Aspen Plus - Module I

Aspen Plus for Process Design and SimulationDesign and Simulation

Resource PersonsProf Dr Shahid NaveedProf. Dr. Shahid NaveedDr. –Ing. Naveed RamzanAssociate Professor

Mr. Farhan AhmadMr. Farhan AhmadLecturer

Ms Sana Yousaf

Course Organizing OfficerMs. Sana Yusuf

Course Agenda• Role of Simulation in Process Design

• AspenTech Products and Aspen Plus Features

• Aspen Plus graphical User Interface

• Aspen Plus Basics

• Physical Properties Model and Properties Estimation

• HEATX and Heat Exchanger Modelling

• RADFRAC and Distillation Column Modelling

• Unit Operation ModelsUnit Operation Models

• Sensitivity Analysis

• Final Workshop• Final Workshop

Aspen Plus for Process Design and Simulation

Course Agenda (Day – 1)• Role of Simulation in Process Design









• Final Workshop• Final Workshop

Aspen Plus for Process Design and Simulation 3










• Final Workshop

4

• Final Workshop











• Final Workshop

5

• Final Workshop


Role of Simulation in Process DesignProcess Design

Resource Persons

Prof. Dr. Shahid Naveed

6Aspen Plus for Process Design and Simulation

Simulation


Modelling and Simulation

1: What is Modeling

Description of any complete system inmathematical terms is called a mathematicalmodelmodel

2: What is Simulation2: What is Simulation

Solving the modeling equations eithernumerically or analytically


Simulation and Modelling Problem in Process Engineering

Nano Micro Meso Macro Mega

MolecularProcesses,

Bubbles,Drops,Particles

Reactors,Columns,Exchangers,Pumps

ProductionPlants,Petrochemical

Environment,AtmosphereOceans

Active sites Particles,Eddies

Pumps,Compressors,...

PetrochemicalComplexes

OceansSoils

Lit.: Charpentier, J.-C.; Trambouze, P.: Process Engineering and problems encountered by chemical and related Industries in the near future Revolution or cointinuity?

9

by chemical and related Industries in the near future. Revolution or cointinuity? Chemical Enginering and Processing 37(1998) 559-565

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Why Process SimulationThe development of new industrial processes requires the solution ofseveral unknown or expensive problems resulting from the scaling up,such as the impurities behaviour in a continuous run, the optimumsuch as the impurities behaviour in a continuous run, the optimumequipment design, the better fluid distribution, the pressure losses indifferent equipments, the operators training, etc. These problems shall beresolved with the high reliability and less costs as possible before theindustrial plant installation.

To solve these problems it is necessary to run the process either in pilotplants or to construct prototypes, but this way is too expensive andnormally very slow. Computer simulation applications can be used as acomplementary development tool that in many cases lead to accuratesolutions in shorter time and with much less consumption of resourcessolutions in shorter time and with much less consumption of resources.These computational tools are not used aiming to substitute traditionalones, but have demonstrated that can be a helpful complement intechnological development and design engineering

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technological development and design engineering.

Process Simulation Tools

Simulations tools can help to resolve several of theseproblems, with low cost, high reliability and normally in lessproblems, with low cost, high reliability and normally in lesstime. Otherwise these tools can help to the process engineerto understand what happen, and what are the problematicpoints in the whole process or in a particular equipmentpoints in the whole process, or in a particular equipment.These tools can be classified in three groups depending onthe problem that are going to be resolved:

Process Simulation tools.

A computational fluid dynamics (CFD) tools.

Other particular simulation software

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Other particular simulation software.

Process Simulation Tools

Objectives of Process Simulation Tools:

Optimizing the design and performance of product assets Opt g t e des g a d pe o a ce o p oduct assets

Increasing throughput and yield improving quality andIncreasing throughput and yield, improving quality, and reducing energy costs

Responding more quickly to unexpected events or changes in customer demandg

Managing the profitability of operations in real time

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Managing the profitability of operations in real-time.

Types of Process Simulation Tools

In process engineering two types of simulations tools areused:used:

Steady-State Simulators: Or Static simulators.Typically used in process design, they simulate theyp y p g , yprocess at steady state conditions, usually at the designoperating conditions. In this kind of tools Time is not avariablevariable.

Dynamic models: consider time as a variable andsimulate the process over a period of time A dynamicsimulate the process over a period of time. A dynamicsimulation can be used to estimate or illustrate theresponse, over time, to a change in the process.

