Prediction of Methane and Ethane Gas Hydrate Formation and Their Mixture in a Porous Medium

The purpose of this paper is to study the thermodynamic modeling of the conditions for methane and ethane gas hydrate formation and their mixtures in a porous and non-porous environment. In this paper, the Van der Waals- Platteeuw thermodynamic model was used for prediction of gas hydrate formation conditions. Also, the SRK and PTV equations of state were used for calculations of driving force. In this research, the results of thermodynamic modeling in a porous were compared with the non-porous environment and laboratory data in the literature. Studies have shown that the results of the modeling are in good agreement with the laboratory data and the percentage of errors is low. The results also showed that with increasing pressure of porous and non-porous media, the equilibrium temperature increases. In addition, the effect of the pore diameter of porous media on the results of modeling was investigated for methane, ethane and their mixtures during gas hydrates formation. The results showed that by increasing the pressure for any size of the pore diameter of the porous medium, hydrate formation temperature increases. In addition, by increasing the pore diameter of the porous medium, hydrate formation temperature methane, ethane and their mixture increase at a constant pressure. The results also showed that the equilibrium temperature of the non-porous medium is higher than the equilibrium temperature of the non-porous medium. This shows that the hydrate formation in the porous medium has a deterrent effect and leads to lower temperatures and higher temperatures conditions for gas hydrate formation. The results showed that by increasing the percentage of methane in a porous or non-porous medium, the temperature of hydrate formation of the binary gas mixture of methane and ethane decreases.