Download or read book Influence of Wettability on Dense Nonaqueous Phase Liquid DNAPL Constitutive Relationships in Saturated Porous Media written by Denis Michael O'Carroll and published by . This book was released on 2004 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multiple Experimental Realizations of Dense Nonaqueous Phase Liquid Spreading in Water saturated Heterogeneous Porous Media written by Ronald Compos and published by . This book was released on 1998 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2004 with total page 882 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Migration and Entrapment of DNAPLs in Heterogeneous Systems written by and published by . This book was released on 2001 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previously funded EMSP research efforts have been directed towards the quantification of dense nonaqueous phase liquid (DNAPL) migration and entrapment behavior in physically and chemically heterogeneous systems. This important research has demonstrated that chemical heterogeneities can have a significant influence on DNAPL fate and persistence. Previous work, however, has been limited to pure DNAPLs and well defined aqueous and solid surface chemistries. Subsurface chemical heterogeneities at many DOE sites are generally more complex as a result of the disposal of mixtures of wastes into heterogeneous subsurface environments. The research planned in this project seeks to build upon our previous research experience and expertise to explore the influence of waste and porous media composition on DNAPL migration and entrapment in the saturated zone. DNAPL mixtures and soils typical of those found across the DOE complex will be used in these studies. Many of the experimental procedures and protocols to be employed are based upon those developed under previous EMSP funding. This past work also provides the conceptual framework for characterizing and interpreting experimental results, mathematical model development, and inverse modeling protocols. Specific objectives of this research are identified below: (1) Relate measured interfacial properties for representative wastes and soils to parameters such as mineralogy, organic carbon content, pH, ionic strength, and DNAPL acid and base numbers. (2) Assess predictive procedures to estimate interfacial properties for DOE wastes and soils. (3) Deduce mechanisms of interfacial property alteration. (4) Quantify the influence of waste and porous medium composition on hydraulic properties and residual saturation. (5) Develop and assess constitutive hydraulic property and residual saturation models. (6) Explore the migration and entrapment behavior of model DNAPL wastes in spatially and temporally heterogeneous systems. (7) Develop and validate a multiphase flow model to simulate the migration and entrapment of model DNAPL wastes in heterogeneous systems. (8) Investigate the upscaling of findings from batch and soil column experiments to larger systems.
Download or read book Influence of Wettability on Constitutive Relations and Its Role in Upscaling written by and published by . This book was released on 1998 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: The lattice Boltzmann (LB) method is applied to simulating multifluid flow in porous media at sub-pore resolution to determine constitutive behaviors. The authors address the importance of the LB technique for identifying process based constitutive relationships, and demonstrate its application through analysis of the influence of wettability on interfacial areas and constitutive relationships. Porous media surface wettability is varied from uniformly strongly wetted by the resident fluid through strongly wetted by the displacing fluid. Spatially variable wettability is also demonstrated. Primary imbibition and drainage displacements are run, and interfacial areas (IFA) as a function of time are determined and compared. Results indicate that wettability is an important factor in displacement behavior and resulting interfacial area. Primary imbibition in a strongly wet material under capillary dominated flows produces film flow, resulting in high IFAs that decrease with increasing saturation and viscous forces. Primary drainage produces initially high IFA that decreases slightly with increasing saturation or pressure drop. Surfaces with spatially variable wetting can have a strong influence on resulting fluid distributions and fluid flow.
Download or read book Wettability Effects on Flow Through Porous Media written by Sandeep Dhawan and published by . This book was released on 1994 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Subsurface Compositional Simulation Incorporating Solute chemistry Dependent Interfacial Properties written by Thomas John Phelan and published by . This book was released on 2004 with total page 610 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Resolving the Impact of Biological Processes on DNAPL Transport in Unsaturated Porous Media Through Nuclear Magnetic Resonance Relaxation Time Measurements written by Gill G. Geesey and published by . This book was released on 2004 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: This research leads to a better understanding of how physical and biological properties of porous media influence water and dense non-aqueous phase liquid (DNAPL) distribution under saturated and unsaturated conditions. This project exploits the capability of low-field nuclear magnetic resonance (NMR) proton relaxation decay-rate measurements for determining environmental properties affecting DNAPL solvent flow in the subsurface, including determining if DNAPL exist in water-wet or solvent-wet environments, the pore-size distribution of the soils containing DNAPLs, and the impact of biological processes on their transport mechanisms in porous media. Knowledge of the in-situ flow properties and pore distributions of organic contaminants are critical to understanding where and when these fluids will enter subsurface aquifers.
