【摘要】 对自由表面人工湿地去除农业面源污水中氮的效果及途径进行了研究 ,结果表明 ,脱氮效率随水力停留时间(HRT)延长而增加 ,HRT为 0 5、1、2和 3d时 ,系统总氮去除率分别为 18 3 %、3 8 9%、84 9%和 85 6%。HRT <2d ,出水水质波动较大 ,2d以上 ,系统即可高效稳定运行。硝化 /反硝化是湿地脱氮的主要途径 ,挥发和填料吸附脱氮量可以忽略 ,依靠植物吸收可以去除一部分氮 ,茭草 (Zizaniacaduciflora)和芦苇 (Phragmitascommunis)的氮吸收量每年分别为 44 0和70 0kgN/hm2 。更多还原

【Abstract】 Nitrogen removal in treating agricultural non-point wastewater using surface constructed wetland was studied in pilot-scale. The experimental results showed that the removal rate of TN increases with HRT increasing, and that the removal rates of TN were 18.3%?38.9%?84.9% and 85.6% when the hydraulic retention times were 0.5?1?2?3 days respectively. HRT<2 d, effluent is not stable, HRT 2 d, the system performance is very good. Nitrification and denitrification are the main removal ways of total nitrogen. Volatilization and adsorption effects can be ignored. The amounts of TN that can be removed by harvesting Zizania caduciflora and Phragmitas communis are about 440 and 700 kg N/ha/yr respectively.更多还原