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Visual Cue Narration
Slide Number 1

Title Slide

Welcome to this tutorial on Simulating a PFR using Heterogeneous Catalytic Reaction in DWSIM.
Slide Number 2

Learning Objective

In this tutorial, we will learn to:
  • Define a Heterogeneous Catalytic reaction
  • Define parameters for PFR required to simulate a Heterogeneous Catalytic Reaction
  • Calculate Conversion and Residence time for Heterogeneous Catalytic Reaction in a PFR
Slide Number 3

System Requirements

To record this tutorial, I am using
  • DWSIM 5.7 Update 8 and
  • Windows 10

The process demonstrated in this tutorial is identical in other OS also such as-* Ubuntu Linux,

  • Mac OS X or
Slide Number 4


To practice this tutorial, you should know to-
  • add components to a flowsheet
  • select thermodynamic packages
  • add material and energy streams and specify their properties.
Slide Number 5

Prerequisite Tutorials and Files


The prerequisite tutorials are available on this website.

You can access these tutorials and all the associated files from this site.

Slide Number 6

Problem Statement

Reaction: CH4 + H2O ⇔ 3H2 + CO

Inlet Stream:

Mass Flow: 300 kg/h

Mole Fraction(CH4): 0.4975

Mole Fraction(H2O): 0.4975

Mole Fraction(H2): 0.005

Temperature: 730 degree C

Pressure: 1.01325 bar

Property Package: Peng Robinson(PR)

PFR Dimensions:

Volume: 1 m3, length: 1 m

We will develop a flowsheet to determine the exit composition from an Isothermal PFR with Heterogeneous Catalytic Reaction.

Here we give Inlet stream conditions, Property package and Reactor Parameters.

Slide Number 7

Catalyst Properties:

Loading: 0.386 kg/m3

Particle Diameter: 0.002 m

Void Fraction: 0.4

Gas Constant: R = 8.314 J/mol-K

Next, we give the Catalyst properties and Gas constant.
Slide Number 8

Reaction Rate and Coefficients:

R1 = [k1/PH22.5 {PCH4 PH2O - PH23 PCO / K1}] / DEN2

Reaction Rate

k1 = 4.22 * 10 15 exp (- 240100/RT)

K1 = exp (30.42 - 27106/T)

DEN = 1 + KCH4 PCH4 + KCO PCO + KH2 PH2 + KH2O PH2O/PH2

Now we give the reaction rate and its coefficients.
Slide Number 9

Reaction Rate Coefficients

k1 = 6.65 * 10-4 exp (38280/RT)

k1 = 1.77 * 105 exp (- 88680/RT)

k1 = 6.12 * 10-9 exp (82920/RT)

k1 = 8.23 * 10-5 exp (70650/RT)

Here we give the reaction rate coefficients.
Before we start the simulation, we will simplify the rate expression.
We will substitute the coefficients in the rate for the numerator and denominator separately.

This will be helpful when we have to enter the reaction rate for Heterogeneous Catalytic reaction.

In the rate expression, we will assign the variables for partial pressure of reactants and products.
Slide Number 10

Reactants: R

PCH4: R1, PH2O: R2

Products: P

PH2: P1, PCO: P2

R corresponds to reactants.

Partial pressure of Methane(CH4) is R1 and Water(H2O) is R2.

P corresponds to products.

So partial pressure of Hydrogen(H2) is P1 and Carbon monoxide(CO) is P2.

Slide Number 11

Numerator of R1 = k1/PH22.5 {PCH4 PH2O - PH23 PCO / K1}

Substituting for k1, PH2, PCH4, PH3, PCO and K1, we get


The numerator term in the rate expression is this.

Substituting the values of k1, K1 and partial pressure terms, the numerator becomes like this.

Slide Number 12

Denominator of R1 = [1 + KCH4 PCH4 + KCO PCO + KH2 PH2 + KH2O PH2O/PH2] 2

Substituting for KCH4, PCH4, KCO, PCO, KH2, PH2, KH2O and PH2O, we get


The denominator term in the rate expression is this.

Substituting the values of KCH4, KCO, KH2, KH2O and partial pressure terms, the denominator becomes like this.

We have simplified the rate expression to be entered in DWSIM.

Now we will start the simulation.

