Method of operating an oil/gas facility based on accurate determination of capillary pressure and interfacial tension

A computerized method and system for of operating an oil/gas facility for processing oil and gas from a reservoir. The method includes steps of receiving input data concerning condensate phase and gas phase components in the reservoir, the input data characterizing both phase components, determining a pore capillary pressure of the reservoir based on the received input data which characterizes the phase components, determining PVT parameters of the reservoir phase components based on the determined pore capillary pressure, and controlling a setting of the oil/gas facility based on the determined PVT parameters of the reservoir phase components.