title: [Removal nitrogen in wavy subsurface-flow constructed wetland utilizing aeration and recirculation].
abstract: To improve the removal rates of ammonium nitrogen in the constructed wetlands, the traditional wavy subsurface-flow constructed wetland (W-SFCW) was modified to install the aeration tube in the second wave interval to improve the DO and the nitrification rates within the constructed wetlands. It was found that as most of COD had been removed in the second wave interval, nitrifying bacteria become dominant in the third wave interval, which led to the nitrification extent reaching more than 90%, and the ability to endure the impact of hydraulic loading was enhanced. Recirculation rates of 50% were adopted to evaluate the effect on TN removal. It showed that with effluent recirculation the average removal efficiencies of TN obviously increased to 50% when the wastewater entered 1/3 of the wetland not infall. The hydraulic loading of wetland reached 0.8 m3/(m2 x d), and COD organic loading was 56-112 g/(m2 x d), and the ammonium loading rate was 20-28 g/(m2 x d).
authors.affiliation: School of Environmental Science & Engineering, Huazhong University of Science and Technology, Wuhan 430074, China. renyz@163.com
authors.forename: Yong-zheng
authors.initials: YZ
authors.lastname: Ren
authors.forename: Bei-ping
authors.initials: BP
authors.lastname: Zhang
authors.forename: Ben-zeng
authors.initials: BZ
authors.lastname: Hai
mesh_terms: D002244:Carbon / Q000302:isolation & purification / Q000378:metabolism; D019015:Geologic Sediments / Q000737:chemistry; D009584:Nitrogen / Q000302:isolation & purification / Q000378:metabolism*; D009930:Organic Chemicals / Q000302:isolation & purification / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000302:isolation & purification / Q000378:metabolism; D014865:Waste Disposal, Fluid / Q000379:methods*; D053833:Wetlands
chemical_list: D009930:Organic Chemicals; D000644:Quaternary Ammonium Compounds; D002244:Carbon; D009584:Nitrogen; D010100:Oxygen