直流电解对剩余污泥中氮、磷及重金属影响研究

The Research of Removal of Nitrogen, Phosphorus and Heavy Metals from Excess Sludge by DC Electrolysis

城镇污水厂剩余污泥的去向引起了业内的广泛关注,剩余污泥富含营养物质有利于其资源化利用,但需要对其中重金属进行管控。采用直流电解法处理剩余污泥,实验表明,电解反应在电压7 V,电流7 A,电解25 min时,污泥上清液中SCOD从312 mg/L增加到747.67 mg/L,TN从39 mg/L增加到196.69mg/L,TP从122.09 mg/L降低至2.2 mg/L;污泥中Cu的含量从106.2mg/kg降到55.1mg/kg,Zn的含量从276.45 mg/kg降到106.2 mg/kg。实验结论表明利用直流电解技术处理剩余污泥,使污泥中的营养物质得到释放,Cu,Zn元素有效去除,为剩余污泥的利用提供有利前提。

The fate of excess sludge in urban sewage plants has caused widespread concern in the industry. Rich nutrients are beneficial to the utilization of sludge, but it is necessary to control the heavy metals in the sludge and comprehensive safety. This paper uses DC electrolysis to treat excess sludge. The result of experiments shows that the electrolysis reaction increases the SCOD from 312 mg/L to 747.67 mg/L and the TN from 39 mg/L to 196.69 mg/L at 7 V, 7 A, and 25 min. Meanwhile, TP decreased from 122.09 mg/L to 2.2 mg/L. In addition, the content of Cu in the sludge dropped from 106.2 mg/kg to 55.1 mg/kg, and the content of Zn dropped from 276.45 mg/kg to 106.2 mg/kg. The experimental results show that the DC sludge is used to treat the excess sludge, so that the nutrients in the sludge are released, the Cu and Zn elements are effectively removed, which provides a favorable premise for the utilization of excess sludge.