Journal of Soil and Groundwater Environment (한국지하수토양환경학회지:지하수토양환경)

Korean Society of Soil and Groundwater Environment (한국지하수토양환경학회)
권호 표지
DOI QR코드

DOI QR Code

Decrease in the Thickness of Capillary Fringe Induced by Surface Active Chemicals in the Groundwater

계면활성물질의 지하수적용에 의한 모관수대 두께의 감소

  • Kim, Heonki (Dept. of Environmental Sciences and Biotechnology, Hallym University, Institute of Energy and Environment, Hallym University) ;
  • Shin, Seungyup (Dept. of Environmental Sciences and Biotechnology, Hallym University, Institute of Energy and Environment, Hallym University) ;
  • Yang, Haewon (Dept. of Environmental Sciences and Biotechnology, Hallym University, Institute of Energy and Environment, Hallym University)
  • 김헌기 (한림대학교 환경생명공학과, 한림대학교 에너지.환경 연구소) ;
  • 신승엽 (한림대학교 환경생명공학과, 한림대학교 에너지.환경 연구소) ;
  • 양해원 (한림대학교 환경생명공학과, 한림대학교 에너지.환경 연구소)
  • Received : 2012.10.09
  • Accepted : 2012.11.28
  • Published : 2012.12.31
Download PDF
⟨ Previous Next ⟩

Abstract

Capillary fringe divides the groundwater and the vadose zone controlling the diffusive mass transfer of contaminants and gases. The thickness of capillary fringe is of great importance for the rate of contaminant mass transfer across the capillary fringe. Application of surface active chemicals including surfactants and alcohol-based products into the subsurface environment changes the surface tension of the aqueous phase, which in turn, affects the thickness of the capillary fringe. In this study, a bench-scale model was used to assess the quantitative relationship between the surface tension and the thickness of the capillary fringe. An anionic surfactant (Sodium dodecylbenzene sulfonate, SDBS) and an aqueous solution of ethanol were used to control the surface tension of the groundwater. It was found that the thickness of the capillary fringe is directly proportional to the surface tension. The air entry pressures measured by the Tempe Pressure Cell at different surface tensions using SDBS (200 mg/L) and ethanol (20%, v/v) solutions were in good agreement with the thicknesses of the capillary fringe measured by the model. A simple method to correct the conventional Brooks-Corey model for estimating the air entry pressure was also presented.

Keywords

References

  1. Affek, H.P., Ronen, D., and Yakir, D., 1998, Production of $CO_{2}$ in the capillary fringe of a deep phreatic aquifer, Water Resour. Res., 34, 989-996. https://doi.org/10.1029/98WR00095
  2. Baehr, A.L., 1987, Selective transport of hydrocarbons in the unsaturated zone due to aqeuous and vapor-phase partitioning, Water Resour. Res., 23, 1926-1938. https://doi.org/10.1029/WR023i010p01926
  3. Bear, J. and Cheng, A.H.-D., 2010, Modeling Groundwater Flow and Contaminant Transport, 23rd Volume, Springer, New York.
  4. Brooks, M.C., Annable, M.D., Suresh, P.S.C., Hatfield, K., Jawitz, J.W., Wise, W.R., Wood, A.L., and Enfield, C.G., 2004, Controlled release, blind test of DNAPL remediation by ethanol flushing, J. Contam. Hydrol., 69, 281-287. https://doi.org/10.1016/S0169-7722(03)00158-X
  5. Brooks, R.H. and Corey, A.T., 1966, Properties of porous media affecting fluid flow, J. Irrig. and Drainage Div., Proc. ASCE, 92, 61-88.
  6. Corey, A.T., 1994, Mechanics of Immiscible Fluids in Porous Media, Water Resources Publications, Highlands Ranch, Colorado, p. 104.
  7. Freitas, J.F. and Barker, J.F., 2011, Oxygenated gasoline release in the unsaturated zone-Part 1: Source zone behavior, J. Contam. Hydrol., 126, 153-166. https://doi.org/10.1016/j.jconhyd.2011.07.003
  8. Henry, E.J. and Smith, J.E., 2002, The effect of surface-active solutes on water flow and contaminant transport in variably saturated porous media with capillary fringe effect, J. Contam. Hydrol., 56, 247-270. https://doi.org/10.1016/S0169-7722(01)00206-6
  9. Kim, H., Choi, K, -M., Moon, J. -W., and Annable, M.D., 2006. Changes in air saturation and air-water interfacial area during surfactant-enhanced air sparging in saturated sand, J. Contam. Hydrol., 88, 23-35. https://doi.org/10.1016/j.jconhyd.2006.05.009
  10. Klenk, I.D. and Grathwohl, P., 2002, Transvers vertical dispersion in groundwater and the capillary fringe, J. Contam. Hydrol., 58, 111-128. https://doi.org/10.1016/S0169-7722(02)00011-6
  11. Maier, U., Rugner, H., and Grathwohl, P., 2007, Gradients controlling natural attenuation of ammonia, Applied Geochemistry, 22, 2606-2617. https://doi.org/10.1016/j.apgeochem.2007.06.009
  12. McCarty, K.A. and Johnson, R.L., 1993, Transport of volatile organic compounds across the capillary fringe, Water Resour. Res., 29, 1675-1683. https://doi.org/10.1029/93WR00098
  13. Ronen, D., Scher, H., and Blunt, M., 1997, On the structure and flow processes in the capillary fringe of phreatic aquifer, Tranport in Porous Media, 28, 159-180. https://doi.org/10.1023/A:1006583410617
  14. van Genuchten, M. Th., 1980, A Closed-form equation for predicting the hydraulic conuductivity of unsaturated soils, Soil Sci. Soc. Am. J., 44, 892-898. https://doi.org/10.2136/sssaj1980.03615995004400050002x
  15. Zhong, L., Mayer, A.S., and Pope, G.A., 2003, The effects of surfactant formulatioin on nonequilibrium NAPL solubilization, J. Contam. Hydrol., 60, 55-75. https://doi.org/10.1016/S0169-7722(02)00063-3