title: Intensified nitrogen removal in immobilized nitrifier enhanced constructed wetlands with external carbon addition.
abstract: Nitrogen removal performance response of twelve constructed wetlands (CWs) to immobilized nitrifier pellets and different influent COD/N ratios (chemical oxygen demand: total nitrogen in influent) were investigated via 7-month experiments. Nitrifier was immobilized on a carrier pellet containing 10% polyvinyl alcohol (PVA), 2.0% sodium alginate (SA) and 2.0% calcium chloride (CaCl2). A batch experiment demonstrated that 73% COD and 85% ammonia nitrogen (NH4-N) were degraded using the pellets with immobilized nitrifier cells. In addition, different carbon source supplement strategies were applied to remove the nitrate (NO3-N) transformed from NH4-N. An increase in COD/N ratio led to increasing reduction in NO3-N. Efficient nitrification and denitrification promoted total nitrogen (TN) removal in immobilized nitrifier biofortified constructed wetlands (INB-CWs). The results suggested that immobilized nitrifier pellets combined with high influent COD/N ratios could effectively improve the nitrogen removal performance in CWs.
authors.affiliation: College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, China; Department of Environmental Health Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1771, United States.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, China; College of Ocean Science and Engineering, Shanghai Maritime University, Shanghai 201306, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Ding
authors.affiliation: College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, China. Electronic address: yhwang@dhu.edu.cn.
authors.forename: Yuhui
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai 201620, China.
authors.forename: Xinshan
authors.initials: X
authors.lastname: Song
authors.affiliation: Department of Environmental Health Sciences, University of California, Los Angeles, Los Angeles, CA 90095-1771, United States.
authors.forename: Richard F
authors.initials: RF
authors.lastname: Ambrose
authors.affiliation: Department of Biological Systems Engineering, Washington State University, P.O. Box 646120, Pullman, WA 99164, United States.
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Ullman
mesh_terms: D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D058440:Denitrification; D058465:Nitrification; D009584:Nitrogen / Q000737:chemistry*; D053833:Wetlands
chemical_list: D009584:Nitrogen
keywords: Biofortification; COD/N ratio; Constructed wetlands; Immobilized pellet; Nitrification-denitrification