Original scientific paper
https://doi.org/10.17794/rgn.2021.5.6
SIMULATION OF AQUIFER REMEDIATION FROM LOW-PERMEABLE LENSES BY BACK-DIFFUSION PHENOMENON
Mojtaba Dehqani Tafti
; Shahrood University of Technology, Faculty of Mining, Petroleum and Geophysics Engineering, Shahrood, Iran
Faramarz Doulati Ardejani
; School of Mining, College of Engineering, University of Tehran, Tehran, Iran
Mohammad Fatehi Marji
; Department of Mining and Metallurgical Engineering, Yazd University, Yazd, Iran
Yousef Shiri
; Shahrood University of Technology, Faculty of Mining, Petroleum and Geophysics Engineering, Shahrood, Iran
Abstract
Fluid flow in a dual permeable medium (DPM) is essential in solute transport in mining and aquifer studies. In this paper, water flushing into a contaminated DPM containing fine-grained lenses with different geometries was investigated with the Lattice Boltzmann Method (LBM). The LBM model used in this study was D2Q9 with a relaxation time of 1, a cohesion value of 3 for a fluid density of 1 (mu.Lu-3). The saturated fluid in the DPM was a contaminant that usually stays in low permeable lenses and after flushing, it is leaked into the porous medium by a second fluid (water). This phenomenon is predominant when the displacing fluid has a lower concentration than the contaminated fluid. Diffusion and advection are the main mechanisms that control fluid flow in the porous medium. The results of the simulations showed: (1) advection controlled solute transport through the flushing phase, and back-diffusion occurred after the change in phase; (2) the lenses’ geometry influenced the fluid flow pattern and the remediation process. As a result, aquifer remediation strategies based on the lenses’ geometry and their permeability can help us select the appropriate environmental protection.
Keywords
Lattice Boltzmann Method (LBM); contamination back-diffusion; low-permeable lenses; aquifer remediation; dual permeable medium (DPM)
Hrčak ID:
266325
URI
Publication date:
24.11.2021.
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