Enhancing methane production of anaerobic sludge digestion by microaeration: Enzyme activity stimulation, semi-continuous reactor validation and microbial community analysis. (October 2019)

• Record Type: Journal Article
• Authors: Ruan, Danian; Zhou, Zhen; Pang, Hongjian; Yao, Jie; Chen, Guang; Qiu, Zhan
• Is Part Of: Bioresource technology. Volume 289(2019)
• Publication Date: 2019-10
• Subjects: Micro-aeration pretreatment -- Anaerobic digestion -- Methane yield -- Enzyme activity -- 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.2019.121643
• Languages: English
• ISSNs: 0960-8524

Abstract

Graphical abstract: Highlights: Microaeration pretreatment released organic matters and stimulated enzyme activity. CH4 production was significantly correlated with enzyme activity after microaeration. Microaeration increased biogas production by 16.4% and improved sludge dewaterability. Microaeration enriched hydrolytic and fermentative bacteria for anaerobic digestion. Abstract: Effects of microaeration pretreatment on sludge hydrolysis, biogas production and microbial community structure in anaerobic digestion (AD) were investigated by bench-scale tests and semi-continuous experiments. Bench tests showed that microaeration led to the release of dissolved organic matters, generation of volatile fatty acids and stimulation of enzyme activity. Correlation analysis showed that methane production was significantly correlated with the activity of α-glucosidase at 0.01 level, and with protease activity, released polysaccharides and VFAs at 0.05 level. Semi-continuous experiments showed that microaeration accelerated the utilization of organic matters, increased biogas production by 16.4%, enhanced methane content in biogas, and improved sludge dewaterability. Microbial community structure analysis showed that microaeration promoted enrichment of hydrolytic and fermentative bacteria in AD reactor rather than methanogenic bacteria, and aceticlastic methanogenesis was the main methanogenic pathway for methane production.