Understanding the impacts of intermittent electro field on the bioelectrochemical aniline degradation system: Performance, microbial community and functional enzyme

• Published in: Environmental research Vol. 231; no. Pt 1; p. 116039
• Main Authors: Wu, Nanping, Zhang, Qian, Tan, Bin, Su, Junhao, Feng, Jiapeng, Zhang, Yunjie, He, Jing, Li, Meng, He, Qi
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 15.08.2023
• Subjects: Aniline wastewater; Electric field mode; Interspecies relationship; Microbial community; Nitrogen removal; Aniline wastewater; Nitrogen removal; Interspecies relationship; Microbial community; Electric field mode
• ISSN: 0013-9351; 1096-0953
• DOI: 10.1016/j.envres.2023.116039

On account of the lack of a sustainable electron donor source and the inhibitory effect of aniline on denitrogenation make it tough to achieve simultaneous removal of aniline and nitrogen. Herein, the strategy of adjusting electric field mode was applied to the electro-enhanced sequential batch reactors (E-SBRs: R1 (continuous ON), R2 (2 h-ON/2 h-OFF), R3 (12 h-ON/12 h-OFF), R4 (in the aerobic phase ON), R5 (in the anoxic phase ON)) to treat aniline wastewater. Aniline removal rate reached approximately 99% in the five systems. Decreasing electrical stimulation interval from 12 to 2 h significantly improved the electron utilization efficiency for aniline degradation and nitrogen metabolism. The total nitrogen removal was achieved from 70.31% to 75.63%. Meanwhile, the hydrogenotrophic denitrifiers of Hydrogenophaga, Thauera, and Rhodospirillales, enriched in reactors of minor electrical stimulation interval. Accordingly, the expression of functional enzyme related to electron transport was incremental with the proper electrical stimulation frequency. [Display omitted] •The minor electrical stimulation interval accelerated aniline degradation.•h-ON/2 h-OFF obtained the optimal TN removal efficiency.•Electric field mode regulated the utilization of EPS to influence electron transport.•Proper electric field mode enriched the abundance of hydrogenotrophic denitrifier.•Suitable modes made the interspecies relationship simpler and more reciprocal.