剩余污泥中重金属形态分布及浸出特征研究

Study on Distribution and Leaching Characteristic of Heavy Metals in Surplus Sludge

剩余污泥具有改良土壤结构、增加土壤肥力、促进农作物生长等优点,由于含有有害的重金属等,妨碍其农用。通过对剩余污泥中重金属形态分布及浸出特征研究,结果显示,剩余污泥中Cu、Zn、Ni、Cr及Pb交换态含量都比较少,Cu、Zn、Ni主要以碳酸盐结合态、铁锰氧结合态和硫化物及有机结合态存在,Cr、Cd和Pb主要以残渣态存在;在酸性条件下,交换态、碳酸盐结合态溶出量大,并且溶出量都随浸出时间的延长而增加。

Surplus sludge has the merits improving soil structure,increasing soil fertility,and promoting the growth of crops and so on,because it contains harmful heavy metals such as to hinder its agricultural use.Through the distribution and leaching characteristic research of heavy metals in surplus sludge,the results showed that Cu,Zn,Ni,Cr and Pb exchanged state contents were quite few in surplus sludge,Cu,Zn,Ni mainly associated with carbonate union condition,iron-manganese oxygen union condition and sulfide bound and organic bound existence,Cr,Cd and Pb mainly in residual form there;In acidic condition,the leaching of the exchangeable state,carbonate union condition was big and the leaching increased along with the immersion time extension.