Page 488 - Elements of Chemical Reaction Engineering Ebook
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Sec. 8.:3   Nonisothermal Continuous-Flow Reactors             459

                                    Recalling Equation  (8-47) and ignoring any  work  done on  the reacting
                                fluid, 'we obtain

                                             T
                                     IO-FAOI   COjC,jdT-                           FAoX=O  (13-54)
                                             TO
                                Differientiating with respect to the volume V and collecting terms gives us










                                Recalling  that  -'A   = FAo (dXldV), and  substituting  Equation  (8-44)  for
                                (dQldV), we can rearrange Equation (8-55) to obtain


                 Energy balance on
                    PER with heat                                                            (8-56)
                         transfer

                   Energy balance  The differential equation  describing the  change of  temperature with  volume
                                (i.e., distance) down the reactor,




                       Numerical
                 integration of two
                coupled differential  must he coupled with the mole balance,
                      equations is
                        required
                    Mole balance
                                                       I                    1
                                and solved simultaneously. A variety of  numerical integration schemes can be
                                used to solve these two equations simultaneously.

                                Energy Balance in Measures Other Than Conversion.  If we work in tm-ms
                                other than conversion, we derive an equation similar to Equation (8-56) by first
                                differentiating Equation @-lo),

                                                           n           n
                                                  Q-Wx+       F,,Hi0-  2 FiH, = 0            (8-10)
                                                          i=l         i=l
                                with respect to the volume, V:

                                                                                             (8-57)
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