Glycols in natural gas – experiments , modelling and tracking

Glycols are important chemicals used in oil and gas production. Glycols are typically used for hydrate control and dehydration of natural gas. Glycols are low-volatility components, with low solubility in both gas and oil. However, operational experience shows that loss of glycols can give unwanted effects in downstream transport pipelines and process equipment. Few experimental data sets are published for glycol solubility in pressurized gases in the open literature. This paper presents experimental data for solubility of monoethylene glycol (MEG) in three gases (methane, CO2, methane+ethane) measured in the temperature range from 0 to 25 °C and pressure range from 25 to 150 bar. The experimental data are compared to the CPA-EoS. The calculations are able to match the experimental data for MEG solubility in methane and methane+ethane with good accuracy at 50 bar. At higher pressure, the deviations between the model and the experimental data increases. MEG solubility in gaseous CO2 was predicted with good accuracy for all measured points.