人工湿地-灯心草处理系统对高浓度重金属污水的净化效果研究

以搭建垂直流人工湿地系统并种植湿地植物(灯芯草)为研究对象,研究人工湿地基质以及湿地植物对重金属Cd、Pb的富集特性,分析了重金属在植物体和土壤中的动态分布,以评价灯芯草对重金属Cd、Pb的综合富集能力以及人工湿地系统对复合重金属污水的净化效果,为利用植物修复金属污染土壤提供理论依据和技术支持。结果显示,湿地植物(灯芯草)对复合重金属Cd、Pb的富集特性高于湿地基质的富集特性。此外湿地植物(灯芯草)的根、茎、叶对重金属Cd、Pb的富集能力也各有不同,其中灯芯草根部对重金属Cd、Pb的富集效果明显大于茎、叶。对于湿地基质,其表层、中层、下层对重金属Cd、Pb的富集效果也有所差异,其表层基质对重金属Cd、Pb的富集效果明显大于中层、下层。湿地土壤基质及湿地植物(灯芯草)对复合重金属Cd、Pb污染的净化有一定作用,其中以湿地植物(灯芯草)根部及湿地表层基质净化效果较为最佳,对污水中Cd、Pb的去除率分别达到69.5%及72.3%,净化效果较好。

Study on purification effect of artificial wetland(rushes) on heavy metal wastewater

This research is to set up the vertical flow constructed wetland system and wetland plant( rushes) as the research object, research constructed wetland substrate and wetland plant enrichment characteristics of heavy metal Cd, Pb, the dynamic analysis of heavy metals in plants and soil distribution,evaluation rushes to the enrichment of the comprehensive ability of heavy metal Cd, Pb and artificial wetland system, the effect of compound of heavy metal sewage purification provide theoretical basis for the use of phytoremediation of metal polluted soil and technical support. The results showed that the enrichment of Cd and Pb in wetland plants( rushes) was higher than that in wetland substrate. In addition, the root,stem and leaf of wetland plants(rushes) have different enrichment capacities for heavy metal Cd and Pb.Among them, the root of rushes has significantly higher enrichment capacities for heavy metal Cd and Pb than the stem, leaf and tip. For wetland matrix, the enrichment effect of surface layer, middle layer and lower layer on heavy metal Cd and Pb is also different, and the enrichment effect of surface layer matrix on heavy metal Cd and Pb is significantly greater than that of middle layer and lower layer. Wetland soil substrate and wetland plants(rushes) have a certain effect on the purification of complex heavy metal Cd and Pb pollution, among which the roots of wetland plants(rushes) and wetland surface matrix have the best purification effect, and the removal rate of Cd and Pb in sewage reaches 69.5% and 72.3% respectively, with better purification effect.