再絮凝预处理对超滤膜的污染控制研究  

Study on ultrafiltration membrane fouling control by reflocculation pretreatment

作　　者：陶辉[1,2] 王伦[1,2] 陈卫[1,2] 陈连生[1,2] 

机构地区：[1]河海大学环境学院,江苏南京210098 [2]河海大学浅水湖泊综合治理与资源开发教育部重点实验室,江苏南京210098

出　　处：《华中科技大学学报（自然科学版）》2015年第6期128-132,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家水体污染控制与治理科技重大专项资助项目(2011ZX07410-001);江苏省高校优势学科建设工程资助项目

摘　　要：试验针对混凝-沉淀-再絮凝-超滤组合工艺对水中有机物的强化去除效果和膜污染的控制效能展开研究.结果表明:再絮凝-超滤组合工艺对有机物的单元去除率可达26%,远高于传统的超滤膜组合工艺;同时,该工艺对有机物的去除主要体现在对中性亲水性有机物和分子量分别大于10kDa和小于1kDa的有机物方面,与传统超滤膜工艺有较大区别.当采用硫酸铝作为再絮凝剂,其投加量达到6.0mg/L时,统一膜污染指数(UMFI)达到最小(0.061 3m2/L),表明再絮凝预处理工艺能够更为有效地控制超滤膜的污染.Zeta电位的测试结果表明:再絮凝过程可使沉后水中残余的胶体Zeta电位降至0,从而减轻了膜表面对污染物的吸附;而再絮凝过程中微小絮体的形成也使得沉后水中颗粒物粒径增大,防止了膜孔堵塞现象的发生并使得形成的滤饼层结构较为松散,从而取得良好的超滤膜污染控制效果.To enhance organics removal and membrane fouling control,the comprehensive technology composed by flocculation-sedimentation-reflocculation-ultrafiltration was proposed and tested.Experimental results show that the organics removal achieve 26% in reflocculation-ultrafiltration process which is much higher than that in traditional ultrafiltration technologies.In addition,the removed organics in this process is mainly neutral hydrophilics and the proportions with molecular weights〈1kDa and 〉10 kDa,which is different with that in traditional ultrafiltration process.By using Al2（SO4）3as re-flocculant（6.0mg/L）,the uniform membrane fouling index（UMFI）reaches its minimum at 0.061 3 m2/L which indicates that the reflocculation pretreatment effectively control membrane fouling.The Zeta potential of colloids remaining in sedimentation outlet is reduced to 0in the reflocculation process which lower the adsorption of fouling materials to membrane surface.The flocs formed in reflocculation process enlarge the particulates diameter which induces looser membrane fouling layer formation and gets a good result in ultrafiltration membrane fouling control.

关 键 词：饮用水 超滤 膜污染 再絮凝 有机物 

分 类 号：TU991.1[建筑科学—市政工程]