污泥中氧化亚铁硫杆菌的分离及其应用效果

以FeSO4.7H2O为能源物质,采用9K选择性培养基培养继以Leathen固体培养基平板接种法直接从污泥中分离出一株高度嗜酸的氧化亚铁硫杆菌(Thiobacillus ferrooxidans)菌株该菌株适应污泥环境速度快,易于驯化.序批式试验法研究表明,接种该菌株进行污泥生物淋滤可有效溶出污水污泥中重金属.经过4～10 d的生物淋滤,Cr、Cu、Zn的最高去除率可分别达到80%、100%和100%.

Isolation of Thiobacillus ferrooxidans and Its Application on Heavy Metal Bioleaching from Sewage Sludge

An iron-oxidizing strain, Thiobacillus ferrooxidans, was isolated from sewage sludge through incubation in the 9K-selected liquor medium followed by inoculation in Leathen solid plate. The strain can survive and propagate rapidly in sewage sludge with the addition of ferrous sulfate or sulfur powder as its energy substance. The pH of the sewage sludge inoculated with Thiobacillus ferrooxidans can be reduced to 1.80 from initial 7.86 within 6 days for bioleaching. Compared to the control without the addition of the strain, the treatment with Thiobacillus ferrooxidans exhibited a high ability to oxide Fe2+ and sulfur in the first 6 days during bioleaching. A batch experiment further demonstrated that as high as 100%, 100% and 80% of the removal efficiency of Cu, Zn and Cr in sewage sludge could be obtained, respectively, in the period of 4-10 days bioleaching by using the isolated strain.