Enhanced thermophilic denitrification performance and potential microbial mechanism in denitrifying granular sludge system. (January 2022)

• Record Type: Journal Article
• Authors: Shi, Shuohui; Lin, Ziyuan; Zhou, Jiong; Fan, Xing; Huang, Yangyang; Zhou, Jian
• Is Part Of: Bioresource technology. Volume 344:Part A(2022)
• Publication Date: 2022-01
• Subjects: High temperature -- Nitrogen removal -- Microbial community structure -- Denitrification -- Sequencing batch reactor; 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.2021.126190
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: High temperature (50 ℃) facilitated the formation of denitrifying granular sludge. Thermophilic denitrification showed higher nitrate removal rate. Dominant denitrifying functional bacteria varied with different temperatures. Enriched thermophiles dominated in the thermophilic denitrifying system. The potential microbial mechanism relies on the modulation of metabolism pathways. Abstract: Thermophilic biological nitrogen removal will provide low-cost strategies for the treatment of high-temperature nitrogenous wastewater (greater than 45 ℃). In this study, a thermophilic denitrifying granular sludge system was established at 50 ℃ and compared with mesophilic systems (30 ℃ and 40 ℃). The results showed a significant increase in COD and nitrate removal rate with the elevating temperature. Besides, the microbial community analysis indicated an obvious succession of key functional bacteria at different temperatures. Enriched thermophiles including Truepera, Azoarcus, and Elioraea were the dominant denitrifiers in the thermophilic denitrifying granular sludge system, which ensured the high nitrate removal at 50 ℃. Moreover, the functional gene prediction also denoted an enrichment of nitrate reduction genes and carbon metabolism pathways at 50 ℃, which could explain the enhancement of thermophilic denitrification. These findings could provide new insight into the application of denitrifying granular sludge in thermophilic wastewater treatment.