Response of process performance and microbial community to ammonia stress in series batch experiments. (October 2020)

• Record Type: Journal Article
• Authors: Zhang, Hong; Peng, Yun; Yang, Pingjin; Wang, Xiaoming; Peng, Xuya; Li, Lei
• Is Part Of: Bioresource technology. Volume 314(2020)
• Publication Date: 2020-10
• Subjects: Food waste -- Anaerobic digestion -- Ammonia stress -- Microbial community -- Instability mechanism; 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.2020.123768
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: The shift of dominant archaea restored acetate metabolism. LCVFA metabolism was the key link responsible for process instability. Inhibited SAB, not feedback inhibition of HM, hindered LCVFA metabolism. SAB were the key microorganisms responsible for process instability. The inhibition of SAB originated from TAN, and not from FAN. Abstract: To further clarify the key stage and microorganisms responsible for ammonia inhibition instability, three sequential batch experiments were conducted with various ammonia concentrations and different exposure modes. Acetate metabolism was most sensitive to ammonia, however, after continuous ammonia exposure, acetate metabolism was well restored by a shift in dominant microorganisms. In contrast, the metabolism of longer-chain volatile fatty acids (LCVFAs, C3 –C5 ) was only inhibited under a high ammonia concentration (≥6000 mg/L), however, once inhibited, continuous exposure neither restored the abundance of functional microbes nor induced new microorganisms to perform metabolic functions. Therefore, LCVFA metabolism was the key stage responsible for process instability under ammonia stress. Moreover, the deterioration of LCVFA metabolism was caused by the inhibition of syntrophic acetogenic bacteria (SAB) induced by total ammonia nitrogen, rather than the feedback inhibition from methanogenesis. That is, SAB were the key microorganisms involved in process instability.