Study and Modeling of Ethane Hydrate Formation Conditions in Presence of Thermodynamic Promoter Tetrahydrofuran

Document Type : Research Article


Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, I.R. IRAN


In this work, hydrate formation conditions of ethane in the presence of THF as promoter and modeling of ethane hydrate formation were investigated. The Parrish-Prausnitz model was used because of its simplicity and accuracy, and SRK and PR equations of state were used in calculations. The mechanism of the experiment for finding the equilibrium point of hydrate formation is confliction of formation and dissociation curves. At first, pure ethane system and then system containing THF in three concentrations of 5, 8 and 10 mol% were hydrated in a stirred setup. In pure ethane system, experimental results were closer to reference results and the average error of modeling was low for both of equation of states. In the system containing THF promoter, there was more difference between experimental and modeling. The overall error of SRK equation of state was lower than PR. promotion effect of THF on ethane hydrate formation was more significant than reference additives. Also, in the concentration of 5 and 8 mol%, THF acted as a promoter but in a concentration of 10 mol%, it acted as an inhibitor.






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