人工湿地处理城市污水启动期运行特性

选取4种植物(鸢尾、香蒲、麦冬和美人蕉)和3种基质(炉渣、沸石和砾石),通过植物和基质的不同组合构建了7组潜流型人工湿地,研究不同植物、相同基质及不同基质、相同植物条件下,湿地处理城市污水的启动期运行特性。结果表明,对COD去除率,砾石>炉渣>沸石,美人蕉>鸢尾>香蒲>麦冬;对TN去除率,沸石>砾石>炉渣,美人蕉>香蒲>麦冬>鸢尾;对NH4+-N去除率,沸石>砾石>炉渣,香蒲>美人蕉>麦冬>鸢尾;对TP去除率,炉渣>砾石>沸石,香蒲>美人蕉>鸢尾>麦冬。植物种植前,炉渣、沸石和砾石不同基质湿地的COD去除率没有明显差异;在TN和NH4+-N的去除上,沸石远优于炉渣和砾石。植物种植后,3种基质的TP去除率在10.75%左右。鸢尾、麦冬和美人蕉3种植物湿地的COD去除率随运行历程呈上升趋势,而香蒲由于生长状况不佳,去除率呈下降趋势。美人蕉湿地TN去除率较其它3种植物湿地高,各植物湿地NH4+-N去除率差异不显著。4种植物湿地TP去除率在9.24%左右。

Operation characteristics during start-up period by sewage treatment system of subsurface constructed wetlands

In order to study the operation characteristics for treating urban wastewater during the wetland's start-up,7 subsurface flow constructed wetlands were built with different combinations of the four plants(iris,bulrushes,radix ophiopogonis and canna) and three substrates(slag,zeolite and gravel).Comparing the constructed wetlands with different substrates or plants, it can be found that the removal rates of COD,gravel>slag>zeolite,canna>iris>bulrushes>radix ophiopogonis. When it refers to the removal rates of TN,zeolite>gravel>slag,canna>bulrushes>radix ophiopogonis>iris.The removal rates of NH₄⁺-N,zeolite>gravel>slag,bulrushes>canna>radix ophiopogonis>iris.The removal rates of TP,slag>gravel>zeolite,bulrushes>canna>iris>radix ophiopogonis. There are no obvious differences among the removal rates of COD of three substrates(slag,zeolite,gravel)with and without the plant while it refers to TN and NH₄⁺-N,zeolite were far better than the slag and gravel. After the plants were planted,the removal rates of TP of the three substrates were all at the level of some 10.75%. As the wetlands ran, the removal rates of COD of the three plants(iris,radix ophiopogonis and canna) increased,while the removal rates of COD of bulrushes declined because of its bad growing situation. Canna was the best in removal of TN,and the differences among the plants' abilities to move NH₄⁺-N were not apparent. The removal rates of TP of the four plants were all about 9.24%.