A correlation for thermodynamic properties of heavy fossil-fuel fractions

Abstract

A correlation is developed for calculation of thermodynamic properties of heavy fossil fuels, based on a recent version of the perturbed-hard-chain equation of state. Since the correlation does not require experimental vapor pressures or densities as input data, it is useful for heavy fossil fuels where vapor pressures and densities are difficult or impossible to measure. For fossil-fuel fractions, equation-of-state parameters are found from approximate molecular-structure (characterization) data coupled with a calibration based on pure-component (model-compound) data. Interaction parameters are given for mixtures of fossil fuels with methane, ethane, carbon dioxide, hydrogen, and hydrogen sulfide. While the correlation presented here is useful for calculating vapor-liquid equilibria, it is not intended for conventional fossil fuels, where other correlations are satisfactory. Instead, it is intended for heavy fossil fuels where conventional correlations are often not reliable and where the usual input data are often unavailable.