چكيده به لاتين
Abstract:
Recently based on many application of hydrates, efforts have been dedicated to investigation of this phenomena formation’s equilibrium conditions. For improvement of hydrate formation conditions usually we use additives like tetra¬butyl ¬ammonium ¬bromide salt. The purpose of this work is thermodynamic modeling of formation equilibrium conditions of methane semi-clathrate hydrate in presence of TBAB salt aqueous solution. For definition of thermodynamic equilibrium, equality of water fugacity in water phase and hydrate phase have been used. For modelling of hydrate phase, the van der Waals–Platteeuw modified solid solution theory have been used. Extended UNIQUAC activity model for calculation activity coefficients of components in liquid phase and PHSC equation of state for calculation of fugacity of methane in gas phase have been used. Results of calculations and comparison with experimental data and other thermodynamic models show that presented model more accurately predicts formation condition of methane semi-clathrate hydrate in presence of TBAB salt aqueous solution. Average absolute relative deviation percent (AARD%) for presented model is between 1.455 – 13.159 percent and average of error is 5.385 percent.
Keywords: semi-clathrate hydrate, PHSC EOS, Extended UNIQUAC, Thermodynamic modeling, TBAB
