等温吸附过程中不同煤体结构煤能量变化规律

Study on energy variation of different coal-body structure coals in the process of isothermal adsorption

煤吸附甲烷的过程中总是伴随动能及热量的变化,能量的变化是吸附的内在动力。对反映等温吸附过程中能量变化的相关特征参数的计算进行了推导,通过不同煤体结构煤的等温吸附实验,得到了不同温度下的相关吸附数据,计算出了不同煤体结构煤吸附甲烷过程中的能量变化值,并讨论了吸附过程中能量变化的微观机制。研究表明,糜棱结构煤的吸附能力最强,其次为碎粒结构煤、碎裂结构煤和原生结构煤;吸附势随吸附空间的增大而减小,吸附首先在微孔孔隙中进行,微孔的吸附势远大于中孔大孔的吸附势;吸附势和表面自由能总降低值的规律表现为糜棱结构煤>碎粒结构煤>碎裂结构煤>原生结构煤,揭示了煤吸附甲烷过程中的能量控制机理。

The variations of kinetic energy and heat always occur in the process of coal adsorption to methane,and it is the internal dynamic of adsorption. Calculation of parameters related to the energy changes on the isothermal adsorption process were deduced. Data acquired from isothermal adsorption experiment were used to calculate the energy change on the adsorption process of coals with different coal-body structure at different temperatures,and the mechanism of energy change in the adsorption processes was discussed. Studies showed that mylonitized coals possessthe strongest adsorption capacity,then followed by granulated coals,cataclastic coals,and intact coals. Adsorption potential decreases with the increase of adsorption space,and the adsorption potential in microporesis much greater than that in mesopores and macropores,which explain the adsorption process first occurs in micropores. The adsorption potential and cumulative reduction value of surface free energy follow the rule: mylonitized coals > granulated coals > cataclastic coals> intact coals,Energy variation mechanisms in the process of coal methane adsorption was revealed.