Page 346 - 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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