Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, Guangdong, China; Research Institute of Environmental Engineering & Nano-Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China; Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China.
Research Institute of Environmental Engineering & Nano-Technology, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China; Guangdong Provincial Engineering Research Center for Urban Water Recycling and Environmental Safety, Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, Guangdong, China; School of Environment, Tsinghua University, Beijing 100084, China.
Sci Total Environ. 2019 Feb 20;652:788-799. doi: 10.1016/j.scitotenv.2018.10.284. Epub 2018 Oct 22.
The comparison of long-term ceramic membrane bioreactors (MBRs) without and with in-situ ozonation was investigated in this study in terms of membrane fouling, activated sludge, effluent quality and microbial community in wastewater treatment. The optimal dosage of in-situ ozonation for long-term MBR operation was firstly determined as 5 mg/L (0.66 mg-ozone/g-mixed liquor suspended solid (MLSS)) with the optimal filterability of mixed liquor. During the long-term filtration experiment, MBR-ozone with in-situ ozonation demonstrated its significantly alleviated ceramic membrane fouling performance compared with MBR-control without in-situ ozonation as a result of the enhanced filterability of mixed liquor and organic foulants removal from membrane surface by in-situ ozonation oxidation. Furthermore, ozonation was beneficial to phosphorus removal and the total phosphorus (TP) concentration in effluent of MBR-control (0.82 ± 0.63 mg/L) was >2-fold higher than that of MBR-ozone (0.29 ± 0.41 mg/L). The improved phosphorus removal performance by ozonation was due to the increased abundance of phosphate accumulating bacteria of Candidatus Accumulibacter in activated sludge. However, ozonation was detrimental to nitrogen removal mainly as a result of the inhibition of denitrification with the decreased relative abundance of denitrification genus of Dechloromonas in activated sludge. Overall, ceramic MBR with in-situ ozonation had not only significantly alleviated membrane fouling but also remarkably improved phosphorus removal performance.
本研究比较了长期陶瓷膜生物反应器（MBR）有无原位臭氧氧化在膜污染、活性污泥、出水水质和废水处理中微生物群落方面的差异。首先确定了原位臭氧氧化的最佳剂量为 5mg/L（0.66mg-臭氧/克混合液悬浮固体（MLSS）），此时混合液的过滤性能最佳。在长期过滤实验中，与无原位臭氧氧化的 MBR 相比，具有原位臭氧氧化的 MBR-ozone 表现出明显减轻的陶瓷膜污染性能，这是由于混合液过滤性能的提高和原位臭氧氧化氧化对膜表面有机污染物的去除。此外，臭氧氧化有利于磷的去除，MBR 对照组（0.82±0.63mg/L）的出水中总磷（TP）浓度是 MBR-ozone（0.29±0.41mg/L）的两倍多。臭氧氧化提高磷去除性能的原因是活性污泥中聚磷菌 Candidatus Accumulibacter 的丰度增加。然而，臭氧氧化对氮去除不利，主要是由于活性污泥中反硝化属 Dechloromonas 的相对丰度下降导致反硝化受到抑制。总的来说，具有原位臭氧氧化的陶瓷 MBR 不仅显著减轻了膜污染，而且显著提高了磷去除性能。
