不同基质填充度模块化人工湿地强化脱氮除磷效果研究

Nitrogen and Phosphorus Removal Effect of a Novel Modular Constructed Wetland with Different Substrate Filling Factors

构建了基于有机、无机基质混合的新型组合式模块化人工湿地(MCW),开展深度处理模拟污水处理厂尾水的研究.模块化人工湿地由前后串联的两级单元组成,以陶粒、生物炭和砾石为基质,其中第一级单元陶粒按照体积百分比为90%、60%和30%分别设置3组,第二级单元填充同第一级相同体积的陶粒,其余体积填充生物炭.结果表明:3组模块化人工湿地对总氮(TN)、硝酸盐(NO_(3)^(-)-N)和总磷(TP)的去除率均显著高于对照组(P<0.01),其中对TN的去除率较对照组提高了15.9%以上,对TP的去除率提高了34.1%以上.60%填充度和90%填充度的模块化人工湿地的TN、NO_(3)^(-)-N和TP去除率没有显著性差异(P>0.05),但NO_(3)^(-)-N和TP的去除效果比30%填充度的模块化人工湿地更好(P<0.05).MCW强化了脱氮除磷效果,特别是60%填充度模块化人工湿地因其较低成本而具有广阔的应用价值.

In this paper,a novel modular constructed wetland(MCW)based on a mixture of organic and inorganic substrates was employed for the tertiary treatment of the tail water from sewage treatment plant.The MCW was composed of two-stage units in series,and filled with ceramsite,biochar and gravel,in which the ceramsite in the first stage unit was in three groups according to 90%,60%and 30%pre volume,the second stage unit was filled with ceramsite of the same volume as the first stage,and the remaining volume was filled with biochar.The results showed that the removal efficiencies of TN,NO_(3)^(-)-N and TP in the three sets were significantly higher than the control group(P<0.01).Compared with the control group,the TN removal efficiencies in the three sets increased by more than 15.9%,the removal efficiencies of TP increased by more than 34.1%.There was no significant difference in the removal efficiencies of TN,NO_(3)^(-)-N and TP of the MCW with 60%and 90%substrate filling factors(P>0.05),but they had significant higher removal efficiencies of NO_(3)^(-)-N and TP than those of the 30%one(P<0.05).The novel MCW enhanced the effect of nitrogen and phosphorus removal,especially the MCW with 60%substrate filling factor owned great application value due to its lower cost.