title: Partial nitrification and denitrification of mature landfill leachate using a pilot-scale continuous activated sludge process at low dissolved oxygen.
abstract: Controlling of low dissolved oxygen (DO) levels (0.1-0.5mg/L), a cost-effective strategy, was applied to a pilot-scale anoxic-oxic-oxic-anoxic process for partial nitrification and denitrification of mature landfill leachate. High ammonium removal efficiency, stable nitrite accumulation rate and total nitrogen removal efficiency was higher than 95.0%, 90.0% and 66.4%, respectively, implying potential application of this process for nitrogen removal of mature landfill leachate. Efficient nitrite accumulation in the first oxic reactor depended on low DO conditions and sufficient alkalinity. However, operational limit was mainly decided by actual hydraulic retention time (AHRT) of the first oxic reactor and appeared with AHRT less than 13.9h under DO of 0.3-0.5mg/L. High-throughput sequencing analysis demonstrated significant change of bacterial diversity in the first oxic reactor after a long-term operation and dominant bacteria genus Nitrosomonas was shown to be responsible for NH4(+)-N removal and nitrite accumulation under low DO levels.
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China.
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Chen
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China. Electronic address: cexjwang@scut.edu.cn.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wang
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China.
authors.forename: YongYuan
authors.initials: Y
authors.lastname: Yang
authors.affiliation: School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China.
authors.forename: Markus W
authors.initials: MW
authors.lastname: Mirino
authors.affiliation: Hualu Environmental Technology Co., Ltd., Guangzhou, China.
authors.forename: Yanlei
authors.initials: Y
authors.lastname: Yuan
mesh_terms: D064751:Ammonium Compounds / Q000378:metabolism; D001419:Bacteria / Q000254:growth & development / Q000378:metabolism; D019149:Bioreactors / Q000382:microbiology; D058440:Denitrification / Q000502:physiology*; D058465:Nitrification / Q000502:physiology*; D009573:Nitrites / Q000378:metabolism; D009584:Nitrogen / Q000378:metabolism; D009606:Nitrosomonas / Q000254:growth & development / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry*; D010865:Pilot Projects; D012722:Sewage / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000378:metabolism
chemical_list: D064751:Ammonium Compounds; D009573:Nitrites; D012722:Sewage; D014874:Water Pollutants, Chemical; D009584:Nitrogen; D010100:Oxygen
keywords: Bacterial community analysis; Low dissolved oxygen; Mature landfill leachate; Nitrite pathway; Nitrogen removal