Saline water and organic inhibitors have considerable effects on preventing the formation of clathrate hydrates in gas and oil industries. The purpose of this study was to demonstrate a model that is capable of estimating the effects of NaCl, KCl, CaCl 2 and methanol aqueous solutions on the equilibrium disso- ciation conditions of pure and gas mixture hydrates in wide ranges of pressure and temperature. The e-NRTL activity coefficient model is employed to describe the non-ideally of the liquid/aqueous phase. The solid solution theory of van der Waals and Platteeuw is applied to characterize the hydrate phase. The gas phase is described by the Peng-Robinson (PR) equation of state. No adjusting or fitting param- eter is used. A comprehensive evaluation of the estimated values and literature data reveals the great accuracy of this model. To give a definite opinion, the obtained results of the proposed model were com- pared to experimental data and the results of four other thermodynamic models where the e-NRTL based model exhibits the least average absolute deviation ( AAD ). The average AAD of the e-NRTL based model results over 828 experimental data points was determined to be 0.59 K, which demonstrates an excellent agreement between the experimental data and the predicted/estimated values.
|Journal||Fluid Phase Equilibria|
|Publication status||Published - 2021|