Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan.
Department of Civil and Environmental Engineering, Graduate School of Engineering, Tohoku University, 6-6-06 Aoba, Aramaki, Aoba-ku, Sendai 980-8579, Japan.
Sci Total Environ. 2020 Nov 25;745:140903. doi: 10.1016/j.scitotenv.2020.140903. Epub 2020 Jul 17.
Pore size is one of the most important properties in the successful operation of membrane-based bioprocesses for the treatment of municipal wastewater. The characteristics of two anaerobic membrane bioreactors (AnMBRs), one with a hollow fiber membrane of 0.4 μm pore size (AnMBR1), and the other with a membrane of 0.05 μm pore size (AnMBR2) were investigated for the treatment of real municipal wastewater at room temperature (25 °C) under varied hydraulic retention times (HRTs). Process performance was evaluated in terms of organic removal efficiency, biogas production and membrane filtration behaviours during a long-term continuous operation. Both AnMBRs showed good organic removal performance with COD and BOD removal efficiencies of around 89% and 93%, respectively. High energy recovery potential was achieved, with the biogas yield ranging between 0.20 and 0.26 L-gas/g-COD and a methane content of approximately 75%. The differences in the membrane filtration behaviours in the two AnMBRs included different permeate flux and total filtration resistance (R). In the AnMBR with a 0.4 μm pore size membrane, an average R of 1.08 × 10^12 m was obtained even when the permeate flux was a high 0.274 m/day, while a higher average R of 1.51 × 10^12 m was observed in the AnMBR with 0.05 μm pore size membrane even when the flux was a low 0.148 m/day. The off-line membrane cleaning strategy used for AnMBR1 indicated that the membrane restoration efficiency was 90.2%.
孔径是膜基生物工艺成功运行的最重要特性之一，该工艺用于处理城市污水。本研究考察了两种厌氧膜生物反应器（AnMBR）的特性，一种采用孔径为 0.4μm 的中空纤维膜（AnMBR1），另一种采用孔径为 0.05μm 的膜（AnMBR2），以在室温（25°C）下处理实际城市污水，并采用不同水力停留时间（HRT）。通过长期连续运行，从有机去除效率、沼气产量和膜过滤行为等方面评估了工艺性能。两种 AnMBR 均表现出良好的有机去除性能，COD 和 BOD 去除率分别约为 89%和 93%。实现了高能量回收潜力，沼气产率在 0.20 到 0.26 L-气体/g-COD 之间，甲烷含量约为 75%。两种 AnMBR 的膜过滤行为存在差异，包括不同的渗透通量和总过滤阻力（R）。在孔径为 0.4μm 的 AnMBR 中，即使渗透通量高达 0.274m/天，平均 R 也达到 1.08×10^12 m，而在孔径为 0.05μm 的 AnMBR 中，即使通量较低为 0.148 m/天，仍观察到较高的平均 R 为 1.51×10^12 m。用于 AnMBR1 的离线膜清洗策略表明，膜恢复效率为 90.2%。
