title: Performance of nitrate-dependent anaerobic ferrous oxidizing (NAFO) process: a novel prospective technology for autotrophic denitrification.
abstract: Nitrate-dependent anaerobic ferrous oxidizing (NAFO) is a valuable biological process, which utilizes ferrous iron to convert nitrate into nitrogen gas, removing nitrogen from wastewater. In this work, the performance of NAFO process was investigated as a nitrate removal technology. The results showed that NAFO system was feasible for autotrophic denitrification. The volumetric loading rate (VLR) and volumetric removal rate (VRR) under steady state were 0.159±0.01 kg-N/(m(3) d) and 0.073±0.01 kg-N/(m(3) d), respectively. In NAFO system, the effluent pH was suggested as an indicator which demonstrated a good correlation with nitrogen removal. The nitrate concentration was preferred to be less than 130 mg-N/L. Organic matters had little influence on NAFO performance. Abundant iron compounds were revealed to accumulate in NAFO sludge with peak value of 51.73% (wt), and they could be recycled for phosphorus removal, with capacity of 16.57 mg-P/g VS and removal rate of 94.77±2.97%, respectively.
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China. Electronic address: pzheng@zju.edu.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Zheng
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Ru
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Ding
authors.affiliation: Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
authors.forename: Ghulam
authors.initials: G
authors.lastname: Abbas
mesh_terms: D000693:Anaerobiosis; D052818:Autotrophic Processes; D001709:Biotechnology / Q000379:methods*; D058440:Denitrification; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000378:metabolism*; D009566:Nitrates / Q000737:chemistry* / Q000302:isolation & purification; D009930:Organic Chemicals / Q000302:isolation & purification; D010084:Oxidation-Reduction; D010758:Phosphorus / Q000302:isolation & purification; D012722:Sewage / Q000737:chemistry; D014835:Volatilization; D014865:Waste Disposal, Fluid
chemical_list: D009566:Nitrates; D009930:Organic Chemicals; D012722:Sewage; D010758:Phosphorus; D007501:Iron
keywords: Autotrophic denitrification; NAFO; Operation conditions; Process mechanism; Working performance