固定化SRB污泥处理含镉离子废水

摘要

Immobilized beads of sulfate-reducing bacteria (SRB) were prepared by the method of PVA-(NH4)2SO4 immobilization.The effect of reaction time,initial concentration of Cd(Ⅱ),mass ratio of beads to liquid,initial pH,temperature on its treatment of wastewater containing Cd (Ⅱ) were investigated,mechanism of Cd(Ⅱ) removal was elucidated.The results show that the removal rate of Cd(Ⅱ) reaches 99.2％ when reaction time is 24 h,initial concentration of Cd(Ⅱ) is 100 mg/L,mass ratio of beads to liquid is 1∶ 5,initial pH is 7,temperature is 30 ℃.Cd2+ removal is the result of deposition of Cd2+ and S2-.%利用聚乙烯醇-硫酸铵包埋法制备了硫酸盐还原菌(SRB)污泥固定化小球,考察了反应时间、初始镉浓度、球液配比量、初始pH值、温度等因素对处理含镉废水效果的影响,阐明了其去镉机理.结果表明,在Cd2+的质量浓度为100 mg/L,球液比为1∶5,初始pH为7.0,温度为30℃,反应时间为24h的条件下处理含镉废水,镉离子去除率达到99.2％；镉离子主要与SRB的代谢产物S2-形成CdS沉淀,从废水中去除.