Earth’s Cryosphere, 2017, Vol. XXI, No. 5, p. 46-52
KINETICS GROWTH OF GAS HYDRATE OF FREON-12 DURING THERMAL CYCLING OF SAMPLE
A.G. Zavodovsky1, M.Sh. Madygulov1,2, A.M. Reshetnikov1,2
1Earth Cryosphere Institute, Tyumen Scientific Centre SB RAS,
86, Malygina str., Tyumen, 625026, Russia; zag-2-57@yandex.ru
2Tyumen Industrial University, 38, Volodarskogo str., Tyumen, 625000, Russia
The article presents the results of experiments involving differential thermal analysis to study the kinetics of growth of a freon-12 hydrate sample at the cyclic change in the temperature in the range of 263–276 K. The radial growth rate of the gas hydrate cake initially formed at the temperature of 263 K on ice granules with the mean size of 150 μm has been measured. Comparative analysis has been carried out for the growth rate of the hydrate among the samples, depending on the presence of water or ice in them. It has been found that hydrate growth is determined by the diffusion properties of the inhomogeneous gas hydrate cake: there are inclusions of either water or ice in it, depending on the sample temperature. The main factors have been identified to contribute to the maximum content of gas hydrate in a sample.
Growth kinetics, disperse ice, gas hydrate, differential thermal analysis, crystallization, diffusion