Page 430 - Modelling in Transport Phenomena A Conceptual Approach
P. 430

410        CHAPTER 9. STEADY MICROSCOPIC BALANCES  WTH GEN.

             Since the volumetric flow rate is not constant, Le., E = 1, it is necessary to express
               in terms of  d. The use of Q.  (9.5146) gives







             Therefore, the total molar flow rate, n, is

                                           h=hAo+i                              (12)

             Substitution  of Eq.  (12) into Eq.  (9.5-151) gives the volumetric flow rate  QS




                                     P

             where e, is the volumetric flow rate at the inlet of  the reactor.
                Substitution  of Eqs.  (9) and  (13) into Eq.  (8) gives

                                     di
                                    -=-   khAo [I - (i/hA,)]
                                     dV     eo  (l+k/fi~,)
             The fractional  conversion  expression for a plug flow reactor is similar to Eq.  (5),
             so



             Substitution  of Eq.  (9) into Eq.  (15) yields
                                                  b
                                            X=--

             The use of  Eq.  (16) in Eq.  (14) and rearrangement  gives



                                      = 2.42 (F)



             Substitution of the nume~cal values into Eq.  (1 7) gives

                                         (2.42) (0.05)
                                    V=              = 0.11 rn3
                                             1.1
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