# DWSIM/C3/Heterogeneous-Catalytic-Reaction/English

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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 Plug Flow Reactor required to simulate a HCR Calculate Conversion and Residence time for HCR in a PFR Slide Number 3 System Requirements To record this tutorial, I am using DWSIM 5.6 (Classic UI) 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 FOSSEE OS on ARM. Slide Number 4 Pre-requisites 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 https:\\spoken-tutorial.org 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 the 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 4.22E+15*exp(-240100/(8.314*T))/P12.5*((R1*R2)-(P13*P2)/(exp(30.42-27106/T))) 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 (1+6.65E-4*exp(38280/(8.314*T))*R1+8.23E-5*exp(70650/(8.314*T))*P2+6.12E-9*exp(82900/(8.314*T))*P1+1.77E+5*exp(-88680/(8.314*T))*R2/P1)^2 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 at the bottom. Click on Next button at the bottom. 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. 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 button at the bottom. Click on Next button at the bottom. Point to Property Packages Now comes Property Packages. Property Packages >> Available Property Package Double click on Peng-Robinson (PR) From Available Property Packages list, double-click on Peng-Robinson (PR) option. Click on Next button at the bottom. Then click on the Next button at the bottom. 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 let's 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 a 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 under Input Data click on Compound Amounts tab. Basis >> Mole Fractions Choose the Basis as Mole Fractions, if not already selected. By default, Mole Fractions is already selected as 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. Tools >> Reaction Manager Point to Chemical Reactions Manager Under Tools, click on Reactions Manager. Chemical Reactions Manager window opens. 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, type 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 SC Next column is SC (stoichiometric coefficient) Stoich. Coeff >> Methane: -1, Water: -1 Hydrogen: 3, Carbon monoxide: 1, Carbon dioxide: 0' Under SC 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 Type 4.22E+15*exp(-240100/(8.314*T))/P1^2.5*((R1*R2)-(P1^3*P2)/(exp(30.42-27106/T))) We will enter the Numerator part first. Type the equation as shown here. Point to Denominator Type (1+6.65E-4*exp(38280/(8.314*T))*R1+8.23E-5*exp(70650/(8.314*T))*P2+6.12E-9*exp(82900/(8.314*T))*P1+1.77E+5*exp(-88680/(8.314*T))*R2/P1)^2 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 atmosphere from the drop-down. The Reaction Rate is expressed in terms of Partial Pressure, whose unit is atmosphere. 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 the OK button at the bottom. Click on Flowsheet Now go to the 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 a Plug-Flow Reactor(PFR) to the flowsheet Drag and drop a 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 the Calculation Parameters. Reaction Set >> Default Set In this section, the 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 and select Isothermic. Reactor Volume >> 1 m3 Press Enter Click on the field against Reactor Volume and enter 1 m3. and 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. and press Enter. Catalyst Particle Diameter >> 2 mm Press Enter Click on the field against Catalyst Particle Diameter and enter it as 2 mm and 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 the 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%. Let's summarize. Slide Number 13 Summary In this tutorial, we have learnt to Define a Heterogeneous Catalytic reaction Define parameters for Plug Flow Reactor required to simulate a HCR Calculate Conversion and Residence time for HCR in a PFR Slide Number 14 Assignment 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 Assignment 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 and gives certificates. For more details, please write to us. 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 more details, please visit this site. Slide Number 20 TextBook Companion Project The FOSSEE team coordinates coding of solved examples of popular books. We give honorarium and certificates. For more details, please visit this site. Slide Number 21 Lab Migration Project The FOSSEE team helps migrate commercial simulator labs to DWSIM. We give honorarium and certificates. For more details, please visit this site. Slide Number 22 Acknowledgements Spoken Tutorial and FOSSEE projects are funded by NMEICT, MHRD, Government of India. Slide Number 23 Thanks This tutorial is contributed by Kaushik Datta and Priyam Nayak. Thanks for joining.