Cofeed FBR vs. Distributed Dosing of Reactants PBMR Nonreactive Conditions

Cofeed (FBR) vs. Distributed Dosing of Reactants (PBMR) - Nonreactive Conditions 

Before discussing the reactor performance in the presence of chemical reactions, it is instructive to consider the main differences between FBR and PBMR in the residence-time behavior and in the local component concentration profiles caused by the differences in dosing strategy. In accordance with the case study illustrated in Fig. 5.2, ethane and oxygen will be considered as two feed components. Both can be dosed together at the reactor inlet (FBR) or in a distributed manner (PBMR). In both cases it is assumed at first that no reactions take place between them. In the case of the PBMR it is further assumed that there is a uniform dosing profile, i.e. f = const. The set of simulation parameters used in the present study is summarized in Table 5.2. In the following it is referred as the standard parameter set . 

The reactant mass fractions in the PBMR, , are related below to the overall feed according to Eq. (5.5) and can be translated easely into concentration units 

Reactor length (length of the porous zone) - L 60mm 

Note that there are also several experimental studies concerning the effect of residence-time distribution and local concentration profiles on the integral performance of a PBMR available (Tonkovich et al., 1996a Pena et al., 1998 Klose et al, 2004b). 

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