| 1 | #*------------------------------------------------------------------- |
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| 2 | * EMSO Model Library (EML) Copyright (C) 2004 - 2007 ALSOC. |
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| 3 | * |
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| 4 | * This LIBRARY is free software; you can distribute it and/or modify |
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| 5 | * it under the therms of the ALSOC FREE LICENSE as available at |
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| 6 | * http://www.enq.ufrgs.br/alsoc. |
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| 7 | * |
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| 8 | * EMSO Copyright (C) 2004 - 2007 ALSOC, original code |
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| 9 | * from http://www.rps.eng.br Copyright (C) 2002-2004. |
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| 10 | * All rights reserved. |
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| 11 | * |
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| 12 | * EMSO is distributed under the therms of the ALSOC LICENSE as |
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| 13 | * available at http://www.enq.ufrgs.br/alsoc. |
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| 14 | * |
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| 15 | *--------------------------------------------------------------------- |
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| 16 | * Hidrodesalkylation of mesitylene |
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| 17 | *---------------------------------------------------------------------- |
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| 18 | * Solved problem from Fogler (1999) |
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| 19 | * Problem number: 6-6 |
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| 20 | * Page: 273 (Brazilian version, 2002) |
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| 21 | *---------------------------------------------------------------------- |
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| 22 | * |
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| 23 | * Description: |
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| 24 | * Sample to calculate of the molar concentration as functions of |
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| 25 | * the resident time in a PFR with a fixed bed. There is the reaction |
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| 26 | * of hidrodesalkylation of mesitylene: |
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| 27 | * mesitylene + H2 -> m-xylene + CH4 |
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| 28 | * m-xylene + H2 -> toluene + CH4 |
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| 29 | * |
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| 30 | * Assumptions: |
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| 31 | * * change time in residence time |
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| 32 | * * steady-state |
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| 33 | * * isotermic and isobaric system |
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| 34 | * * gaseous phase |
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| 35 | * |
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| 36 | * Specify: |
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| 37 | * * the inlet stream |
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| 38 | * * the kinetic parameters |
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| 39 | * * the parameters of reactor |
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| 40 | * |
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| 41 | *---------------------------------------------------------------------- |
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| 42 | * Author: Christiano D. W. Guerra and Rodolfo Rodrigues |
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| 43 | * $Id: hidrodesalkeletion.mso 188 2007-03-07 16:53:12Z rodolfo $ |
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| 44 | *--------------------------------------------------------------------*# |
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| 45 | |
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| 46 | using "types"; |
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| 47 | |
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| 48 | |
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| 49 | #*--------------------------------------------------------------------- |
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| 50 | * Example 6-6: in a PFR |
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| 51 | *--------------------------------------------------------------------*# |
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| 52 | |
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| 53 | FlowSheet pfr |
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| 54 | PARAMETERS |
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| 55 | NComp as Integer (Brief="Number of components", Default=1); |
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| 56 | NReac as Integer (Brief="Number of reactions"); |
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| 57 | stoic(NComp,NReac) as Real (Brief="Stoichiometric coefficients"); |
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| 58 | k(NReac) as Real (Brief="Specific velocity reaction", Unit='(ft^3/lbmol)^.5/h'); |
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| 59 | P as pressure (Brief="Pressure of reactor"); |
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| 60 | T as temperature (Brief="Temperature of reactor"); |
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| 61 | R as Real (Brief="Universal gas constant", Unit='atm*ft^3/degR/lbmol', Default=0.73); |
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| 62 | yo(NComp) as fraction (Brief="Input molar fraction"); |
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| 63 | vo as flow_vol (Brief="Input volumetric flow"); |
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| 64 | |
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| 65 | VARIABLES |
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| 66 | F(NComp) as flow_mol (Brief="Molar flow", DisplayUnit='lbmol/h'); |
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| 67 | C(NComp) as conc_mol (Brief="Molar concentration", Lower=0, DisplayUnit='lbmol/ft^3'); |
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| 68 | Co(NComp) as conc_mol (Brief="Input molar concentration", Lower=0, DisplayUnit='lbmol/ft^3'); |
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| 69 | |
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| 70 | r(NComp,NReac) as reaction_mol (Brief="Relative rate of reaction", DisplayUnit='lbmol/h/ft^3'); |
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| 71 | rate(NComp) as reaction_mol (Brief="Overall rate of reaction", DisplayUnit='lbmol/h/ft^3'); |
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| 72 | tau as time_h (Brief="Residence time", DisplayUnit='h'); |
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| 73 | V as volume (Brief="Reactor volume", DisplayUnit='ft^3'); |
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| 74 | |
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| 75 | EQUATIONS |
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| 76 | "Change time in tau" |
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| 77 | tau = time; |
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| 78 | |
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| 79 | "Molar balance" |
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| 80 | diff(C) = rate; |
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| 81 | |
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| 82 | "Molar flow" |
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| 83 | F = vo*C; |
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| 84 | |
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| 85 | "Inlet molar concentration" |
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| 86 | Co = yo*P/R/T; |
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| 87 | |
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| 88 | "Residence time" |
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| 89 | tau = V/vo; |
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| 90 | |
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| 91 | "Relative rate of reaction 1" |
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| 92 | r(:,1) = stoic(:,1)*k(1)*C(1)*sqrt(C(2)); |
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| 93 | |
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| 94 | "Relative rate of reaction 2" |
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| 95 | r(:,2) = stoic(:,2)*k(2)*C(3)*sqrt(C(2)); |
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| 96 | |
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| 97 | "Overall rate of reaction" |
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| 98 | rate = sumt(r); |
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| 99 | |
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| 100 | SET |
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| 101 | NComp = 5; # 1: mesitylene, 2: hydrogen, 3: m-xylene, |
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| 102 | # 4: methane and 5: toluene |
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| 103 | |
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| 104 | NReac = 2; # 1: M + H -> X + Me, |
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| 105 | # 2: X + H -> T + Me |
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| 106 | |
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| 107 | stoic(:,1) = [-1.0, -1.0, 1.0, 1.0, 0.0]; # M + H -> X + Me |
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| 108 | stoic(:,2) = [ 0.0, -1.0, -1.0, 1.0, 1.0]; # X + H -> T + Me |
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| 109 | |
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| 110 | vo= 476*'ft^3/h'; |
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| 111 | T = 1500*'degR'; |
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| 112 | P = 35*'atm'; |
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| 113 | yo= [1/3, 2/3, 0.0, 0.0, 0.0]; |
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| 114 | k = [55.2, 30.2]*'(ft^3/lbmol)^.5/h'; |
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| 115 | |
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| 116 | INITIAL |
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| 117 | "Molar concentration" |
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| 118 | C = Co; |
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| 119 | |
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| 120 | OPTIONS |
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| 121 | TimeStep = 0.01; |
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| 122 | TimeEnd = 0.5; |
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| 123 | TimeUnit = 'h'; |
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| 124 | end |
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