On the Theory of Injection of a Cold Gas into a Snow Mass Accompanied by Hydrate Formation

The problem on the formation of a gas hydrate in a snow mass, whose pores in the initial state are saturated with a gas, in the process of injection of the same gas into this mass was considered. Self-similar solutions defining the distributions of the main parameters of the snow mass (its temperature, pressure, and phase saturation) have been constructed. It is shown that, depending on the initial thermobaric state of the snow–gas system and the intensity of injection of the gas into the snow mass, in its filtration region there can arise three characteristic zones: a near zone in which the snow turned completely into the hydrate state and which, consequently, is saturated with the gas and the hydrate, an intermediate zone in which the gas, the snow, and the hydrate are at phase equilibrium, and a far zone filled with the gas and snow. It was established that the extension of the three-dimensional zone of hydrate formation in a snow mass decreases with increase in its initial snow saturation, an intermediate hydrate-formation zone of larger length arises in a snow mass with a higher permeability, and this zone is heated more intensively in a snow mass with a lower initial temperature in which, for this reason, the snow fraction at the near boundary is increased.