Download or read book Migration and Entrapment of DNAPLs in Heterogeneous Systems written by Linda M. Abriola and published by . This book was released on 2003 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Previously funded EMSP research efforts were directed towards the quantification of dense non-aqueous phase liquid (DNAPL) migration and entrapment behavior in physically and chemically heterogeneous systems. This research demonstrated that chemical heterogeneities can have a significant influence on DNAPL fate and persistence. Previous work, however, was limited to examination of the behavior of pure DNAPLs in systems with simple and well-defined aqueous and solid surface chemistry. The subsurface chemical environments at many DOE sites, however, are generally more complex than these idealized systems, due to the release of complex mixtures of wastes and more complex physical and chemical heterogeneity. The research undertaken in this project seeks to build upon our previous research experience and expertise to explore the influence of waste and porous media composition on DNAPL migration and entrapment in the saturated zone. DNAPL mixtures and soils typical of those found across the DOE complex will be used in these studies. Many of the experimental procedures and protocols are based upon those developed under previous EMSP funding. This past work also provides the conceptual framework for characterizing and interpreting experimental results, mathematical model development, and inverse modeling protocols. Specific objectives of this research include: (1) Relate measured interfacial properties for representative wastes and soils to parameters such as mineralogy, organic carbon content, pH, ionic strength, and DNAPL acid and base numbers. (2) Assess predictive procedures to estimate interfacial properties for DOE wastes and soils. (3) Deduce mechanisms of interfacial property alteration. (4) Quantify the influence of waste and porous medium composition on hydraulic properties and residual saturation. (5) Develop and assess constitutive hydraulic property and residual saturation models. (6) Explore the migration and entrapment behavior of model DNAPL wastes in spatially an d temporally heterogeneous systems. (7) Development and validation a multiphase flow model to simulate the migration and entrapment of model DNAPL wastes in heterogeneous systems. (8) Investigate the up-scaling of findings from batch and soil column experiments to larger systems.
Download or read book Delivery and Mixing in the Subsurface written by Peter K. Kitanidis and published by Springer Science & Business Media. This book was released on 2012-04-23 with total page 351 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume is meant to provide the practitioner with information on the natural mixing processes occurring in aquifers as well as to describe basic strategies that can be implemented to enhance mixing in particular cases. For example, when it comes to mixing miscible liquids, one can speed up mixing in the formation by manipulating the flow such as through the use of recirculation wells. Furthermore, much of the mixing can be achieved partially within recirculation wells themselves, where contaminated water is admixed with additives, volatile products may be removed through a vapor mass exchanger, etc. Thus, adding mixing wells can significantly increase the performance of the delivery and mixing system and speed up the process of remediation.
Download or read book The Migration and Entrapment of DNAPLs in Physically and Chemically Heterogeneous Porous Media Final Report 09 written by and published by . This book was released on 2000 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hazardous dense nonaqueous phase liquids (DNAPLs), such as chlorinated solvents, are slightly water soluble and pose a serious threat to soil and groundwater supplies in many portions of the United States. The migration and entrapment of DNAPLs in the subsurface environment is typically believed to be controlled by physical heterogeneities; i.e, layers and lenses of contrasting soil texture. The rationale for this assumption is that capillarity, as determined by the soil texture, is the dominant transport mechanism. Capillarity also depends on interfacial tension and medium wettability. Interfacial tension and medium wettability may be spatially and temporally dependent due to variations in aqueous phase chemistry, contaminant aging, and/or variations in mineralogy and organic matter distributions. Such chemical heterogeneities have largely been ignored to date, even though they are known to have dramatic effects on the hydraulic property relations. Numerical multiphase flow and transport models typically assume that solids are water-wet and that interfacial tension is constant. The primary objective of this research is to investigate the influence of coupled physical and chemical heterogeneities on the migration and entrapment of DNAPLs. This objective will be accomplished through a combination of laboratory and numerical experiments. Laboratory experiments will be conducted to examine: (i) aqueous phase chemistry effects on medium wettability and interfacial tension; and (ii) relative permeability-saturation-capillary pressure relations for chemically heterogeneous systems. An important objective of this research is to modify a two-dimensional multiphase flow and transport model to account for chemically and physically heterogeneous systems. This numerical simulator will be used in conjunction with independently measured parameters to simulate two-dimensional DNAPL infiltration experiments. Comparisons of simulated and laboratory data will provide a means to experimentally validate this model. The validated numerical simulator will subsequently be employed to investigate various innovative remediation schemes such as the use of surfactants and in situ wettability alteration. The accomplishment of the research herein will: (i) lead to a better understanding of the way aqueous phase chemistry changes medium wettability; (ii) validate and/or lead to the development of methods to predict and model wettability on hydraulic property relations; (iii) lead to the development of a multiphase flow simulator that accounts for fractional wettability and concentration dependent interfacial properties; (iv) lead to an improved knowledge of the effects of pore-scale variability on scale-up issues in multiphase systems; (v) provide an understanding of the interaction of chemical and physical heterogeneity on DNAPL flow and entrapment; (vi) provide two-dimensional laboratory data sets to validate multiphase flow models for physically and chemically heterogeneous systems; and (vii) facilitate the development and implementation of innovative remediation strategies.
