THE INFLUENCE OF GREAT DEPTHS ON THE CONDITIONS ACTIVATING THE DESORPTION OF ADSORBED METHANE GENERATED IN A VIRGIN COAL SEAM

It is generally accepted that when a coal seam is in a virgin rock massif for millions of years under the influence of rock pressure, its state is characterized by the absence of any physical processes in it. In this article, it is stated that in reality, in these conditions relaxation processes can occur. These processes are caused by conformational rearrangements in the coal microstructure. They, in turn, create conditions for breaking the sorption equilibrium of adsorbed methane in coal due to the distance of methane molecules from the microstructure of the coal medium when the interlayer distances in the graphite-like layers of the coal seam expand. The parameters are established, which determine the duration of the coal molecular structure relaxation; characterize the ability of the structure to deform, and the conditions under which the most significant changes occur. It is shown that the main parameters that affect the activation of desorption of adsorbed methane in a virgin coal seam are the energy of conformational rearrangement activation, the temperature of the seam, and the interlayer distance in the graphite-like layers. As a result of the research, it was found that with an increase in the depth of the virgin coal seam, relaxation processes in it occur faster. These processes are caused by conformational rearrangements in the coal microstructure. They, in turn, create conditions for breaking the sorption equilibrium of adsorbed methane in coal due to the distance of methane molecules from the microstructure of the coal medium when the interlayer distances in the graphite-like layers of the coal seam expand. The novelty of this research is in the establishment of the fact that with an increase in the depth of the virgin coal seam, all physical and mechanical processes associated with changes in the molecular structure of coal occur faster. At the same time, the energy of activation of these processes realization is less, including the energy of activation of adsorbed methane desorption.