厌氧池-表流湿地处理污水厂尾水的实验研究.

In order to explore the effect of hydraulic retention time (HRT) on the treatment effect of constructed wetland, the anaerobic tank surface flow constructed wetland (AT-SFCW) system was used to treat the tail water of sewage plant. The removal rules of CODcr, NH4+N, NO3- -N and TP pollutants in the system were discussed by investigating the effect of HRT change on the removal effect of pollutants. The results show that the removal efficiency of CODcr, NH4+N, NO3- -N and TP in AT-SFCW system increases first and then decreases with the extension of HRT. The optimal HRT of the system is 5 d, and the highest removal efficiency of each pollutant is 83.68%,86. 22%,88.99% and 69.87% respectively. When HRT =5 d, the concentration change of each pollutant shows that the pollutants are significantly reduced along each treatment unit, and most of CODcr and NO3- -N are removed in the anaerobic tank, which are reduced to 18. 19 mg/L and 0.29 mg/L respectively; The removal of NH-N and TP mainly occurred in the surface flow wetland, decreasing to 1.50 mg/L and 0.55 mg/L respectively. This study provides a theoretical basis for the selection of the best HRT for the combined constructed wetland. The quantitative analysis of nitrogen and phosphorus removal pathways has important guiding significance for the in-depth understanding of the law of nitrogen removal in the constructed wetland and the improvement of the removal rate of nitrogen and phosphorus. [ABSTRACT FROM AUTHOR]