To explore the pore structure and adsorption characteristics of deep coal seams, Shanxi Liulin coal samples and Henan Pingdingshan coal samples were selected as research objects. Based on high-pressure mercury intrusion, low-temperature nitrogen adsorption, and high-pressure capacity method, the pore distribution and changes in deep coal seams were analyzed, and the influence of pore structure on adsorption was investigated. The adsorption characteristics of deep coal seams under different temperatures and pressures were revealed, and an adsorption model of deep coal seams under the synergistic effect of temperature pressure pore was established. The results show that according to the mercury advance and retreat curve, the hysteresis degree of the mercury advance and retreat curve in deep coal seams decreases, semi enclosed pores increase, and the connectivity of coal deteriorates; According to the nitrogen adsorption and desorption curves, it can be seen that the adsorption curve of deep coal seams shows a trend of initially increasing, briefly stabilizing in the middle stage, and then increasing in the later stage; There is a clear linear relationship between Langmuir volume (V) and micropore volume and bet; The Langmuir pressure (P) is related to the volume and specific surface area of mesopores, indicating that the microporous structure controls the final adsorption capacity of coal for methane, and the mesoporous structure affects the morphological characteristics of methane adsorption isotherms. Moreover, the adsorption capacity of coal for methane is mainly manifested by the microporous structure below 10nm; The established adsorption model under the synergistic effect of temperature pressure pore can well characterize the adsorption characteristics of deep coal, and the adsorption amount of deep coal seams shows a downward trend with increasing depth.
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