Numerical modeling of steam injection in heavy oil reservoirs

In this communication, a three-dimensional, three-phase numerical model is presented for simulation of steam injection in heavy oil reservoirs. Formulation details, numerical solution method, and computational results are presented. The model includes the effects of three-phase relative permeability, capillary pressure, and temperature and pressure-dependent fluid properties. Interphase mass transfer of water-steam is allowed, but the oil is assumed nonvolatile and the hydrocarbon gas is insoluble in liquid phases. The three-phase mass balance and the energy balance equations are solved simultaneously using finite difference method. Some steam injection laboratory data are used for studying the accuracy of this model. Comprehensive and comparative studies together with extensive sensitivity analysis among various important parameters are conducted to understand steam injection performance in the heavy oil reservoir. This work indicates that steam injection can improve oil recovery from almost zero up to nearly 60% during a fixed period of time. In addition, it shows that only 30% of OOIP can be recovered by hot water injection method. The results demonstrate that there is an optimum time for oil production that is determined according to the flow of oil production and steam-oil ratio (SOR).