Journal of Petroleum Science and Engineering 77 (2011) 93 – 103
Prediction of gas hydrate formation condition in the presence of thermodynamic
inhibitors with the Elliott – Suresh – Donohue Equation of State
Hamed Tavasoli, Farzaneh Feyzi ⁎ , Mohammad Reza Dehghani, Farzad Alavi
Thermodynamics Research Laboratory, School of Chemical Engineering, Iran University of Science and Technology, Tehran 16846-13114, Iran
a b s t r a c t
Elliott – Suresh – Donohue (ESD) equation of state (EOS) which is based on thermodynamic perturbation theory
and uses the Wertheim association contribution to account for association interactions, is applied to predict
hydrate formation conditions in the presence and absence of thermodynamic inhibitors. The ESD EOS is coupled
with the van derWaals – Platteuw model. Methane, ethane, propane, nitrogen, carbon dioxide, n-butane and isobutane
are considered as gas components and methanol, ethanol, and mono-ethylene glycol (MEG) are
thermodynamic inhibitors considered to be present in the aqueous phase. Different cases of single gas and gas
mixtures in pure water and in a solution of water and an inhibitor are considered. To achieve more accurate
results, binary interaction coef fi cients are adjusted as a linear function of temperature. Generally, with regard to
the results obtained in various cases, it is shown that the application of the ESD EOS in predicting hydrate
formation conditions leads to accurate and acceptable results.
© 2011 Elsevier B.V. All rights reserved.
Keywords: hydrate formation; gas mixture; inhibitors; SD EOS; fl ash calculation
