表流-水平流复合人工湿地对高污染河水的净化

Purification of highly polluted river water using surface-horizontal subsurface flow hybrid constructed wetlands

为了研究表流-水平流复合人工湿地对高污染河水的净化效果及植物对复合湿地中二级潜流湿地的影响作用,实验构建了表流＋芦苇水平潜流和表流＋无植物水平潜流复合人工湿地。在相同的水力负荷下连续运行一年的结果表明,复合人工湿地对高污染河水中TN、NH3-N、TP、COD、BOD5和SS的去除率分别为57.3%～63.1%、65.7%～68.1%、69.4%～82.7%、85.3%～86.3%、96.7%～96.9%和97.9%～98.2%,种有植物的二级潜流湿地具有更好的脱氮和除磷效果;表流湿地作为复合湿地的第一级能够有效去除大部分的有机污染物和悬浮物,进而避免二级潜流湿地的堵塞,并利于二级潜流湿地的脱氮除磷的进行;复合湿地对有机物和悬浮物的去除不受季节性波动的影响,但是其脱氮效果受季节波动的影响较大。

In order to investigate the pollutants removal efficiencies of the surface-horizontal subsurface flow（ HF） hybrid constructed wetland（ HCW） treating the highly polluted river and the roles of the plants in the second stage HFCW,two hybrid constructed wetlands which were composed of FWS ＋ HF（ with Phragmites） and FWS ＋ HF（ without plants） were constructed and operated under the same hydraulic loading. During one year＇s experiment,the average removal rates of TN,NH3-N,TP,COD,BOD5 and SS were 57. 3% —63. 1%,65. 7% —68. 1%,69. 4% —82. 7%,85. 3% —86. 3%,96. 7% —96. 9% and 97. 9% —98. 2%,respectively.The removal efficiencies of nitrogen and phosphorus in the planted HF were higher than the unplanted HF. As the first stage of the HCW,FWS removed most of organic and SS which avoided the clogging of the HF and improved the removal of the nitrogen and phosphorus in the second stage wetland. The removal of organic pollutants and suspended solids in the HCW were not affected by seasonal fluctuation,but the removal of nitrogen was influenced by seasonal fluctuation significantly.