File >> New Steady-state Simulation I have already opened DWSIM.

Go to File menu and select New Steady-state Simulation.

Point to Simulation Configuration Wizard window Simulation Configuration Wizard window appears.
Click on Next button. Click on Next button.
First, we will add the compounds.
Type Methane in the Search tab

ChemSep database >> Methane

Check the checkbox under column Added

In the Compounds Search tab, type Methane.

Select Methane from ChemSep database.

Check the checkbox under column Added.

Type Water in the Search tab Next, add Water from ChemSep database.
Type Hydrogen in the Search tab Then, add Hydrogen from ChemSep database.
Type Carbon monoxide in the Search tab Next, add Carbon monoxide from ChemSep database.
Type Carbon dioxide in the Search tab Next, add Carbon dioxide from ChemSep database.

Now, all the compounds are added.

Click on Next. Click on Next button.
Point to Property Packages Next is Property Packages.
Property Packages >> Available Property Package

Double click on Peng-Robinson (PR)

From Available Property Package list, double click on Peng-Robinson (PR) option.
Click on Next. Then click on the Next button.
Point to System of Units Next option is System of Units.
System of Units >> C5 Under System of Units, we will select C5.
Click on Finish Then at the bottom, click on the Finish button.
Click on Maximize button Let us maximize the simulation window.
Cursor on the simulation window. Now insert a feed stream that enters the Reactor.
Point to Streams. At the bottom of the main simulation window, go to Streams.
Click and drag Material Stream to the flowsheet From the displayed list, drag and drop Material Stream to the Flowsheet.
Click MSTR-000 Click on the material stream named MSTR-000.
Type Feed Let’s change the name of this stream to Feed.
Now we will specify the Feed stream properties.
Stream Conditions >> Flash Spec >> Temperature and Pressure (TP) Go to Input Data.

Under Stream Conditions tab, select Flash Spec as Temperature and Pressure (TP), if not already selected.

Point to the default temperature and pressure. By default, Temperature and Pressure are already selected as Flash Spec.
Stream Conditions >>Temperature >> 730 C

Press Enter

Change Temperature to 730 degree C and press Enter.
Stream Conditions >> Pressure >> 1.01325 bar

Press Enter

Change Pressure to 1.01325 bar and press Enter.
Stream Conditions >> Mass Flow >> 300 kg/h

Press Enter

Change Mass Flow to 300 kg/h and press Enter.
Input Data >> Compound Amounts Now let us specify the Feed stream compositions.

For this click on Compound Amounts tab under Input Data.

Basis >> Mole Fractions Choose the Basis as Mole Fractions, if not already selected.

By default, Mole Fractions is already selected as the Basis.

Methane: 0.4975 Now for Methane, enter the Amount as 0.4975 and press Enter.
Water: 0.4975 For Water, enter 0.4975 and press Enter.
Hydrogen: 0.005 For Hydrogen, enter 0.005 and press Enter.
Carbon monoxide: 0 For Carbon monoxide, enter 0 and press Enter.
Carbon dioxide: 0 For Carbon dioxide, enter 0 and press Enter.
Click Accept Changes button On the right, click on the Accept Changes button.
Now we will define the Heterogeneous Catalytic Reaction.
Edit>> Simulation Settings

Click Reactions

Under Edit, Click on Simulation Settings.

Click on the tab Reactions.

Chemical Reactions >> Add Reaction Under Chemical Reactions tab, click on the green coloured Add Reaction button.
Click on Heterogeneous Catalytic Click on Heterogeneous Catalytic.
Point to Heterogeneous Catalytic Reaction Heterogeneous Catalytic Reaction window opens.
Identification >> Name >> Steam Reforming Under Identification, enter the Name as Steam Reforming.
Description >> Catalytic Reaction for Steam Reforming Next, enter the Description as,

Catalytic Reaction for Steam Reforming

Point to Components and Stoichiometry Next part is a table of Components and Stoichiometry.
Point to Name field First column Name, shows the available components here.
Point to Molar Weight Second column corresponds to its Molar Weight.
Point to Heat of Formation Third column corresponds to its Heat of Formation.
Point to Include Next column is Include.

Under Include, check the check boxes against Methane, Water, Hydrogen and Carbon monoxide.

