不同浸提剂pH对工业污水污泥中重金属浸出的影响

在研究工业污水污泥中6种重金属（Zn、Cu、Pb、Cr、Mn、Ni）含量的基础上，应用固体废物浸出毒性的浸出方法（GB5086．2-1997）以不同pH值的浸提剂对污泥中重金属的浸出特性进行了实验研究。结果表明：污泥中Mn和Zn含量较高，其次为Cu和Ni，而毒性较大的Pb和Cr含量较低。浸提剂的pH对污泥中重金属的浸出具有重要的影响，其中污泥中的Zn、Mn、Ni、Cu最大浸出量在pH为7左右，而Fe则有较大的波动。不同pH值中金属的浸出量有很大的差异，这可能与浸提过程中的吸附一解吸过程、络合一解离过程和溶解一沉淀／共沉淀等因素有关。

Experimental Study on Influence of pH Value of Extractant on the Leachability of Heavy Metals in Sewage Sludge Consist of Industrial Wastewater

The leaching tests of heavy metals in sewage sludge consist of industrial wastewater were conducted under different pH values of extractant by employing the ＂solid waste extraction procedure for leaching toxicity（GBS086.2-1997）＂ of China in the base of the contents of Zn, Gu, Pb, Cr, Mn, Ni elements. The results showed that the sludge with higher levels of Mn and Zn, followed by Cu and Ni, while the higher toxicity of Pb and Cr is low. The fractions of different elements in the sewage sludge have very different combination forms. The pH values of extraction agents have an important impact on the leaching of heavy metals in sewage sludge, in which the Zn, Mn, Ni, Cu leaching volume of the largest in the pH of 7 and Fe has a greater fluctuation. Different pH values of the leaching amount of metals have very different, which may be related with the process of adsorption/desorption, complexation/ dissociation and the dissolution/precipitation/co-precipitation and other factors, and their leaching mechanism requires further study.