An accurate numerical approach for predicting solubilities of hydrocarbons in hydrate inhibitors

Significant amount of work has been performed in order to determine the solubility of light hydrocarbons (methane and ethane) in the most commonly used hydrate inhibitors (such as methanol and ethylene glycol) at various temperatures and pressures. These solubility data have been compiled and correlated. In most cases, however, the current models may not be sufficient if accurate predictions are needed. The aim of this study is to present a numerical method for accurate prediction of solubilities of light hydrocarbons in methanol and ethylene glycol (at different weight percentages in water) as a function of reduced partial pressure and reduced temperature. The predictions from the proposed method have been compared with reported experimental data and found good agreement with average absolute deviation being less than 1.6% It was also found that this method is more accurate than conventional thermodynamical approaches (in particular, the NRTL model with average deviations of 20 percent) in predicting the solubilities of light alkanes in hydrate inhibitors.