Download or read book Dissolution of Non aqueous Phase Liquid Pools in Saturated Porous Media written by Michael P. Whelan and published by . This book was released on 1992 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Treating Dense Nonaqueous phase Liquids DNAPLs written by Godage B. Wickramanayake and published by . This book was released on 2000 with total page 272 pages. Available in PDF, EPUB and Kindle. Book excerpt: - DNAPL Site Characterization- DNAPL Modeling- DNAPL Remediation Technologies- DNAPLs in Fractured Media- Surfactant/Cosolvent Flushing.
Download or read book Mean and Variance of DNAPL Ringer Development in a Saturated Randomly Heterogeneous Porous Medium written by and published by . This book was released on 2001 with total page 1 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chlorinated organic solvents such as TCE and PCE are among the most ubiquitous and problematic groundwater contaminants at many sites. They usually enter the subsurface in the form of organic liquids which exhibit low miscibility with water and thus form a separate dense non-aqueous phase liquid (DNAPL). Here we analyze the movement of DNAPL in a three-dimensional randomly heterogeneous porous medium saturated with water. We consider the fluid interface between DNAPL and water to form a sharp boundary at which the capillary pressure head, assumed equal to the entry pressure head of DNAPL, is prescribed either deterministically or randomly. We treat log hydraulic conductivity as a statistically homogeneous random field with given mean, variance and covariance, This allows us to cast the corresponding boundary-value problem in the form of an integro-differential equation, in which the parameters and domain of integration are random. Expanding this equation in a Taylor series about the mean position of the front, and averaging in probability space, yields leading-order ensemble I moment equations for the mean and variance of front evolution with time. Previously we solved these moment equations analytically in one-dimension with gravity, to first order in the variance of log conductivity, and compared our solution with the results of Monte Carlo sjmulations. Here we solve the same moment equations numerically in two-spatial dimensions without gravity.
Download or read book Viscous Effects in Pore Scale Modeling of Immiscible Fluid Flow Through Porous Media written by and published by . This book was released on 1999 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sites contaminated with dense nonaqueous phase liquids (DNAPLs) such as chlorinated solvents are, typically, exceptionally difficult to characterize because the unstable nature of the front results in complex distributions that are erratic, highly fingered and sensitive to small-scale heterogeneities. However, DNAPL source zone characterization is important for risk assessments, feasibility studies and identification of appropriate remediation technologies at DNAPL-contaminated sites. The extent and configuration of the source zone is also important input to multiphase mass transfer models. Pore scale models capture the essential physics of the multiphase migration process without the need to solve the large systems of equations inherent in continuum modeling. This research project developed a modified diffusion limited aggregation model that can be used to predict source zone geometry when viscous effects are important. A unique relationship between the model input parameter, the sticking probability and the essential properties governing the DNAPL-water front displacement was developed. The model was compared with both homogeneous and heterogeneous laboratory experiments. Model and laboratory results were found to compare well.
Download or read book The Behaviour of Dense Non aqueous Phase Liquid Contaminants in Heterogeneous Porous Media written by Bernard Helmut Kueper and published by . This book was released on 1989 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Investigation of Fingering of Dense Nonaqueous Phase Liquids in Saturated Porous Media written by Rudolf Josef Held and published by . This book was released on 1993 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
