Mathematical Modelling of the Desulfurization of Electrolysis Cell Gases in a Low-Temperature Reactor

Abstract

SO2 is one of the main sources of acid rain and air pollution. Semi-dry sorbent injection, using powdered alkaline sorbents, is an effective means of removing SO2. Since no costly additional equipment is needed, the operating cost is lower, and it is a more economical and efficient process compared to wet and dry desulfurization processes. The reaction between sorbent (hydrated lime, Ca(OH)2) and SO2 is dominated by the adsorption step. In this study, a mathematical model has been developed to simulate the lab-scale desulfurization reactor employed for the low-temperature gases containing low SO2 concentration coming from the electrolysis cells used for aluminum production. A parametric study was carried out in order to examine the effects of certain parameters, such as inlet SO2 concentration, sorbent flow rate, and relative humidity of the gas on the desulfurization efficiency. The model and some of the results are presented in this article.KeywordsSO2 removalSemi-dry desulfurizationAluminum electrolysisComputational fluid dynamics (CFD)