Zero-valent iron (ZVI) permeable reactive barrier (PRB) is a treatment wall filled with ZVI as a reactive material that is installed perpendicular to the groundwater flow in the subsurface. To aid design of these PRBs, a non-dimensional analysis of the permeability reduction has been carried out in this work where the dimensionless equation has been identified to correlate different variables. Additionally, the change in physical features of ZVI PRB has been identified using the inspection system of x-ray microcomputer tomography (μCT) and it has shown that the particle size is expanding, thus reducing the permeability. The change in chemical composition that impact the surface reactivity has been confirmed using x-ray diffraction (XRD) and the corroded products of maghemite and magnetite have been identified. Flow experiments have been conducted to observe and measure the changes in permeability, where the pressure at various points of the experimental rigs has been measured for the calculation of permeability values. The reduction in permeability could be observed from both small and large scale experiments. For example, the flow experiments indicated that the permeability value has been significantly reduced for coarse particle, e.g., in small scale experiment, it reduced from 7.04E-8 to 3.09E-9 cm2. It can also be seen that the permeability is decreased by 95.6% for small scale (coarse particle) and by 79.5% for large scale.
Funding
This study was carried out with the funds from Ministry of Science and Technology of Thailand and Department of Chemical Engineering, Loughborough University, UK.
History
School
Aeronautical, Automotive, Chemical and Materials Engineering
Department
Chemical Engineering
Published in
Transport in Porous Media
Citation
SANTISUKKASAEM, U. and DAS, D.B., 2018. A non-dimensional analysis of permeability loss in zero-valent iron permeable reactive barrier (PRB). Transport in Porous Media, 126 (1), pp.139–159.
This work is made available according to the conditions of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) licence. Full details of this licence are available at: https://creativecommons.org/licenses/by-nc-nd/4.0/
Acceptance date
2018-05-27
Publication date
2018-06-15
Notes
This is a post-peer-review, pre-copyedit version of an article published in Transport in Porous Media. The final authenticated version is available online at: https://doi.org/10.1007/s11242-018-1096-0