流型、植物种类和基质厚度对人工湿地去除废水中氨氮的影响

实验模拟人工湿地,以沙、土混合物为基质,比较了水平潜流和垂直流、不同植物、不同基质厚度对氨氮(NH_4~+-N)处理效果的影响,并分别进行了分析。实验表明,水平潜流和垂直流NH_4~+-N去除率分别达到59%和68%,垂直流人工湿地处理效果较好的原因是垂直流为硝化创造了有利的条件。金边吊兰、金钱草、绿萝对NH_4~+-N的平均去除率依次为46%、60%和70%,分析认为根系是影响NH_4~+-N去除效果的主要因素。以金钱草做湿地植物,基质厚度为6 cm时去除效果最好,最大去除率达到74%,表明基质厚度与植物根系长度相适应时,NH_4~+-N的去除效果最佳。研究结果为深化湿地去除NH_4~+-N的理论研究和应用推广提供了支撑。

Flow pattern, plant species and substrate thickness on the removal of ammonia nitrogen from wastewater by Constructed Wetland

The simulation of constructed wetland was established with sand and soil mixture as substrate. The effect of ammonia nitrogen (NH₄₊-N) removing was compared using subsurface horizontal subsurface flow and vertical flow, different plants, and different substrate thickness. Experimental results show that the NH₄₊-N removal rate of horizontal subsurface flow and vertical flow reached 59% and 68% respectively. The reason of vertical flow constructed wetland is better was because of vertical flow have created favorable conditions for nitrification. NH₄₊-N average removal rate of Chlorophytum Phnom Penh, Herba Lysimachiae, and Scindapsus aureus is 46%, 60%, and 70% respectively. It is thought that root be the main factors influencing the effect of NH₄₊-N removal. NH₄₊-N removal rate reached 74% when the substrate thickness is 6cm withSHerba Lysimachiae as wetland plant. It shows that NH₄₊-N removal effect is best as the thickness of the substrate adapted to plant roots length. The results deepened the theory of removal NH₄₊-N using the wetland and provided support for application promotion.