不同pH值下胞外聚合物对污泥脱水性能及束缚水含量的影响  

Influence of extracellular polymeric substances on sludge dewaterability and bound water content at various pH values

作　　者：邢奕[1] 王志强[1] 洪晨[1] 司艳晓[1] 张坤[1] 刘敏[1] 田星强 李洋[1] 

机构地区：[1]北京科技大学土木与环境工程学院,北京100083

出　　处：《工程科学学报》2015年第10期1387-1395,共9页Chinese Journal of Engineering

基　　金：国家自然科学基金项目(51104009);北京市科技新星计划项目(Z111106054511043);北京市优秀人才培养资助项目(2012D009006000003);中央高校基本科研业务费资助项目(FRF-TP-12-011 B);昆明市科技计划项目(2012-02-09-A-G-02-0001);广东省教育部产学研结合项目(2011B090400629)

摘　　要：研究了不同pH值下污泥脱水性能和束缚水含量的变化,通过测定污泥调理过程中各层胞外聚合物(S-EPS、LB-EPS和TB-EPS)中蛋白质和多糖的含量、S-EPS中有机官能团以及有机酸的含量,探讨了胞外聚合物对污泥脱水性能及束缚水含量的影响.酸性条件下,污泥的脱水性能明显好于中性条件,并且p H值为3.03时,污泥滤饼含水率(WC)和毛细吸水时间(CST)均降至最低,分别为60.8%和25.4 s;碱性条件下,污泥中束缚水的含量明显增加,WC和CST均大幅升高,污泥脱水性能恶化.酸碱的加入导致污泥中TB-EPS含量降低,LB-EPS和S-EPS含量升高,并且EPS各层组均与WC、CST以及束缚水含量具有很强的相关性,其中S-EPS与污泥脱水性能以及束缚水含量的相关性最显著.酸碱调理过程中,部分EPS水解生成有机酸等小分子有机物,S-EPS中有机官能团的总量和种类都有明显增多.The changes of sludge dewaterability and bound water content at various p H values were investigated in this study. The protein and polysaccharide contents in each layer of extracellular polymeric substances（ S-EPS、LB-EPS and TB-EPS） and the organic acid and organic functional group contents in S-EPS were determined in an attempt to explain the influence of EPS on the sludge dewaterability and bound water content. The results indicate that the sludge dewaterability under acidic conditions is obviously better than that under neutral conditions,and the water content of dewatered sludge（ WC） and the capillary suction time（ CST） can be decreased to 60. 8% and 25. 4 s at p H 3. 03,respectively. Under alkaline conditions,the bound water content in dewatered sludge,the WC and CST significantly increase,and the sludge dewaterability deteriorates. The addition of acid or alkali reduces TB-EPS,on the contrary,increases LB-EPS and S-EPS. Each layer of extracellular polymeric substances has significant correlation with the WC,CST and the bound water content,and S-EPS has most significant correlation with the sludge dewaterability and bound water content. In the process of acid-alkali conditioning,the amount and type of organic-functional groups improve obviously and hydrolysis of partly EPS generates organic acids and other small molecules.

关 键 词：污泥处理 调理 胞外聚合物 脱水性能 束缚水 

分 类 号：X705[环境科学与工程—环境工程]