Experimental and Theoretical Investigations of Fundamental Processes Relevant to Chemical Oxidation of Dense Nonaqueous Phase Liquids in Fractured Rock

项目摘要/摘要本研究的目的是进行实验，计算和理论研究的基本过程中涉及的氧化还原反应在破碎的岩石系统，包括自然氧化还原过程和相关的环境修复过程。 我们将专注于断裂内截留的不动流体相的氧化，以及氧化剂通过基质扩散进入岩石基质内的溶解物质/固体矿物相的氧化。 反应产物对介质改变的影响，以及对流动和传输特性的相关反馈也将被量化。 裂缝内自由相NAPL的氧化实验将在劳伦斯利弗莫尔国家实验室与Russell Detwiler博士合作进行，在一个非侵入性实验系统中，可以进行高分辨率的定量测量，同时可视化氧化的复杂后果，包括MnO 2的产生和运输。 将在科罗拉多大学进行岩石基质中溶解的NAPL化学氧化的实验研究和计算/理论建模，以研究氧化前沿通过扩散进入岩石基质的运动以及断裂-基质相互作用在岩石中的作用。氧化剂的运输。 “反应前沿扩散率”的概念和浓度分布的自相似解决方案将被追求发展的理论理解的反应扩散前沿，和三维模拟将被追求，以评估矩阵异质性的后果。 将在受控的实验室实验中研究岩石-基质相互作用对氧化剂迁移的影响，并将开发计算模型来预测复杂裂隙岩体中氧化还原过程的行为。 更广泛的影响：教育活动将涉及协同作用与内部赠款（25,000美元，P.I.）。Rajaram）来自科罗拉多大学（CU）的工程卓越基金。这笔赠款的目的是使多孔介质教育实验室现代化，通过增加反应运输部分，其范围将大大扩大。 私家侦探的部门主办的REU网站在环境工程，通过本科生将被招募参加这项研究。 在该项目的后期阶段，将建立一个专门讨论断裂岩体中氧化还原反应的教育网站，包括有关文献目录、说明基本过程的基本教程、实验结果动画和可免费下载的简单计算机代码。 我们还将与专注于在破碎岩石场地应用氧化技术进行修复或水质评估的咨询公司发展协同效应。

Project Summary/Abstract The objective of this research is to carry out experimental, computational and theoretical investigations of fundamental processes involved in oxidation-reduction reactions in fractured rock systems, encompassing natural redox processes and processes relevant to environmental remediation. We will focus on oxidation of an entrapped immobile fluid phase within fractures, and oxidation of dissolved species/solid mineral phases within the rock matrix that are accessed by the oxidant via matrix diffusion. The influence of the reaction products on medium alteration, and associated feedback on flow and transport properties will also be quantified. Experiments on oxidation of free-phase NAPL within fractures will be carried out at Lawrence Livermore National Laboratory in collaboration with Dr. Russell Detwiler, in a non-intrusive experimental system where high-resolution quantitative measurements can be performed while visualizing the complex consequences of oxidation, including MnO2 generation and transport. Experimental studies and computational/theoretical modeling of chemical oxidation of dissolved NAPLs in the rock matrix will be carried out at the University of Colorado to investigate the movement of an oxidation front into a rock matrix by diffusion and the role of fracture-matrix interactions in the transport of oxidant. The concept of "reaction front diffusivity" and self-similar solutions for the concentration profiles will be pursued to develop theoretical understanding of reaction-diffusion fronts, and three-dimensional simulations will be pursued to evaluate the consequences of matrix heterogeneity. The influence of fracture-matrix interactions on oxidant transport will be investigated in controlled laboratory experiments and computational models will be developed to predict behavior of oxidation-reduction processes in complex fractured rock masses. Broader Impacts: Educational activities will involve synergy with an internal grant ($25,000, P.I. Rajaram) from the Engineering Excellence Fund at the University of Colorado (CU). The objective of this grant is to modernize the educational laboratories for porous media, and its scope will be greatly enhanced by adding a reactive transport component. The P.I.'s Department hosts a REU site in environmental engineering, through which undergraduate students will be recruited to participate in this research. An educational web site devoted to oxidation-reduction reactions in fractured rock masses will be developed in the later stages of the project, including a bibliography of relevant literature, basic tutorials illustrating fundamental processes, animations of experimental results and simple computer codes that may be downloaded freely. We will also develop synergy with consulting companies focused on applying oxidation technologies in fractured rock sites for remediation or water quality assessment.