Abstract
The oil and gas industry has faced new challenges, especially since discovering and exploring Brazilian pre-salt reserves. The current dehydration processes, imperative for gas processing and distribution, result in relevant solvent losses or are too expensive, space-demanding, or both. Molecular simulations have been among the preferred approaches in the last few years. Although computationally demanding, their versatility, predictive character, and accuracy make them an asset for many tasks. As the required time can yet be a hindrance when working with molecular simulations, the Damped Shifted Force (DSF) method can be an exciting option for a faster calculation of the electrostatic interactions, in contrast with the more popular Ewald methods, more rigorous and time-consuming. The present work presents Monte Carlo simulations using the DSF method to predict the vapor-liquid equilibria of binary mixtures containing some of the natural gas main components: CH4, CO2, and H2O. The results were compared to experimental data and other Monte Carlo simulations found in the literature to check whether the DSF method is a reliable alternative for natural gas systems. The comparison showed that DSF simulations had comparable accuracy to other Monte Carlo simulations (including Ewald ones) and provided predictions close to experimental data.