潜流—表流复合人工湿地处理超低TN含量废水

Study on Treatment of Ultra-Low TN-contaminated Wastewater by Composite Constructed Wetland with Subsurface and Surface Flow

为了解基质粒径以及植物种类对复合人工湿地处理超低TN含量废水净化效果,研究了4组复合人工湿地的出水效果及与微生物群落的关系。结果表明,4组复合人工湿地对NH3-N、TN和TP的总去除率为66.54%~74.05%、61.55%~73.61%、38.16%~54.64%,均有较好的处理效果。脱氮除磷主要发生在潜流湿地,去除率最高的为A1组风车草。人工湿地中主要的反硝化细菌是不动杆菌属、假单胞菌属、芽孢杆菌属,主要的除磷细菌是不动杆菌属、假单胞菌属。5~20 mm粒径基质不动杆菌属、假单胞菌属、芽孢杆菌属的丰度增加,提高了脱氮除磷的效果。风车草的种植改善了基质微生物的多样性和丰度,该组的不动杆菌属、假单胞菌属、芽孢杆菌属明显高于梭鱼草组,这是风车草组处理效果优于梭鱼草组的原因。

In order to investigate the effects of particle size of the substrate and vegetation species on the purification efficiency of ultra-low TN-contaminated wastewater by composite constructed wetland(CWs),the relationship between purification effects and microbial community in four groups CWs were researched.The results showed that,four groups of CWs had a good treatment effect on NH3-N(66.54%~74.05%),TN(61.55%~73.61%)and TP(38.16%~54.64%).Moreover,nitrogen and phosphorus removal mainly occurred in subsurface flow wetlands,especially for A1 group(Cyperus alternifolius L).achieved the highest removal rate of nitrogen and phosphorus.The Pseudomonas,Acinetobacter,Bacillus were the main genus of denitrifying bacteria,as well as Pseudomonas,Acinetobacter were the main genus of dephosphorization.The abundance of Pseudomonas,Acinetobacter,Bacillus with particle size of 5~20 mm increased,which improved the effect of nitrogen and phosphorus removal.The cultivation of Cyperus alternifolius L improved the diversity and abundance of bacteria in substrate.In addition,the abundance of Pseudomonas,Acinetobacter,Bacillus in group of Cyperus alternifolius L was significantly higher than group of Pontederia cordata L,which was the reason why the treatment effect of group of Cyperus alternifolius L was better than group of Pontederia cordata L.