微污染地表水的胞外聚合物复合絮凝剂强化混凝处理

Decontamination of Micro-pollution Water by Enhanced Coagulation with Multiplex Flocculants of Extracellular Polymeric Substances

采用胞外聚合物作为生物絮凝剂,开展胞外聚合物复合絮凝剂强化混凝处理微污染原水的研究。研究结果表明,蛋白质是胞外聚合物最主要的成分,多糖次之,腐殖酸和脱氧核糖核酸的含量最低;胞外聚合物含有大量带负电荷的官能团,单独投加胞外聚合物不能有效絮凝和吸附去除原水中的污染物。聚合氯化铝混凝处理微污染水的效果优于氯化铝和聚合硫酸铁,药品较优投加质量浓度为70-80 mg/L。胞外聚合物和聚合氯化铝复合使用能提高对细小颗粒物的去除效果,增强去除有机污染物和氯化消毒副产物前驱体的能力,降低聚合氯化铝的质量浓度。胞外聚合物复合絮凝剂的较优配方:胞外聚合物质量浓度为5 mg/L,聚合氯化铝质量浓度为60 mg/L。

Taking extracellular polymeric substances （EPS） as biological flocculants, the decontamination of micro-pollution water by enhanced coagulation with multiplex flocculants of EPS has been studied. Results show that proteins are the main component of EPS, followed by carbohydrate, and humic acids and DNA are the least. In the course of coagulation, only adding EPS could not effectively flocculate and absorb pollutants in water,which containing a great deal of negative function groups. The effect of coagulation treating micro-pollution water with poly-aluminum chloride （PAC） is better than that with aluminum chloride, or poly-ferric sulfate （PFS）, and the optimum mass concentration of agents added into the water is 70-80 mg/L. The coagulation treatment with both EPS and PAC could enhance removal effect of micro-particle, organic pollutants and chlorine disinfection byproducts, and decrease the addition dose of PAC.The optimum of multiplex flocculants containing EPS is that the mass concentration of EPS is 5 mg/L, and that of PAC is 60 mg/L.