铁离子对膜生物反应器中污泥性质及膜污染的影响  

Effects of iron ion on the sludge properties and membrane fouling in the submerged membrane bioreactors

作　　者：钱捷婕[1] 王新华[1] 李秀芬[1] 华兆哲[1] 谈玉琴 

机构地区：[1]江南大学环境与土木工程学院环境生物技术研究室,江苏无锡214122 [2]无锡金鑫集团有限公司,江苏无锡214122

出　　处：《安全与环境学报》2011年第4期68-72,共5页Journal of Safety and Environment

基　　金：国家自然科学基金项目(50678073);江苏省科技支撑计划-社会发展项目(BE2009636)

摘　　要：以处理模拟生活污水的平板膜-生物反应器为依托,将进水铁离子质量浓度分别调配成6 mg/L、18 mg/L、40 mg/L,考察三价铁离子对膜生物反应器中污泥性质及膜污染的影响。结果表明,投加铁离子对平板膜-生物反应器的出水水质影响不大。随着铁离子投加质量浓度的增加,跨膜压差(TMP)增长趋势变小,膜污染得到缓解,其中铁离子投加质量浓度为40 mg/L时,膜污染控制效果最好。铁离子的投加强化了生物絮凝作用,造成污泥质量浓度的上升,溶解性微生物产物(SMP)和松散型胞外聚合物(LB-EPS)质量比的下降。从膜阻力分析可以看出,投加铁离子主要是降低SMP和LB-EPS等凝胶层污染物引起的外部阻力。In this study, we have investigated the effect of the iron ion on the sludge properties and membrane fouling in a flat sheet membrane bioreactor （MBR） by changing the iron ion concentration in the influent water to 6 mg/L, 18 mg/L and 40 mg/L. The results of our experiments show that the iron ion had little effect on the effluent water quality of the MBR, and the effluent chemical oxygen demand （COD）, ammonia （NH4＋ - N）, total nitrogen （TN） and total phosphorus （TP） were below 22 mg/L, about 5 mg/L, （25.11±2.35） mg/L and （30.04±2.35） mg/L, respectively. The membrane fouling in terms of growth tendency of trans-membrane pressure （TMP） tends to decrease with the increase of iron concentration, and the best permeabihty can be achieved at the iron concentration of 40 mg/L. The increase of iron ion helps to increase the mixed liquor suspended solids （MLSS） but decrease the ratio of mixed liquor volatile suspended solids （MLVSS） to MLSS. In addition, the concentrations of soluble microbial products （SMP） and loosely bounded extracellular polymeric substances （LB- EPS） tend to decrease with the increase of iron ion concentrations caused by the enhanced bioflocculation. However, when the iron ion concentration increased to 40 mg/L, the average particle size would drop to 104 tLm, which can be attributed to the facts that the addition of iron ion can not only increase the size of sludge flocs by enhancing the bioflocculation, but also decrease the average size of the sludge due to the production of inorganic precipitate with smaller size. From the distributions of the membrane resistance, the decrease of membrane resistance by adding ion can mainly be attributed to the decline of the external resistance, which proves to be significantly influenced by the SMP and LB - EPS.

关 键 词：环境工程学 膜-生物反应器 膜污染 铁离子 胞外聚合物 溶解性微生物产物 

分 类 号：TQ028[化学工程]