Prediction of methane and carbon dioxide solubilities for the CH4 + CO2 + H2O system under hydrate–liquid–vapor equilibrium

Three phase, hydrate–liquid water–vapor (H–Lw–V) equilibrium conditions for the CH4 + CO2 + H2O system have been predicted. The modelling is based on the Trebble–Bishnoi equation of state along with the models by van der Waals and Platteeuw and Holder. The predictions are demonstrated for the temperature region between 274 and 280 K and the pressure region between 1.4 and 5 MPa. The predicted vapor mole fraction of carbon dioxide has an AARE of 10.2% and the predicted solubilities for methane and carbon dioxide in the liquid phase have an AARE of 9.0% and 3.2%, respectively. This is the first study to predict the solubility of methane and carbon dioxide in the liquid phase for the CH4 + CO2 + H2O system under H–Lw–V equilibrium.

► The liquid and gas phase compositions for CH4 + CO2 +H2O under H–Lw–V eqm are predicted. ► This is the first work to predict liquid solubility for a mixed hydrate system. ► Work is based on Trebble–Bishnoi EOS, van der Waals and Platteeauw and Holder models. ► All model parameters used in the predictions are independently optimized. ► The model predictions are found to fit the data.