A Simple Model for the Bubbling Fluidized Bed Reactor

It is outside the scope of this chapter to review in detail the models available for the fluidized bed as a reactor. However, in order to demonstrate the key components of such models, we will use the simple model of Orcutt et al. (1962). Although simple, this model allows the key features of a fluidized bed reactor for gas-phase catalytic reaction to be explored. 

In steady state, the concentration of reactant in the particulate phase is constant throughout the particulate phase because of the assumption of perfect mixing in the particulate phase. Throughout the bed, gaseous reactant is assumed to pass between particulate phase and bubble phase. 

Term (2) molar reactant flow in bubble phase changes with height L above the distributor as gas is exchanged with the particulate phase. Consider an element of bed of thickness 5L at a height L above the distributor. In this element  

Term (4) For a reaction which is jth order in the reactant under consideration. 

Substituting these expressions for terms (l)-(4), the mass balance becomes  

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