title: Autotrophic denitrification by nitrate-dependent Fe(II) oxidation in a continuous up-flow biofilter.
abstract: A continuous-upflow biofilter packed with sponge iron was constructed for nitrate removal under an anaerobic atmosphere. Microbacterium sp. W5, a nitrate reducing and Fe(II) oxidizing strain, was added to the biofilter as an inoculum. The best results were achieved when NO3 (-)-N concentration was 30 mg/L and Fe(2+) was 800 mg/L. Nitrite in influent would inhibit nitrate removal and aqueous Fe(2+) resulted in encrustation. Fe(II)EDTA would prevent cells from encrustation and the maximum nitrogen removal efficiency was about 90 % with Fe(II)EDTA level of 1100 mg/L. Nitrate reduction followed first-order reaction kinetics. Characteristics of biofilms were analyzed by X-ray fluorescence spectroscopy.
authors.affiliation: School of Civil Engineering, Wuhan University, Wuhan, 430072, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Zhou
authors.affiliation: School of Civil Engineering, Wuhan University, Wuhan, 430072, China. wanghywhu@163.com.
authors.forename: Hongyu
authors.initials: H
authors.lastname: Wang
authors.affiliation: School of Civil Engineering, Wuhan University, Wuhan, 430072, China. kaiyangchn@126.com.
authors.forename: Kai
authors.initials: K
authors.lastname: Yang
authors.affiliation: School of Urban Construction, Wuhan University of Science and Technology, Wuhan, 430081, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Ji
authors.affiliation: School of Civil Engineering, Wuhan University, Wuhan, 430072, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Chen
authors.affiliation: School of Civil Engineering, Wuhan University, Wuhan, 430072, China.
authors.forename: Huining
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Northeast Electric Power Design Institute, Changchun, 130000, China.
authors.forename: Yuchong
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Central and Southern China Municipal Engineering Design and Research Institute, Wuhan, 430010, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Tian
mesh_terms: D039903:Actinobacteria / Q000378:metabolism*; D000693:Anaerobiosis; D058440:Denitrification / Q000502:physiology*; D007501:Iron / Q000378:metabolism*; D009566:Nitrates / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D009566:Nitrates; D007501:Iron
keywords: Continuous-upflow biofilter; Encrustation; Nitrate removal; Nitrate-dependent Fe(II) oxidation