重金属离子对活性污泥处理污水的影响

Effect of heavy metal ions on wastewater treatment with activated sludge

研究了Hg2+、Cd2+、Pb2+3种金属离子对活性污泥系统处理污水效能的影响。通过对出水理化指标和生物指标的测定反映Hg2+、Cd2+、Pb2+对活性污泥系统运转效能的影响。结果表明:实验第4 d,Hg2+(0.3、0.4、0.5和0.6 mg/L),Cd2+(15、20、25和30 mg/L)和Pb2+(300、400、600和800 mg/L)各实验组出水的COD、SVI等均有显著影响。在实验中得出,对COD影响最为明显的为浓度600 mg/L和800 mg/L Pb2+实验组,在第4 d时,出水的COD去除率已经为零。锐利楯纤虫对Hg2+的浓度变化耐受力较强;点钟虫对Cd2+的浓度变化耐受力较强;杯钟虫对Cd2+的浓度变化耐受力较强。锐利楯纤虫对Pb2+和Cd2+的浓度变化较为敏感;点钟虫对Hg2+的浓度变化较为敏感;小口钟虫对Pb2+的浓度变化较为敏感。

This research mainly focused on effect of Hg^2＋,Cd^2＋ and Pb^2＋ on the sewage treatment with activated sludge.And the effect would be reflected by outlet physicochemical index and biological index. The results showed that Hg^2＋（0.3、 0.4、 0.5 and 0.6 mg/L）,Cd^2＋（15、20、 25 and 30 mg/L、） and Pb^2＋（300、400、600 and 800 mg/L） in all experimental groups exert significant effect on COD and SVI on the fourth day.The removal rate of COD in groups of Pb^2＋ at 600 mg/L and 800 mg/L was zero on the fourth day.It could be inferred from the experiment that Aspidisca lynceus＇s ability to resist toxicity of Hg^2＋,Vorticella picta＇s ability to resist toxicity of Cd^2＋ and Vorticella cupifera＇s ability to survive toxicity of Cd^2＋ was good;Aspidisca lynceus was sensitive to concentration variation of Pb^2＋ and Cd^2＋;Vorticella picta was sensitive to concentration variation of Hg^2＋;Vorticella microstoma was sensitive to concentration variation of Pb^2＋.