title: Biological denitrification process based on the Fe(0)-carbon micro-electrolysis for simultaneous ammonia and nitrate removal from low organic carbon water under a microaerobic condition.
abstract: A combined process between micro-electrolysis and biological denitrification (MEBD) using iron scraps and an activated carbon-based micro-electrolysis carrier was developed for nitrogen removal under a microaerobic condition. The process provided NH4(+)-N and total nitrogen (TN) removal efficiencies of 92.6% and 95.3%, respectively, and TN removal rate of 0.373±0.11kgN/(m(3)d) at corresponding DO of 1.0±0.1mg/L and HRT of 3h, and the optimal pH of 7.6-8.4. High-throughput sequencing analysis verified that dominant classes belonged to β-, α-, and γ-Proteobacteria, and Nitrospira. The dominant genera Hydrogenophaga and Sphaerotilus significantly increased during the operation, covering 13.2% and 6.1% in biofilms attached to the carrier in the middle of the reactor, respectively. Autotrophic denitrification contributed to >80% of the TN removal. The developed MEBD achieved efficient simultaneous nitrification and autotrophic denitrification, presenting significant potential for application in practical low organic carbon water treatment.
authors.affiliation: School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, PR China; Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Beijing 100044, PR China.
authors.forename: Shihai
authors.initials: S
authors.lastname: Deng
authors.affiliation: School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, PR China; Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Beijing 100044, PR China. Electronic address: dsli@bjtu.edu.cn.
authors.forename: Desheng
authors.initials: D
authors.lastname: Li
authors.affiliation: School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, PR China; Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Beijing 100044, PR China.
authors.forename: Xue
authors.initials: X
authors.lastname: Yang
authors.affiliation: School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, PR China; Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Beijing 100044, PR China.
authors.forename: Wei
authors.initials: W
authors.lastname: Xing
authors.affiliation: School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, PR China; Beijing Key Laboratory of Aqueous Typical Pollutants Control and Water Quality Safeguard, Beijing 100044, PR China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Li
authors.affiliation: School of Civil Engineering, Beijing Jiaotong University, Beijing 100044, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D000332:Aerobiosis; D000641:Ammonia / Q000737:chemistry*; D052818:Autotrophic Processes; D001419:Bacteria / Q000235:genetics / Q000378:metabolism*; D018441:Biofilms; D019149:Bioreactors / Q000382:microbiology; D002244:Carbon / Q000737:chemistry*; D058440:Denitrification; D004572:Electrolysis / Q000379:methods*; D059014:High-Throughput Nucleotide Sequencing; D007501:Iron / Q000737:chemistry; D059013:Microbial Consortia / Q000235:genetics / Q000502:physiology; D009566:Nitrates / Q000737:chemistry*; D058465:Nitrification; D009584:Nitrogen / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D062065:Wastewater / Q000737:chemistry
chemical_list: D000641:Ammonia; D002244:Carbon; D007501:Iron; D009566:Nitrates; D009584:Nitrogen; D062065:Wastewater
keywords: Autotrophic denitrification; Electron donor production; Fe(0)–carbon micro-electrolysis; Low organic carbon wastewater; Microbial communities