A Method for Predicting the Equilibrium Gas Phase Water Content in Gas-Hydrate Equilibrium

Abstract

Recent experimental data on the equilibrium water content of the gas phase in gas-hydrate equilibrium have been used to develop expressions for the fugacity of water over the unfilled hydrate lattice as a function of pressure and temperature, for both Structure I and Structure II hydrates. The predicted water content of the gas phase using these equations agrees very well with the experimental values and for Structure II hydrates indicates that the parameters in the equations are independent of composition. The general applicability of the proposed equations to other mixtures can only be evaluated as additional data become available.

A New Approach for Multicomponent Vapor Solid Equilibrium Calculations in Gas Hydrate Formation

“…Their results complement partial data sets from other laboratories and provide new results in the region of 193-260 K. [8] Ng and Robinson used experimental data on the equilibrium water content of the gas phase in gas-hydrate equilibrium to develop expressions for the fugacity of water over the unfilled hydrate lattice as a function of pressure and temperature, for both Structure I and Structure I1 hydrates. The predicted water content of the gas phase using these equations agrees with the experimental values and for Structure II hydrates indicates that the parameters in the equations are independent of composition [9].…”

Clathrate hydrates

“…However, experimental data and computational methods have been presented by Kobayashi, Sloan, and co-workers (Sloan et al, 1976(Sloan et al, , 1987Sloan, 1982Sloan, , 1990aKobayashi, 1982, 1987). Ng and Robinson (1980) also presented a method for the determination of the water content of a gas.…”

Sixty Years of the van der Waals and Platteeuw Model for Clathrate Hydrates—A Critical Review from Its Statistical Thermodynamic Basis to Its Extensions and Applications

“…Afterward, Ng and Robinson 103 extended this methodology to simple and mixed gas hydrates of both structure sI and sII in 1980. An agglutination of the physical aspects was performed, as the authors used an empirical correlation for the water fugacity in the empty hydrate, as a function of temperature and pressure, avoiding the use of separate contributions for the fugacity coefficient, the vapor pressure correlation and the Poynting factor.…”