潜流人工湿地中污染物沿高度变化的净化程度研究

通过人工湿地系统模拟实验考察了污染物沿高度的净化程度,分析了垂直潜流湿地系统中COD、氮、磷的去除机理及其迁移转化规律。结果表明,潜流湿地系统对COD的去除主要发生在上层(0~30 cm),主要通过好氧微生物的降解作用;对总磷的去除主要发生在上层(0~30 cm)和中层(30~60 cm),去除途径为填料的吸附和沉淀作用;对总氮的去除则发生在整个系统中,上层主要去除氨态氮,只是将氨态氮转化为亚硝态氮和硝态氮等其他形式的氮,在中层和下层进行的反硝化反应才能真正达到脱氮效果。

Purification degree of the pollutants in different depths in underflow constructed wetland

Through simulated experiments of constructed wetland systems,the purification degree of the pollutants in different depths has been investigated.The removing mechanisms of COD,nitrogen and phosphorus in the vertical underflow constructed wetland system and their moving and converting rules are analyzed.The results show that the COD removing effect of underflow wetland system mainly takes place in the upper layer (0 ~30 cm),via the degradation of aerobic microorganisms.The total phosphorus removing effect of it mainly takes place in the upper layer (0~30 cm) and middle layer(30~60 cm),mainly via adsorption and precipitation of the filling materials.The total nitrogen removing effect takes place in the whole system.Ammonia nitrogen is mainly removed in the upper layer,converting ammonia nitrogen into nitrite nitrogen and nitrate nitrogen and other forms of nitrogen.The denitrification taking place in the middle layer and lower layer can reach the real nitrogen removal result.