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Steady State Process Simulation Tools

The steady state simulation tool produce a static simulation, which typically used in process design, to simulate the yp y p g ,process at steady state conditions, usually at the design operating conditions. This simulator don’t use Time as variablevariable.

Th i l ti t l ll th i t d il dThese simulation tools allow the engineer to do easily andstrictly mass balance and energy balance for a high variety ofchemical and petrochemical processes. Equipment andp p q pinstrument design, plant design, capital costs, and technicalevaluations are all dependent on such calculations.

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Steady State Process Simulation ToolsAll of this tools contains:

• A Physical and chemical properties Data Base for severalelements and compounds and different methods to calculate theelements and compounds, and different methods to calculate theproperties of mix.

• A Drawing tool, which can help to produce the Process FlowDi (PFD)Diagrams (PFD).

• A Pre-modelled unit operation; like abortion columns, heaters,reactors, etc.

There are several different software for the steady state processsimulation as:

- VMG Sim - Aspen plus

- Metsim - Chemcad

Others

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- Others

Dynamic Process Simulation Tools

Dynamic simulation tools consider time as a variable andsimulate the process over a period of time. A dynamicsimulation can be used to estimate or illustrate the response,over time, to a change in the process.

This technology is commonly used for design and revampstudies, operator training, testing of DCS configurations andthe development of operating proceduresthe development of operating procedures.

Several of the steady state software tools have an especialmodule to produce the dynamic simulation of the process. Forexample Aspen Dynamics

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Computational Fluid Dynamic (CFD) Tools

Computational Fluid Dynamic (CFD) simulation software hasbeen used for more than twenty years in the aerospace andautomobile industries but it is recently being applied to newautomobile industries, but it is recently being applied to newindustry fields where heat transfer and fluids distributionproblems are present.

CFD is based on finite elements calculations. The simulationsoftware divides the 3D surface in discrete cells creating amesh. The software creates and calculates the Navier–Stokes equations for every cell within the mesh starting fromdefined boundary conditions It is possible to definedefined boundary conditions. It is possible to definecalculation objectives, for instance pressure, temperature,and flow velocity, at selected sites of the simulated volume.

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Computational Fluid Dynamic (CFD) Tools

The following analyses can be performed:•2D and 3D analysis of Newtonian fluids•2D and 3D analysis of Newtonian fluids•External and internal flows •Steady-state and transient-state flows C ibl d ibl fl•Compressible and non-compressible flows

•Laminar, turbulent and transitional flow regimes •Flows with vortex

There are several different CFD software as:

- Fluent

•Multicomponent flows•Heat transference effects•Gravitational effects - Fluent

- Floworks- Flow Science

•Gravitational effects.

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Required Competency

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Impact on Chemical Process Industry

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Design and Analysis through process simulation

Main steps of process simulation

Steady state simulation- Solve algebraic equations

Problem definition

What information do we need?

Problem definition

What do we need to define?

AspenTech Products & Aspen Plus Graphical User InterfaceGraphical User Interface

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Lesson Objectives

Aspen Tech Company Information

Simulation Targets

Li t f A T h P d tList of AspenTech Products

AspenTech Company Information

• Advanced System for Process Engineering (ASPEN)

• Project conducted at the Massachusetts Institute of Technology (MIT) in Cambridge MassachusettsTechnology (MIT) in Cambridge Massachusetts, from 1976 to 1981

• Over 2000 Employees world wide• HQ in Cambridge, MA (Boston)• Offices in 35 Countries• Public held since 1994, NASDAQ• www.aspentech.com

http://support aspentech com• http://support.aspentech.com

Process Simulation TargetsProcess Simulation

Debottlenecking

R i

Optimization,design etc.

H t i t ti tSteady State Simulation Revamping

Operation

Heat integration etc.

