Abstract
Thermal recovery is the most utilized enhanced oil recovery method. The modeling of thermal recovery processes not only requires relative permeability functions, but also information about the effects of temperature on these functions. There are significant challenges encountered when estimating relative permeability from laboratory data, such as accuracy of measurements and generalizing assumptions in the interpretation techniques. A novel method is used here to estimate relative permeability and capillary pressure from in-situ aqueous phase saturation profiles obtained utilizing computerized tomography (CT) scanning during imbibition experiments. Relative permeability and capillary pressure functions are interpreted simultaneously including nonequilibrium effects. Moreover, the use of B-spline coefficients allows the estimation of arbitrary shaped functions. Results obtained show a shift toward increased water-wettability with increasing temperature for diatomite reservoir core. The measured changes in relative permeability are linked to the effect of temperature on surface forces and ultimately to rock-fluid interactions.
