Liberation of Solution Gas During Pressure Depletion of Virgin and Watered-Out Oil Reservoirs

Abstract

Summary Multipurpose experimental equipment was constructed to investigate the buildup of gas saturation during depressurization of virgin and watered-out oil reservoirs at representative conditions. The measured dependencies of critical gas saturations on gas/oil interfacial tension (IFT), amount of dissolved gas, pressure-decline rate, and structure of the porous medium are discussed. In addition, experimental results indicating significant reductions of waterflood residual oil saturation (ROS) owing to the presence of a gas saturation are presented.