Response of nitrogen removal performance and microbial community to a wide range of pH in thermophilic denitrification system. (May 2022)

• Record Type: Journal Article
• Authors: Shi, Shuohui; He, Lei; Zhou, Ying; Fan, Xing; Lin, Ziyuan; He, Xuejie; Zhou, Jian
• Is Part Of: Bioresource technology. Volume 352(2022)
• Publication Date: 2022-05
• Subjects: High temperature -- Nitrogen removal -- Denitrification -- Nitrate respiration -- Microbial community structure; 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.2022.127061
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Thermophilic denitrification showed adaptation to a wide range of pH (5–11). pH 3 inhibited thermophilic denitrification with nitrite and ammonia accumulation. Enriched functional thermophiles contributed to the tolerance to unfavorable pH. The imbalance of incomplete denitrifiers resulted in nitrite accumulation at pH 3. pH 3 facilitated partial denitrification and DNRA at high temperature (50 °C). Abstract: Thermophilic biological nitrogen removal would be a promising alternative to conventional approaches for the treatment of high-temperature wastewater. In this study, the response of thermophilic denitrification system (50 °C) to a wide range of pH (3–11) was investigated. The results showed that thermophilic denitrification could adapt to pH 5–11, but suffered from obvious nitrite and ammonia accumulation at pH 3. Microbial insights indicated that the enrichment of specific functional thermophiles has contributed to the tolerance towards unfavorable pH. Besides, the potential selecting advantage of nitrate reducing bacteria over nitrite reducing bacteria and the enrichment of dissimilatory nitrate reduction to ammonium (DNRA) bacteria could be responsible for the nitrite and ammonia accumulation at pH 3. Moreover, the functional gene prediction denoted higher narG/(nirK + nirS) and nrfA at pH 3, which could facilitate partial denitrification and DNRA. These findings could provide new insight into the application of thermophilic biological nitrogen removal.