Search

The increase in methane pressure in a sealed thermobaric flask containing gas-bearing coal is investigated in laboratory experiments. An analogous process in a sealed cylindrical borehole drilled in a coal bed through a rock plug is analyzed. This behavior is mathematically described. It is the result of two opposing processes. First, methane is desorbed from fine coal particles or from coal in the bed close to the borehole. That gives rise to methane pressure in the available free space (within the flask or the borehole). With increase in that pressure, the methane is resorbed into the coal. Thus, desorption is slowed and ultimately stops. By analogy with electromagnetic induction, this process may be called desorptional methane induction. The quantitative characteristics of desorptional methane induction are determined by the degree of gas saturation of the coal and the total volume under consideration. [ABSTRACT FROM AUTHOR]