Comparison Of Three Methods Of Relative Permeability Measurement

Relative permeability curve shapes of granular carbonate cores from a Middle East reservoir were comparable regardless of the conditions and methods of measurement. However, variations among the tests in flow rate, viscosity ratio, and pore volumes of water injected did affect residual oil saturation. Thus, this research confirms the importance of reservoir condition relative permeability measurements because of the significant impact of test conditions on residual oil saturation. The three types of measurements were ambient condition unsteady-state, ambient condition steady-state, and reservoir condition unsteady-state. This study provided a unique opportunity to compare relative permeabilities from these different methods on the same core. All data were from first cycle waterfloods on restored-state core. The rock/fluid interaction was oil-wetting in character. Although the residual oil saturation varied, the shapes of the relative permeability curves from the three methods were similar. In addition, a new equation was developed for normalizing relative permeability curves, which accounts for the different residual oil saturations of the various samples.