Electrokinetic Remediation Modeling Incorporating Geochemical Effects
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 134, Issue 1
Abstract
Electrokinetic remediation technology is one of the developing technologies that offers great promise for the cleanup of soils contaminated with heavy metals. However, the performance of an electrokinetic remediation system depends on the interaction of a complex set of interrelated system variables and parameters. Many of these interactions were addressed in this study by incorporating geochemical reactions into electrokinetic remediation modeling. A one-dimensional transport model was developed to predict the transport and speciation of heavy metals (chromium, nickel, and cadmium) in soil during electrokinetic remediation as a function of time and space. The model incorporates: (1) pH-dependent adsorption of contaminants to the soil surface; (2) sensitivity of soil surface potential and electroosmotic flow to the pore water properties; and (3) synergistic effects of multiple chemical species on electrokinetic remediation. The model considers that: (1) Electrical potential in the soil is constant with time; (2) surface complexation reactions are applicable in the highly concentrated clay suspensions; (3) the effect of temperature is negligible; and (4) dissolution of soil constituents is negligible. The predicted pH profiles, electroosmotic flow, and transport of chromium, nickel, and cadmium in kaolin soil during electrokinetic remediation were found to reasonably agree with the bench-scale electrokinetic experimental results. The predicted contaminant speciation and distribution (aqueous, adsorbed, and precipitated) allow for an understanding of the transport processes and chemical reactions that control electrokinetic remediation.
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References
Acar, Y. B., and Alshawabkeh, A. N. (1993). “Principles of electrokinetic remediation.” Environ. Sci. Technol., 27(13), 2638–2647.
Acar, Y. B., Hamed, J. T., Alshawabkeh, A. N., and Gale, R. J. (1994). “Removal of cadmium(II) from saturated kaolinite by the application of electric current.” Geotechnique, 44(3), 239–254.
Al-Hamdan, A. Z. (2002). “Speciation, distribution and mobility of heavy metals in soils during electrokinetic remediation.” Ph.D. thesis, Univ. of Illinois at Chicago, Chicago.
Al-Hamdan, A. Z., and Reddy, K. R. (2005). “Surface speciation modeling of heavy metals in kaolin: Implications for electrokinetic soil remediation processes.” Adsorption, 11(5–6), 525–542.
Allison, J. D., Brown, D. S., and Novo-Gradack, K. J. (1991). MINETQA2/PRODEFA2: A geochemical assessment model for environmental systems, user’s manual, U.S. Environmental Protection Agency, Athens, Ga., EPA/600/3–91/021.
Alshawabkeh, A. N. (1994). “Theoretical and experimental modeling of removing contaminants from soils by electric field.” Ph.D. thesis, Louisiana State Univ., Baton Rouge, La.
Alshawabkeh, A. N., and Acar, Y. B. (1992). “Removal of contaminants from soils by electrokinetics: A theoretical treatise.” J. Environ. Sci. Health, Part A: Toxic/Hazard. Subst. Environ. Eng., 27(7), 1835–1861.
Alshawabkeh, A. N., and Acar, Y. B. (1996). “Electrokinetic remediation. II: Theoretical model.” J. Geotech. Engrg., 122(3), 186–196.
Bruell, C. J., Segall, B. A., and Walsh, M. T. (1992). “Electroosmotic removal of gasoline hydrocarbons and TCE from clay.” J. Environ. Eng., 118(1), 68–83.
Carnahan, B., Luther, H. A., and Wilkes, J. O. (1969). Applied numerical methods, Wiley, New York.
Carroll-Webb, S. A., and Walther, J. V. (1988). “A surface complex reaction model for the pH-dependence of corundum and kaolinite dissolution rates.” Geochim. Cosmochim. Acta, 52(11), 2609–2623.
Choi, Y. S., and Lui, R. (1995). “A mathematical model for the electrokinetic remediation of contaminated soil.” J. Hazard. Mater., 44(1), 61–75.
Corapcioglu, M. Y. (1991). “Formulation of electroosmotic processes in soils.” Transp. Porous Media, 6(4), 435–444.
Elliott, H. A., Liberati, M. R., and Huang, C. P. (1986). “Competitive adsorption of heavy metals by soils.” J. Environ. Qual., 15(3), 214–219.
