摘要
活性污泥法主要依靠不同种群微生物的生物代谢作用降解废水中的有机物,在微生物不断获得能量合成新细胞的过程中将不可避免地产生由蛋白质、多糖、腐殖质和DNA等成分组成的微生物胞外聚合物(EPS)。本研究旨在探究废水生物处理过程中废水氯化消毒副产物的内源性生物源前驱物的来源,对微生物EPS的氯化消毒副产物生成情况进行研究。实验通过GC/MS研究确认了SBR小试反应器中产生的EPS经氯化消毒后生成的副产物种类;同时也对模拟的EPS细胞成分,即分别对蛋白质、多糖、腐殖酸和DNA 4种化合物的氯化消毒副产物种类进行具体考察。研究表明,微生物EPS(包括溶解性EPS和结合性EPS)生成了若干种类的THMs和HAAs类消毒副产物,是废水消毒副产物的生物源前驱物。模拟生化成分预测的消毒副产物种类与SBR反应器中实际的微生物EPS经氯化消毒后的副产物种类基本吻合。
Activated sludge processes mainly rely on microorganism metabolism to treat water and invariably produce extra-cellular polymeric substances（EPS） that mainly contain protein,carbohydrate,humic acids and nucleic acids,therefore the present study is relevant to understand the origin of disinfection byproducts（DBPs） in the process of wastewater disinfection by chlorine.This study represents the first investigation of DBPs species formed by chlorinating the EPS.The chlorination of model compounds（bovine serum albumin,starch,DNA and humic acid）,and actual EPS collected from the sequencing batch reactor（SBR） were both conducted in this study,the main aim of which was to verify the trihalomethanes（THMs） and haloacetic acids（HAAs） species produced from them as precursors upon chlorination.The results showed that the EPS（both exterior soluble EPS and interior bound EPS） do form significant species of THMs and HAAs upon chlorination under the present conditions,and the species predicted from the model chemical compounds showed a good correlation with those obtained from the EPSb and EPSs in the SBR.
基金
高等学校博士学科点专项科研基金资助项目(20090071110005)
国家自然科学基金资助项目(51078091)
