人工湿地净化富营养化河水试验研究(二)——基质层及流态对氮素污染物净化效果的影响

Pilot-scale Experimental Study on Eutrophicated River Purification by Constructed Wetlands(2)--Effects of Bed and Flow Designs on Nitrogen Removal

通过中试试验研究了基质层及流态对人工湿地净化富营养化河水中氮素污染物的影响情况,结果表明:砾石基质层厚度从80cm增加到120cm对湿地池净化氮素污染物的效果没有明显影响;将上层砾石替换为沸石后,湿地池对NH3-N的净化效果明显提高,说明不同的基质材料对NH4+具有良好的选择性吸附作用,而将上层砾石替换为炉渣后湿地池对氮素污染物的净化效果几乎没有变化;在4种湿地流态中,复合流态(垂直流+潜流)湿地池对TN、NH3-N、NO3-N的去除率均为最高,且与潜流-垂直流相前后次序没有显著相关性;潜流、垂直流湿地池对氮素污染物的去除率介于复合流、表面流之间;表面流最低。

It was investigated for effects of bed and flow types on nitrogen pollutants purification by constructed wetlands in the pilot-scale system. When gravel bed depth of construted wetlands was increased from 80cm to 120cm, nitrogen removal efficiency was not changed obviously. When gravel bed at surface was displaced by zeolite, ammonia nitrogen removal efficiency was increased obviously because of excellent selective adsorption of ammonium ions onto zeolite. Among four flow types designed, the integrated flow type （vertical plus subsurface） constructed wetlands had the highest nitrogen removal efficiency, free-surface flow constructed wetland had the lowest nitrogen removal efficiency.