Experimental and Theoretical Study on Two-Phase Flow through Porous Media ofTight Gas Reservoirs. Final Report, August 1988-August 1991

摘要

A history match for gas and water production from Travis Peak formation using theauthors' numerical simulator was performed. Their sensitivity analysis on the flow and reservoir parameters showed that interfacial forces between gas, water and the porous medium are very sensitive parameters in the prediction of gas and water production from gas reservoirs. A physical model with a high level of accuracy in very low flow measurements and two kinds of coreholders was constructed. Based on the authors' petrographic measurements, three categories of tight sands were identified: grain supported pores; slot and solution pores; and matrix supported grains. Gas, liquid, and two-phase flow rate data through grain supported pores, and slot and solution pore types of tight sand samples were taken at different overburden pressures and pressure drops. The data were analyzed using non-Darcy equations and the permeability and other flow parameters were calculated. A surface capillary pressure between gas and water in the entrance to core samples and inside fractures was discovered. Three two-phase flow regimes were identified. For the first time in the literature, imbibition runs were conducted for tight sand samples. Because several days of time are required for steady state data, a reliable procedure for taking transient data was developed. The transient data will save a significant amount of time and expense.