Membrane fouling of submerged membrane bioreactors: impact of mean cell residence time and the contributing factors.
Membrane fouling of submerged membrane bioreactors: impact of mean cell residence time and the contributing factors.
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DOI：
10.1021/es0516155
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发表时间：
2006-03
影响因子：
11.4
通讯作者：
H. Ng;T. W. Tan;S. Ong
中科院分区：
文献类型：
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作者：
H. Ng;T. W. Tan;S. Ong
在本研究中，四个实验规模的预缺氧浸没式膜生物反应器（MBR）在不同的平均细胞停留时间（MCRTs）（3,5,10和20天）同时运行，以系统地阐明膜污染的影响因素。在接下来的5天MCRT mbr中，第一次观察到严重的膜污染。在10天和20天的MCRT mbr中检测到最小的膜污染。微滤膜的污染不受混合液悬浮物浓度和生物质zeta电位的控制。相反，膜污染率随着可溶性微生物产物和细胞外聚合物浓度的增加而增加，两者都随着MCRT的降低而增加。混合液上清液的总有机碳、蛋白质、碳水化合物和UV254吸光度随MCRT的降低而增加，且始终高于出水。随着MCRT的增加，混合液上清中碳水化合物的积累而不是蛋白质的积累减少。归一化的毛细吸力时间值而不是毛细吸力时间值将指示混合液的膜污染电位。利用扫描电镜和激光共聚焦扫描显微镜对污染膜进行图像分析，发现生物膜的形成是导致膜污染的原因。
In this study, four bench-scale pre-anoxic submerged membrane bioreactors (MBR) were operated simultaneously at different mean cell residence times (MCRTs) (3, 5, 10, and 20 days) to systematically elucidate the contributing factors of membrane fouling. Severe membrane fouling was first observed in the 3-day followed by the 5-day MCRT MBRs. Minimal membrane fouling was detected in the 10 and 20-day MCRT MBRs. The fouling of microfiltration membrane was not controlled by mixed liquor suspended solids concentration or zeta potential of biomass. Instead, membrane fouling rate increased with increasing soluble microbial products and extracellular polymeric substances concentrations, which both increased with decreasing MCRT. Total organic carbon, protein, carbohydrate, and UV254 absorbance in the mixed liquor supernatant increased with decreasing MCRT and were consistently higher than those of the effluent. Accumulation of carbohydrates rather than proteins in the mixed liquor supernatant was found to decrease with increasing MCRT. Normalized capilliary suction time value rather than the capilliary suction time value would indicate membrane fouling potential of a mixed liquor. Image analysis of the fouled membrane using scanning electron microscope and confocal laser scanning microscope showed that biofilm formation was the cause of membrane fouling.