Chrastil-Type Approach for Representation of Glycol Loss in Gaseous System
Résumé
Glycols are generally used to adjust the water dew-point in natural gas processes to avoid gas hydrate/ice/condensate formation. Their vaporization loss in gaseous systems may happen regularly in the petroleum industry. Glycols have very low solubility in the gas phase and because of difficulty of the corresponding measurement, few sets of experimental data are available in open literature and may not be fully satisfactory. In a previous work, we performed thermodynamic consistency tests in order to prepare reliable data sets for modeling purposes. Application of four widely used correlations in supercritical fluid industry, including the original Chrastil, Adachi and Lu, del Valle and Aguilera, and Mendez-Santiago and Teja, in which the effects of temperature, density of gas (solvent), and pressures on the solubility of glycol are generally taken into account, are investigated to represent the corresponding solubility of ethylene glycol and triethylene glycol in supercritical methane and carbon dioxide between 298.15 and 333.15 K and between 1.606 and 22.06 MPa. It is found that the absolute average deviations (AAD %) of the evaluated glycols solubility by the aforementioned equations from 57 investigated experimental values are around 27%, 18%, 31%, and 17%, respectively.