Re-evaluation of the background to the Wellman-Lord process

Abstract

This project focuses on the determination of the equilibrium partial pressure of sulphur dioxide above aqueous solutions of sodium sulphite / bisulphite typically found in the absorption section of a Wellman-Lord Flue Gas Desulphurisation (FGD) plant. Data used in the design of the absorption section was that developed by Johnstone in 1938. This study showed that although the general form of his equation describes a method of calculation of the partial pressure, his data was on average 13% lower than that found in this study. Examination of his original data did reveal that a typographical error might have occurred in his paper. Using his new equation would result in an increase in the calculated partial pressure of 26% above that determined from his original equation. Given that Johnstone covered a range of conditions that would not be found in the design of a commercial FGD plant, data developed in this study has been used for all future designs.