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.