title: Free sulfurous acid (FSA) inhibition of biological thiosulfate reduction (BTR) in the sulfur cycle-driven wastewater treatment process.
abstract: A sulfur cycle-based bioprocess for co-treatment of wet flue gas desulfurization (WFGD) wastes with freshwater sewage has been developed. In this process the removal of organic carbon is mainly associated with biological sulfate or sulfite reduction. Thiosulfate is a major intermediate during biological sulfate/sulfite reduction, and its reduction to sulfide is the rate-limiting step. In this study, the impacts of saline sulfite (the ionized form: HSO3-+ SO32-) and free sulfurous acid (FSA, the unionized form: H2SO3) sourced from WGFD wastes on the biological thiosulfate reduction (BTR) activities were thoroughly investigated. The BTR activity and sulfate/sulfite-reducing bacteria (SRB) populations in the thiosulfate-reducing up-flow anaerobic sludge bed (UASB) reactor decreased when the FSA was added to the UASB influent. Batch experiment results confirmed that FSA, instead of saline sulfite, was the true inhibitor of BTR. And BTR activities dropped by 50% as the FSA concentrations were increased from 8.0 × 10-8to 2.0 × 10-4mg H2SO3-S/L. From an engineering perspective, the findings of this study provide some hints on how to ensure effective thiosulfate accumulation in biological sulfate/sulfite reduction for the subsequent denitrification/denitritation. Such manipulation would result in higher nitrogen removal rates in this co-treatment process of WFGD wastes with municipal sewage.
authors.affiliation: Department of Applied Chemistry, School of Natural and Applied Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China; State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, China; Research Center for Ecology and Environmental Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China. Electronic address: qianjin131@yahoo.com.hk.
authors.forename: Jin
authors.initials: J
authors.lastname: Qian
authors.affiliation: Department of Applied Chemistry, School of Natural and Applied Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China.
authors.forename: Lianlian
authors.initials: L
authors.lastname: Wang
authors.affiliation: Department of Applied Chemistry, School of Natural and Applied Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China.
authors.forename: Yaoguo
authors.initials: Y
authors.lastname: Wu
authors.affiliation: Advanced Water Management Centre (AWMC), The University of Queensland, QLD 4072, Brisbane, Australia.
authors.forename: Philip L
authors.initials: PL
authors.lastname: Bond
authors.affiliation: Department of Applied Chemistry, School of Natural and Applied Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China.
authors.forename: Yuhan
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Applied Chemistry, School of Natural and Applied Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China.
authors.forename: Xing
authors.initials: X
authors.lastname: Chang
authors.affiliation: Department of Applied Chemistry, School of Natural and Applied Sciences, Northwestern Polytechnical University, NO. 127 West Youyi Road, Xi'an 710072, China.
authors.forename: Baixue
authors.initials: B
authors.lastname: Deng
authors.affiliation: State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
authors.forename: Li
authors.initials: L
authors.lastname: Wei
authors.affiliation: Griffith School of Engineering, Griffith University, Nathan Campus, QLD 4111, Australia; Queensland Miro- and Nanotechnology Centre, Griffith University, Nathan, QLD 4111, Australia.
authors.forename: Qin
authors.initials: Q
authors.lastname: Li
authors.affiliation: Griffith School of Engineering, Griffith University, Nathan Campus, QLD 4111, Australia; Advanced Water Management Centre (AWMC), The University of Queensland, QLD 4072, Brisbane, Australia. Electronic address: qilin.wang@griffith.edu.au.
authors.forename: Qilin
authors.initials: Q
authors.lastname: Wang
mesh_terms: D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D058440:Denitrification; D003901:Desulfovibrio / Q000378:metabolism; D005618:Fresh Water / Q000382:microbiology; D010084:Oxidation-Reduction; D012722:Sewage / Q000382:microbiology*; D013455:Sulfur / Q000737:chemistry*; D013885:Thiosulfates / Q000037:antagonists & inhibitors / Q000378:metabolism*; D062065:Wastewater / Q000737:chemistry*
chemical_list: D012722:Sewage; D013455:Sulfur; D013885:Thiosulfates; D062065:Wastewater
keywords: Biological thiosulfate reduction (BTR); Free sulfurous acid (FSA, H(2)SO(3)); Saline sulfite (HSO(3)(−) + SO(3)(2−)); Sulfate/sulfite-reducing bacteria (SRB)