混凝剂对超滤膜去除有机物及膜污染的影响  

Effect of Coagulant on Ultrafiltration Membrane for Organic Matter Removal and Membrane Fouling

作　　者：张健[1,2] 殷祺 陈艳 徐鹏成[1,2] 李惠平 ZHANG Jian;YIN Qi;CHEN Yan;XU Pengcheng;LI Huiping(School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Lanzhou 730070,China;Key Laboratory of Yellow River Water Environment in Gansu Province,Lanzhou 730070,China;Wujiang Huayan Water Group,Suzhou 215220,China)

机构地区：[1]兰州交通大学环境与市政工程学院,甘肃兰州730070 [2]甘肃省黄河水环境重点实验室,甘肃兰州730070 [3]吴江华衍水务有限公司,江苏苏州215220

出　　处：《净水技术》2022年第1期51-57,102,共8页Water Purification Technology

基　　金：国家“十三五”重大水专项:苏州市饮用水安全保障技术集成与综合(2017ZX07201001)。

摘　　要：以太湖水为研究对象,采用超滤工艺,通过分别投加混凝剂Al_(2)(SO_(4))_(3)和聚合氯化铝(PAC),分析混凝过程对超滤膜运行效果及压力的影响。结果表明:混凝可以有效提高超滤对有机物的去除效果,Al_(2)(SO_(4))_(3)和PAC投加量大于6 mg/L和3 mg/L(以Al^(3+)计)时,混凝剂对超滤去除有机物的提升效果趋于稳定;混凝可以有效减缓超滤膜膜压差的增长和不可逆污染,单独超滤时不可逆污染指数(HIFI)为0.00292,最佳投加量下Al_(2)(SO_(4))_(3)-UF和PAC-UF的HIFI分别为0.00113和0.00102;造成超滤膜不可逆膜污染的有机物主要以具有紫外响应的中分子量有机物为主,其次是中、小分子量无紫外响应的溶解性有机物(dissolved organic compound,DOC);Al_(2)(SO_(4))_(3)混凝剂更易于减少中等分子量有机物对超滤膜的污染,PAC混凝剂更易于减少小分子量有机物对超滤膜的污染。Take Taihu Lake as research object,adopt ultrafiltration(UF)process to analyze the influence of coagulation process on operation effect and pressure of UF membrane by adding coagulant Al_(2)(SO_(4))_(3)and polymeric aluminum chloride(PAC)respectively.Results showed that coagulation process could effectively improve the effect of ultrafiltration on the removal of organic matter.When the dosage of Al_(2)(SO_(4))_(3)and PAC were greater than 6 mg/L and 3 mg/L(measured by Al^(3+)),the promoting effect of coagulant on the removal of organic matter tends to be stable.Coagulation process could effectively relieve the growth of pressure and irreversible pollution of UF membrane.The HIFI of UF alone was 0.00292,and the HIFI of Al_(2)(SO_(4))_(3)-UF and PAC-UF were 0.00113 and 0.00102,respectively,under the optimal dosage.According to molecular weight distribution,medium molecular weight organics with UV response were the main factors causing irreversible membrane fouling of ultrafiltration membrane,followed by dissolved organics carbon(DOC)with no UV response at medium and small molecular weights.Al_(2)(SO_(4))_(3)coagulant was easier to reduce the foul of UF membrane caused by medium molecular weight organic matter,and PAC coagulant was easier to reduce the foul of UF membrane caused by small molecular weight organic matter.

关 键 词：混凝 超滤 有机物 跨膜压力 分子量分布 

分 类 号：TU991.2[建筑科学—市政工程]