垂直流人工湿地的设计及净化功能初探

Design and purification performance of vertical flow constructed wetland.

阐述了垂直流人工湿地小试系统的设计 ,并测试其冬季污水净化效果 .垂直流人工湿地由下行流和上行流方式的两池组成 .对受污染地面水体中的CODCr、BOD5和TSS的去除率分别为 5 3.6 %、78.7%和 80 .2 % .对细菌、总大肠菌、粪大肠菌和藻类的平均去除率分别达 99.4%、85 .9%、89.7%和 97.7% .对KN、NH+ 4 N和TP的平均去除率分别为 39.2 %、16 .5 %和 2 5 .8% .各系统对污染物的去除作用无明显差异 .系统出水NO-3 N浓度高于进水 ,而有植物系统中又高于无植物的对照 ,表明湿地植物的存在有利于硝化作用 .表明下行流 上行流人工湿地在冬季仍能较好地改善水质 ,是一种有效的水处理技术 。

The technical design of small-scale plots (SSPs) of constructed wetland (CW) was described along with details of some associated wastewater purification effects in winter. Plots were comprised of two chambers. One chamber induced downward-flow,while the other created upward-flow. During Oct. 1997～Jan. 1998,the average plot removal rates for COD Cr,BOD 5 and total suspended solids were 53.6%,78.7% and 80.2%,respectively. Reductions of bacteria,total coliforms (TC),fecal coliforms (FC) and algae were 99.4%,85.9%,89.7% and 97.7%,respectively. The mean removal rates of Kjeldahl nitrogen (KN),ammonium (NH + 4-N) and total phosphorus (TP) were 39.2%,16.5% and 25.8%. The treatment effects were not significantly different from each other. Concentrations of nitrate (NO - 3-N) in effluents were higher than those of the influent,and nitrate concentrations in the effluents of plant-systems were higher than those of the control. This indicated that presence of macrophytes enhanced nitrification in the CW. The downward followed by upward flow CW performed better in removing contaminants and microorganisms from polluted surface water. It is an improved technology to purify water quality and rehabilitation of aquatic ecosystems.