重金属废水生物法处理水解渣的分析与综合利用

Analysis and Comprehensive Utilization of Hydrolytic Residue From Biological Treatment of Heavy Metal Wastewater

有色金属冶炼产生的一种含多种重金属的污水,一般为酸性且毒性较强,该污水经生物制剂处理后达标排放,但产生的水解残渣处置不当会造成环境污染。文章分析了水解渣的表面形貌及能谱,结果表明水解渣中无定型物质为重金属离子与生物制剂形成的配合体,晶态物质为碳酸钙,水解渣中锌含量达到20%以上。采用硫酸对水解渣进行锌回收,水解渣高温硫酸浸出最优工艺条件为:酸料比值0.3 mL/g,浸出时间4 h,浸出温度75~85℃。

A kind of sewage containing a variety of heavy metals produced by non-ferrous metal smelting is generally acidic and highly toxic.The sewage is discharged after being treated with biological agents,but the improper disposal of hydrolytic residues will cause environmental pollution.The surface morphology and energy spectrum of hydrolytic residue were analyzed.The results show that the amorphous substance in hydrolytic residue is the complex of heavy metal ions and biological agents,the crystalline substance is calcium carbonate,and the zinc content in hydrolytic residue is more than 20%.Sulfuric acid was used to recover zinc from hydrolyzed residue.The optimal technological conditions for high temperature sulfuric acid leaching of hydrolyzed residue are as follows:acid material ratio 0.3 mL/g,leaching time 4 h,leaching temperature 75~85℃.