絮凝剂投加量及配比对臭氧氧化后剩余污泥脱水特性的影响

Influence of Flocculant Dosage and Ratio on Dewatering Characteristics of Residual Sludge after Ozone Oxidation

臭氧氧化是污泥处理时常用的减量化、资源化技术。过往的研究表明,氧化后的污泥脱水能力变差,需要投加絮凝剂来改善污泥特性。然而,目前关于絮凝剂的最佳投加量与配比的研究较少。研究以上海市某污水处理厂二沉池污泥为对象,通过小试试验研究聚合氯化铝(PAC)与阳离子聚丙烯酰胺(CPAM)投加量与配比对污泥脱水能力的影响,确定了最佳投加量。试验结果表明,臭氧氧化2 h时,投加3%的PAC与0.4%的CPAM,污泥脱水能力达到最佳;超过最佳投加量后,继续投加絮凝剂会造成污泥脱水能力的恶化。研究可为生产中污泥脱水前絮凝剂的投加提供参考。

Ozone oxidation is a commonly used reduction and resource technology in sludge treatment. Past research has shown that the dewatering ability of the oxidized sludge becomes poor, and flocculants need to be added to improve the sludge characteristics. However, there are few studies on the optimal dosage and ratio of flocculants. In this study, taking the sludge of a secondary sedimentation tank of a WWTP in Shanghai as the object, the effect of the dosage and ratio of polyaluminum chloride(PAC) and cationic polyacrylamide(CPAM) on the dewatering performance of the sludge was studied through a small test, and the optimal dosage was determined. The test results showed that when ozone was oxidized for 2 h, adding 3% PAC and 0.4% CPAM could achieve the best sludge dewatering performance. After the optimum dosage was exceeded, the continuous dosage of flocculant would cause the deterioration of sludge dewatering performance. The research can provide reference for the dosage of flocculant before sludge dewatering in production.