Application of Esd and Pr+Wong Sandler Mixing Rule Equations of State To Study Methane Hydrate Formation in the Presence of Different Inhibitors

Due to existing inhibitors in capable hydrate forming mixture, extra intermolecular interactions affect hydrate formation conditions. predicting hydrate formation conditions is not possible without considering these interactions. in this work, two different equations of state (eos) are used and compared to predict the hydrate formation pressure in the presence of inhibitors. the eoss applied are elliout-suresh- donohue (esd) eos and peng-robinson (pr) eos with wong-sandler (ws) mixing rules. parrish and prausnitz hydrate formation algorithm is coupled with flash calculations to predict hydrate formation pressure at different temperatures and different concentrations of polar inhibitors. pure and binary interaction parameters are obtained for esd eos. on the other hand, necessary unknown parameters which should be used in applying pr with ws mixing rules are adjusted on experimental hydrate formation condition data. number of water hydrogen bonding sites, which are used in calculations, is also determined. hydrate formation pressure for different polar inhibitors (methanol, ethanol, 1-propanol, ethylene glycol and diethylene glycol) in various concentrations is predicted with applying the two eoss. to investigate the ability of the esd eos in predicting gas mixture hydrate formation conditions, four different gas mixtures are considered in the absence and presence of hydrate inhibitor. generally, esd eos shows better results in comparison with pr eos + ws mixing rule.