varies between 50% and 55%.Use the sensitivity analysis capability to generate plots of the furnace heat dutyand quench cooling duty as a function of EDC conversion.


Potential

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ActiveX Automation

Objective:

Introduce ActiveX Automation Capabilities in Aspen Plus

Aspen Plus References:•User Guide, Chapter 38, Using the Aspen Plus ActiveX Automation

Server




• Three Levels Copy/Paste Object Linking and Embedding (OLE) ActiveX Server

• Third level is programming against the software using amacro language. The language demonstrated is VisualBasic for Applications using Excel97 as the interface.



Capabilities of Automation

• Cannot Add Streams Add Unit Operation Blocks Manipulate Flowsheet Graphics

• Can Change Input Specifications Read Output Results Perform Run Control



Aspen Plus Simulation File

• Cannot use Automation to Add Blocks/Streams sostarting point must be an existing Aspen PlusSimulation file

• Can use any of the following file types *.apw Aspen Plus Document *.bkp Aspen Plus Backup File *.inp Aspen Plus Input File *.apt Aspen Plus Template

• For this demonstration, load pfdtut.bkp, Reinitialize,then SaveAs... ActiveXDemo1.bkp



Automation Demonstration 1

• Objective: Create an Excel Workbook that performsthe following Open Aspen Plus Simulation Close Aspen Plus Simulation Run Simulation



Steps to Create Workbook

• Open Excel Setup Excel for VBA Programming Select Reference to Aspen Plus

• Place/Modify Controls

• Add Additional Text to Workbook

• Program General Declarations

• Write Code into Subroutines and Control Events



Setup Excel for VBA Programming

• Open a New Excel Workbook

• Add the “Control Toolbox” Toolbar Select View/Toolbars/Control Toolbox

• Open the VBA programming environment Select Tools/Macro/Visual Basic Environment (VBE)



Select Reference to Aspen Plus

• Make the VBE the active window

• Select Tools/References

• Look for “ASPEN PLUS GUI 10.0-1 Type Library”

• If not found, use Browse button to find ...\APUI\xeq\happ.tlb

• Select reference by clicking the check box and pressing“OK” to complete the task and close the dialogue box



Place/Modify Controls (1 of 6)

• Make the Excel Workbook the active window

• Change the Workbook to Design Mode by pressing the“Design Mode” button on the Control Toolboxtoolbar

• Add 3 Command Buttons to the Workbook Select the Command Button from the Control

Toolbox toolbar Move the cursor on to the Workbook. It will change

to crosshairs. Click the upper left corner of cell G2 Repeat above for cell G4, G6




• Add 1 Check Box to the Workbook Select the Check Box from the Control Toolbox

toolbar Place the control on the upper left corner of cell D2

• The Workbook should look something like this




• Select any of the controls by clicking on it to make thesmall boxes appear around the edge

• With the cursor still over the control, click your RightMouse button (for right-handed people). This will opena pop-up menu.

• Select Properties from this menu. This will display theProperties window




• Change the properties of the controls using the info inthe table below

• Change the control displayed in the property window byselecting the control on the workbook or changing theselection on the top of the property window

Control Property ValueCommandButton1 Name cmd_OpenSimulation

Caption Open SimulationCommandButton2 Name cmd_CloseSimulation

Caption Close SimulationCommandButton3 Name cmd_RunSimulation

Caption Run SimulationCheckBox1 Name chk_IsVisible

Caption Make Visible




• When finished, the Properties window for the CheckBox should look something like this



Add Additional Text to Workbook (1 of 2)

• Use the table to add text to the workbookCell Size/Effect TextA1 16pt/Bold Aspen Plus/ActiveX

DemonstrationA4 12pt/Bold Simulation File



General Declarations


• Select Insert/Module to create a new Basic module

• Insert the following code into the module

• All text in lines that start with a ‘ are comments and donot need to be typed



Code Subroutine


• Add the following code into the Basic Module below theGeneral Declarations written before

• Note: For this and all following code, the code ISCASE-SENSITIVE



Code Control Events (1 of 4)• To code the specific control, make the workbook the

active window, make sure the Design Mode button ispressed, and then Double-Click on the control

• To code the event below, make the workbook the activewindow then double click on the checkbox. The VBEwill open and the cursor will be inside the followingparagraph. The If-Then lines are what needs to betyped



Code Control Events (2 of 4)

• Code the following control event



Code Workbook_BeforeCloseEvent (1 of 2)

• If you exit the workbook without closing the loadedsimulation, the simulation will still exist. It will still be inmemory but not accessible. To prevent this, do thefollowing steps Make the VBE the default Double click on “This Workbook” from the explorer

type view on the left side of the VBE. This willcreate a window in the code area titled “filename -ThisWorkbook (code)

Change the drop down controls to read “Workbook”(left selection) and “Before_Close”



Code Workbook_BeforeCloseEvent (2 of 2)

• Add the following code

• Save the file as ActiveXDemo1.xls



Running Demonstration• Make the Workbook the active window

• Press the Design Mode button so it is inactive

• Press the “Open Simulation” button Find ActiveXDemo1.bkp on your disk

• Press the “Run Simulation” button The program will execute

• The Aspen Plus GUI can be made Visible/Not Visibleusing the check box

• Save the workbook, it is the starting point for theWorkshop



Demonstration of Input/Output

• Objective Modify workbook to accept input and display output

results after running simulation

• The modifications will do the following: Add additional text to workbook Add subroutines in the VBE Modify the code in the Run Command Button




• Use the table to add text to the workbookCell Size/Effect TextA7 12pt/bold Input ValuesD7 12pt/bold Output ValuesA8 10pt/normal Stream 2 Total Flow RateD8 10pt/normal Block B2 Heat DutyB9 10pt/normal lbmol/hrE9 10pt/normal MMBtu/hr



Aspen Plus Variable Explorer (1 of 2)

• Aspen Plus provides a way to find the syntax to specificvariables in a simulation

• Make a copy of the Aspen Plus simulation file and usethe Variable Explorer on the copy

• Found Under Tools/Variable Explorer

• All Numeric Input/Output Variables are found underRoot/Data/[Streams or Blocks]

• When you find the variable of interest, the syntax isdisplayed in the “Path to Node” window. This text canbe copied into your program environment



Aspen Plus Variable Explorer (2 of 2)

• The Variable Explorer will look something like this whenthe proper path to the Block B2 Heat Duty is selected



Code Subroutines

• Add subroutines to Module 1 in the VBE



Modify Run Button Code

• Change the Run Button code to the following

• Save the file as ActiveXDemo2.xls



Running Demonstration• Make the Workbook the active window

• Press the Design Mode button so it is inactive

• Press the Open Simulation Button and loadActiveXDemo1.xls

• Change to cell A9 and enter a value between 100-101

• Press the Run Simulation Button You may have to clear dialogue boxes caused by

the Reinit command

• The simulation will run and the results will be displayedin cell D9



Automation Workshop

• Objective Add code and text to Workbook to perform the

following• Input Temperature of Block B2 (use cell A11, keep

between 350-450 F)• Output Total Flow Rate of Stream 9 (use cell D11)



Workshop Answer (1 of 2)




Workshop Answer (2 of 2)

• Modified Subroutines

• Save the file as ActiveXWorkshop.xls



Additional Topics

• Error Checking is not included in example

• Further capabilities Changing units More Complex Output (RadFrac profiles, stream

reports) More Complex input (changing multiple

specifications, changing composition of streams)

• Covered in “ActiveX Automation of Aspen Plus” course

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