无机-有机复合混凝剂处理夏季引黄水库水的对比研究

摘要

合成了具有不同Fe(Al)/聚二甲基二烯丙基氯化铵(PDMDAAC)质量比的无机-有机复合混凝剂PFC-PDMDAAC和PAC-PDMDAAC,并对夏季引黄水库水进行混凝处理.考察了复合比例、投药量、pH值和投加方式对浊度、有机物和叶绿素-a的去除效果；并通过混凝过程中形成絮体的Zeta电位的变化分析了2种混凝剂的混凝机理.结果表明,无机-有机复合混凝剂处理夏季引黄水库水的效果好于2种单独成分的复配使用；复合比例对PFC-PDMDAAC和PAC-PDMDAAC处理夏季引黄水库水的效果影响较大,Fe(Al)/PDMDAAC质量比为4∶1,投药量为4mg/L时混凝效果最好；与无机混凝剂相比,复合混凝剂的最佳pH值范围较广,可在5.0～8.0的pH值范围内取得良好的混凝效果；2种混凝剂相比,AC-PDMDAAC对浊度和叶绿素-a的去除效果较好,而PFC-PDMDAAC对有机物的去除效果更佳.%Two inorganic-organic composite coagulants PFC-PDMDAAC and PAC-PDMDAAC with series of Fe(Al)/PDMDAAC mass ratios were prepared for treatment of summer reservoir raw water from the Yellow River. The influence of Fe(Al)/PDMDAAC mass ratios, dosage, pH and dosing order on coagulation effect (turbidity, organic matter and chlorophyll-a removal) was investigated. The coagulation mechanism of the two coagulants was analyzed by the variation of Zeta potential during coagulation processes. The composite coagulants performed better than using them as dual-coagulants. The coagulation effects of both composite coagulants were greatly impacted by the mass ratio of Fe (A1)/PDMDAAC. The best coagulation effects were obtained when Fe (A1)/PDMDAAC mass ratio was 4:lwith the dosage of 4mg/L. The composite coagulants could give excellent coagulation effect in the pH range from 5.0to 8.0, which is much wider than the inorganic coagulants. In comparison of PFC-PDMDAAC, PAC-PDMDAAC gave better turbidity and chlorophyll-a removal and worse organic matter removal.