Gas Adsorption and Desorption Performance of Coal with Different Degree of Metamorphism

Starting from the gas pore stress of coal, the low-temperature nitrogen adsorption test is used to investigate the micropore characteristics of coal with different metamorphic degrees and its influence on gas adsorption/desorption, and to clarify the relationship between the initial rate of gas adsorption and desorption in coal and the pore stress. The experimental study was carried out by using self-built test equipment to simulate the actual formation. The results showed that: as the degree of coal metamorphism increases; the initial rate of gas adsorption and desorption is proportional to the pore stress of the coal seam, and the desorption capacity is stronger than the adsorption capacity within the same experimental period. In the same experiment time, the desorption capacity is stronger than the adsorption capacity, and the pore stress has a linear relationship with the initial rate of adsorption and desorption.