不同铝形态去除水中腐殖酸的混凝特性  

Coagulation Characteristics of Different Al Species on Humic Acid Removal from Water

作　　者：吴珍[1] 张盼月[1] 曾光明[1] 高英[2] 肖辉煌[1] 周凡[1] 

机构地区：[1]湖南大学环境科学与工程学院,长沙410082 [2]中国地质大学地球科学与资源学院,北京100083

出　　处：《环境科学》2008年第7期1903-1907,共5页Environmental Science

基　　金：教育部新世纪优秀人才支持计划项目(531105050030);教育部留学回国人员基金项目(757210005)

摘　　要：制备了碱化度为2.4、以Al13为主要成分的聚合铝PAC-Al13和碱化度为2.4、以Al30为主要成分的高聚聚合铝PAC-Al30.采用烧杯混凝实验,通过絮体颗粒生长、电中和能力、pH和混凝剂投量对混凝效果的影响,比较了PAC-Al30、PAC-Al13和AlCl3混凝去除水中腐殖酸的行为,并考察了水中残留铝的含量.实验结果表明,3种混凝剂的絮体形成能力由强到弱为PAC-Al30〉PAC-Al13〉AlCl3.与AlCl3相比,PAC-Al13和PAC-Al30的适用pH范围更宽,为5.0-8.0.PAC-Al30和PAC-Al13的电中和能力差别不明显;由于更强的吸附和架桥作用,在低投量下PAC-Al30表现出更好的混凝效果,而且PAC-Al30比AlCl3和PAC-Al13有更宽的有效投量范围,为0.08-0.64 mmol/L.对于腐殖酸含量为10 mg/L的水样,在pH为7.0,投量为0.16 mmol/L下,PAC-Al30对腐殖酸去除率达到98.5%,此时出水残留铝浓度为0.066 mg/L.结果证实Al30是可用于水中腐殖酸去除的一种新型的混凝/絮凝活性成分.Polyaluminum chloride PAC-Al13 with high Al13 content and PAC-Al30 with high Al30 content were prepared. Coagulation behaviors of PAC-Al30, PAC-Al13 and AlCl3 for humic acid removal from water were compared by jar-test. The floc growth, the charge neutralization capacity, the effect of pH and coagulant dosage on coagulation efficiency were investigated, and the residual aluminium in the purified water was considered. The results show that the order of the floc formation capacity is PAC-Al30 〉 PAC-Al13 〉 AlCl3. PAC-Al30 and PAC-Al13 have a broader effective pH range of 5.0-8.0, compared with AlCl3 . The difference of charge neutralization capacity between PAC-Al30 and PAC-Al13 is not significant, but PAC-Al30 performs a more effective coagulation at low coagulant dosages because of its stronger adsorption and bridging, and PAC-Al30 has a broader effective dosage range of 0.08-0.64 mmol/L, compared with AlCl3 and PAC-Al13 . The humic acid removal reaches 98.5% at a pH of 7.0 and a PAC-Al30 dosage of 0.16 mmol/L for the sample water with a humic acid content of 10 mg/L; and the residual aluminum in the purified water is 0.066 mg/L. The results verify that Al30 is another highly efficient coagulation/flocculation species for humic acid removal.

关 键 词：PAC-Al30 PAC-Al13 腐殖酸 残留铝 絮体粒度 Ζ电位 

分 类 号：X703.5[环境科学与工程—环境工程]