为研究CO2、N2在烟煤与无烟煤中的吸附特征,对烟煤(C201H170N2O3S)分子模型和无烟煤(C182H112O7)分子模型在不同温度和不同压力下进行了巨正则蒙特卡洛模拟和分子动力学模拟。结果表明,CO2在烟煤与无烟煤分子中的吸附量和吸附速率均大于N2;两种气体的吸附热都小于40 kJ/ mol,对于压力和温度的变化并不敏感。另外,CO2 和N2 更容易吸附在含氧官能团和苯环附近。两种气体在煤中的扩散能力大小顺序为N2 > CO2,这是由于CO2 具有更强的吸附能力。在吸附过程中CO2对温度变化十分敏感,故高温采空区可运用交替注气方式更能有效防止煤炭自燃,研究结果对采空区防灭火具有实际意义。

The molecular models of bituminous coal (C201H170N2O3S) and anthracite (C182H112O7) were sim⁃ulated by grand canonical Monte Carlo simulation and molecular dynamics simulation at different temperaturesand pressures. The results show that the adsorption capacity and adsorption rate of CO2 in bituminous coal andanthracite molecules are greater than that of N2. The adsorption heat of both gases is less than 40 kJ/ mol,which is not sensitive to the changes of pressure and temperature. In addition, the CO2 and N2 are easier to beadsorbed near oxygen-containing functional groups and benzene rings. The order of diffusion capacity of CO2and N2 in coal is N2 >CO2, which is due to the stronger adsorption capacity of CO2. Temperature change has asignificant impact on the adsorption amount of carbon dioxide in coal. The use of alternating gas injection inhigh-temperature goaf areas is more effective in preventing coal spontaneous combustion, and the research re⁃sults have practical significance for preventing and extinguishing fire in goaf areas.