Modification of chemical and physical factors in steamflood to increase heavy oil recovery. Annual report, October 1, 1994--September 30, 1995

摘要

The objectives of this contract is to carry our fundamental research in heavy oil recovery in: displacement and flow properties of fluids involving phase change (condensation-evaporation) in porous media; flow properties of mobility control fluids (such as foam); and the effect of reservoir heterogeneity on oil recovery. This report covers the work performed in these three areas in the past year. In the area of vapor-liquid flow, we present a theoretical and numerical study of steam injection in a pore network. We characterize the displacement in terms of an effective mobility ratio and heat transfer parameters. In another study, we discuss the problem of steam injection in fractured systems using visualization with micromodels. The interplay of drainage, imbibition and bubble growth is visualized. Conclusions are reached regarding the potential for steamflooding fractured systems. A third study focuses on the development of a pore-network model for foam formation and propagation in porous media. This model, for the first time, accounts for the fundamental mechanisms of foam propagation at the microscale and leads to the determination of various parameters that are currently treated empirically.