Rigorously Universal Methodology of Volume Translation for Cubic Equations of State

Abstract

To model systems typically found in hydrocarbon production problems and the chemical industry, there are three basic types of calculations are required: phase equilibria, volumetric behavior, and thermophysical properties. Since 1972, cubic equations of state (CEoS) have shown surprising capabilities in the prediction of the phase equilibria of complex nonpolar systems. However, the prediction of the liquid volumes from cubic equations of state, despite the recently important advances in CEoS/AE mixing rules, still remains the weak point of this type of equations. A rigorous, universal, but simple methodology without introducing any regressed parameters is proposed for the volume translation for all types of cubic equation of state. The proposed methodology applies to not only defined components but also petroleum fractions. The translated cubic equations of state reproduce almost exactly the liquid density over the entire temperature range from the triple point to the critical point.