EPS对细菌凝聚和絮状污泥颗粒化的作用  

Research on the effect of EPS on bacterial coagulation and granulation of flocculated sludge

作　　者：王景华 袁林江 贺向峰 夏大朋 陈雪娇 郑源 WANG Jing-hua;YUAN Linjiang;HE Xiang-feng;XIA Da-peng;CHEN Xue-jiao;ZHENG Yuan(Key Laboratory of Northwest Water Resources and Environmental Ecology,Ministry of Education,Key Laboratory of Enviromental Egineering of Shaanxi Province,School of Enviromental and Municipal Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]西安建筑科技大学环境与市政工程学院,陕西省环境工程重点实验室,西北水资源与环境生态教育部重点实验室,陕西西安710055

出　　处：《中国环境科学》2024年第9期4893-4900,共8页China Environmental Science

基　　金：国家自然科学基金资助项目(51878538)。

摘　　要：为探究胞外聚合物对细菌聚集和絮状污泥凝聚,颗粒化的影响,本文通过向细菌悬浊液中投加LB-EPS与TB-EPS观察细菌凝聚情况;通过向反应器中投加细菌EPS(1号反应器)与不投加细菌EPS反应器(2号反应器)进行对比,考察了两个反应器内污泥的生长变化情况;还利用模拟EPS与真实EPS分别对高岭土混合溶液与细菌菌悬液进行聚集沉淀效率交叉实验.结果显示,LB-EPS对细菌的聚集效率均大于TB-EPS;1号反应器污泥生长迅速并颗粒化,第70d污泥D_(50)达到377.5μm,最大粒径可以达到1.4~1.5mm.第90~100d由于污泥有机负荷不足,EPS浓度下降,颗粒污泥迅速解体,污泥粒径迅速下降,D_(50)由296.5μm迅速下降至109.6μm.而2号反应器污泥粒径在第70d增大到239.5μm(D_(50)),且后续仍在上升;模拟EPS对高岭土的絮凝能力更显著,而EPS对菌悬液中细菌的聚集效果更显著.研究认为胞外聚合物对细菌具有粘附作用,并促进细菌聚集,且LB-EPS较TB-EPS作用大,EPS的加入能够促进污泥颗粒化进程加快;细菌在污泥颗粒化过程中LB-EPS对游离细菌吸附聚集作用大于TB-EPS.In order to explore the influence of extracellular polymers substances on bacterial aggregation and flocculent sludge agglomeration and granulation,bacterial aggregation by adding LB-EPS and TB-EPS to the bacterial suspension was observed.By adding bacteria EPS to the reactor (No.1) or not (No.2),the growth changes of aerobic granular sludge in the two reactors were investigated.The aggregation and precipitation efficiency of kaolin mixed solution and bacterial suspension was carried out by simulated EPS and real EPS respectively.The results showed that the aggregation efficiency of LB-EPS for bacteria was higher than that of TB-EPS in both groups of reactors.The sludge in reactor No.1 grew rapidly and granulated.On the 70th day,the D_(50) of the sludge reached 377.5μm,and the maximum particle size could reach 1.4~1.5mm.From day 90 to day 100,due to insufficient organic load of sludge,the EPS concentration decreased,the granular sludge disorganized rapidly,and the sludge particle size decreased rapidly,and the D_(50) decreased rapidly from 296.5μm to 109.6μm.The particle size of sludge in reactor No.2 increased to 239.5μm(D_(50)) on day 70,and continued to rise thereafter.The simulated EPS had more significant flocculation ability for kaolin,and the EPS had more significant effect on the aggregation of bacteria in bacterial suspension.It was concluded that extracellular polymers had adhesion effect on bacteria and promoted bacterial aggregation,and the adhesion effect of LB-EPS on bacteria was greater than that of TB-EPS.The addition of EPS could accelerate the granulation process of sludge.In the process of sludge granulation,the adsorption and aggregation effect of LB-EPS on free bacteria was greater than that of TB-EPS.

关 键 词：胞外聚合物 好氧颗粒污泥 细菌聚集 

分 类 号：X172[环境科学与工程—环境科学]