氧化亚铁硫杆菌对电动力处理城市污泥中重金属影响研究

Effect of thiobacillus ferrooxidans on treatment of heavy metals in sewage sludge by electrokinetics

分析了氧化亚铁硫杆菌对污泥中重金属形态及对电动力处理污泥中重金属的去除率影响。氧化亚铁硫杆菌处理后的污泥,pH值降低,部分重金属从稳定态转化为可溶态。经氧化亚铁硫杆菌预处理后的泥样和未经预处理的泥样,在同样条件下用电动力处理,处理结果为:预处理后Cd的去除率从61.85%上升到72.54%,Cu从34.26%上升到63.51%,Zn从65.06%上升到71.22%。预处理对Cu的影响比Cd、Zn大得多。用电动力处理Cu超标污泥中重金属时,将污泥先用氧化亚铁硫杆菌预处理,可有效地提高其去除效果,处理后的污泥有利于农用。

The influence of thiobacillus ferrooxidans on the speciation of heavy metals in the sewage and the removal efficiencies of heavy metals from sewage sludge by electrokinetics were analyzed . The pH value of the sludge sample pretreated by thiobacillus ferrooxidans was reduced. Because of this, the heavy metals of the sewage sludge were transformed from stable state to labile state. The samples pretreated by thiobacillus ferrooxidans and unpretreated were electroremedied under the same conditions, the results were that the removal efficiencies of Cd raised from 61.85% to 72.54% , Cu from 34.26% to 63.51% , and Zn from 65.06% to71.22%, after pretreatment. The effect of pretreatment by thiobacillus ferrooxidans on Cu was much greater than that on Cd or Zn. The sewage sludge pretreated by thiobacillus ferrooxidans could effectively enhance the removal efficiency of Cu. The electroremedied sludge which was pretreated by thiobacillus ferrooxidans was favorable to land utilization.