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Else_AIEC-INGLE_cH004.qxd  7/1/2006  6:53 PM  Page 299
                  4.2 Design of Adsorption and Ion-Exchange Processes  299


                  where   La  can be calculated by using eq. (4.8):


                                                    1
                                             La           0.1873
                                                 1  KC    o


                  Then, a trial-and-error procedure is needed for estimating the equilibrium liquid-phase
                  , dimensionless concentration. In this w we get  ay  X = 0.1 and thus


                                           C
                                        X    e    C  e  C X    o    9.975    mg/L
                                           C  o

                  The parameter   w is calculated by using eq. (4.33):


                                                  C  C
                                              w    o   e    0.9
                                                    C  o


                  Then, the roots of eq. (4.58) are   a = –3.477 and   b  = 0.777. To use the model, we need to
                  transform the solid loading   q into   U ( t ):
                                         t

                                                     C
                                                       C t ()
                                               Ut ()    o
                                                     C  o  C    e
                  where the liquid concentration   C ( t ) can be calculated from the follo wing relationship:


                                                   C  C t   ()
                                               q    o      V
                                                t
                                                      m
                  In Table 4.22,  t and the corresponding v alues of   U ( t ) are gi en. v



                                                  Table 4.22
                                                 U ( t ) v ersus   t
                                        t (min)                  U(t)

                                        15                     0.22
                                        30                     0.27
                                        60                     0.36
                                        120                   0.47
                                        180                   0.56
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