source: trunk/sample/reactors/fogler/chap6/ammonia_oxidation.mso @ 978

#*--------------------------------------------------------------------
* EMSO Model Library (EML) Copyright (C) 2004 - 2007 ALSOC.
*
* This LIBRARY is free software; you can distribute it and/or modify
* it under the therms of the ALSOC FREE LICENSE as available at
* http://www.enq.ufrgs.br/alsoc.
*
* EMSO Copyright (C) 2004 - 2007 ALSOC, original code
* from http://www.rps.eng.br Copyright (C) 2002-2004.
* All rights reserved.
*
* EMSO is distributed under the therms of the ALSOC LICENSE as
* available at http://www.enq.ufrgs.br/alsoc.
*
*----------------------------------------------------------------------
* Ammonia oxidation in a PFR
*----------------------------------------------------------------------
* Solved problem from Fogler (1999)
* Problem number: 6-8
* Page: 279 (Brazilian edition, 2002)
*----------------------------------------------------------------------
*
*   Description:
*               In a PFR is occuring this simultaneous reaction catalyzed by
*       metal oxide in gas phase:
*                       1: 4NH3 + 5O2 -> 4NO + 6H2O
*                       2: 2NH3 + 1.5O2 -> N2 + 3H2O
*                       3: 2NO + O2  -> 2NO2
*                       4: 4NH3 + 6NO -> 5N2 + 6H2O
*               The rates of reaction to one specific component are known.
*               They are: r1A, r2A, r3B and r4C.
*               The concentration are calculed as function of position in the
*       reactor.
*
*   Assumptions:
*               * change time in reactor volume
*       * steady-state
*       * isotermic and isobaric system
*       * gaseous phase
*
*       Specify:
*               * the inlet stream
*               * the kinetic parameters
*
*----------------------------------------------------------------------
* Author: Christiano D. W. Guerra and Rodolfo Rodrigues
* $Id$
*--------------------------------------------------------------------*#

using "types";


#*---------------------------------------------------------------------
* Example 6-8: in a PFR
*--------------------------------------------------------------------*#

FlowSheet pfr
        PARAMETERS
        NComp           as Integer              (Brief="Number of components");
        NReac           as Integer              (Brief="Number of reactions");
        stoic(NComp,NReac) as Real      (Brief="Stoichiometric coefficients");
        k(NReac)        as Real                 (Brief="Specific velocity reaction");
        Co(NComp)       as conc_mol     (Brief="Input molar concentration");
        vo                      as flow_vol     (Brief="Input volumetric flow");
        
        VARIABLES
        F(NComp)        as flow_mol     (Brief="Molar flow", DisplayUnit='mol/min');
        Fo(NComp)       as flow_mol     (Brief="Input molar flow", DisplayUnit='mol/min');
        C(NComp)        as conc_mol     (Brief="Molar concentration", DisplayUnit='mol/l');
        r(NComp,NReac)as reaction_mol(Brief="Relative rate of reaction", DisplayUnit='mol/min/l');
        rate(NComp) as reaction_mol     (Brief="Overall rate of reaction", DisplayUnit='mol/min/l');
        V                       as volume               (Brief="Reactor volume", DisplayUnit='l');
        
        EQUATIONS
        "Change time in V"
        V = time*'l/s';
        
        "Material balance"
        diff(F) = rate*'l/s';
        
        "Molar concentration"
        C*sum(F) = F*sum(Co);
        
        "Input molar flow"
        Fo = Co*vo;
        
        "Relative rate of reaction 1"
        r(:,1) = stoic(:,1)*(k(1)*C(1)*C(2)^2)*'(m^3/kmol)^2/min';
        
        "Relative rate of reaction 2"
        r(:,2) = stoic(:,2)*(k(2)*C(1)*C(2))*'m^3/kmol/min';
        
        "Relative rate of reaction 3"
        r(:,3) = stoic(:,3)*(k(3)*C(2)*C(3)^2)*'(m^3/kmol)^2/min';
        
        "Relative rate of reaction 4"
        r(:,4) = stoic(:,4)*(k(4)*C(3)*C(1)^(2/3))*'(m^3/kmol)^(2/3)/min';
        
        "Overall rate of reaction"
        rate = sumt(r);

        SET
        NComp = 6;      # 1:ammonia, 2:oxygen, 3:nitrogen oxide, 
                                # 4:water, 5:nitrogen and 6:nitrogen dioxide
        
        NReac = 4;      # 1: 4A + 5B -> 4C + 6D,        2: 4A + 3B -> 2E + 6D
                                # 3: 2C + B -> 2F,                      4: 4A + 6C -> 5E + 6D

        stoic(:,1) = [  -1, -5/4,  1.0, 3/2, 0.0, 0.0]; # A  + 5/4B -> C + 3/2D
        stoic(:,2) = [  -1, -3/4,  0.0, 3/2, 1/2, 0.0]; # A  + 3/4B -> 1/2E + 3/2D
        stoic(:,3) = [   0, -1.0, -2.0, 0.0, 0.0, 2.0]; # B  +   2C -> 2F
        stoic(:,4) = [-2/3,  0.0, -1.0, 1.0, 5/6, 0.0]; # C  + 2/3A -> 5/6E + D
        
        k = [5, 2, 10, 5];
        
        vo = 10*'l/min';
        Co = [1.0, 1.0, 0.0, 0.0, 0.0, 0.0]*'mol/l';
        
        INITIAL
        "Molar flow"
        F = Fo;

        OPTIONS
        TimeStep = 0.1;
        TimeEnd = 10;
end