氧化锰共生矿烟气脱硫的机理及影响因素

Mechanism and influence factors of flue gas desulfurization by symbiotic manganese oxides ore

利用南非的氧化锰共生矿进行烟气脱硫,研究了共生锰矿烟气脱硫性能及其机理,并考察了锰矿粒径、反应温度、液固比、进气流量、进口SO_2浓度等因素对脱硫率的影响。结果表明,氧化锰共生矿中主要的锰化合物是MnO_2、Mn_2O_3和MnCO_3,烟气脱硫过程主要存在4种方式:MnO_2与SO_2发生氧化还原反应生成硫酸锰;液相中Mn^(2+)催化氧化SO_2产生硫酸;MnCO_3与硫酸反应生成硫酸锰;Mn_2O_3与硫酸反应后生成的MnO_2可以继续与SO_2进行脱硫反应,但是Mn_2O_3与SO_2直接反应的活性较差。氧化锰共生矿烟气脱硫的最佳工艺参数为:锰矿粒径200目、反应温度80℃、液固比10:1以及进气流量600mL·min^(-1)。

The symbiotic manganese oxides ore was applied to remove sulfur dioxide from flue gas. The desulfurization performance and mechanism of symbiotic manganese oxides ore was studied. The effects of ore particle size, reaction temperature, liquid-solid ratio, inlet gas flow and SO2 inlet concentration on the desulfurization efficiency were determined.The results showed that the symbiotic manganese oxides ore include mainly MnO2, Mn2 O3, MnCO3, and there are mainly four processes for desulfurization： the oxidation-reduction reaction between MnO2 and SO2 into manganese sulfate, the catalytic oxidation of SO2 into sulfuric acid by Mn^（2＋）, in solution, the reaction between MnCO3 and H2 SO4 and the reaction between Mn2 O3 and H2 SO4 into MnO2 which could further react with SO2, while the reaction activity of Mn2 O3 with SO2 was much worse. The optimal parameters for its desulfurization were obtained as follows： the particle size of ore at 200 meshes, the reaction temperature at 80 °C, the ratio of liquid to solid at 10 ： 1 and the inlet gas flow rate at600 mL·min^（-1）.