Ahmed Zubair, Lim Byung-Ran, Cho Jinwoo, Song Kyung-Guen, Kim Ki-Pal, Ahn Kyu-Hong
Center for Environmental Technology Research, Energy & Environment Research Division, Korea Institute of Science and Technology, Seoul 130-650, Republic of Korea.
Water Res. 2008 Jan;42(1-2):198-210. doi: 10.1016/j.watres.2007.06.062. Epub 2007 Jun 30.
Bacterial community structures in four sequencing anoxic/anaerobic-aerobic membrane bioreactors (SAMs) that were fed with synthetic medium composed of different organic compounds in substrate as carbon source; acetate-dominant (acetate/propionate = 4/1), propionate-dominant (acetate/propionate = 1/4), glucose-dominant (glucose/acetate = 4/1) and methanol-dominant (methanol/acetate/propionate = 6/3/1) were analyzed by respiratory quinone profile and fluorescent in situ hybridization (FISH) techniques. The SAMs were operated at controlled pH range 7-8.5 and at constant temperature 25 degrees C. Total nitrogen (TN), total phosphorus (TP) and COD removal performances were also evaluated and compared. In addition, trans-membrane pressure was monitored to observe the impact of substrate composition on membrane fouling. The dominance of the mole fraction of ubiquinone (UQ-8) in the SAMs indicated dominance of the beta-subclass of Proteobacteria; however, its population comparatively decreased when the substrate was glucose dominant or methanol dominant. A relatively higher and stable enhanced biological phosphorus removal performance was observed when methanol-dominant substrate was used concurrently with an increase in the gamma-subclass of Proteobacteria. The population of the alpha-subclass of Proteobacteria slightly increased along with a decrease in phosphate removal activity when the substrate was glucose-dominant. Results from FISH analysis also supported the findings of the quinone profile. The trans-membrane pressure variation in the SAMs indicated that fouling was relatively rapid when propionate-dominant or methanol-dominant substrate was used and most stable when glucose-dominant substrate was used. A combination of methanol and acetate would be a better choice as an external carbon source when nutrients removals, as well as fouling, are considered in the membrane bioreactor- (MBR-) coupled biological nutrients removing (BNR) process.
对四个序批式缺氧/厌氧-好氧膜生物反应器（SAMs）中的细菌群落结构进行了分析，这些反应器以含有不同有机化合物作为底物碳源的合成培养基为食；乙酸盐为主（乙酸盐/丙酸盐 = 4/1）、丙酸盐为主（乙酸盐/丙酸盐 = 1/4）、葡萄糖为主（葡萄糖/乙酸盐 = 4/1）和甲醇为主（甲醇/乙酸盐/丙酸盐 = 6/3/1），采用呼吸醌谱和荧光原位杂交（FISH）技术。SAMs在pH值7 - 8.5的控制范围内和25℃的恒定温度下运行。还评估并比较了总氮（TN）、总磷（TP）和化学需氧量（COD）的去除性能。此外，监测跨膜压力以观察底物组成对膜污染的影响。SAMs中泛醌（UQ - 8）摩尔分数的优势表明变形菌β亚类占优势；然而，当底物以葡萄糖为主或甲醇为主时，其数量相对减少。当以甲醇为主的底物与变形菌γ亚类的增加同时使用时，观察到相对较高且稳定的强化生物除磷性能。当底物以葡萄糖为主时，变形菌α亚类的数量略有增加，同时磷酸盐去除活性降低。FISH分析结果也支持了醌谱的发现。SAMs中的跨膜压力变化表明，当使用丙酸盐为主或甲醇为主的底物时，污染相对较快，而当使用葡萄糖为主的底物时最稳定。在膜生物反应器（MBR）耦合生物营养物去除（BNR）过程中，考虑营养物去除以及污染时，甲醇和乙酸盐的组合将是更好的外部碳源选择。
