不同停留时间下复合流人工湿地沿程净化效果的研究

A Study on the Effect of Along Purification in Hybrid Flow Constructed Wetlands under Different Residence time

采用复合流人工湿地系统净化生活污水,通过对不同处理单元段末出水水质的分析,研究了该系统在水力停留时间为12,24,36,48,60 h时,对主要水质指标降解的影响。结果表明:随着停留时间的增加,COD Cr、总氮、氨氮、总磷的去除率先增大后减小,COD Cr、总氮、氨氮同时在36 h时达到最大去除率79.87%、77.48%、82.07%,总磷在48 h时达到最大去除率91.50%;停留时间为36 h时,污染物综合去除率最高,为82.15%,其出水各指标可达城镇污水处理厂污染物排放标准(GB18918-2002)一级B标准。

In this study , the key water quality indicators of hybrid flow constructed wetlands were ana-lyzed.The residence time was 0.5 d,1 d,1.5 d and 2 d.The results showed that：with the increase of residence time,the processing efficiency of CODcr ,total ammonia ,ammonia nitrogen and total phosphorus first increased and then decreased;when the residence time was 3/2 d,the removal rates of CODcr ,total ammonia and ammo-nia nitrogen reached the maximum ,being 79.8%,77.48%and 82.07%,respectively.The removal rate of total phosphorus reached the maximum ,being 91.5%in 2 d.Each index of effluent water could meet the pollutant discharge standards of Grade 1 B,for urban sewage treatment plants （ GB18918-2002 ） .