مسعود مفرحی

In this study hydrate equilibrium pressure for methane and carbon dioxide in the presence of pure water was calculated by GC-VTPR equation of state in the fluid phase and Chen-Guo model for hydrate phase. At the first step, to evaluate ability of GC-VTPR to model fluid phase, solubility of methane and carbon dioxide in the pure water was calculated and then combining this model with Chen-Guo for hydrate phase, the hydrate equilibrium pressure at a given temperature was calculated. For 305 hydrate equilibrium pressure data for methane and carbon dioxide, the average absolute error was 3.29%. this results show this model can be used to correlate hydrate equilibrium conditions well.