非均质含水层中有机污染物迁移机理研究

Dynamics of transport, transformation and fate and remediation technology of organic contaminants in groundwater are hot topic problems about groundwater pollution control. This research will select the lower Liaohe river basin as a research base. We will carry on transport mechanism of organic contaminants in groundwater by using site investigation, and site test, and indoor test, and physical simulation and mathematics simulation.BTEX and PCE are as two typical organic contaminants in groundwater. BTEX is an acronym that stands for benzene, toluene, ethylbenzene, and xylenes. These compounds are some of the volatile organic compounds (VOCs) found in petroleum derivatives such as petrol (gasoline). Toluene, ethylbenzene, and xylenes have harmful effects on the central nervous system. BTEX compounds are notorious due to the contamination of soil and groundwater with these compounds. BTEX is non-aqueous phase liquid light (LNAPLs) and PCE is non-aqueous phase liquid (DNAPLs). In Lab, we will set up sandy column, with high resolution X-ray and NMR scan technology, will observe and investigate transport processes of two species organic contaminants in heterogeneous porous media in pore scale and Darcy scale. Meanwhile we will set uo large sandy box within setting sand ans clay forming heterogeneous aquifer. We will observe and investigate transport processes of BTEX and PCE in large sandy box. Based on the Lab test, we will understand and open out the transport mechanism of organic contaminants in heterogeneous aquifer in different scales. Based test observation and theory analysis,the fractal geometry model and stochastical model for different scales transformation of organic contaminant transport will be proposed. Through test date analysis and theroy research, we will construct transport model of organic contaminants in heterogeneous aquifer. The proposed model will be applied to field investigation and validation. Using the model analyzes transport process of organic pollutants in the lower Liaohe River area. The foudings of this project will be used for prevention, control ,management and remediation of groundwater pollution.

有机污染物在地下水中的迁移、转化和归趋的动力学机制及其修复技术，是地下水污染防治的热点。本研究以下辽河地区地下水污染为研究基地，采用现场调查、现场试验、室内试验、物理模拟和数学模拟等研究手段，对单环芳香烃（BTEX）和四氯乙烯PCE两种典型有机物在非均质含水层中的迁移、转化和归趋过程、机理及动力学机理进行深入研究。BTEX为非水溶相轻液（LNAPLs），PCE为非水溶相重液（DNAPLs）。在室内非均质砂柱试验，借助高精度X射线和NMR扫描技术，在孔隙尺度和达西尺度观测有机物的迁移过程；在大型渗流槽内随机加入粘性土和砂混合，形成非均质介质，模拟BTEX和PCE在非均质含水层中的迁移转化过程，揭示其迁移机理；建立尺度转换的分形几何和随机关系式以及有机物在非均质含水层中迁移确定-随机性数学模型；将建立的模型用于下辽河地区有机污染物迁移转化分析以及污染源的解析。指导地下水污染防治。

有机污染物在非均质含水层中的迁移、转化和归趋的动力学机制及其修复技术，是地下水污染防治的热点。本研究以下辽河地区地下水污染为研究基地，采用现场调查、现场试验、室内试验、物理模拟和数学模拟等研究手段，对LNAPLs和DNAPLs 两种典型有机物在非均质含水层中的迁移、转化和归趋过程、机理及动力学机理进行深入研究。通过室内非均质砂柱试验、渗流槽试验和野外研究，获得如下研究成果：（1）揭示了MTBE在层状非均质含水层中的迁移规律，MTBE在层状含水层中符合非菲克定律；（2）建立了各种非均质含水层中吸附-反应（非反应）迁移的随机模型，并应用于下辽河地区；（3）研究了非均质含水层有机污染物的去除机理，如：耦合零价铁和生物炭系统降解非均质含水层中氯苯；将微生物固定在高密度丝瓜络上，并组合零价铁降解非均质含水层中三氯乙烷，提出了降解路径和反应机理。这些研究对于非均质含水层中有机污染物迁移机理、去除机理和数值模拟分析，具有重要的科学和应用价值。