电化学处理改善垃圾沥滤液生化出水的微滤性能

Enhancement of micro-filtration capacity for biochemically treated effluent from garbage leachate by electrochemical oxidation process

垃圾沥滤液生化出水中的胶体物质含量较高,采用膜技术进行深度处理时膜污染问题比较严重。采用电化学氧化法对垃圾焚烧发电厂沥滤液生化出水中的胶体物质进行脱除处理,以改善其过滤性能。结果表明:电流密度为2×10-2A/cm2时,电化学处理时间、比电极面积、处理后废水的静置时间都会影响处理后废水的过滤性能。适宜的处理条件:电化学处理时间为15 min,比电极面积为30.4 m2/m3,处理后废水的静置时间为24 h。在此条件下处理废水,过滤通量显著增加。电化学处理后废水中的COD和余氯随静置时间的延长呈不断降低趋势。废水中的余氯在静置过程中可破坏废水中的胶体物质,分解废水中的有机物,在降低COD的同时改善废水的过滤性能。

Colloidal substances in garbage leachate biochemical effluent is rather high. The membrane fouling prob- lem is rather serious when membrane technology is used in advanced treatment. Electrochemical oxidation process has been used for removing this kind of colloidal substances in garbage leachate effluent from burning power plants, so as to improve its filtration capacity. The results show that when its current density is 2×10^-2A/cm2,electrochemical treatment time, specific electrode area and wastewater setting time after treatment can all affect the filtration capacity of the treated wastewater. Optimal treatment conditions are as follows：electrochemical treatment time is 15 min, specific electrode area 30.4 m2/m3, and wastewater setting time after treatment is 24 h. Under these conditions, the filtration flux can be increased significantly. After electrochemical treatment,the COD in wastewater and residual chloride decreases continuously along with the extension of setting time. The residual chloride in wastewater has de- structive effect on colloidal substances in the course of setting,decomposing the organisms in water. The filtration capacity of wastewater can be improved at the same time whille its COD is decreasing.