【作者】 肖婷；

【导师】 马放； 王立；

【作者基本信息】 哈尔滨工业大学 ， 环境工程， 2010， 硕士

【摘要】 随着我国经济的发展和城镇化进程的加快,小城镇人口不断集中,其污水排放量也不断增加,村镇水污染问题日益加剧,严重影响了我国的水环境。人工湿地处理技术与传统技术相比具有投资、运行费用低、管理要求低,处理效率高等优点,适合处理小城镇生活污水和农村面源污染。但是北方寒冷地区采用传统的人工湿地污水处理技术存在着难以越冬的问题,影响了其在北方地区的应用。基于东北气候寒冷的特点,选择天然土壤、沸石、炉渣等除污效果好、廉价易得的填料,通过构建不同基质以及基质配比的垂直潜流生物滤床,对解决人工湿地在北方地区冬季运行的问题进行探讨,探求低温对不同类型填料床的处理效果的影响程度以及系统的除污机理,旨在为北方地区寒冷气候下应用湿地技术提供有利的技术支持。采用静态实验对填料的吸附性能进行研究,其中包括吸附动力学和等温吸附特性的研究,对实验结果进行数据拟合,得出理论饱和吸附量、平衡时间、吸附稳定性等指示性指标,对填料的吸附性能进行评价,并对填料的吸附原理进行探讨。构建尺寸为35cm×25cm×20cm的垂直潜流填料床,模拟人工湿地在冬季无植物情况下的运行状态,分别于室温和室外低温条件下运行,考察反应器运行期间对浊度、有机物、氮磷等污染物的去除效能,对比不同填料、以及不同温度条件下各填料床除污能力的差异,并对反映反应器特性的指标如溶解氧、pH值、氧化还原电位、微生物指标等进行分析。研究结果表明,沸石对氨氮有良好的吸附能力,天然土、炉渣对氮、磷均有较好的吸附作用;沸石、炉渣、沸石/炉渣混合填料床对生活污水有良好的净化能力,其中沸石床脱氮效果较好,对总氮的平均去除率为82.7%,且低温下也能保持对氮素良好的去除效果;炉渣床除磷、降解有机物效果较好,对总磷和TOC的平均去除率分别为94.1%、80.8%;低温下填料床对有机物的去除率有所下降,而氨氮、磷、悬浮物的去除率受温度影响较小,炉渣床和混合床在低温下对总氮的去除率下降;反应器内有大量微生物累积,总体而言,土壤表层微生物量和生物活性均高于下层填料,反应器内微生物活性可在一定程度上揭示其除污机理。更多还原

【Abstract】 With the development of economy and accelerated urbanization process of China, population of villages and towns increases remarkably, which makes the increasing discharge of wastewater. It is a growing problem which impacts the whole fresh water environment of China. Constructed wetland treatment technology needs low investments, low operating costs, low level of regulatory requirements, and high treat efficiency, compared to traditional technology. So, constructed wetlands (CWs) are suitable for domestic sewage of small towns and non-point pollutions of rural areas. However, under the cold climate of northern regions, constructed wetlands show low efficiency in winter, which impacts the application of them in Northern China.Based on the characteristic of Northeastern China, we choose decontamination effective, cheap and easy-getting materials such as natural soil, zeolite and slag as substrates of constructed wetlands. We construct vertical-subsurface flow biological filter bed, with different substrates/substrate ratio filled; discuss the solution of the operation of CWs in winters in north areas, aiming at providing sound technique support for its application.We choose static experiments for the research on adsorption properties of the fillers, focusing on adsorption kinetics and isotherm. We fit the data of the experimental results; conclude some indicative index such as their adsorption capacity, equilibrium time and adsorption stability; evaluate the fillers’adsorption performance, and discuss their adsorption principles. We also structure six vertical sub-surface flow filter beds, whose sizes are all 35cm×25cm×20cm, aim to simulate the performance of CWs without plants in winter. The ratio of fillers is gravel 5cm, the main filler 10cm, and natural soil 5cm. The condition of running are: operation cycle is 24h, including inflow, 8h stay and outflow, 16h stay, hydraulic loading is 0.114m3/ (m3·d). The changes of main pollution index of water are considered, comparing the decontamination capability of different filter beds and under different temperatures. We also make analysis on microbial indicators, in order to explore the purification mechanism of the system.The experimental results show: zeolite indicates fine capacity on ammonia adsorption; natural soil and slag have good adsorption on phosphorus and nitrogen. Beds with zeolite, slag, and zeolite/slag mixed packed all show good purification capacity for domestic sewage. Among these three kind of filter beds, zeolite bed shows better performance of nitrogen removal, with average removal rate 82.7%, and under low temporary, its efficiency is high for total nitrogen; and slag bed shows better capacity of decontamination of phosphorus and organic matter, the removal rates of whom are 94.1% and 80.8%, respectively. Removal capability for organic compounds is impacted under low temperatures, while nitrogen, phosphorus and suspended solids removal rates are less affected by temperature. There are a large number of microorganisms accumulating in the reactors. Microbial biomass and biological activity are significant higher in the surface soil than in the lower filler layer; and the biological index could indicate the mechanism of decontamination of wastewater to a certain extent.更多还原