Surfactant Versus Solvent Co-Injection to Improve Efficiency of Steam Assisted Bitumen and Heavy Oil Recovery Processes

摘要

In Canada, daily steam assisted bitumen and heavy oil production is about 1.5×106 barrels per day, which is predicted to increase steadily. Oil industry has spent significant effort on solvent, mostly light hydrocarbons co-injection with steam to boost bitumen mobility, therefore, production efficiency; which resulted limited commercial success. In most solvent co-injection with steam studies further reduction of already reduced bitumen viscosity by steam injection was focused, while its effect on bitumen-water interfacial tension was ignored. At our laboratory effects of surfactant (such as biodiesel) and solvent (such as pentane) on bitumen viscosity, bitumen-water interfacial tension and steam assisted gravity drainage were evaluated. Experimental data showed that bitumen recovery efficiency was reduced by solvent co-injection with steam; which is attributed that solvent addition increases bitumen-water interfacial tension, causes slip of water on bitumen and suppresses bitumen mobility, which result in counterbalancing benefits of viscosity reduction. In the present study creeping flow of two immiscible fluids, such as oil and water (condensed steam) in a capillary with no-slip and slip boundary conditions at oil-water interface is discussed to provide technical support for better understanding of solvent versus surfactant co-injection with steam for bitumen and heavy oil recovery, as well as water flooding and CHOPS and Post CHOPS processes.