三段式潜流湿地污水净化效果

WASTEWATER PURIFICATION WITH THREE-SEGEMENT SUBSURFACE WETLANDS

对传统水平流湿地加以改造,形成三段式潜流湿地,并采用自然接触富氧和微曝气强化供氧。比较了传统水平流湿地、三段式自然富氧潜流湿地及三段式微曝气潜流湿地的DO分布及对生活污水的处理效果。实验结果表明:三段式自然富氧潜流湿地由于改善了湿地供氧状况,COD、NH4+-N和TN最高去除率分别达到92%、70%、56%,优于传统水平流湿地;采用微曝气进一步强化供氧可有效改善系统溶氧分布,延展最佳HRT的控制范围,COD、NH4+-N和TN去除率分别达到了96%、83%、65%,而且土壤脲酶活性明显提高,在较低运行水位下仍能保持较高的污染物去除效果。但新型湿地除磷效果提高不明显。三段式微曝气潜流湿地的研究为人工湿地污水处理技术探索了一条新的途径。

Traditional horizontal-flow constructed wetland was rebuilt to form a new type of wetland construction, i.e., three-segment subsurface flow wetland, in which natural oxygen-richening and slight-aeration enhancing for oxygen supply was adopted. The DO distribution and wastewater treatment effect were compared in traditional wetland and three-segment subsurface flow wetland supplying oxygen by natural or slight-aeration in contact gutters. Results showed that the removal efficiency of COD,NH4^＋-N and TN separately reached to 92% ,70% and 56% in three-segment subsurface flow wetland, while they were 96%,83% and 65% in slight-aeration system. When slight-aerated, the urease activity rose obviously and could keep higher removal effect of pollutants below operating water level still, but the phosphorus removal of new wetlands didn＇t rose obviously. The research on three segment type slight aeration subsurface wetland is a new way to enquire into the sewage treatment by constructed wetland.