高效脱氮除磷复合人工湿地污水处理实验研究

Experimental Study on Wastewater Treatment of Constructed Wetland with High Efficiency Nitrogen and Phosphorus Removal

为了提高人工湿地的处理效果,研究构建微曝气+复合垂直流人工湿地+氧化塘系统处理生活污水,分析复合系统对废水中COD、NH4_(+)^-N、TN及TP的去除性能,探索系统的较佳运行条件,适用范围及其沿程去除效率。结果表明,在改良的垂直流湿地水力停留时间(HRT)为2 d、曝气位置位于改良湿地前端、曝气充氧池内曝气时间为12 h的条件下,处理出水的氨氮(NH4_(+)^-N)、总氮(TN)、总磷(TP)等污染物去除效果最佳。在该运行条件下,该系统处理污水厂尾水的出水达到了《地表水环境质量标准》(GB 3838-2002)的Ⅳ级标准;处理模拟农村生活污水的出水水质满足《城镇污水处理厂污染物排放标准》(GB 18918-2002)一级A标准。研究旨在为低浓度污水的进一步处理净化研究以及高效率人工湿地系统研究提供了一定的参考。

In order to improve the treatment effect of artificial wetlands,this study was conducted to construct a microaeration+composite vertical flow artificial wetland+oxidation pond system to treat domestic wastewater,analyze the performance of the composite system on the removal of COD,NH4_(+)^-N,TN and TP in wastewater,and explore the better operating conditions,application range and removal efficiency along the process.The results showed that the best removal effect of ammonia nitrogen(NH4_(+)^-N),total nitrogen(TN),total phosphorus(TP)and other pollutants in the treated effluent was achieved under the hydraulic retention time(HRT)of 2 d,the aeration position located at the front of the modified wetland,and the aeration time in the aeration and oxygenation tank of 12 h.Under this operation condition,the effluent of the system treating the tailwater of the wastewater plant met the Class IV standard of the Environmental Quality Standard for Surface Water(GB 3838-2002).The effluent quality of the treated simulated rural domestic wastewater met the Class I A standard of the Discharge Standard for Pollutants from Urban Wastewater Treatment Plants(GB 18918-2002).The study aims to provide some references for further treatment and purification research of low-concentration wastewater as well as the research of high-efficiency artificial wetland systems.