Mass transfer from non-aqueous phase liquids to the aqueous phase in groundwater systems

As immiscible organic contaminants migrate through the subsurface environment, a significant portion of non-aqueous phase liquids (NAPL's) is trapped by capillary forces and remains in the subsurface as immobile blobs or ganglia. Residual saturations of NAPL on the order of 5-30 percent have been observed in saturated subsurface systems. The NAPL can partition into the aqueous phase and serve as a long-term source of groundwater contamination. NAPL-aqueous mass transfer rates impact the distribution and the rate of movement of the contaminant within the subsurface. The mass transfer coefficient is a function of many variables including aqueous phase velocity and NAPL-aqueous interfacial area. A one-dimensional column apparatus and experimental procedure was developed to study the nature of mass transfer between the aqueous phase (water), and a non-aqueous phase liquid (NAPL) in porous media. The NAPLs used in the experiments were composed of soluble and insoluble (inert) compounds. These experiments were designed to investigate the aqueous mass transfer of benzene, toluene, ethylbenzene, and xylene from and inert compound (soltrol or hexadecane). The results of this research indicate that the rate of NAPL-aqueous interphase mass transfer increases as a function of increasing aqueous phase velocity and percent NAPL saturation. Miller's equation was used to compare the model performance. Comparison of the experimental K values obtained by the literature was performed. The results indicated a satisfactory model performance.

Name thesis:degree_name

Master of Science

Level thesis:degree_level

masters

Discipline thesis:degree_discipline

Environmental Planning

Department dc:contributor.department

Environmental Engineering

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

1992

Author dc:creator

• Jayaraman, Krithika M.

Chair dc:contributor.committeechair

• Parker, Jack C.

Committee members dc:contributor.committeemember

• Dietrich, Andrea M.
• Gallagher, Daniel L.

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en

Dc Identifier Other

etd-01122010-020214

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/40620