title: Bioproduction of volatile fatty acid from the fermentation of waste activated sludge for in situ denitritation.
abstract: Waste activated sludge (WAS) fermentation integrated with denitritation (the reduction of nitrite to dinitrogen gas) at different pHs was investigated in batch-mode reactors over a 24-day period. The results showed that in comparison with controlled pHs, the volatile fatty acid (VFA) bioproduction for in situ denitritation was significantly improved at uncontrolled pH. VFA fermented from WAS was quickly consumed by denitritation at uncontrolled pH, which accelerated sludge degradation. On the other hand, sludge digestion was benefited from the alkalinity produced from denitritation, while methanogenesis was prohibited by alkalinity and nitrite. The integrated sludge fermentation and denitritation can be cost-effectively applied to wastewater treatment plants, so that organic substrates (e.g., VFAs) are produced for denitritation via simultaneous sludge fermentation, which enables WAS reutilization and enhances nitrogen removal efficiency without the need of external carbon sources.
authors.affiliation: Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
authors.forename: Bo
authors.initials: B
authors.lastname: Wang
authors.affiliation: Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China. Electronic address: pyz@bjut.edu.cn.
authors.forename: Yongzhen
authors.initials: Y
authors.lastname: Peng
authors.affiliation: Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
authors.forename: Yuanyuan
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Key Laboratory of Beijing for Water Quality Science and Water Environment Recovery Engineering, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
authors.forename: Shuying
authors.initials: S
authors.lastname: Wang
mesh_terms: D019149:Bioreactors; D002244:Carbon / Q000378:metabolism; D005232:Fatty Acids, Volatile / Q000096:biosynthesis*; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D008697:Methane / Q000378:metabolism; D009573:Nitrites / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism*; D012722:Sewage / Q000737:chemistry*
chemical_list: D005232:Fatty Acids, Volatile; D009573:Nitrites; D012722:Sewage; D002244:Carbon; D009584:Nitrogen; D008697:Methane
keywords: Denitritation; Fermentation; Volatile fatty acid; Waste activated sludge; pH