title: Simultaneous removal of organic matter and nitrogen by a heterotrophic nitrifying-aerobic denitrifying bacterial strain in a membrane bioreactor.
abstract: A heterotrophic nitrifying-aerobic denitrifying bacterial strain, Bacillus methylotrophicus L7, was inoculated solely into a submerged membrane bioreactor (MBR) for continuous treatment of artificial sewage. The running conditions were also optimized for improvement of the treatment efficiency. The results indicated that inoculation of this single strain in a single reactor under constant aerobic conditions resulted in simultaneous removal of organic matter and nitrogen, in striking contrast to traditional aerobic nitrification-anaerobic denitrification treatment system and the sequencing batch reactor (SBR) systems. The optimal running conditions for the MBR were dissolved oxygen (DO) 4.5 mg/L, pH 7.5, loading ammonia <100 mg/L, and C/N ratio 3.5. Under these conditions, the removal percentages of chemical oxygen demand (COD), NH4(+)-N, and TN as high as 96%, 77.5% and 53%, respectively, were achieved without nitrite accumulation.
authors.affiliation: State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China.
authors.forename: Yan-Chun
authors.initials: YC
authors.lastname: Yao
authors.forename: Qing-Ling
authors.initials: QL
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Zhi-Pei
authors.initials: ZP
authors.lastname: Liu
mesh_terms: D000332:Aerobiosis; D019149:Bioreactors; D006863:Hydrogen-Ion Concentration; D008567:Membranes, Artificial; D009584:Nitrogen / Q000302:isolation & purification*; D062065:Wastewater
chemical_list: D008567:Membranes, Artificial; D009584:Nitrogen; D062065:Wastewater
keywords: Bacillus methylotrophicus L7; Heterotrophic nitrification–aerobic denitrification; MBR; Simultaneous removal of organic matter and nitrogen