Study on SO2 Absorption Characteristics in Two-stage Wet Desulfurization Process

Abstract

The effect of the inlet SO2 concentration and the pH of the desulfurization slurry on the SO2 absorption efficiency was systematically studied on a two-stage falling film reactor test system. Studies have shown that the SO2 absorption efficiency has a positive correlation with the pH value of the slurry. In the entire pH range, the SO2 absorption efficiency increases with the increase of the pH value and decreases with the increase of the SO2 concentration, but in different pH value areas. the main influencing factors for controlling the SO2 absorption efficiency are different. In the low pH range(3.5∼5.5), the SO2 absorption efficiency is mainly controlled by the inlet SO2 concentration, and the pH value is a secondary factor. However, in the high pH area(5.5∼6.5)the SO2 absorption efficiency is mainly controlled by pH when the inlet SO2 concentration is≤4000mg/m3. When the inlet SO2 concentration is >4000mg/m3, the SO2 absorption efficiency is controlled by the inlet SO2 concentration and pH value.