A Fortran Computer Program for Phase Equilibria and Thermodynamic Properties Using the Benedict-Webb-Rubin Equation

摘要

A robust interactive computer program has been developed for solving the eight constant Benedict-Webb-Rubin equation of state. The program requires specification of system pressure and liquid composition and predicts multicomponent vapour-liquid equilibria, liquid and vapour phase densities and enthalpy departures. For mixtures of light hydrocarbons at conditions well below critical, the difference between computed and experimental vapour mole fraction is generally less than 0,05. Computed equilibrium temperature is not consistently accurate and, in the region of the critical point, single phase systems are predicted below the mixture critical pressure. Unsatisfactory equilibrium predictions are produced for systems containing hydrogen or non-hydrocarbons. Development of an improved version using eleven constants is recommended although these constants are available only for about 20 compounds.