Study On The Process And Kinetics Of SO₂ Catalytic Oxidation By Pyrolusite And Bacterium

Catalysis oxidation of SO₂ by pyrolusite slurry is a new method of flue gas desulphurization. With the reaction time increased, the desulphurization efficiency will be decreased notably. A new idea was proposed that bacteria were added into pyrolusite slurry to renew iron and manganese ion's catalytic activities, for keeping a higher desulphurization efficiency. Catalytic oxidation of SO₂ by pyrolusite and bacterium is a complex system related to mass transfer among gas, liquid and solid phase, chemical reactions including in the aqueous phase, on the surface of solid phase. This paper studied on catalytic oxidation process of SO₂ by pyrolusite slurry, pyrolusite slurry combined with Acidithiobacillus ferrooxidans and Manganese bacteria. The effect of main operation factors on desulphurization and reaction kinetics was also discussed.The 4 kinds of desulphurization processes in pyrolusite slurry system, pyrolusite-Manganese bacteria system, pyrolusite-Acidithiobacillus ferrooxidans system, pyrolusite-mixing of Acidithiobacillus ferrooxidans and Manganese bacteria system were studied. It is shown that Acidithiobacillus and Manganese bacteria promot the oxidation for SO₂ in pyrolusite slurry, but there was an adapting phase to the positive effect of bacterium. The adapting phase is about 20min to Manganese bacteria and 50min to Acidithiobacillus ferrooxidans and mixed cell. The higher bacterium concentration system will cause the higher concentration of...