EQUATIONS OF STATE FOR REPRESENTING PVT P ROPERTIES AND VAPOR-LIQUID-EQUILIBRIA OF HYDROCARBONS

A comparative study of several equations of state (EOS) derived from t he van der Waals theory was performed. The aim was to select the model s able to represent PVT properties of hydrocarbons in large pressure a nd temperature ranges. 34 hydrocarbons of various sizes and structures were selected. Experimental data of vapor liquid equilibria (vapor pr essures and liquid volumes) and PVT properties of compressed fluids we re systematically compared with results obtained using selected EOS. I t was shown that only the complex EOS (especially the COR equation) ar e able to represent volumetric properties in wide temperature and pres ssure ranges, the critical region included.