title: Nitrogen removal from landfill leachate via ex situ nitrification and sequential in situ denitrification.
abstract: Ex situ nitrification and sequential in situ denitrification represents a novel approach to nitrogen management at landfills. Simultaneous ammonia and organics removal was achieved in a continuous stirred tank reactor (CSTR). The results showed that the maximum nitrogen loading rate (NLR) and the maximum organic loading rate (OLR) was 0.65gNl(-1)d(-1) and 3.84gCODl(-1)d(-1), respectively. The ammonia and chemical oxygen demand (COD) removal was over 99% and 57%, respectively. In the run of the CSTR, free ammonia (FA) inhibition and low dissolved oxygen (DO) were found to be key factors affecting nitrite accumulation. In situ denitrification was studied in a municipal solid waste (MSW) column by recalculating nitrified leachate from CSTR. The decomposition of MSW was accelerated by the recirculation of nitrified leachate. Complete reduction of total oxidized nitrogen (TON) was obtained with maximum TON loading of 28.6gNt(-1)TSd(-1) and denitrification was the main reaction responsible. Additionally, methanogenesis inhibition was observed while TON loading was over 11.4gNt(-1)TSd(-1) and the inhibition was enhanced with the increase of TON loading.
authors.affiliation: Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu 610041, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhong
authors.forename: Daping
authors.initials: D
authors.lastname: Li
authors.forename: Yong
authors.initials: Y
authors.lastname: Tao
authors.forename: Xiaomei
authors.initials: X
authors.lastname: Wang
authors.forename: Xiaohong
authors.initials: X
authors.lastname: He
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.forename: Jinlian
authors.initials: J
authors.lastname: Zhang
authors.forename: Weiqiang
authors.initials: W
authors.lastname: Guo
authors.forename: Lan
authors.initials: L
authors.lastname: Wang
mesh_terms: D000641:Ammonia / Q000032:analysis; D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D019149:Bioreactors; D008697:Methane / Q000096:biosynthesis; D009573:Nitrites / Q000032:analysis; D009584:Nitrogen / Q000302:isolation & purification*; D009930:Organic Chemicals / Q000302:isolation & purification*; D010100:Oxygen / Q000032:analysis; D018505:Waste Management / Q000379:methods*; D014866:Waste Products / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D009573:Nitrites; D009930:Organic Chemicals; D014866:Waste Products; D014874:Water Pollutants, Chemical; D000641:Ammonia; D009584:Nitrogen; D008697:Methane; D010100:Oxygen