Sensitivity, maintenance

Steady State Simulation

Process Control Real time optimization

Operation

Dynamic Simulation

Start up, Shut down, safety

Operator Training

Operational failures Safety examinations, designDisturbance Simulation

Operator Training

Products • Process Engineering

» Process simulation Chemicals (10 products : AspenPlus)» Process simulation Oil&Gas (8 products : AspenHYSYS)( p p )» Process simulation Refining (11 products : Aspenadsim+)» Process simulation Batch/Pharma (8 products :Aspenproperties)» Model Deployment (3 products : AspenModelrunner)» Equipment modeling (8 products :AspenAcol+)» Basic Engineering (2 products :AspenKbase)» Economic Evaluation (3 products : Aspn Icarus Project Manager)

• Advance Process Control (14 products : Aspen Apollo, Aspen IQ)

• Planning & Scheduling (10 products : Aspen Advisor Aspen MBO)• Planning & Scheduling (10 products : Aspen Advisor, Aspen MBO)

• Supply & Distribution (3 products : Aspen Retail)

• Production Management & Execution (16 products : Aspen 0server)

Products• Aspen Plus

Aspen Plus is the most popular product (accounted 48% of sales in 1995)of sales in 1995)a steady state modeling system built around the core technology

• Properties PLUSIt is a database of chemicals properties underlying its other products popular with customers ~ developed inother products, popular with customers ~ developed in-house modeling software

Oth d l• Other modules» offers to the customers ~ license separately » use with its other products to model subsystems used

i hi hl i li d h i l i li iin highly specialized chemicals processing application.

Flowsheet Simulation

Flowsheet Simulation

General Simulation Problem

Approaches to Flowsheet Simulation

Good Flowsheeting Practice

Why Aspen Plus?

Starting with Aspen Plus

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The User Interface

FlowSheet Definition


Automatic Naming of Streams and Blocks

Graphic Flowsheet Operations--Blocks

Graphic Flowsheet Operations-- Streams

Using the Mouse Button

Modifying Blocks and Streams

Exercise-I

48


Basic Input to Run Aspen Plus SimulationSimulation

50

Aspen Plus User Interface

Data Browser

Data Browser

Functionality of Forms

Help

Basic Input

Status Indicators

Example

Setup

Setup Specification Form

Setup Run Types

Setup Units

Components

Component Specification Form

Entering Components

Find

Pure Component DataBanks

Pure Component DataBanks

Properties

Properties Specification Form

Streams

Streams Input Form

Blocks

Blocks

Starting the Run

Control Panel

Reviewing Results

Exercise-II

July 06, 2010 78

Exercise-II

Property Packages & &

Property Estimation

Resource Person

FARHAN AHMAD

Contents

• Introduction

• Properties of Unit Operations

• Property Packages

» Ideal model

» Equation-of-state model

A i i d l» Activity model

» Special models

• Selection of Property Package• Selection of Property Package

• Recommended Property Packages

Simulation Algorithm

Types of properties

Th th t f tiThere are three types of properties:

» Thermodynamic properties» Transport properties» Kinetic properties

Why are physical properties important ?

• A key requirement of process design is the need to• A key requirement of process design is the need toaccurately reproduce the various physical properties thatdescribes chemical species.

• Accurate representation of physical properties is essentialkey to meaningful simulation result.

• Aspen Plus also allow you to predict properties of mixturesranging from well defined light hydrocarbon systems toomple oil mi t es and highl non ideal (non ele t ol te)complex oil mixtures and highly non-ideal (non-electrolyte)

chemical systems.

Properties of Unit Operations

Can we believe simulation results?

Reasons:Reasons:

• Improperly selected thermodynamic models.

• Inadequate model parameters.

• Incorrect hypothetical components generation• Incorrect hypothetical components generation.

• Problems with plant data consistency.

Property Package

• Property package is a collection of models that simulationtool (Aspen Plus) uses to compute thermodynamictool (Aspen Plus) uses to compute thermodynamic,transport and other properties.

P t k d fi d b l l ti th ( t )• Property packages are defined by calculation paths (routes)and physical property equations (models), which determinehow properties are calculated.

• Aspen Plus includes a large number of built-in propertypackages that are sufficient for most applications.

» Modification of existing package» Develop a new package

Available Property Packages

• Property methods ca be categorized into 4 groups:• Property methods ca be categorized into 4 groups:

» Ideal» Equation-of-state» Activity coefficient» Special

Ideal Property Method

Ideal Property method uses the following calculation methodsand models:

• Most basic property methods

and models:

• Most basic property methodsbased on ideal behavior ofsystem.

• Mixture properties are basedon mole fraction averages ofpure components propertiespure components properties.

Equation-of-state Property Packages

EOS property method uses the following calculation methodsand models:

• It accounts the Departure fromideality.

• In EOS property methods,vapor and liquid properties areall calculated by the same

d lmodel.

• Extrapolates reasonably wellwith temperature and pressure.

• Inability to accurately predictab ty to accu ate y p ed cthighly non-ideal liquidmixtures.

