title: [Removal efficiency of nitrogen in aerobic/anaerobic subsurface flow constructed wetlands].
abstract: In order to adjust the dissolved oxygen in the traditional subsurface flow constructed wetlands (SFCWs) and increase the purification efficiency of sewage water, the traditional SFCWs were divided into different sections with enhanced functions. Different kinds of aerobic/anaerobic SFCWs were designed to study the influence of ratio and location of aerobic/anaerobic, artificial aeration and other factors on the nitrogen in effluent. The purification efficiency of the water in this study was compared with that in traditional SFCWs. The results showed that the removal efficiencies of NH4(+)-N and TN in traditional SFCWs were 18.4% and 40.6% but 99.7% and 50.7% in aerobic/anaerobic/aerobic SFCWs with aeration (O-A-O SFCWs with aeration) treatment. Aeration in the front and in the rear, and anaerobic treatment in the middle was used in this treatment. Removal efficiency of NH4(+)-N in O-A-O SFCWs with aeration treatment was 100%, while that of O-A-O SFCWs without aeration was about 50%. The removal efficiencies of NH4(+) -N in new SFCWs with aeration in the front and in the rear were increased by 82.81% and 17.91% but 73.16% in the middle. It shows that aeration can significantly improve the removal efficiency of nitrogen, especially NH4(+)-N. Aeration in the front and back can greatly improve the removal efficiency NH4(+)-N and TN. But aeration resulting to oxygen-rich environment is not conducive to the denitrification, which will be an important factor of limiting the TN removal efficiency.
authors.affiliation: College of Environmental Science and Engineering, Ocean University of China, Qingdao 266100, China. lfm01@ouc.edu.cn
authors.forename: Feng-Min
authors.initials: FM
authors.lastname: Li
authors.forename: Shi
authors.initials: S
authors.lastname: Shan
authors.forename: Hao-Yun
authors.initials: HY
authors.lastname: Wang
authors.forename: Ni
authors.initials: N
authors.lastname: Song
authors.forename: Zhen-Yu
authors.initials: ZY
authors.lastname: Wang
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D004785:Environmental Pollutants / Q000302:isolation & purification*; D009584:Nitrogen / Q000737:chemistry / Q000302:isolation & purification*; D053833:Wetlands
chemical_list: D004785:Environmental Pollutants; D009584:Nitrogen