【作者】 黄娟；

【导师】 王世和；

【作者基本信息】 东南大学 ， 环境工程， 2004， 硕士

【摘要】 人工湿地是一项水质净化效果好,建造、运行费用低的生态污水处理技术,日益受到重视。但由于目前尚缺少对湿地净化机理的系统研究,人工湿地技术的应用多依据实践经验,影响了该技术的进一步发展。本文研究了种有多种植物的水平推流式潜流湿地和垂直流芦苇湿地处理污水厂初沉池出水的运行特性,通过一年多的试验研究,较全面地掌握了其净化功能和相关影响因素,在此基础上,确定了本人工湿地的最佳运行工况条件,并初步探讨了人工湿地污水处理系统中氮转移规律和去除机理。研究结果表明,种有各种植物的水平推流湿地对污水的净化效果较为稳定,当平均温度为20oC左右并处于最佳水力条件,即停留时间5.5d、出水水位60cm时,水平流芦苇湿地对CODCr、TN、TP的去除率分别达到73.1%、61.2%、52.2%左右。通过对各湿地净化效果的比较,在相同的试验条件下,种有各种植物的水平推流湿地对污染物的净化效果均优于空白湿地,但次于垂直流湿地,其中芦苇、美人蕉湿地脱氮效果显著,茶花湿地越冬性能好。植物选择以及生长周期的管理会影响湿地的运行稳定性能,植物光合作用与湿地脱氮效果存在显著相关,可作为湿地植物优选的一个重要指标之一。通过对湿地脱氮系统的研究发现,潜流式人工湿地氨氮挥发量仅占总氮去除率的0.5%以下,而湿地基质仅为微生物降解和植物吸收提供中介作用,大部分总氮由微生物作用去除,微生物同化及降解起到了主导作用,此外,湿地植物在整个湿地脱氮系统中也起到不可忽视的推动作用。试验证明人工湿地技术在污水处理方面具有一定的实际应用价值,在经济上和技术上均具有优势。更多还原

【Abstract】 The constructed wetland is an ecological sewage treatment with good removal effects and low construction and operation cost. However, for the lack of systematical study on purificatory mechanism of wetlands, constructed wetlands technology is applied mainly depending on experience. As a result, its further development is disturbed to some extent.In this paper, horizontal flow wetlands with various kinds of plants grown and vertical flow wetlands with reeds planted are first studied on their operation characteristics in treating the sewage out from the primary sedimentary basin. After more than one year’s experimental research, purificatory function and relevant factors of wetlands are comprehensively grasped. Based on it, the optimal operation condition is then determined. Finally, the nitrogen transferring rules and removing mechanism in sewage treatment system of wetlands is fundamentally discussed.Researches show that horizontal flow wetlands with plants grown have steadier removal effects. When average temperature is 20 degrees centigrade and the optimal hydraulic condition is reached (i.e. HRT 5.5 hours and out-waterline 60 centimeters), the removal percentage of CODCr, TN, TP in horizontal flow wetlands with reeds is respectively around 73.1%, 61.2%, 52.2%. By comparison of all kinds of wetlands under the same experimental condition, horizontal flow wetlands have better removal effects than blank ones, but inferior to vertical ones, among which wetlands with reeds and cannas have marked nitrogen removal effects and wetlands with camellias perform well through out the winter. Moreover, results are also obtained that plant selection and management of growing cycle affect the operational stability of wetlands and there exists a notable correlation between plants’photosynthesis and wetlands’nitrogen removal effects, which can be consider as a significant index for plant selection.By virtue of the study on nitrogen removal system in wetlands, it can be discovered that the amount of volatile nitrogen barely accounts for less than 0.5%, while substrata in wetlands only provides medi-action for microbial decomposing and vegetable assimilation, in which microbial assimilation and decomposing action dominate. Furthermore, plants in wetlands also play an important role in promoting the whole nitrogen removal system of wetlands.Finally, experiments demonstrate that the constructed wetland technology has a certain applicable value in sewage treatment and take an advantage in economic and technological aspects.更多还原