title: Characteristics of heterotrophic/biofilm-electrode autotrophic denitrification for nitrate removal from groundwater.
abstract: A heterotrophic/biofilm-electrode autotrophic denitrification reactor (HAD-BER) was developed to improve denitrification efficiency and reduce the consumption of organic carbon source. Maximum nitrate removal efficiency of 99.9% was gained under the optimum current density of 200 mA/m(2). The number of heterotrophic denitrification bacteria (HDB) 2.0 × 10(5) and hydrogen autotrophic denitrification bacteria (ADB) 2.0 × 10(3) in per milliliter biofilm solution were observed by the most probable number (MPN) culture, demonstrating that HDB and ADB coexist in the HAD-BER. The inorganic carbon source for autotrophic denitrification was supplied by the dissolved carbon dioxide (CO2) evolved from the heterotrophic denitrification process, indicating that there was synergistic interaction between the HDB and ADB, i.e., the organic carbon source used for denitrification could be decreased in the HAD-BER. Therefore, the developed HAD-BER would be a promising approach for nitrate removal from groundwater.
authors.affiliation: Key Laboratory of Groundwater Circulation and Evolution, China University of Geosciences Beijing, Ministry of Education, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences Beijing, Beijing 100083, China.
authors.forename: Shuang
authors.initials: S
authors.lastname: Tong
authors.forename: Baogang
authors.initials: B
authors.lastname: Zhang
authors.forename: Chuanping
authors.initials: C
authors.lastname: Feng
authors.forename: Yingxin
authors.initials: Y
authors.lastname: Zhao
authors.forename: Nan
authors.initials: N
authors.lastname: Chen
authors.forename: Chunbo
authors.initials: C
authors.lastname: Hao
authors.forename: Jiaoyang
authors.initials: J
authors.lastname: Pu
authors.forename: Liwei
authors.initials: L
authors.lastname: Zhao
mesh_terms: D000641:Ammonia / Q000378:metabolism; D052818:Autotrophic Processes; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D001673:Biodegradation, Environmental; D018441:Biofilms / Q000254:growth & development*; D057919:Biological Oxygen Demand Analysis; D019149:Bioreactors / Q000382:microbiology; D002245:Carbon Dioxide / Q000032:analysis; D015169:Colony Count, Microbial; D058440:Denitrification; D004560:Electricity; D004566:Electrodes; D060587:Groundwater / Q000737:chemistry*; D052836:Heterotrophic Processes; D009566:Nitrates / Q000302:isolation & purification*; D009573:Nitrites / Q000378:metabolism
chemical_list: D009566:Nitrates; D009573:Nitrites; D002245:Carbon Dioxide; D000641:Ammonia
keywords: HAD-BER; Heterotrophic denitrification bacteria; Hydrogen autotrophic denitrification bacteria; Nitrate reduction; Symbiotic environment