Performance Degradation of the Monoethylene Glycol Regeneration Process in the Presence of Electrolytes: Pilot-Scale Experiments and Dynamic Simulations

Safe production of natural gas from offshore gas fields would rely on the injection and regeneration of monoethylene glycol (MEG) to inhibit hydrate formation as well as corrosion and scale issues in subsea flowlines. In this study, we investigated the solubilities of NaCl and the vapor pressure of aqueous MEG solutions experimentally with a laboratory-scale apparatus. A thermodynamic model adopting the electrolyte NRTL-RK was developed using newly obtained experimental data and by adjusting binary interaction parameters. Then, we constructed and operated the pilot-scale MEG regeneration plant with a feed flow rate capacity of 200 kg/h to investigate the concentration of MEG solution. We varied the reboiler temperature at the bottom of the packed distillation column and the concentration of NaCl in the feed stream. It was observed that the MEG concentration decreased with decreasing rebo…