Study on the advanced nitrogen removal under low temperature by biofilm on weak magnetic carriers. (September 2022)

• Record Type: Journal Article
• Authors: Chen, Sien; Yang, Dongli; Wang, Qingxin; Huang, Xueying; Ren, Hongqiang; Xu, Ke
• Is Part Of: Bioresource technology. Volume 360(2022)
• Publication Date: 2022-09
• Subjects: Weak magnetic carrier -- Advanced nitrogen removal -- Low temperature -- Enzyme activity -- Electron transport chain -- Microbial community; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2022.127580
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Weak magnetic carrier enhanced denitrification under low temperature. Weak magnetic carrier inhibited toxic NO2 – accumulation. The "window" effect and different TN degradation pathways were revealed. Activities of substances in electron transport chain were significantly enhanced. Weak magnetic carrier shifted the microbial community and gene expression. Abstract: The advanced nitrogen removal under low temperature is inhibited because of reduction of the microbial activity. Packed bed reactors filled with different magnetic carriers (0, 0.3, 0.6, 0.9 mT) were constructed to enhance advanced denitrification under low temperature (5 ℃). Results showed that 0.3 and 0.9 mT carriers significantly improved denitrification, indicating the "window" effect. Total nitrogen removals were increased by 6.96% and 8.25%, and NO2 – accumulation decreased by 25.70% and 13.90% in 0.3 and 0.9 mT reactors, respectively. Analysis of enzyme activity and electron transport chain showed that 0.3 mT carrier mainly increased NIR activity by improving compound III and cytC abundance while 0.9 mT carrier mainly increased NAR activity by improving compound I and NADH abundance, indicating different pathways. Similar microbial community in 0.3 and 0.9 mT reactors were revealed. Overall, weak magnetic carriers can be used to enhance advanced nitrogen removal under low temperature.