Large pilot-scale submerged anaerobic membrane bioreactor for the treatment of municipal wastewater and biogas production at 25 °C

• Published in: Bioresource technology Vol. 319; no. C; p. 124123
• Main Authors: Kong, Zhe, Wu, Jiang, Rong, Chao, Wang, Tianjie, Li, Lu, Luo, Zibin, Ji, Jiayuan, Hanaoka, Taira, Sakemi, Shinichi, Ito, Masami, Kobayashi, Shigeki, Kobayashi, Masumi, Qin, Yu, Li, Yu-You
• Format: Journal Article
• Language: English
• Published: United Kingdom Elsevier Ltd 01-01-2021; Elsevier
• Subjects: Anaerobic digestion; AnMBR; Demonstration, biogas; Mass balance; Municipal wastewater; Mass balance; Demonstration, biogas; Anaerobic digestion; AnMBR; Municipal wastewater
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2020.124123

•5 m3 large-scale AnMBR realized effluent COD < 50 mg L-1 and BOD5 < 10 mg L-1.•COD and BOD5 removal over 90% with biogas recovered by 0.25–0.27 L g−1 removed COD.•An auto-control grille system facilitated AnMBR by removing large-size impurities.•60%-64% of influent COD converted to methane and 20%-26% of that converted to MLSS.•Hollow fiber membrane realized an average flux of 0.35 m d-1 at a △TMP of 23.5 kPa.
The aim of this work was to demonstrate the operation of a large pilot-scale submerged anaerobic membrane bioreactor (5.0 m3) for biogas production from municipal wastewater at ambient temperature of 25 °C. To the best of our knowledge, this is the largest one-stage submerged AnMBR that has ever been reported. This AnMBR realized a hydraulic retention time (HRT) of 6 h and a treatment capacity of 20 m3 d-1, obtaining excellent effluent quality with COD removal efficiency over 90% and BOD5 removal over 95%. The biogas yield of the AnMBR was 0.25–0.27 L g−1 removed COD and 0.09–0.10 L L-1 raw wastewater. The methane content of the biogas was at the range of 75%-81%. The COD and nitrogen mass balance were also identified based on long-term operation. The hollow-fiber membrane module realized a flux of 2.75–17.83 LMH. An online backwash chemical cleaning system helped to lower the transmembrane pressure timely.