Article: Cyclic injection of CO2 into a saline aquifer with extended interface Journal: International Journal of Global Environmental Issues (IJGENVI) 2017 Vol.16 No.4 pp.231 - 253 Abstract: Cyclic CO2 injection is considered to be an effective method to maximise CO2 dissolution in hydrocarbon reservoirs (Reznik et al., 1984; Monger et al., 1991) and saline aquifers (Zhang and Agarwal, 2012; Dusseault et al., 2012). Gravity override and evolution of a transition zone have large effects on the development of a saturation transition zone between the pure host fluid and the injected gas. In this paper, equivalent relative permeability functions are derived to address the effect of gravity override, allowing reduction of the problem dimension from 2D to 1D. An analytical solution for saturation distribution in a cyclic drainage-imbibition process is obtained. To incorporate the solubility of CO2 in the aqueous phase, a one-way coupled approximation is used and a numerical solution is proposed for derivation of compositional distribution of the chemical species. Information about saturation distribution from the analytical solution provides saturation distribution over time and distance, and this is substituted in the concentration distribution equation. In contrast to previously well-studied analytical solutions (e.g., Orr, 2007), this hybrid scheme includes the effect of kinetic mass transfer and dispersion, and provides a reasonable approximation for saturation-concentration distribution during injection. Inderscience Publishers - linking academia, business and industry through research

Title: Cyclic injection of CO₂ into a saline aquifer with extended interface

Authors: Farshad A. Malekzadeh; Yuri Leonenko; Maurice Dusseault

Addresses: Computer Modelling Group, Calgary, Alberta, Canada ' Department of Earth Sciences, University of Waterloo, Waterloo, Ontario, Canada ' Department of Earth Sciences, University of Waterloo, Waterloo, Ontario, Canada

Abstract: Cyclic CO₂ injection is considered to be an effective method to maximise CO₂ dissolution in hydrocarbon reservoirs (Reznik et al., 1984; Monger et al., 1991) and saline aquifers (Zhang and Agarwal, 2012; Dusseault et al., 2012). Gravity override and evolution of a transition zone have large effects on the development of a saturation transition zone between the pure host fluid and the injected gas. In this paper, equivalent relative permeability functions are derived to address the effect of gravity override, allowing reduction of the problem dimension from 2D to 1D. An analytical solution for saturation distribution in a cyclic drainage-imbibition process is obtained. To incorporate the solubility of CO₂ in the aqueous phase, a one-way coupled approximation is used and a numerical solution is proposed for derivation of compositional distribution of the chemical species. Information about saturation distribution from the analytical solution provides saturation distribution over time and distance, and this is substituted in the concentration distribution equation. In contrast to previously well-studied analytical solutions (e.g., Orr, 2007), this hybrid scheme includes the effect of kinetic mass transfer and dispersion, and provides a reasonable approximation for saturation-concentration distribution during injection.

Keywords: CO₂ sequestrations; cyclic injection; analytical solution; hyperbolic equation; dissolution trapping.

DOI: 10.1504/IJGENVI.2017.086714

International Journal of Global Environmental Issues, 2017 Vol.16 No.4, pp.231 - 253

Accepted: 04 Apr 2017
Published online: 21 Sep 2017 *

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Title: Cyclic injection of CO2 into a saline aquifer with extended interface

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Title: Cyclic injection of CO₂ into a saline aquifer with extended interface