Study On The Influence Of Coal Rupture Degree On Gas Adsorption And Desorption

In this paper,the gas adsorption and desorption laws of coal samples under different uniaxial compression stages are studied experimentally.The numerical simulation results show the development of pore-fracture structure in the process of failure.Experimental results show:1)The gas adsorption capacity of the coal sample in the complete state is the largest,the elastic point stage,the yield point stage,the peak point stage and the gas adsorption amount in the crushing stage are not much different,but obviously lower than the gas adsorption amount in the complete state;2)From the complete state of coal sample to the crushing stage,the change trend of desorption velocity of coal sample is "U" shape,the complete state,the peak point stage and the gas desorption velocity in the crushing stage are larger.Elastic phase stage,the yield stage of the desorption of the initial velocity is small;3)With the increase of gas pressure,the adsorption capacity of coal increases,but the increment rate of gas adsorption increases gradually;4)With the increase of the gas pressure,the time required for the coal to reach the adsorption equilibrium is prolonged;5)The acoustic emission characteristics of the coal sample are consistent with the stress-strain curves,which can characterize the changes of the pore-fissure structure within the coal during the coal-like failure process.