Study of transport and dissolution of a nonaqueous phase liquid in porous media: effects of low-frequency pulsations and surfactants

Date
2001-01-01
Authors
Fontenot, Mirrya
Major Professor
Advisor
R. Dennis Vigil
Committee Member
Journal Title
Journal ISSN
Volume Title
Publisher
Altmetrics
Authors
Research Projects
Organizational Units
Journal Issue
Series
Department
Chemical and Biological Engineering
Abstract

The transport and dissolution of residual non aqueous phase liquids (NAPLs) trapped in water saturated porous media is a problem pertinent to both environmental and petrochemical industries. In this work we have quantitatively examined the complete dissolution of residual entrapped NAPL at the pore-scale in three dimensions using refractive index matching techniques along with planar laser induced fluorescence. The results yielded pore-scale information regarding ganglia volume, surface area, and position over time at various Capillary numbers. We found that with increasing Capillary numbers, the time for total dissolution decreased. In addition, it appears that large ganglia exhibit fractal area to volume scaling. We were also able to examine the distributions of the ganglia in the direction of flow over time.;The use of low-frequency flow pulsations as a removal technique was also examined. A two dimensional micromodel was used for these studies. We found that for this system, lower frequencies and higher amplitudes were more effective in NAPL removal due to breakup and mobilization. We also examined the effect of increasing amplitude and continuous versus pulsed stimulation. In addition, mass transport in the presence of a surfactant was also enhanced due to flow pulsation with lower frequencies and higher amplitudes again being most effective.

Comments
Description
Keywords
Citation
Source