Predicting Methane Hydrate Equilibrium Conditions in Ethylene Glycol and NaCl/KCl/CaCl2 Aqueous Solutions by Water Activity Measurement

Equilibrium condition is the base of the study of gas hydrate production, prevention, and utilization. A rapid and accurate method of predicting gas hydrate equilibrium conditions is of great significance. In this work, a convenient and universal gas hydrate equilibrium conditions prediction method based on water activity measurement is proposed. The performance of the new method is tested for methane hydrate in an ethylene glycol (EG) (19.16 wt %) solution and in EG (5.77-35.00 wt %) + NaCl (3.77-15.01 wt %)/CaCl2 (14.00-18.00 wt %)/KCl (8.00-10.00 wt %) solutions at 259.3-287.8 K. In comparison with that in the literature, the new method predicted results are in good agreement with the experimental data. The new method might provide an easy option for gas hydrate equilibrium condition determination.

Automated summary

This research presents a rapid and accurate method for predicting gas hydrate equilibrium conditions based on water activity measurement, which is tested and proven to be reliable and effective through experiments.