Aalto University, Department of Built Environment, P.O. Box 15200, FI-00076 AALTO Espoo, Finland.
Aalto University, Department of Built Environment, P.O. Box 15200, FI-00076 AALTO Espoo, Finland.
Sci Total Environ. 2017 Dec 15;605-606:291-299. doi: 10.1016/j.scitotenv.2017.06.191. Epub 2017 Jun 29.
In this study the influence of low-temperature (8°C), sludge retention time (SRT) and loading of spotlight wastewater micropollutants (MPs) on bacterial community of activated sludge was investigated with a special focus on nitrification. Two Sequencing batch reactors (SBR) and two membrane bioreactors (MBR) were operated with synthetic municipal-like wastewater receiving and not receiving ibuprofen, diclofenac, estrone and 17α-ethynylestradiol (EE2). Bacterial population studies were related to removal efficiencies of studied MPs. The results showed that studied bacterial communities significantly differed from all previously published nitrifying activated sludge communities. Exceptionally low concentration of autotrophic nitrifying bacteria were found (<0.5%) as well as no common heterotrophic nitrifies were presenting in activated sludge and therefore could not be related to the MPs removal. Additionally SRT had a spacious effect on the diversity of bacteria and bacterial population shifts under pressure of MPs. Growth of Firmicutes was suppressed by presence of MPs in all the reactors. Increase of MPs concentrations in wastewater improved the removal of EE2. Abundance of Delta- and Gammaproteobacteria showed positive correlation with diclofenac removal.
本研究考察了低温（8°C）、污泥停留时间（SRT）和 spotlight 废水微污染物（MPs）负荷对活性污泥中细菌群落的影响，特别关注硝化作用。使用合成市用水和不接受布洛芬、双氯芬酸、雌酮和 17α-乙炔基雌二醇（EE2）的两个序批式反应器（SBR）和两个膜生物反应器（MBR）进行操作。细菌种群研究与研究 MPs 的去除效率相关。结果表明，研究的细菌群落与所有以前发表的硝化活性污泥群落明显不同。自养硝化细菌的浓度异常低（<0.5%），并且在活性污泥中没有常见的异养硝化菌，因此不能与 MPs 的去除相关。此外，SRT 对细菌的多样性和 MPs 压力下细菌种群的变化有很大的影响。所有反应器中 MPs 的存在都抑制了厚壁菌门的生长。废水中 MPs 浓度的增加提高了 EE2 的去除率。δ-和γ-变形菌门的丰度与双氯芬酸的去除呈正相关。
