Mobilization of Residual NAPL by Seismic Waves

地震波对残余 NAPL 的动员

• 批准号: 0739038
• 负责人: Markus Hilpert
• 金额: $ 21.53万
• 依托单位: Johns Hopkins University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-03-01 至 2011-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0739038&HistoricalAwards=false
• 关键词: Mobilization; Residual; NAPL; Seismic; Waves

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.

项目摘要：通过地震波动员残余 NAPL 传统的泵处理技术已被证明无法有效清理被非水相液体 (NAPL) 污染的含水层。加强受 NAPL 污染的含水层修复的一种可能方法是应用地震波。 然而，关于导致动员的机制知之甚少。我们假设可以通过利用毛细管现象引起的共振来优化被捕获的 NAPL 斑点的动员。我们将进行实验，将多孔介质中的 NAPL 斑点对振荡流（地震波的组成部分之一）的响应进行可视化。 周围水相中恒定的背景流将确保流动的斑点移动到所需的方向，从而模拟泵处理和地震波的联合作用。 光学折射率匹配将允许不受干扰地观察流通池中的流体。 使用平面激光片和高速摄影进行照明将解析激发周期内的运动。 斑点将被激发（1）以其共振频率来增强过程理解，以及（2）以适当参数化的频率扫描的形式来解释斑点在穿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，用于指导实验设计并作为模拟测试台。还将测量和评估在界面激发过程中形成小的、可移动的液滴的重要性。被捕获的斑点的共振频率和动员它们所需的强度的相关性将从物理实验和LB模拟中推断出来。我们的研究可以提高NAPL污染地下水修复技术和使用地震波的提高石油采收率方案的效率。我们将一般性地阐明振荡流如何影响多孔介质中不混溶流体的分布。拟议的研究还将有助于了解振荡流对不混溶流体之间的质量传递（溶解）的影响。此外，NAPL 斑点共振可用于监测地下水修复期间 NAPL 池的收缩情况，甚至可以定位 NAPL 池。该项目将为一名博士生提供研究机会。 此外，该项目还将丰富巴尔的摩市邻里学校的 K-12 教育。 博士生将开发一个有关地下水污染的教学模块。