钙离子胁迫下SRT对MBR中污泥性质及膜污染的影响  

Influences of sludge retention time on sludge properties and membrane fouling of submerged membrane bioreactor with the addition of Ca^(2+)

作　　者：肖小兰[1] 陈康[1] 王新华[1] 李秀芬[1] 钱捷婕[1] 

机构地区：[1]江南大学环境与土木工程学院,无锡214122

出　　处：《膜科学与技术》2012年第4期112-117,共6页Membrane Science and Technology

基　　金：江苏省自然科学基金项目(BK2011159);污染控制与资源化研究国家重点实验室开放课题(PCRRF11021);国家自然科学基金(21107035)

摘　　要：以处理模拟生活污水的浸没式膜-生物反应器(SMBR)为依托,在钙离子投加量为200mg/L的条件下,考察了不同污泥龄(10d、20d和30d)对污泥性质以及膜污染的影响.结果表明,随着SRT的延长,TMP的增长速率逐渐降低,膜污染得到了有效缓解,其中SRT为30d时,膜污染最轻.当SRT从10d延长到30d时,SMP的含量明显降低,与膜污染变化趋势是一致的.较长的SRT下钙离子更易于累积,钙离子的累积造成了MLVSS/MLSS值的降低,同时也强化了生物絮凝作用,促进了较大絮体的形成.累积的钙离子主要附着于BEPS中,且通过吸附SMP中带负电荷官能团的多糖,导致了较长SRT下SMP含量的降低和BEPS含量的增加.A submerged membrane bioreactor （SMBR） for treating synthetic wastewater containing 200 mg/L calcium ion was operated under sludge retention time （SRT） of 10 d, 20 d and 30 d in this study in order to verify the impacts of SRT on sludge properties and membrane fouling with the addition of Ca2＋. The results showed that membrane fouling in terms of growth tendency of TMP was effectively controlled with the increase of SRT, and the least membrane fouling rate was achieved at SRT of 30 d. The concentration of soluble microbial products （SMP） significantly decreased as SRT prolonged from 10 d to 30 d, which correlated well with the variation of membrane fouling. The Ca2＋ accumulated in MBR as the SRT extended, and the accumulation of Ca2＋ enhanced bioflocculation and resulted in the decrease of MLVSS/MLSS ratio and the increase of the average particle size. The accumulated Ca2＋ in mixed liquor was mainly located in bound extracellular polymeric substances （BEPS）. And the negatively functional groups such as polysaccharide in SMP were adsorbed to BEPS by the bridging effects of Ca2＋ , which led to the reduction of SMP and increase of BEPS at longer SRT.

关 键 词：膜-生物反应器 污泥龄 钙离子 膜污染 胞外聚合物 

分 类 号：X703[环境科学与工程—环境工程]