石嘴山市大武口区生活垃圾填埋场地下水污染及预测研究

发布时间：2018-05-16 08:56

本文选题：垃圾填埋 + 水质评价　；参考：《长安大学》2015年硕士论文

【摘要】：垃圾渗滤液是一种成分复杂的高浓度有机废水,虽然大部分垃圾填埋场采取了防渗措施,但当防渗层达不到预期效果或破损失效时,垃圾渗滤液就会进入含水层,对地下水造成污染。且这种污染延续的时间可长达数十年,甚至上百年。地下水受到污染后,修复难度很大,将对人民群众的生活造成严重影响。因此,对垃圾填埋场及其周边地下水进行污染研究及预测,对防治地下水污染、保护影响区人民群众身体健康具有十分重要的意义。本文在充分研究区域地质、水文地质条件的基础上,通过资料收集、野外环境地质调查、水位动态监测、采样分析、水均衡计算、水质评价、健康风险评价、地下水数值模拟等方法,剖析了石嘴山市大武口区生活垃圾填埋场及其周边含水层的分布、结构及地下水的补给、径流、排泄条件以及地下水环境现状。以此为基础,应用Visual Modflow软件建立了研究区地下水流数值模型和MT3DMS溶质运移模型,在水流数值模型识别与验证较为理想的前提下,选择超标倍数最高的氨氮作为特征污染因子,对浅层地下水中氨氮的迁移规律、污染发展趋势进行了模拟预测,结果表明:氨氮在水平方向上主要向西北方向迁移扩散。若垃圾渗滤液以当前情况泄漏至18年后封场,则18年后氨氮污染晕中心点浓度最大将达到500mg/L,随后浓度逐渐下降,50年后中心点氨氮浓度下降至80mg/L;若采取措施有效阻止泄漏,18年后氨氮污染晕中心点浓度下降至80mg/L,50年后中心点氨氮浓度下降至25mg/L。总体来看研究区地势较为平缓,地下水运移速度较慢,当前污染晕还未扩散出场区,50年后,污染晕也只向外迁移扩散了490m,污染仍在可控范围内,对距垃圾填埋场较远的居民区用水影响不大。研究成果为大武口生活垃圾填埋场渗滤液泄漏治理、保护地下水资源提供了理论依据。
[Abstract]:Landfill leachate is a kind of high concentration organic wastewater with complex composition. Although most landfills take anti-seepage measures, when the impermeable layer fails to achieve the desired effect or fails, the landfill leachate will enter the aquifer. Pollute groundwater. And the pollution can last for decades, or even hundreds of years. After the groundwater is polluted, it is very difficult to repair, which will have a serious impact on the life of the people. Therefore, it is of great significance to study and forecast the pollution of landfill site and its surrounding groundwater to prevent and control the groundwater pollution and to protect the health of the people in the affected area. Based on the full study of regional geology and hydrogeological conditions, this paper, through data collection, field environmental geological investigation, water level dynamic monitoring, sampling analysis, water balance calculation, water quality evaluation, health risk assessment, The distribution, structure, groundwater recharge, runoff, discharge conditions and the present situation of groundwater environment of the landfill site and its surrounding aquifer in Dawukou District, Shizuishan City, are analyzed by numerical simulation of groundwater. Based on this, the numerical model of groundwater flow and MT3DMS solute transport model in the study area are established by using Visual Modflow software. On the premise of identifying and verifying the numerical model of water flow, the ammonia nitrogen with the highest ratio of exceeding the standard is selected as the characteristic pollution factor. The transport law of ammonia nitrogen in shallow groundwater and the trend of pollution development were simulated and predicted. The results showed that ammonia nitrogen mainly migrated and diffused northwestward in horizontal direction. If the landfill leachate leaks to 18 years after the current situation, After 18 years, the maximum concentration of ammonia nitrogen pollution halo center will reach 500 mg / L, then the concentration will decrease gradually, 50 years later, the ammonia nitrogen concentration will drop to 80 mg / L; if measures are taken to prevent the leakage effectively, the concentration of ammonia nitrogen pollution halo center point will drop to 80 mg / L ~ (50) after 18 years. The concentration of NH3-N at the central point decreased to 25 mg / L after a year. On the whole, the study area is relatively flat, the speed of groundwater movement is relatively slow, and the current pollution halo has not yet spread out. Fifty years later, the pollution halo has only migrated outward and spread 490 m, and the pollution is still under control. It has little effect on water use in residential areas far from landfill site. The research results provide theoretical basis for leachate leakage control and protection of groundwater resources in Dawukou municipal solid waste landfill.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X523;X799.3

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