Activity coefficient Property Methods

Activity coefficient property methods use the followingcalculation methods and models for pure component

• Vapor and liquid propertiesl l d b diff

properties:

are calculated by differentmodels.

• Ability to represent highlynon-ideal liquid mixtures.

• Inconsistent in the criticalregion.

Activity coefficient Property packages

Special Property packages

• Additional property packages use special correlations and are available for special applications:are available for special applications:

Selection of

Property Packagesp y g

How to choose the best property prediction

method for simulation ?

Importance of Selecting the Appropriate

property package p p y p g

• Correct predictions of the physical properties of the mixtureCorrect predictions of the physical properties of the mixtureas a function of temperature and pressure.

• Each method is suitable only for particular types of• Each method is suitable only for particular types ofcomponents and limited to certain operating conditions.

Choosing the wrong method may lead to incorrect• Choosing the wrong method may lead to incorrectsimulation results.

l l f l bl d• Particularly important for reliable computations associatedwith separation operations (distillation, LL extraction, etc.).

Example: 2-propanol water

Principle Steps in Selecting the Appropriate

Property Packagep y g

1. Choosing the most suitable model.g

2. Comparing the obtained predictions with data from theliterature.

3. Adding estimates for components that not available in thechosen package.

4. Generation of lab data if necessary to check the propertymodel.

Criteria of choosing suitable property package

• The choice of which the property package to use should be based on based on

» Composition» Temperature and pressure» Temperature and pressure» Availability of parameters

Issues in Selection of the Appropriate property Packagep p y g

• Nature of mixture(e.g., hydrocarbon, polar, electrolyte, etc.)

• Pressure and temperature range

• Availability of data

Sources of Information

• Publications and professional literature that deal with theprocess in question or with the components in the process.

• Simulator reference manual (HELP).

• Databanks

• Rules of thumb.Rules of thumb.

Property Package Decision Flowchart

Guidelines for choosing a property package



Recommendations for the Selection of the Appropriate Property Package

• Eric Carlson, “Don’t gamble with physical properties forsimulations,” Chem. Eng. Prog. October 1996, 35-46

• Prof J.D. (Bob) Seader, University of Utah

• Hyprotech Recommendations• Hyprotech Recommendations

Recommended Property Packages





Hyprotech Recommendations

Example

• Find the best thermodynamic package for 1-Propanol• Find the best thermodynamic package for 1-Propanol ,H2O mixture.

1-Propanol ,H2O mixture

Non-electrolyteSee Figure 2

Figure 1

E?Polar

Polarity

R?Real or pseudocomponents

P? Pressure

E? Electrolytes

LL?Yes

ij?

LL?

P < 10 bar NoWILSON, NRTL,UNIQUAC and their variances

Figure 2

P?

j

No

their variances

P?

UNIFAC and its

PolarNon-electrolytes

LL?No

Noextensions

LL? Liquid/Liquid

P? Pressure

ij?ij? Interaction ParametersAvailable

HC? Hydrocarbons

LG? Light gasesFigure 3

LG?Yes

PC? Organic Polar Compound

Yes See Figure 4

HC?No PC?

Compound

Figure 4 Yes NRTL, UNIQUAC

PPS?Available

BIP?PC with HC

Binary InteractionUNIFACNot Available

PPS? Possible PhaseSplitting

BIP? Binary InteractionParameters

Splitting

1-Propanol, H2O

98

100TXY diagram for 1-Propanol, H2O

Perry NRTL

94

96

98 NRTL PRSV UNIQUAC Van-Laar (Built-inVan-Laar(Perry)

90

92

94

T [o C

]

86

88

90T

0 0 1 0 2 0 3 0 4 0 0 6 0 0 8 0 9 182

84

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

1-Propanol mol. frac.

