The Effect of Impurities on γ-Alumina Chlorination in a Fluidized Bed Reactor: A CPFD Study

Abstract

Alumina is one of the most widely used materials today, with a total annual production of millions of tonnes of highly pure alumina. A large portion of this is used to make metal aluminum. Apart from that, a growing amount of alumina is used in ceramics, refractories, catalysts, and various other products. In nature, alumina can be found in different phases. These phases can be transformed into each other in different temperatures. Among these, γ-alumina is used in the chlorination process in the aluminum production industry because of the higher reaction rates. Previously, the chlorination of pure γ-alumina has been considered in the CPFD simulations. Extending previous researches, the present study investigates the effect of seven percent α-alumina impurity on the overall chlorination reaction, bed hydrodynamics, and composition of the outflow of the reactor. Commercial CPFD software Barracuda® v20.1.0 is used for the simulations. The results are compared with the pure γ-alumina simulations, and the results show that the impurity has no considerable effect on the chlorine concentration at the outlet. However, the mass balance of the bed shows an unfavorable accumulation of α-alumina in the fluidized bed reactor.