不同煤阶煤样在地热水环境中的理化特征研究OA

To elucidate the structural evolution and interfacial reactivity of coals with different metamorphic degrees under geothermal conditions,three representative coal samples,gas coal(GC),coking coal(CC)and anthracite(ANT),were subjected to water-coal interaction experiments at 25℃and 50℃.Scanning electron microscopy(SEM),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),and contact angle measurements were employed to systematically characterize variations in surface morphology,functional groups,and hydrophilicity.The results showed that geothermal treatment markedly facilitated the transformation of coal sur-faces from compact to porous structures,with more pronounced pore development and crack propagation in low-rank coals.With the increase of temperature,the content of polar functional groups such as C—O and C＝O increases,the proportion of C—C structure decreases,the O/C ratio has significantly increased,it indicates that the coupled heat-water effect enhances the oxidation and polarization processes on the coal surface.Contact angle measurements further revealed that coal hydrophilicity was significantly enhanced with temperature,particularly for coking and an-thracite coals,indicating that geothermal conditions strengthen water-coal interfacial reactions through a synergistic mechanism of"structural loosening-functional group oxidation-hydrophilicity enhancement.This study provides a mo-lecular-level understanding and theoretical foundation for quantitatively describing coal-water reactivity,DOM release dynamics,and subsurface carbon migration processes in geothermal environments of deep coal seams.