生物还原-化学沉淀去除烟气SO2中Na2 SO3和硫化物的研究

利用硫酸盐还原菌（SRB）和金属离子沉淀剂对烟气SO2进行生物还原-化学沉淀去除，考察了碳源类型、乙酸（碳源）浓度、沉淀剂投加量和反应时间对SO3^2-去除的影响，研究表明，沉淀剂的加入导致SRB转化产生的S^2-能很快生成硫化物沉淀，其它副反应被抑制．乙酸C原子／SO3^2-的浓度比为1时，SO3^2-去除最大．随着沉淀剂投加量的增加，SO3^2-去除率增大．ZnCl2生化反应培养14d后，SO3^2-去除趋于完全．FeCl2生化反应培养7d后，SO3^2-去除趋于完全．

REMOVAL OF SO2 BY COMBINED PROCESSES OF MICROBIAL DEOXIDIZATION AND CHEMICAL PRECIPITATION

In this paper, removal of SO2 and production of sulfide by combined processes of microbial deoxidization and chemical precipitation were proposed. The effects of carbon-source type, acetic-acid concentration, precipitant dosage and reaction time on SO3^2- removal were investigated. The results showed that presence of precipitant causes quick generation of sulfide precipitate due to chemical precipitation between metal ion and S^2- from SO3^2- reduction by SRB, inhibiting the other reaction of S^2-. It is optimum for the SO3^2- removal that molecular concentration rate between acetic-acid C and SO3^2- equal to one. SO3^2-removal increases with the increase in precipitant dosage. The reaction for SO3^2-removal approaches to finish after 14 day incubation when the precipitant was ZnCl2. The reaction for SO3^2- removal approaches to finish after 7 day incubation when the precipitant was FeCl2.