以生污泥为材料,研究单质硫(浓度分别为5、10、20 g/L)、FeSO 4•7H 2 O (浓度分别为10、20 g/L)和硫代硫酸钠(浓度分别为10、20 g/L)三种底物的不同浓度对污泥中Zn、Cu、Pb、Cd、Cr和Ni六种重金属生物淋滤效果的影响。结果表明:单质硫的致酸性最好,第4天pH值就达到2.0左右,Zn、Cu、Pb、Cr和Ni的滤出量最大(原污泥Cd未检出),并以底物投放浓度在10~20 g/L为佳。FeSO 4•7H 2 O的致酸性和重金属滤出量较单质硫弱。硫代硫酸钠在浓度10 g/L时,致酸性和重金属的滤出量介于单质硫和FeSO 4•7H 2 O之间,但浓度20 g/L时滤液呈碱性,重金属难于滤出甚至不滤出。%Bioleaching of six kinds of heavy metals (Zn, Cu, Pb, Cd, Cr and Ni) from sewage sludge with different substrates was studied, adopting S (concentrations of 5, 10 and 20 g/L), FeSO4·7H2O (concentrations of 10 and 20 g/L) and Na2S2O3 (concentrations of 10 and 20 g/L) as substrate. The results showed that acidification of S was best, because pH could reached about 2 at the forth day, and leaching of Zn、Cu、Pb、Cr and Ni achieved the maximum amount at concentrations of 10 and 20 g/L. Acidification and heavy metals leaching amount of FeSO4·7H2O were not as satisfied as that of S. Dealing with Na2S2O3 at the concentration of 10 g/L showed better results than with FeSO4·7H2O, while the concentration of Na2S2O3 was 20 g/L, filtrate was alkaline, heavy metals were difficult to filter out or even not to filter out.
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