Experimental Measurements and Thermodynamic Modeling of CH4 + H2S + MEG Hydrate Phase-Equilibrium Conditions at 6.2–12.3 MPa

• Published in: Journal of chemical and engineering data 2022-09, Vol.67 (9), p.2384-2392
• Main Authors: Aminolroayaei, Mohammad Ali, Taheri Rizi, Zahra, Mohammad-Taheri, Mahboobeh, Kamran Pirzaman, Arash, Dehbandi Baladehi, Mojtaba, Ehsani, Mohammad Reza
• Format: Article
• Language: English
• Subjects: Vapor-Liquid Equilibria and Supercritical Fluid Equilibria
• ISSN: 0021-9568; 1520-5134
• DOI: 10.1021/acs.jced.2c00111

This work generated experimental gas hydrate equilibrium data with a gas composition containing CH4 (99 mol fraction) + H2S (1 mol fraction) similar to the field. The stepwise heating isochoric pressure search method was used for uninhibited and inhibited systems with mono-ethylene glycol (MEG). Thermodynamic consistency of the experimental data in the presence of MEG was performed for each concentration. Based on the three assessments presented, the experimental data consistency was good for 15 and 20 wt % and moderate for 10 wt %. Finally, an in-house model was developed based on the experimental data. The proposed model with the given assumptions and limitations showed 1–2% more deviation than HydraFlash predicted for the system containing 10–20 wt % MEG. In this work, the prediction of HydraFlash was the one with the lowest average absolute relative deviation in pressure (AARDP) % between different equations of state available in the software for each system. Hence, the deviation range of AARDP % was acceptable for an in-house model to be developed for the gas industry compared to the commercial software.