SO2 Removal by Seawater in a Packed-Bed Tower: Experimental Study and Mathematical Modeling

Flue gas desulfurization of industrial plants using seawater is studied experimentally and theoretically in a counter-current packed-bed tower. Experiments are carried out based on a 16-run orthogonal array of the Taguchi method (five factors, four levels) and ANOVA table created to determine the most significant controlling factors on SO2 removal efficiency. Liquid flow rate (1.5-4 l/min), gas temperature (50-350 degrees C), gas flow rate (8-20 m(3)/h), and SO2 concentration (500-2000 ppmv) are revealed as important factors, while the pH of seawater (8-9.5) is not significant. Experimental results show that an increase in gas temperature causes a decrease in the removal efficiency. A mathematical model is developed for the removal of SO2 by seawater for non-isothermal operating conditions. In the modeling procedure the equilibrium reactions of eight dissolved species within the liquid phase are considered to calculate the kinetic of reaction correctly. The results of this study confirm the capability of seawater for SO2 removal in packed-bed towers.