微曝气强化人工湿地处理生活污水试验研究

The effects of domestic wastewater treatment by micro-aerated hybrid constructed wetland

传统人工湿地的自然复氧速率较低,对N、P营养元素的去除效率普遍不高。设计开发了一种微曝气系统,以期强化人工湿地对生活污水中C、N和P的去除。通过改变曝气量(气水比)以及在不同气温条件下检测该人工湿地处理生活污水效果,详细分析了经微曝气系统强化后的人工湿地对COD、TP以及各氮素污染物在系统的沿程去除情况。结果表明,微曝气系统能显著增强湿地对生活污水的处理效果。随着气水比由0∶1升高至4∶1,该湿地系统对污水中的COD和TP的去除率分别从约80%和60%提高到约93%和79%,而在3∶1时TN的去除率达到最高水平75%。低温对系统除碳脱氮影响较大,COD及TN去除率分别降低了约7%和8%。湿地污染物浓度沿程变化状况显示,污染物的去除过程主要发生在第2湿地系统。

The traditional constructed wetland is considered to have a low natural oxygen enrichment rate and low removal efficiency of N and P nutrients.Therefore,a micro-aerated constructed wetland was designed and developed to enhance the removal of C,N and P from domestic sewage in constructed wetlands.By changing the aeration amount(gas-water ratio)and detecting the effect of the constructed wetland on domestic sewage treatment under different temperature conditions,the COD,TP and various nitrogen pollutants along the system in the artificial wetland enhanced by the micro-aeration system were analyzed in detail.The results show that the micro-aeration system can significantly enhance the treatment effect of wetland on domestic sewage.With the gas-water ratio rising from 0:1 to 4:1,the COD and TP removal rate in the wetland increased from80%and 60%to 93%and 79%.TN removal rate decreased after reaching the top of 75%at gas-water ratio of 3:1 condition.The low temperature also shows a great impact on the removal of carbon and nitrogen.Compared with high temperature,the remove rate of COD and TN decreased by 7%and8%in the low temperature.The change of pollutantconcentration along the wetland shows that the removal process of pollutants mainly occurs in the second wetland system.