RADFRAC & Distillation Column ModelingModeling

Resource PersonDr. –Ing. Naveed Ramzan

Associate Professor

118

Lesson Objectives

Multi-Stage Separation Models in Aspen Plus

RADFRAC

RADFRAC Flowsheet Connectivity

RADFRAC Configuration Options

RADFRAC Modeling Approach

Mathematical Model Behind RADFRAC

QcV2Stage f-1

D

Q

L

2

Stage 2 vik

V H

Stage k-1

lik-1

L h

vif

VfHf

lif-1Lif-1hf- 1

Vif+VifViF

DL1

Stage f

F

S Stage p

vik+1

Vk=1HK+

VkHK

likLk hK

Stage kLk-1 hK-1

vif+1 lif

lif-1+liF

liF

Stage f

BStageN

S Stage p

Overall Column Model

1

Simple Stage Model

Vf+1Hf+1 Ljhf

Feed Stage Model+l l 0 l L F l 0Overall Column Model

Fi+Si-Di-Bi=0F+S-D-B=0

vik+1+lik-1-vik-lik=0

Vk+1+Lk-1-Vk-Lk=0

vif+1+lif-1+LiF-vif-lif=0

Vf+1+Lf-1+Ff –Vf – Lf =0


The Equilibrium Equation The Summation Equation

yik = Kik xik OR vik/ Vk = Kik lik/ Lk

Kik = Kik( Tk,Pk, xik yik )

For Liquid Phase∑c

i xik –1 = 0 or ∑c l / L 1 = 0

For Vapor Phase∑c

i yik –1 = 0 or ∑c v / V 1 = 0ik = ik( k, k, ik , yik ) or ∑c

i lik/ Lk –1 = 0 or ∑c

i yik/ Kik –1 = 0 or ∑c

i vik/ Vk –1 = 0 or ∑c

i Xik Kik –1 = 0


Overall Energy Balance for Column

FHF-DHD-BhB +SHS-QC=0

For Condenser

V2H2+L1h1-DH1-Qc = 0For Simple Stage

Vk+1Hk+1+Lk-1hk-1-Lkhk-VkHk=0

2 2 1 1 1 Qc

Hk = Hk( Tk,Pk , yik )

For Feed Stage

FH +V H +L h -L h -V H =0

hk = hk( Tk,Pk , xik )

FHF+Vf+1Hf+1+Lf-1hf-1-Lfhf-VfHf=0

Some RADFRAC Options

RADFRAC Demonstration

Basic Column Specifications

Basic Column Specifications

Optional Column Specifications

Operating Specification Selection Tips

Operating Specification Selection Tips

RADFRAC Setup Configuration sheet



RADFRAC Setup Streams sheet



RADFRAC Setup Pressure sheet

Plot wizard

Plot wizard

Plot wizard

Exercise

July 06, 2010 145

Exercise

Exercise

Column Performance Specifications

RADFRAC Design Specifications






Example: Design Specifications

Example: Design Specifications

Exercise

July 06, 2010 157

Exercise

Exercise

Aspen Plus for Process Design and SimulationDesign and Simulation

Course Agenda

• Role of Simulation in Process Design

• Aspen Tech Products and Aspen Plus BasicsAspen Tech Products and Aspen Plus Basics


• HEATX and Heat Exchanger Modelling• HEATX and Heat Exchanger Modelling


Unit Operation Models• Unit Operation Models


i l k h• Final Workshop

July 06, 2010 Aspen Plus for Process Design and Simulation 161

Course Agenda (Day –3)

• Role of Simulation in Process Design

• Aspen Tech Products and Aspen Plus BasicsAspen Tech Products and Aspen Plus Basics


• HEATX and Heat Exchanger Modelling• HEATX and Heat Exchanger Modelling


Unit Operation Models• Unit Operation Models


i l k h• Final Workshop

July 06, 2010 162Aspen Plus for Process Design and Simulation

Sensitivity Analysis using Aspen PlusAspen PlusResource Person

Dr. Naveed Ramzan

July 06, 2010 163Aspen Plus for Process Design and Simulation

Cumene Production Process

Lesson Objectives

Sensitivity Analysis

Defining the Sensitivity Analysis



Uses of Sensitivity Analysis

Sensitivity Analysis Example

Sensitivity Analysis Example

Assessing Variables

Variable Definition

Variable Definition Example

Variable Definition Notes

Steps for Sensitivity Analysis


P itPurity (mole fraction) of cumene in Product StreamStream


P itPurity (mole fraction) of cumene in Product StreamStream


COOLCOOL Outlet Temperature


COOLCOOL Outlet Temperature



Viewing Results

Plotting

Notes

Exercise

July 06, 2010 187

Exercise

Thermodynamic Model

What would be the effect of flow rate of phenol onWhat would be the effect of flow rate of phenol on MCH distillate purity, Condenser duty, reboiler duty


Final Workshop

Resource PersonsProf. Dr. Shahid NaveedDr. –Ing. Naveed RamzanMr. Farhan Ahmad Ms Sana Yosuf

Process Description

Flow Sheet Diagram

Sensitivity Analysis

Design Specification

Aspen Plus - Module I

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