title: Simultaneous partial nitrification, anaerobic ammonium oxidation and denitrification (SNAD) in a full-scale landfill-leachate treatment plant.
abstract: The occurrence of simultaneous partial nitrification, anaerobic ammonium oxidation and denitrification (SNAD) observed in a single partially aerated full-scale bioreactor treating landfill-leachate is reported in this paper. At present, the full-scale bioreactor is treating an average leachate flow of 304 m(3)d(-1) with a sludge retention time between 12 and 18d. The average COD, NH(4)(+)-N and NO(3)(-)-N concentrations at the upstream end of the bioreactor, i.e., influent, are 554, 634 and 3 mg L(-1), respectively; whereas no NO(2)(-)-N is detected in the influent. The percentage removals of COD and NH(4)(+)-N in the bioreactor were 28% and 80%, respectively. A nitrogen mass balance approach was adopted to analyze the performance of SNAD in the full-scale bioreactor. The total nitrogen (TN) removal by combined partial nitrification and anaerobic ammonium oxidation is 68% and the heterotrophic denitrification contributes to 8% and 23% of TN and COD removals, respectively. The red granule in the bioreactor was analyzed by using fluorescence in situ hybridization and polymerase chain reaction. The results of both analytical methods confirm the presence of anaerobic ammonium oxidizing bacteria as the predominant species along with other Planctomycete-like bacteria. Overall, the SNAD process offers the simultaneous removals of nitrogen and COD in the wastewater.
authors.affiliation: Institute of Environmental Engineering, National Chiao Tung University, 1001 University Road, Hsinchu 30010, Taiwan, ROC. chihcheng.ev90g@nctu.edu.tw
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Wang
authors.forename: Po-Heng
authors.initials: PH
authors.lastname: Lee
authors.forename: Mathava
authors.initials: M
authors.lastname: Kumar
authors.forename: Yu-Tzu
authors.initials: YT
authors.lastname: Huang
authors.forename: Shihwu
authors.initials: S
authors.lastname: Sung
authors.forename: Jih-Gaw
authors.initials: JG
authors.lastname: Lin
mesh_terms: D000641:Ammonia / Q000737:chemistry; D000693:Anaerobiosis; D001421:Bacteria, Anaerobic; D001673:Biodegradation, Environmental; D019149:Bioreactors; D017404:In Situ Hybridization, Fluorescence; D009584:Nitrogen / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D016133:Polymerase Chain Reaction; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012037:Refuse Disposal / Q000379:methods; D012722:Sewage; D012989:Soil Pollutants / Q000302:isolation & purification; D013624:Taiwan; D013997:Time Factors
chemical_list: D000644:Quaternary Ammonium Compounds; D012722:Sewage; D012989:Soil Pollutants; D000641:Ammonia; D009584:Nitrogen; D010100:Oxygen