Extended isenthalpic and/or isothermal flash calculation for hydrocarbon components that are soluble in oil, gas and water

An apparatus, comprising:

• one or more computer processors;
• and
• a memory having instructions that when executed by the one or more computer processors determine distribution of a plurality of components among a plurality of phases for a multi-component, multi-phase system including a multi-component, multi-phase fluid, the instructions including:
• instructions to determine a plurality of phase boundaries of the multi-component, multi-phase fluid and a vapor-liquid equilibrium (VLE) based on a plurality of geophysical parameters associated with an oilfield, including instructions to determine 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, wherein applying empirical equilibrium multi-phase mole fraction ratios of the multi-component, multi-phase system that are functions of temperature and pressure only includes, for a first hydrocarbon component in the multi-component, multi-phase fluid that is soluble in liquid, water and vapor phase;
• applying a first empirical equilibrium multi-phase mole fraction ratio (K-value) for equilibrium between the liquid (L) and vapor (V) phases of the first hydrocarbon component;
• and
• applying a second empirical equilibrium multi-phase mole fraction ratio (K-value) for equilibrium between the water (A) and vapor (V) phases of the first hydrocarbon component;
• and
• instructions to predict an amount of at least one fluid component distributed in a plurality of phases of the multi-component, multi-phase system by solving a set of flash equations based on the plurality of phase boundaries.

A program product, comprising:

• a non-transitory computer readable medium;
• and
• program code stored on the non-transitory computer readable medium and configured upon execution by one or more computer processors to determine distribution of a plurality of components among a plurality of phases for a multi-component, multi-phase system including a multi-component, multi-phase fluid, the program code including:
• instructions to determine a plurality of phase boundaries of the multi-component, multi-phase fluid and a vapor-liquid equilibrium (VLE) based on a plurality of geophysical parameters associated with an oilfield, including instructions to determine 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, wherein applying empirical equilibrium multi-phase mole fraction ratios of the multi-component, multi-phase system that are functions of temperature and pressure only includes, for a first hydrocarbon component in the multi-component, multi-phase fluid that is soluble in liquid, water and vapor phases;
• applying a first empirical equilibrium multi-phase mole fraction ratio (K-value) for equilibrium between the liquid (L) and vapor (V) phases of the first hydrocarbon component;
• and
• applying a second empirical equilibrium multi-phase mole fraction ratio (K-value) for equilibrium between the water (A) and vapor (V) phases of the first hydrocarbon component;
• and
• instructions to predict an amount of at least one fluid component distributed in a plurality of phases of the multi-component, multi-phase system by solving a set of flash equations based on the plurality of phase boundaries.