Dynamic characteristics and model optimization of gas adsorption in loaded coal
YAN Jiangwei;RONG Tianke;FENG Xiang;SUN Rui;LI Juntong
河南省瓦斯地质与瓦斯治理重点实验室−省部共建国家重点实验室培育基地河南理工大学 安全科学与工程学院煤炭安全生产与清洁高效利用省部共建协同创新中心安徽江南化工股份有限公司
随着煤矿开采向深部延伸,地应力对煤层瓦斯赋存状态和赋存规律的影响作用愈加明显,为了更好地研究受载煤体的瓦斯吸附动力学特性,开展了煤样在不同围压、轴压下的等温吸附试验,分别采用准一级、准二级、Elovich以及Bangham吸附动力学模型对试验结果进行拟合和分析,探讨了受载煤体的吸附动力学特征,为进一步探索深部煤层瓦斯赋存状态及规律提供了理论依据。研究表明:随着吸附的进行,吸附量增大且变化趋势逐渐放缓,瓦斯吸附速率逐渐降低;外加荷载越大,瓦斯平衡吸附量减小;4种吸附动力学模型中,Bangham动力学模型能更好地描述围压影响下的煤体瓦斯吸附动力学特征,准一级吸附动力学模型能更好地描述轴压影响下的煤体瓦斯吸附动力学特征;平衡吸附量参数同外加荷载呈负幂函数关系,吸附速率参数同外加荷载呈负相关关系。
With the deep extension of coal mine mining, the influence of ground on occurrence state and regularity of coal seam gas is more and more obvious. In order to better study the kinetic characteristics of gas adsorption in the loaded coal, isothermal adsorption experiments were carried out in coal samples under different confining pressures and axial pressures. The quasi-first-order, quasi-second-order, Elovich and Banghamadsorption kinetic models were used to fit and analyze the experimental results, and the adsorption kinetic characteristics and influence mechanism of loaded coal were discussed. It provides a theoretical basis for further exploration of gas occurrence state and law in deep coal seam. Results indicate that as the adsorption progresses, the adsorption capacity increases and the trend gradually slows down and the rate of change of gas adsorption capacity is gradually reduced. The larger the applied load is, the smaller the equilibrium adsorption capacity of gas is. Among the four adsorption kinetic models, the Bangham kinetic model can better describe the dynamic characteristics of coal gas adsorption under the influence of confining pressure, and the quasi-first-order adsorption kinetic model can better describe the dynamic characteristics of coal gas adsorption under the influence of axial pressure. The equilibrium adsorption capacity parameter has a negative power function relationship with confining pressure and axial pressure. The adsorption rate parameters are negatively correlated with the applied load.
loaded coal;gas adsorption;kinetic model;model optimization;characteristic analysis
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会