Abstract: A method for simulating a microemulsion system in a chemical enhanced oil recovery process is disclosed. The method includes receiving a geological model of a subsurface reservoir that defines a grid having a plurality of cells, determining a surfactant concentration for each cell based on a volume of surfactant and a volume of water within the cell and independently from a volume of oil in the cell, and simulating fluids flowing in the subsurface reservoir. Results from simulation can be used to optimize a chemical enhanced oil recovery process in a subsurface reservoir.

Abstract: A method, apparatus, and program product to determine distribution of a plurality of components amongst a plurality of phases for a multi-component, multi-phase system including a multi-component, multi-phase fluid. A plurality of phase boundaries of the multi-component, multi-phase fluid and a vapor-liquid equilibrium (VLE) are determined based on a plurality of geophysical parameters associated with an oilfield and using one or more computer processors, including by determining hydrocarbon partitioning in a water phase, based in part on applying empirical equilibrium multi-phase mole fraction ratios (K-values) of the multi-component, multi-phase system that are functions of temperature and pressure only. In addition, an amount of at least one fluid component distributed in a plurality of phases of the multi-component, multi-phase system is predicted by solving a set of flash equations with the one or more computer processors based on the plurality of phase boundaries.

Abstract: A method for simulating a microemulsion system in a chemical enhanced oil recovery process is disclosed. The method includes receiving a geological model of a subsurface reservoir that defines a grid having a plurality of cells, determining a surfactant concentration for each cell based on a volume of surfactant and a volume of water within the cell and independently from a volume of oil in the cell, and simulating fluids flowing in the subsurface reservoir. Results from simulation can be used to optimize a chemical enhanced oil recovery process in a subsurface reservoir.

Abstract: A method, apparatus, and program product to determine distribution of a plurality of components amongst a plurality of phases for a multi-component, multi-phase system including a multi-component, multi-phase fluid. A plurality of phase boundaries of the multi-component, multi-phase fluid and a vapor-liquid equilibrium (VLE) are determined based on a plurality of geophysical parameters associated with an oilfield and using one or more computer processors, including by determining hydrocarbon partitioning in a water phase, based in part on applying empirical equilibrium multi-phase mole fraction ratios (K-values) of the multi-component, multi-phase system that are functions of temperature and pressure only. In addition, an amount of at least one fluid component distributed in a plurality of phases of the multi-component, multi-phase system is predicted by solving a set of flash equations with the one or more computer processors based on the plurality of phase boundaries.