冷融技术联合化学调理对污泥脱水性能的影响及其机理  

The effect and mechanism of freeze/thawing combined with chemical treatment on sludge dewaterability

作　　者：李恺[1] 叶志平[1] 王凤英[1] 李焕文[1] 

机构地区：[1]华南师范大学化学与环境学院,广州510006

出　　处：《环境科学学报》2010年第3期536-543,共8页Acta Scientiae Circumstantiae

摘　　要：实验对比了常温(25℃)下阳离子聚丙烯酰胺(CPAM)、FeCl3/CaO、加酸及阳离子表面活性剂(CTAC)4种处理方式对污泥的调理效果.结果表明,CTAC对污泥的调理效果最好,可使污泥滤饼含水率降至68%.0℃时,未经处理(原泥)、CPAM、FeCl3/CaO、加酸处理条件下污泥脱水效果较常温时都有不同程度的提高,效果最好的为未经处理(原泥)和pH=2条件下的泥样;-15℃时,CTAC条件下滤饼含水率较常温下降了约6%,达到62.8%.污泥胞外聚合物(EPS)含量和污泥絮体结构对污泥脱水性能有一定影响.测定发现,EPS的溶出提高了絮体可压缩性,使污泥絮体内部结合水流出,从而改善污泥的脱水性能.电镜扫描(SEM)和粒径分析结果表明,经过FeCl3/CaO、加酸、CTAC和冷融处理后污泥表面结构和颗粒大小变化明显,脱水效果较原泥均有不同程度的提高.We tested the effect of cationic polyacrylamide（CPAM）,FeC13 /CaO,acid conditioning and cationic surfactant（CTAC,n-hexadecyltrimethylammonium chloride）on sludge at normal temperature（25℃）.CTAC had the best effect,bringing the sludge cake moisture down to 68%.At 0℃,the above test was also done for the following conditions：untreated,CPAM,FeC13/CaO,and acid conditioning.The sludge cake moisture is lower at 0℃ than that at normal temperature.The untreated sludge and pH=2 sludge had the lowest moisture.At-15 ℃,CTAC brought the sludge cake moisture down to 62.8%,6% lower than at normal temperature.The sludge EPS content and floc structure have some influence on sludge dewaterability.Release of EPS can enhance the floc＇s compressibility,forcing the internal water out of the floc,thus improving the sludge dewaterability.By electron microscope scanning and particle size analysis,FeC13/CaO、acid、CTAC and freeze/thawing can all change the floc structure of sludge to improve the dewaterability.

关 键 词：冷融 化学调理 污泥 脱水性能 

分 类 号：X703[环境科学与工程—环境工程]