Comparison of theory and experiment for NAPL dissolution in porous media

Contamination of groundwater resources by an immiscible organic phase commonly called NAPL (Non Aqueous Phase Liquid) represents a major scientific challenge considering the residence time of such a pollutant. This contamination leads to the formation of NAPL blobs trapped in the soil and impact of...

Full description

Saved in:
Bibliographic Details
Published in:Journal of contaminant hydrology 2018-04, Vol.211, p.49-64
Main Authors: Bahar, T., Golfier, F., Oltéan, C., Lefevre, E., Lorgeoux, C.
Format: Article
Language:English
Subjects:
Earth Sciences
Engineering Sciences
Fluids mechanics
Groundwater - analysis
Groundwater - chemistry
Hydrocarbons - analysis
Hydrocarbons - chemistry
Hydrology
Hydrology - methods
Mechanics
Models, Theoretical
NAPL dissolution
Porosity
Porous media
Reactive fluid environment
Sciences of the Universe
Soil - chemistry
Solubility
Toluene - analysis
Toluene - chemistry
Upscaling
Volume averaging method
Water Pollutants, Chemical - analysis
Water Pollutants, Chemical - chemistry
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Contamination of groundwater resources by an immiscible organic phase commonly called NAPL (Non Aqueous Phase Liquid) represents a major scientific challenge considering the residence time of such a pollutant. This contamination leads to the formation of NAPL blobs trapped in the soil and impact of this residual saturation cannot be ignored for correct predictions of the contaminant fate. In this paper, we present results of micromodel experiments on the dissolution of pure hydrocarbon phase (toluene). They were conducted for two values of the Péclet number. These experiments provide data for comparison and validation of a two-phase non-equilibrium theoretical model developed by Quintard and Whitaker (1994) using the volume averaging method. The model was directly upscaled from the averaged pore-scale mass balance equations. The effective properties of the macroscopic model were calculated over periodic unit cells designed from images of the experimental flow cell. Comparison of experimental and numerical results shows that the transport model predicts correctly - with no fitting parameters - the main mechanisms of NAPL mass transfer. The study highlights the crucial need of having a fair recovery of pore-scale characteristic lengths to predict the mass transfer coefficient with accuracy.
ISSN:0169-7722
1873-6009
DOI:10.1016/j.jconhyd.2018.03.004