Carbon dioxide doesn’t take part in this reaction.

We will keep it unchecked.

Point to BC

Check Methane check box

Fourth column is BC.

Under BC, check the Methane check box as Methane is the base component.

Point to Stoich. Coeff Next column is Stoich. Coeff. (stoichiometric coefficients)

Stoich. Coeff >> Methane: -1,

Water: -1

Hydrogen: 3,

Carbon monoxide: 1,

Carbon dioxide: 0'

Under Stoic Coeff column, enter

-1 for Methane

-1 for Water

3 for Hydrogen

1 for Carbon monoxide

0 for Carbon dioxide

Then press Enter.

Point to Stoichiometry field In the Stoichiometry field, we can see it is showing OK.
Point to Equation field Here the Equation field shows the reaction equation.
Point to Heterogeneous Kinetic Reaction Parameters Next part is Heterogeneous Kinetic Reaction Parameters.
Basis >> Partial Pressures Select Basis as Partial Pressures.
Phase >> Vapor Select Phase as Vapor.
Leave Tmin and Tmax unchanged. We will leave Tmin and Tmax field as unchanged.
Now we will specify the reaction rate.
Point to Reaction Rate(Base Component) Go to Reaction Rate (Base Component) = Numerator/Denominator.
Point to Numerator and Denominator field. The reaction rate is to be entered separately as Numerator and Denominator.

We have already simplified the Numerator and Denominator part separately.

Point to Numerator



We will enter the Numerator part first.

Type the equation as shown here.

Point to Denominator



Now we will enter the Denominator part.

Type the equation as shown here.

Now we will specify the units for Amount and Velocity.
Amount Unit >> atm Select Amount Unit as atm from the dropdown.

The Reaction Rate is expressed in terms of Partial Pressure, whose unit is atm.

Velocity Unit >> kmol/[kg.h] From the drop-down select Velocity Unit as kmol/[kg.h].

This is the unit for the Reaction Rate.

Click OK Click on OK button.
Click on Flowsheet Now go back to Flowsheet area.
We will use a Plug Flow Reactor for the simulation.
Cursor to Reactors tab At the bottom of the main simulation window, go to Reactors tab.
Click and drag Plug-Flow Reactor(PFR) to the flowsheet Drag and drop Plug-Flow Reactor(PFR) to the flowsheet area.
Let us arrange it as required.
And then let us insert one Output Stream.
Click and drag Material Stream to the flowsheet To do that let us drag one Material Stream.
Let us once again arrange it in the flowsheet.
Leave that stream as unspecified.
Type Product We will change the name of this stream to Product.
Click and drag Energy Stream to the flowsheet Let us now insert one Energy Stream.
Type Energy. Name this stream as Energy.
Click Plug-Flow Reactor (PFR) We are now ready to specify the Plug-Flow Reactor.

So let’s click on it.

Point to the tab on the left. On the left, we can see a tab displaying properties related to the PFR.
Go to aConnections

Click on drop down arrow against Inlet Stream

Select Feed.

Under Connections, click on the drop down against Inlet Stream.

Select Feed.

Click on drop down arrow against Outlet Stream

Select Product.

Click on the drop down against Outlet Stream and select Product.
Click on the drop down against Energy Stream

Select Energy.

Click on the drop down against Energy Stream and select Energy.
Hover mouse at Calculation Parameters Now, Go to Calculation Parameters.
Reaction Set >> Default Set In this section, first option is Reaction Set.

By default, it is Default Set.

Since we have only one reaction, we leave it as it is.

Click drop down against Calculation Mode

Select Isothermic

Click on the drop down against Calculation Mode.

Select Isothermic.

Reactor Volume >> 1 m3

Press Enter

Click on the field against Reactor Volume and enter 1 m3.

Then press Enter.

Reactor Length >> 1 m

Press Enter

Click on the field against Reactor length and enter it as 1 m.

Then press Enter.

Catalyst Loading >> 0.386 kg/m3

Press Enter

Click on the field against Catalyst Loading and enter it as 0.386 kg/m3.

Then press Enter.

Catalyst Particle Diameter >> 2 mm

Press Enter

Click on the field against Catalyst Particle Diameter and enter it as 2 mm.

Then press Enter.

