The Calculation of Oil-water Relative Permeability From Capillary Pressure Data in an Oil-wet Porous Media: Case Study in a Dolomite Reservoir

Abstract

Estimating relative permeability curves from capillary pressure data is a well-known technique and the reliability of these techniques for approximation of liquid-gas relative permeability curves had thoroughly investigated. However, there is not enough information to conclude which method is the standard one for calculating oil-water relative permeability curves. The authors utilized various capillary pressure techniques such as the Corey, Brooks-Corey, Li-Purcell, and Li-Burdine methods to calculate oil-water relative permeabilities using the measured oil-water capillary pressure data in drainage process in an oil-wet Dolomite reservoir. Despite wide popularity of Purcell and Burdine methods for calculating relative permeability, the authors used new Li-Purcell and Li-Burdine methods. The calculated results were compared to the experimental data of oil-water relative permeabilities measured in a Dolomite reservoir. The Corey and Brooks-Corey models show an acceptable and nearly exact match with the measured oil relative permeability values. However, the Li-Purcell and Li-Burdine models underestimate the values for wetting phase in most cases. It is also worth mentioning that, except Li-Purcell method, the results of all other methods for calculating nonwetting phase relative permeability are almost the same and they are in good agreement with the measured data. Results of this work reveal that calculation of oil-water relative permeability using the capillary pressure data is also a reliable technique in oil-wet systems.