Page 280 - Pressure Swing Adsorption
P. 280

ii.I
 256   PRESSURE SWING ADSORPTION   PSA  PROCESSES                    257

                                                   -30·90%
                                                      OXYGEN





                                   ZEOLITE
                                                TIME (SECONDS)
                                     II                     0
                                               I 'i.02.I A ~ J
                                  ALUMINA  I   II~
                                                A  - AIR FLOW  (PRODUCT 0 2 )
                                                D1  ~ DESORPTION I  {WASTE)
             ~                                  02 = DESORPTION II  (PRODUCT H2)
     WASTE
       - -'-'---Si-                       (\ - PRESSURIZATION
                                                P
             "v1 i                        I !ii  I COMPRESSOR
                                               I  ct-99.0 +%
                                          ,  (!J
       VACUUM PUMP  ,                    n g r)
                  AIR                         2           NITROGEN
                              1
                              ,    ~_J l z.:c/      c
                              ~V2 '--.._./
                               VACUUM  PUMP
                                      la)
                                                               1000
                   PA  = 840 TORR;  P 0  = 70 TORR
                   TOTAL  DESORBED - 0.507  MOLES /  Kg
         ....                                                  800
         0                  CaX  ZEOLITE                            a:
         :::,                                                       a:
         D                                                          0
         0                                                          ....
         a:
         0..                                                        "'
         z   10                                                     a:
                                                                    :::,
         "'                                                         "'
         (!J
         0    8                                                     "'
         a:                                                    400   "'
         ....
                                                                    a:
         z    6                                                     0.
                                                                    z
         ;;;,                                                       ::,
             4                                                      :::,
          N                                                    200   .J
         0                                                          0
         *    2                                                     0
              0                                                0
              0        0.2       0.4      0.5       0.8      1.0
                            FRACTION  DESORBED  ~
                                      (b)
       Figure  6.24  The  Air  Products  FVSA  a1r  separation  process. '(a) Process  schematic;
                                  3
       (b) performance data. (From  Sircar, ()  with  perm1ss10n.)
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