Catalyst Void Fraction >> 0.4

Press Enter

Click on the field against Catalyst Void Fraction and enter it as 0.4.

Then press Enter.

Wait for a few seconds.

The flowsheet is getting simulated.

Once again, we will run the simulation.
Click Solve Flowsheet To do this, click on Solve Flowsheet button.
Click Plug-Flow Reactor When calculations are completed, click on PFR in the Flowsheet.
Hover mouse at Results Locate Results section.
Results >> General Under General tab, Check Residence time.

It is 0.00068 h.

Results >> Conversions Under Conversions tab, check conversion for both the reacting compounds.

For Methane, the conversion is 80.67% and for Water, it is 80.67%.

Insert >> Master Property Table To check the material balances, go to Insert option from the toolbar.

Select Master Property Table.

Double click on Master Property Table

Point to Configure Master Property Table

Double click on the Master Property Table to edit it.

Configure Master Property Table window opens.

Type Stream Wise Results – Heterogeneous Catalytic Reaction Enter the Name as Stream Wise Results – Heterogeneous Catalytic Reaction.
Type Material Stream Enter Object Type as Material Stream.

By default, Material Stream is already selected.

So we will not change it.

Object >> Feed and Product Under Properties to display, select Object as Feed and Product.
Configure Master Property Table>> Property Under Property, select the properties as



Mass Flow

Molar Flow

Mass Flow (Mixture) / Methane

Molar Flow (Mixture) / Methane

Mass Flow (Mixture) / Water

Molar Flow (Mixture) / Water

Mass Flow (Mixture) / Hydrogen

Molar Flow (Mixture) / Hydrogen

Mass Flow (Mixture) / Carbon monoxide

Molar Flow (Mixture) /Carbon monoxide

Mass Flow (Mixture) / Carbon dioxide

Molar Flow (Mixture) / Carbon dioxide

Close this window. Close this window.
Point to the results. Move the Master Property Table for better visibility.

Here we can see the corresponding results for Product and Feed.

Let us summarize.
Slide Number 13


In this tutorial, we have learnt to
  • Define a Heterogeneous Catalytic reaction
  • Define parameters for PFR required to simulate a Heterogeneous Catalytic reaction
  • Find out Conversion and Residence time for Heterogeneous Catalytic reaction in a PFR
Slide Number 14


Water Gas Shift Reaction:

CO + H2O ⇔ H2 + CO2

R2 = [k2/PH2 {PCO PH2O - PH2 PCO2 / K2}] / DEN2

k2 = 1.96 * 10 6 exp (- 67130/RT)

K2 = exp (-3.798 + 4160/T)

As an assignment,

Add two more Heterogeneous Catalytic Reactions for the existing PFR system.

Feed Stream conditions and Plug-Flow Reactor parameters remain unchanged.

Slide Number 15


Overall Reaction:

CH4 + 2H2O ⇔ 4H2 + CO2

R3 = [k3/PH23.5 {PCH4 PH2O2 - PH24 PCO2 / K3}] / DEN2

k3 = 1.02 * 10 15 exp (- 243900/RT)

K3 = exp (34.218 - 31266/T)

Here we give the reaction rates and its coefficients.
Slide Number 16

About the Spoken Tutorial Project

Watch the video available at following link.


It summarizes the Spoken Tutorial project.

Slide Number 17

Spoken Tutorial Workshops

The Spoken Tutorial Project Team* Conducts workshops using spoken tutorials
  • Gives certificates to those who pass an online test
  • For more details, please write to contact@spoken-tutorial.org

Slide Number 18

Forum slide

Do you have questions in this Spoken Tutorial?

Please visit this site

Choose the minute and second where you have the question.

Explain your question briefly.

Someone from the FOSSEE team will answer them.

Please post your times queries in this forum.
Slide Number 19

DWSIM Flowsheeting Project

The FOSSEE team coordinates conversion of existing flow sheets into DWSIM.

We give honorarium and certificates for those who do this.

For more details, please visit this site.

Slide Number 20


Spoken Tutorial and FOSSEE projects are funded by NMEICT, MHRD, Government of India.
Slide Number 21


This tutorial is contributed by Kaushik Datta and Priyam Nayak.

Thanks for joining.

Contributors and Content Editors

Kaushik Datta, Nancyvarkey