One-dimensional advection-diffusion model and analytical solution for inorganic contaminant ion transport in electro-kinetic barrier

被引：0
|
作者：
Huang P. [1 ]
Wang L. [1 ]
Liu S. [1 ]
Xue C. [1 ]
机构：
[1] College of Water Conservancy and Hydropower, Hohai University, Nanjing, 210098, Jiangsu
来源：
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | 2020年 / 39卷 / 08期
基金：
中国国家自然科学基金;
关键词：
Analytical solution; Contaminant migration; Electro-kinetic barrier; Foundation engineering; Parameter analysis;
D O I：
10.13722/j.cnki.jrme.2019.1226
中图分类号：
学科分类号：
摘要：
Electro-kinetic remediation is one soil remediation technology with a significant application prospect, and the electro-kinetic barrier developed based on the principle of this technology can effectively prevent the diffusion of contaminant ions to nearby soils or underground water. In this paper, a 1D advection-diffusion model for contaminant ion transport was established for the electro-kinetic barrier considering the combined action of concentration gradient, hydraulic gradient, electro-osmosis and electro-migration. Analytical solution was then derived by using the Laplace transform method, and the formula for calculating the mass flux was also given. Thereafter, the proposed analytical solution was verified by the 1D mode test results in the previous study. Finally, parameter study was conducted to analyze the migration of contaminant ions in the electro-kinetic barrier. The results indicate that the mass flux of Pb2+ at anode boundary decreases remarkably with increasing average potential gradient, barrier thickness or electro-osmotic conductivity. For the contaminant ions with a large diffusion coefficient, it is suggested to increase the potential gradient to improve the effect of electro-kinetic migration. The soil adsorption retardation coefficient has an unremarkable effect on the final stable outflow mass flux but can effectively prolong the breakthrough time of the electro-kinetic barrier. The proposed analytical solution can not only provide a simple calculation method for the design of electro-kinetic barrier but also be used to verify the corresponding numerical models. © 2020, Science Press. All right reserved.
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页码：1719 / 1728
页数：9
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