以模拟垂直流人工湿地为研究对象,采用正交试验法考查了在不同碳氮比(C/N)条件下,进水流量、水位高度、湿干比及运行周期4个可控因素对垂直流人工湿地脱氮的影响。结果表明,增加C/N可提高总氮去除效率,4个可控因子对污水总氮的去除有显著影响,进水量是总氮去除最重要的影响因素,干湿比的影响强度随着C/N的增大而增加,当C/N为1∶1和3∶1时,总氮的去除效果最优组合为:水位高度为50cm,湿干比为2∶1,周期为24h且进水流量为80cm·d-1;当C/N为5∶1时,总氮的去除效果最优组合为:水位高度为25cm,湿干比为1∶1,周期为24h且进水流量为80cm·d-1。
This study investigated the impacts of four different controllable factors,including inflow rate,water level,wet-to-dry ratio and operational cycle,upon the removal of nitrogen from the vertical-flow constructed wetlands under varying carbon-nitrogen(C/N)ratios,using the orthogonal experimental design.Results showed that removal efficiency of total nitrogen(TN)increased with C/N.The four different controllable factors had significant impacts on the TN removal and the inflow rate was the most important factor.The impacts of the wet-to-dry ratio increased with the C/N ratio.When the C/N ratios were 1:1 and 3:1,the optimal combination for best removal of TN was water level of 50 cm,wet-to-dry ratio of 2:1,operational cycle of 24 hours and inflow rate of 80 cm·d-1.When the C/N ratio was 5:1,the optimal combination for best removal of TN was water level of 25 cm,wet-to-dry ratio of 1:1,operational cycle of 24 hours and inflow rate of 80 cm·d-1.