An experimental study of complete dissolution of a nonaqueous phase liquid in saturated porous media

Imhoff, Paul T.; Jaffé, Peter R.; Pinder, George F.

doi:10.1029/93wr02675

Cited by 325 publications

(265 citation statements)

References 18 publications

Supporting

Mentioning

217

Contrasting

Unclassified

Order By: Relevance

“…Thus, a 2.5-cm diameter by 15-cm long column packed homogeneously with the 724-μm diameter sand was used for the control experiment. A residual saturation of trichloroethene was established throughout the column using standard procedures (e.g., Imhoff et al, 1994;Powers et al, 1994;Johnson et al, 2003).…”

Section: Methodsmentioning

confidence: 99%

Mass-removal and mass-flux-reduction behavior for idealized source zones with hydraulically poorly-accessible immiscible liquid

et al. 2008

View full text Add to dashboard Cite

A series of flow-cell experiments was conducted to investigate aqueous dissolution and massremoval behavior for systems wherein immiscible liquid was non-uniformly distributed in physically heterogeneous source zones. The study focused specifically on characterizing the relationship between mass flux reduction and mass removal for systems for which immiscible liquid is poorly accessible to flowing water. Two idealized scenarios were examined, one wherein immiscible liquid at residual saturation exists within a lower-permeability unit that resides in a higher-permeability matrix, and one wherein immiscible liquid at higher saturation (a pool) exists within a higherpermeability unit adjacent to a lower-permeability unit. The results showed that significant reductions in mass flux occurred at relatively moderate mass-removal fractions for all systems. Conversely, minimal mass flux reduction occurred until a relatively large fraction of mass (>80%) was removed for the control experiment, which was designed to exhibit ideal mass removal. In general, mass flux reduction was observed to follow an approximately one-to-one relationship with mass removal. Two methods for estimating mass-flux-reduction/mass-removal behavior, one based on system-indicator parameters (ganglia-to-pool ratio) and the other a simple mass-removal function, were used to evaluate the measured data. The results of this study illustrate the impact of poorly accessible immiscible liquid on mass-removal and mass-flux processes, and the difficulties posed for estimating mass-flux-reduction/mass-removal behavior.

show abstract

Section: Methodsmentioning

confidence: 99%

Mass-removal and mass-flux-reduction behavior for idealized source zones with hydraulically poorly-accessible immiscible liquid

et al. 2008

View full text Add to dashboard Cite

show abstract

“…Tomographic and optical techniques can provide additional experimental information about flow field dynamic in porous beds. Tomographic techniques include Magnetic Resonance Imaging (MRI) (Baldwin et al 1996;Sederman et al 1998;Ogawa et al 2001;Suekane et al 2003), Emission Tomography (PET) (Khalili et al 1998), NMR imaging (Baldwin et al 1996;Johns and Gladden 1999), gamma attenuation (Imhoff et al 1994) and X-ray tomography (Imhoff et al 1996). The drawbacks of these techniques are rather expensive test facilities and generally poor spatial and temporal resolution, (Chang and Watson 1999;Gladden et al 2006).…”

Section: Introductionmentioning

confidence: 99%

Measurements of Transitional and Turbulent Flow in a Randomly Packed Bed of Spheres with Particle Image Velocimetry

et al. 2016

View full text Add to dashboard Cite

Particle image velocimetry (PIV) has been used to investigate transitional and turbulent flow in a randomly packed bed of mono-sized transparent spheres at particle Reynolds number, 20 < Re p < 3220. The refractive index of the liquid is matched with the spheres to provide optical access to the flow within the bed without distortions. Integrated pressure drop data yield that Darcy law is valid at Re p ≈ 80. The PIV measurements show that the velocity fluctuations increase and that the time-averaged velocity distribution start to change at lower Re p . The probability for relatively low and high velocities decreases with Re p and recirculation zones that appear in inertia dominated flows are suppressed by the turbulent flow at higher Re p . Hence there is a maximum of recirculation at about Re p ≈ 400. Finally, statistical analysis of the spatial distribution of time-averaged velocities shows that the velocity distribution is clearly and weakly self-similar with respect to Re p for turbulent and laminar flow, respectively.

show abstract

“…Typically, bulk mass transfer coefficients (i.e., intrinsic mass transfer coefficient x NAPLwater interfacial area) were determined by measuring effluent solute concentrations from columns containing residual NAPL. These experiments demonstrated that the dissolution rate is a function of NAPL saturation (defined as the ratio of NAPL volume to pore volume), grain size and uniformity, flow rate, and wettability [Imhoff et al, 1994;Geller and Hunt, 1993 [1997] determined values for the intrinsic mass transfer coefficient in a two-dimensional (2-D) glass bead micromodel by measuring the volume change of NAPL blobs and rings as they dissolved. They observed that the intrinsic mass transfer coefficient increased by a factor of 3 when the flow rate increased by 2 orders of magnitude, although there was considerable variability for a fixed flow rate.…”

Section: Introductionmentioning

confidence: 99%

Pore‐scale modeling of dissolution from variably distributed nonaqueous phase liquid blobs

Knutson¹,

Werth²,

Valocchi³

2001

Water Resources Research

View full text Add to dashboard Cite

Abstract. Contamination of groundwater by nonaqueous phase liquids (NAPLs) is widely recognized as a serious environmental problem. Predicting the dissolution, fate, and transport of these organic chemicals in the subsurface is challenging because geological heterogeneity exists at numerous scales. To better understand heterogeneity at the pore scale, we use the lattice Boltzmann (LB) method to simulate water flow and solute transport from distributed NAPL blobs in a two-dimensional porous media. The LB method approximates the momentum and mass transport equations at the pore scale, easily incorporating complex boundary conditions of the porous media. The effects of NAPL blob configuration and Peclet number (Pe) on steady state mass transfer are studied at 7% and 15% NAPL saturation. We find that the solute flux out of the simulated system decreases substantially as the transverse length over which NAPL blobs are distributed decreases; for example, the solute flux is reduced by a factor of 2 by confining the NAPL blobs to only half of the transverse length. Values of Sherwood numbers determined from our simulations are slightly less than values determined from previously published mass transfer correlations. Our results indicate that pore-scale NAPL configuration significantly affects mass transfer and that correlations should be modified to account for it. We find that the dimensionless mass transfer coefficient increases with Pe for the values used in our simulations, where the rate of increase decreases with increasing Pe. We observe that much of the variability in computed mass transfer coefficients is accounted for by differences in the NAPL-water interfacial area at high Pe. However, at lower Pe, variability remains due to NAPL configuration.

show abstract

An experimental study of complete dissolution of a nonaqueous phase liquid in saturated porous media

Cited by 325 publications

References 18 publications

Mass-removal and mass-flux-reduction behavior for idealized source zones with hydraulically poorly-accessible immiscible liquid

Mass-removal and mass-flux-reduction behavior for idealized source zones with hydraulically poorly-accessible immiscible liquid

Measurements of Transitional and Turbulent Flow in a Randomly Packed Bed of Spheres with Particle Image Velocimetry

Pore‐scale modeling of dissolution from variably distributed nonaqueous phase liquid blobs

Contact Info

Product

Resources

About