Solution of coupled partial differential equations of a packed bed reactor for SO2 removal by lime using the finite element method

Abstract

Lime-based sorbents are extensively used for the throwaway flue gas desulphurization of coal-based power plants. In the present work, the reaction of SO₂ with a single pellet and also a packed bed reactor of conventional and macropore lime was simulated by applying the random pore model. The governing conservation equations for the packed bed reactor are coupled partial differential equations with three independent variables of reactor length, pellet radius, and time. The modeling equations were solved using a finite element solution technique. The results were thoroughly compared with some experimental conversion–time and breakthrough profiles from the literature. Finally, the effects of the pore size distributions of the lime on these profiles were studied to resolve the incomplete conversion problem and achieve a gypsum byproduct.