Two-stage MBR consisting of anaerobic and aerobic reactors was operated at total hydraulic retention time (HRT) of 48 h for the treatment of livestock wastewater containing antibiotics, i.e. amoxicillin (AMX), tiamulin (TIA), and chlortetracycline (CTC), under the (1st) absence and (2nd) presence of sludge recirculation between the reactors. During the operation with sludge recirculation, the removals of organic and nitrogen were enhanced. Meanwhile, the removals of TIA and CTC were found to decrease by 9% and 20% in the aerobic reactor but increased by 5% to 7% in the anaerobic reactor due to the relocation of biomass from the aerobic to the anaerobic reactor. A high degree of AMX biodegradation under both anaerobic and aerobic conditions and partial biodegradation of TIA and CTC under aerobic conditions were confirmed in batch experiments. Moreover, the effect of sludge recirculation on biomass and pollutant removal efficiencies in the 2-stage MBR was revealed using microbial community analyses. Membrane filtration also helped to retain the adsorbed antibiotics associated with small colloidal particles in the system.

由厌氧和好氧反应器组成的两级 MBR 在 48 h 的总水力停留时间 (HRT) 下运行，用于处理含有抗生素的牲畜废水，即阿莫西林 (AMX)、泰妙菌素 (TIA) 和金霉素 (CTC)，在(1) 不存在和 (2) 存在反应器之间的污泥再循环。在污泥循环运行过程中，有机物和氮的去除得到了加强。同时，发现 TIA 和 CTC 的去除在好氧反应器中减少了 9% 和 20%，但在厌氧反应器中增加了 5% 到 7%，这是由于生物质从好氧反应器转移到厌氧反应器。在分批实验中证实了在厌氧和好氧条件下 AMX 的高度生物降解以及有氧条件下 TIA 和 CTC 的部分生物降解。此外，使用微生物群落分析揭示了污泥再循环对 2 阶段 MBR 中生物量和污染物去除效率的影响。膜过滤还有助于保留系统中与小胶体颗粒相关的吸附抗生素。