Microbiological mechanism of the improved nitrogen and phosphorus removal by embedding microbial fuel cell in Anaerobic–Anoxic–Oxic wastewater treatment process

• Published in: Bioresource technology 2016-05, Vol.207, p.109-117
• Main Authors: Xie, Beizhen, Liu, Bojie, Yi, Yue, Yang, Lige, Liang, Dawei, Zhu, Ying, Liu, Hong
• Format: Article
• Language: English
• Subjects: AA/O; Bioelectric Energy Sources - microbiology; Biofilms; Bioreactors; Denitrification; DGGE; DNA - chemistry; Electricity; Electrodes; Hypoxia; Illumina Miseq; Microbial fuel cell; Microscopy, Electron, Scanning; Nitrogen - chemistry; Phosphorus - chemistry; Phylogeny; Polymerase Chain Reaction; Rheinheimera; RNA, Ribosomal, 16S - genetics; Sequence Analysis, DNA; Thauera; Thauera - metabolism; Waste Water; Water Pollutants, Chemical - chemistry; Water Purification
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2016.01.090

•The microbial community of AA/O bioreactor was changed by the embedment of MFC.•Thauera and Emticicia were enriched in the suspension of MFC-AA/O bioreactor.•Rheinheimera might contribute to both TN removal enhancement and power generation. Anaerobic–Anoxic–Oxic (AA/O) wastewater treatment process is a widely used wastewater treatment process for simultaneous nitrogen and phosphorus removal. Microbial fuel cell (MFC) can generate electricity and treat the organic wastewater simultaneously. Our previous research showed that embedding MFC in AA/O wastewater treatment process could enhance the pollutants removal efficiency. However, the mechanism was not clear. In this study, a lab-scale corridor-style AA/O reactor with MFC embedded was operated and both the total nitrogen and total phosphorus removal efficiencies were enhanced. DGGE and Illumina Miseq results demonstrated that both the microbial community structures on the surface of the cathode and in the suspensions of cathode chamber have been changed. The percentage of Thauera and Emticicia, identified as denitrifying bacteria, increased significantly in the suspension liquid when the MFC was embedded in the AA/O reactor. Moreover, the genus Rheinheimera were significantly enriched on the cathode surface, which might contribute to both the nitrogen removal enhancement and electricity generation.