Lee Woo-Nyoung, Kang In-Joong, Lee Chung-Hak
School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, South Korea.
Water Res. 2006 May;40(9):1827-35. doi: 10.1016/j.watres.2006.03.007.
Factors affecting filtration characteristics in submerged hollow fiber membrane were investigated in membrane-coupled moving bed biofilm reactor (M-CMBBR). The trend of membrane biofouling in M-CMBBR was quite different from that in a conventional membrane bioreactor (MBR). The M-CMBBR showed much lower biofouling rate than a conventional MBR. Whereas the membrane biofouling in conventional MBR system is known to be dependent mostly on biochemical effects of mixed liquor (soluble COD, EPS, etc.), the extent of biofouling in M-CMBBR was largely dependent on the potential collision energy of biofilm carriers (media) moving freely and colliding with surfaces of submerged hollow fibers. The collisions between circulating media and hollow fiber membranes gave rise to frictional forces which mitigated the formation of biofilms on the outer surface of hollow fibers. Consequently, the membrane permeability was greatly enhanced. The potential collision energy of moving media was dependent on the media volume fraction as well as the air flow rate. The membrane permeability was found to be proportional to the relative potential collision energy of the biofilm carriers. The frictional effect on the morphology of biofilms formed on the surface of organic membrane under various operating condition was also examined and identified through their visualization with SEM and AFM.
在膜耦合移动床生物膜反应器（M-CMBBR）中研究了影响浸没式中空纤维膜过滤特性的因素。M-CMBBR中膜生物污染的趋势与传统膜生物反应器（MBR）中的截然不同。M-CMBBR的生物污染速率比传统MBR低得多。虽然已知传统MBR系统中的膜生物污染主要取决于混合液的生化作用（可溶性化学需氧量、胞外聚合物等），但M-CMBBR中的生物污染程度在很大程度上取决于生物膜载体（介质）自由移动并与浸没式中空纤维表面碰撞的潜在碰撞能量。循环介质与中空纤维膜之间的碰撞产生了摩擦力，减轻了中空纤维外表面生物膜的形成。因此，膜的渗透性大大提高。移动介质的潜在碰撞能量取决于介质体积分数以及空气流速。发现膜的渗透性与生物膜载体的相对潜在碰撞能量成正比。还通过扫描电子显微镜（SEM）和原子力显微镜（AFM）对其进行可视化，研究并确定了在各种操作条件下有机膜表面形成的生物膜形态的摩擦效应。
