摘要
人工湿地污水处理技术具有经济、高效等特点,但其净化效率及稳定性存在较大差异。该文应用Meta分析方法,对我国境内构建的人工湿地对总固体悬浮物(TSS)、总氮(TN)、总磷(TP)、氨氮、生化需氧量(BOD)和化学需氧量(COD)等几种主要水质指标的去除率效应值进行了比较研究。结果表明:(1)人工湿地对不同水质指标去除率及其稳定性存在一定差异,对物理过程发挥重要作用的TSS、TP以及容易生物降解的BOD的去除率较高且相对稳定,而对相对复杂的化学和生物过程发挥重要作用的氨氮、COD和TN等指标的去除率相对较低,稳定性也相对较差;(2)单一类型湿地中,垂直潜流对TN、氨氮、BOD和COD去除率较高,水平潜流对TP去除率较高但对TN去除率较低,自由表流对TSS去除率较高但对TP、氨氮、BOD和COD去除率较低,复合湿地去除效果总体较好;(3)人工湿地对入流浓度高的水体去除率较高且稳定,随着污染浓度的提高,人工湿地对各类污染物去除率有上升的趋势。根据入流水质污染程度不同有针对性地设计复合人工湿地可有效利用各类湿地的相对处理优势及处理成本,达到最佳净化效果。
Constructed wetland is economy and efficiency for the protection of the water environment. However, there are great differences in the removal efficiency. Meta-analysis was applied in this paper to assess various wetlands purification ability to the main water quality indexes such as TSS, TN, TP, ammonia nitrogen, BOD and COD. The results show that there are some differences between water quality indexes of the removal rate and stability. The removal rates of TSS, BOD and TP are relatively high and stable in constructed wetlands, while the removal rates of ammonia nitrogen, COD and TN are relatively low and instable. Physical processes play a major role in the removal mechanism of TSS, BOD and TP, while chemical processes play a major role in the removal mechanism of ammonia nitrogen, COD and TN. Besides, in single type wetlands, the removal rates of TN, ammonia nitrogen, BOD and COD are relatively high in the vertical sub-surface constructed wetlands. Compared with TN removal rate, TP removal rate is relatively high in the horizontal sub-surface constructed wetlands. TSS removal rate is relatively high in the free water surface wetlands compared with the removal rates of TP, ammonia nitrogen, BOD and COD. Meanwhile, removal rates in hybrid constructed wetlands are generally better than single type wetlands. The comparison of the removal rates in different inflow conditions demonstrate that the removal rates of constructed wetlands are high and stable with high pollution of water inflow, the higher the concentration of pollutants is, the better the removal rates will be. Hybrid constructed wetland, which is designed according to different levels of water pollution, can take the advantage of various constructed wetlands and processing costs effectively to achieve the optimal purification efficiency.
出处
《净水技术》
CAS
2015年第6期30-36,共7页
Water Purification Technology
基金
国家水体污染控制与治理科技重大专项(2009ZX07318-001)
国家科技重大专项(2012ZX07204004
2012ZX07101013)
国家自然科学基金(41271197)
关键词
人工湿地
去除率
META分析
构造湿地类型
污染浓度
constructed wetland removal rate Meta-analysis wetland type pollution concentration
