多级串联表面流人工湿地对河蟹养殖尾水的净化效果研究

Purification Effect on Aquaculture Wastewater by Multi-series Surface Flow Constructed Wetland

在河蟹养殖塘边上构建了多级串联表面流人工湿地系统,研究其对河蟹养殖尾水中总氮和总磷的净化效果,以及尾水中总氮和总磷浓度的沿程衰减模型。研究结果表明,2015年7月1~6日,该人工湿地对总氮和总磷含量的去除率分别为87.03%和77.21%,说明该人工湿地能有效处理养殖尾水中的氮、磷污染物。位于人工湿地系统前端的湿地单元对总氮和总磷的去除起主要作用。随着水力负荷的提高,其对总氮和总磷的去除率减小。在建立的总氮和总磷含量与水力负荷的沿程衰减模型中,总氮的最佳拟合模型为指数衰减模型,总磷的最佳拟合模型为二次多项式模型。

The constructed wetland system with multi-cascade surface flow was constructed on the culture pond of crab, to study the effect of water purification in different systems and the variation law of total nitrogen and total phosphorus concentration along the distance. The results showed that from July 1 to 6,2015, the removal rates of total nitrogen and total phosphorus were up to 87.03% and 77.21%, respectively,which could effectively remove the nitrogen and phosphorus pollutants in aquaculture wastewater. The unit which located at the front of the artificial wetland system played a major role to remove total nitrogen and total phosphorus. The removal rates of total nitrogen and total phosphorus reduced with the hydraulic load increased. The most suitable fitting model was exponential decay model for total nitrogen, and the most suitable fitting model was quadratic polynomial model for total phosphorus.