Eykholt, G. R. (1992). “Driving and complicating features of electrokinetic treatment of soils.” Ph.D. thesis, Univ. of Texas at Austin, Austin, Tex.
Eykholt, G. R., and Daniel, D. E. (1994). “Impact of system chemistry on electroosmosis in contaminated soil.” J. Geotech. Engrg., 120(5), 797–815.
Haran, B. S., Popov, B. N., Zheng, G., and White, R. E. (1997). “Mathematical modeling of hexavalent chromium decontamination from low surface charged soils.” J. Hazard. Mater., 55(1–3), 93–107.
Jacobs, R. A., Sengun, M. Z., Hicks, R. E., and Probstein, R. F. (1994). “Model and experiments on soil remediation by electric fields.” J. Environ. Sci. Health, Part A: Toxic/Hazard. Subst. Environ. Eng., 29(9), 1933–1955.
James, R. O., and Parks, G. A. (1982). “Characterization of aqueous colloids by their electric double-layer and intrinsic surface chemical properties.” Surf. Colloid Sci., 12, 119–216.
Jenne, E. A. (1998). Adsorption of metals by geomedia: Variables, mechanisms and model applications, Academic, New York.
Kim, G. (1998). “Two-dimensional numerical modeling of electrokinetic extraction of contaminants from fine-grained soils.” Ph.D. thesis, Texas A&M Univ., College Station, Tex.
Lide, D. R., ed. (1993). CRC handbook of chemistry and physics, 73rd Ed., CRC, Boca Raton, Fla.
Lindgren, E. R., Mattson, E. D., and Kozak, M. W. (1992). “Electrokinetic remediation of unsaturated soils.” Emerging Technologies in Hazardous Waste Management. IV: ACS Symposium Series, D. W. Tedder and F. G. Pohland, eds., American Chemical Society, Atlanta, 33–50.
Langmuir, D. (1997). Aqueous environmental geochemistry, Prentice- Hall, Englewood Cliffs, N.J.
Menon, R. M. (1996). “Numerical modeling and experimental studies on electrokinetic extraction.” Ph.D. thesis, Texas A&M Univ., College Station, Tex.
Mitchell, J. K. (1993). Fundamentals of soil behavior, Wiley, New York.
Pamukcu, S., Weeks, A., and Wittle, J. K. (2004). “Enhanced reduction of Cr(VI) by direct electric current in a contaminated clay.” Environ. Sci. Technol., 38(4), 1236–1241.
Probstein, R. F., and Hicks, R. E. (1993). “Removal of contaminants from soils by electric fields.” Science, 260(5107), 498–503.
Reddy, K. R., Chinthamreddy, S., and Al-Hamdan, A. Z. (2001). “Synergistic effects of multiple metal contaminants on electrokinetic remediation of soils.” Remediation, 11(3), 85–109.
Schecher, W. D., and McAvoy, W. D. (1994). : A chemicalequilibrium program for personal computer, user’s manual, version 3.0, Environmental Research Software, Hallowell, Me.
Schnoor, J. L. (1995). Environmental modeling: Fate and transport of pollutants in water, air and soil, Wiley, New York.
Shapiro, A. P., and Probstein, R. F. (1993). “Removal of contaminants from saturated clay by electroosmosis.” Environ. Sci. Technol., 27(2), 283–291.
Snoeyink, V. L., and Jenkins, D. (1980). Water chemistry, Wiley, New York.
Sposito, G. (1989). Chemistry of soils, Oxford University Press, New York.
Stumm, W., and Morgan, J. J. (1996). Aquatic chemistry, 3rd Ed., Wiley, New York.
Yeung, A. T., and Datta, S. (1995). “Fundamental formulation of electrokinetic extraction of lead.” Can. Geotech. J., 32(4), 569–583.
Yu, J. W., and Neretnieks, I. (1996). “Modeling of transport and reaction processes in a porous medium in an electric field.” Chem. Eng. Sci., 51(19), 4355–4368.
Zachara, J. M., Ainsworth, C. C., Schmidt, R. L., and Resch, C. L. (1988). “Influence of cosolvents on quinoline sorption by subsurface materials and clays.” J. Contam. Hydrol., 2(4), 343–364.
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© 2008 ASCE.
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Received: Sep 20, 2006
Accepted: May 15, 2007
Published online: Jan 1, 2008
Published in print: Jan 2008
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