Mobilization of Residual NAPL by Seismic Waves

项目摘要：通过地震波动员剩余的NAPL常规的泵和处理技术已被证明是无效的，在清理含水层被非水相液体（NAPL）污染。加强对受NAPL污染的含水层进行补救的一种可能办法是应用地震波。 然而，我们对导致动员的机制知之甚少，我们假设可以通过利用毛细作用诱导的共振来优化被捕获的NAPL斑点的动员。我们将进行实验，可视化多孔介质中的NAPL斑点的振荡流，这是地震波的一个组成部分的响应。 周围水相中的恒定背景流将确保移动的斑点移动到期望的方向，从而模拟泵送和处理与地震波的组合作用。 光学折射率匹配将允许对流动池中的流体进行不受干扰的观察。 用平面激光片和高速摄影的照明将解决激励周期内的运动。 团块将（1）以其共振频率被激发，以增强对过程的理解，以及（2）以适当参数化的频率扫描的形式被激发，以说明团块在移动通过孔隙空间时改变其共振频率的事实。 将开发一个格子玻尔兹曼（LB）模型，用于指导实验的设计，并作为一个模拟试验台。还将测量和评估界面激发期间形成小的、移动的液滴的重要性。从物理实验和LB simulation.Our研究可以提高地下水修复技术的效率NAPL污染和提高石油采收率计划，使用地震波的共振频率的相关性被困的斑点和强度，以动员他们将推断。我们将从总体上阐明振荡流如何影响多孔介质中不混溶流体的分布。该研究也将有助于理解振荡流对不混溶流体之间传质（溶解）的影响。此外，NAPL斑点共振可用于监测地下水修复过程中NAPL池的收缩，甚至定位NAPL池。该项目将为一名博士生提供研究机会。 此外，该项目将丰富巴尔的摩市社区学校的K-12教育。 博士生将开发一个关于地下水污染的教学模块。

Project Abstract: Mobilization of Residual NAPL by Seismic WavesConventional pump-and-treat technologies have proven to be ineffective in cleaning up aquifers that are contaminated by nonaqueous phase liquids (NAPL). One possible approach for enhancing the remediation of NAPL-contaminated aquifers consists of applying seismic waves. Little is known, however, about the mechanism leading to mobilization.We hypothesize that the mobilization of trapped NAPL blobs can be optimized by exploiting capillarity-induced resonance. We will perform experiments that visualize the response of NAPL blobs in porous media to oscillatory flow, which is one component of a seismic wave. Constant background flow in the surrounding aqueous phase will ensure that mobilized blobs are moved into a desired direction and hence simulate the combined action of pump-and-treat and seismic waves. Optical refractive index matching will allow for undisturbed view on the fluids in the flow cells. Illumination with a planar laser sheet and high speed photography will resolve the motion within an excitation cycle. Blobs will be excited (1) at their resonant frequency to enhance process understanding, and (2) in the form of appropriately parameterized frequency sweeps to account for the facts that a blob changes its resonant frequency as it moves through a pore space. A lattice-Boltzmann (LB) model will be developed that is used to guide the design of the experiments and as a simulation test bed. The importance of the formation of small, mobile droplets during excitation of the interfaces will also be measured and evaluated. Correlations for the resonant frequency of trapped blobs and intensities required to mobilize them will be inferred from physical experiments and LB simulations.Our research could improve the efficiency of both groundwater remediation techniques for NAPL contamination and enhanced oil recovery schemes that use seismic waves. We will in general elucidate how oscillatory flows effect the distribution of immiscible fluids in porous media. The proposed research will also help understanding the effects of oscillatory flow on mass transfer (dissolution) between immiscible fluids. Furthermore, NAPL blob resonance could be exploited to monitor the shrinking of a NAPL pool during a groundwater remediation, or even to locate NAPL pools. The project will provide research opportunities for one PhD student. Moreover, the project will enrich K-12 education at Baltimore City Neighborhood Schools. The PhD student will develop a teaching module on groundwater contamination.