城市污水处理用新型有机絮凝剂的制备及性能研究

Preparation and performance study of new organic flocculants for urban sewage treatment

为了提高城市污水的絮凝处理效率,以阳离子单体(丙烯酰氧乙基三甲基氯化铵DAC)、阴离子单体(丙烯酰胺AM)和表面活性单体BA-S为原料,研制出了一种适合城市污水处理用的新型有机絮凝剂PAB-S,优化了其制备条件,对其界面活性和絮凝效果进行了评价。研究结果表明,在单体总浓度为30%、引发剂浓度为0.4%、反应温度为65℃、反应时间为6 h的条件下,制备的新型有机絮凝剂PAB-S综合性能最佳。新型有机絮凝剂PAB-S具有良好的界面活性,对目标城市污水的絮凝处理效果较好,当PAB-S的质量浓度为300 mg/L时,可使油水界面张力降低至21.6 mN/m,对城市污水中的COD去除率可以达到99.1%。另外,在相同的实验条件下,新型有机絮凝剂PAB-S对目标城市污水的处理效果明显优于其他常用絮凝剂。现场应用结果表明,目标城市污水处理厂的二级生化处理工艺出水使用新型有机絮凝剂PAB-S絮凝处理后,COD、BOD5和色度等指标均能达到标准GB/T 8978—1996中的“一级A标准”要求,处理效果较好。

In order to improve the flocculation treatment efficiency of urban sewage,a new organic flocculant PAB-S suitable for urban sewage treatment was developed using cationic monomer(trimethylammonium chloride DAC),anionic monomer(acrylamide AM),and surfactant monomer BA-S as raw materials.The preparation conditions were optimized,and its interfacial activity and flocculation effect were evaluated.The results showed that the new organic flocculant PAB-S with the best comprehensive performance was prepared under the conditions of a total monomer concentration of 30%,initiator concentration of 0.4%,reaction temperature of 65℃,and reaction time of 6 hours.The new organic flocculant PAB-S has good interfacial activity and good flocculation treatment effect on target urban sewage.When the mass concentration of PAB-S is 300 mg/L,the oil-water interfacial tension can be reduced to 21.6 mN/m,and the COD removal rate in urban sewage can reach 99.1%.In addition,under the same experimental conditions,the treatment effect of the new organic flocculant PAB-S on target urban sewage is significantly better than other commonly used flocculants.The on-site application results show that the effluent of the secondary biochemical treatment process of the target city's sewage treatment plant treated with the new organic flocculant PAB-S can meet the requirements of the"Level A Standard"in GB/T 8978—1996 for COD,BOD5,and chromaticity,and the treatment effect is good.