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HYSTERETIC MODELING ON THE CONVECTIVE TRANSPORT OF ORGANIC SOLVENT IN AN UNSATURATED SOIL ZONE
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  • Journal title : Environmental Engineering Research
  • Volume 11, Issue 5,  2006, pp.241-249
  • Publisher : Korean Society of Environmental Engineering
  • DOI : 10.4491/eer.2006.11.5.241
 Title & Authors
HYSTERETIC MODELING ON THE CONVECTIVE TRANSPORT OF ORGANIC SOLVENT IN AN UNSATURATED SOIL ZONE
Lee, Kun-Sang;
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 Abstract
A mathematical model is described for the prediction of convective upward transport of an organic solvent driven by evaporation at the surface, which is known as the major transport mechanism in the in-situ photolysis of a soil contaminated with 2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD). A finite-element model was proposed to incorporate the effects of multiphase flow on the distribution of each fluid, gravity as a driving force, and the use of hysteretic models for more accurate description of k-S-p relations. Extensive numerical calculations were performed to study fluid flow through three types of soils under different water table conditions. Predictions of relative permeability-saturation-pressure (k-S-p) relations and fluids distribution for an illustrative soil indicate that hysteresis effects may be quite substantial. This result emphasizes the need to use hysteretic models in performing flow simulations including reversals of flow paths. Results of additional calculations accounting for hysteresis on the one-dimensional unsaturated soil columns show that gravity affects significantly on the flow of each fluid during gravity drainage, solvent injection, and evaporation, especially for highly permeable soils. The rate and duration of solvent injection also have a profound influence on the fluid saturation profile and the amount of evaporated solvent. Key factors influencing water drainage and solvent evaporation in soils also include hydraulic conductivity and water table configuration.
 Keywords
2,3,7,8-tetrachlorodibenzo-p-dioxin(TCDD);Multiphase flow;Hysteresis;Mathematical model;
 Language
English
 Cited by
 References
1.
LaGrega, M. D., Buckingham, P. L., and Evans, J. C., Hazardous Waste Management, 2nd Ed., McGraw-Hill, Boston (2001)

2.
Dougherty, E. J., McPeters A. L., Overcast M. R., and Carbonell R. G., 'Theoretical analysis of a method forin situ decontamination of soil Containing 2,3,7,8-tetrachlorodibenzo-p-dioxin,' Environ. Sci. Tech., 27, 505-515 (1993) crossref(new window)

3.
Lee, S.-D. and Chung, I.-H., 'Study on evaporation from the soil affected by the particle size and soil water content,' J. Kor. Soc. of Env. Eng., 19(1), 1-8 (1997)

4.
Lee, S.-D., Park, S.-C., and Lee, K.-I., 'A study on the latent heat exchange model between soil and atmosphere,' J. Kor. Soc. of Env. Eng., 20(11), 1511-1522 (1998)

5.
Lee, K. S., 'Finite-element simulation on the water migration through a nonuniform unsaturated zone,' Computer Methods and Advances in Geomechanics, Desai et al. (eds), 837-842 (2001)

6.
Lee, K. S., 'Finite-element modeling on the convective transport of an organic solvent through nonuniform soils during in-situ photolysis process,' Environ. Eng. Res., 8(3), 122-129 (2003) crossref(new window)

7.
Yang, M. and Yanful, E. K., 'Water balance during evaporation and drainage in cover soils under different water table conditions,' Adv. in Water Resourses, 24, 505-521 (2002)

8.
van Genutchen, M. Th., 'A closed-form equation for predicting the hydraulic conductivity of unsaturated soils,' Soil Sci. Soc. Am. J., pp. 892-898 (1980)

9.
Helmig, R., Multiphase Flow and Transport Processes in the Subsurface, Springer, Berlin, Germany, 47-82 (1997)

10.
Mualem, Y., 'A new model for predicting the hydraulic conductivity of unsaturated porous media', Water Resources Res., 12(3), 513-522 (1976) crossref(new window)

11.
Vogel, T., van Genuchten M. Th., and Cislerova, M., 'Effect of the shape of the soil hydraulic functions near saturation on variably-saturated predictions,' Adv. in Water Resourses, 24, 133-144 (2001)

12.
Lee, K.S., 'Effects of hysteresis in hydraulic properties on the water flow through an unsaturated zone,' J. Kor. Soc. of Geosys. Eng., 41(3), 187-193 (2004)

13.
Lide, D. R., CRC Handbook of Chemistry and Physics, 83rd Edition, CRC Press, Boca Raton (2002)

14.
Carsel, R. F. and Parrish, R. S., 'Developing joint probability distributions of soil water retention characteristics,' Water Resources Res., 24(5), 755-769 (1988) crossref(new window)