Page 345 - Pressure Swing Adsorption
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r  ,
               322                                    PRESSURE SWlNG ADSORPTION        l       APPENDIX B
                                                                                       I
                                                                                       l                                                                    323
               collocauon  points  Z 2 ,  Z_~, ... , ZM+  .  The  exit  velocity  1s  known  from  the   The collocation  form  of the  particle  balance  equations  1s:
                                             1
               specified  boundary  condition.  The  velocity  at  the  column  inlet  may  be
                                                                                                    8xCA (   .              ]
               obtained  by  soivrng the following matrix constructed from  Eq.  B.35:              -- J' IC)  = -,----c;---;--c---....,...,-;-;-        ( B.39)
                                                                                                     ar          1-xCA(J,k)-xc (J,k)
                                                                                                                                 8
                                   1  z,  Z'          zM    g,  "
                        c(2)                2          2
                                   I  z,  Zi         zr     g,
                        i'(3)
                                                                                                                +xCA(J,k) ,~,  B(k,i)xc 8U,i))
                                                                         (B.37)                                           N+!               '
                     "( M + 2)                                                                                                 I
                                                           lM+I                                                 +                         .2
                                                                                                                   [1  -x,j1,k) -XcnC1,k)]



                  B.4.2  Other Steps
               The followmg set Or linear aigebra1c equations 1s  obtained when  EQ.  B.22 and
               the velocity  boundary condit10ns given  by  Eq.  B.25  are  combined  and  wntten
               in  collocat1on  form:


                    ~• [A  (  .. )  _  Ax(M +  2,i)Ax(J,M + 2) ]-(·) _
                                                                                                                + ~t: A( k, i)Xcn(J, i))
                     ,':'2  X J, l    Ax( M  + 2, M  + 2)   V  l   -     (B.38)

                                                                                                    axc"(1,k) =  .  -- '.  YK        .
                                                                                                     a,         t  -,cAll,k) -xc (1,k)                   (B.40)
                                                                                                                                 8
                                                                                                                x([l  -xcA(J,k)l~f B(k,i)xc/l(J,i)


                                                                                                                +xca(1,k) ~t: B(k,i)xCA(J,i))
                         -(·  (.  I)  _  Ax(J, M  +  2)Ax(M +  2, 1)  )-(l) _  .!_  ap
                           AXJ,          Ax(M+2,M+2)         /       p·a,
                                                                                                                +            YK
                                                                                                                  [1-xcA(J,k)  -xc (1,k)]'
                            J =  2, ... , M + I                                                                                    8
                                                                                                                  (             N+ I
                v(M + 2) is  given by Eq.  B.15.  In Eq.  B.33:
                                                                                                                x([l-xcA(J,k)I ,~ A(k,i)xc 8 (1,i)
                     A,= 1/(Ax(J, M  + 2)  - (A Ax(M + 2, M  + 2)]}                                                       N+ I              \
                                             3
                                                                                                                +xc/l(J,k) ,~, A(k,i)xcA(J,i)j
                     A 2 = Ax(M+ 2,M +  2)/(Ax(l,M+2) - [A Ax(M +2,M +  2)]}
                                                            3
                     A 3 =[Ax(l,i)-Peii(l)]/Ax(M+2,l)                                                           X ( ~t: A(k, i)xc8(1, i)
                     A,= 1/Ax(M + 2, 1)                                                                                            l
                                                                                                                  N+ I
                                                                                                                +  L  A(k,i)xcA(1,i)  ,
                                                                                                                  ,. '             I
                                                                                                            J  =  2, ... , M  +  I; k  =  I, ... , N
                    Qm=W/Pe
                                                                                              xcjf, N  + I) and  xcsil, N  + 1)  arc obtained  from  Eos.  B.42  and  B.43.
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