Gas desorption characteristics of the high-rank intact coal and fractured coal  

作　　者：Lu Shouqing Cheng Yuanping Qin Liming Li Wei Zhou Hongxing Guo Haijun 

机构地区：[1]National Engineering Research Center of Coal Gas Control,China University of Mining & Technology [2]School of Safety Engineering,China University of Mining & Technology [3]Key Laboratory of Gas and Fire Control for Coal Mine,China University of Mining & Technology

出　　处：《International Journal of Mining Science and Technology》2015年第5期819-825,共7页矿业科学技术学报（英文版）

基　　金：provided by the National Basic Research Program of China(No.2011CB201204);the Natural Science Foundation for the Youth of China(Nos.41202118 and 51204173)

摘　　要：The objective of this work is to study the gas desorption characteristics of the high-rank intact coal and fractured coal.The gas adsorption,mercury porosimetry and gas desorption experiments were carried out in this study.Then,the theories of thermodynamics,diffusion mechanism and desorption kinetics were used to estimate the gas desorption characteristics.The results of gas adsorption experiments show that the initial isosteric adsorption heat of the intact coal is greater than that of the fractured coal,indicating that the gas molecules desorb more easily from fractured coal than intact coal.Using the mercury porosimetry,we find that the diffusion channels of fractured coal are more developed than those of intact coal.The difficult diffusion form dominates in the intact coal during the gas diffusing,while the easy diffusion form dominates in the fractured coal.The results of gas desorption experiments show that the initial gas desorption volume and velocity of the fractured coal are both greater than those of the intact coal.Using the Fick diffusion law,the study calculates the gas diffusion coefficients of the intact coal and fractured coal.The diffusion coefficients of the fractured coal are 2 times and 10 times greater than those of the intact coal at the time of 0-120 and 0-10 min,respectively.The objective of this work is to study the gas desorption characteristics of the high-rank intact coal and fractured coal.The gas adsorption,mercury porosimetry and gas desorption experiments were carried out in this study.Then,the theories of thermodynamics,diffusion mechanism and desorption kinetics were used to estimate the gas desorption characteristics.The results of gas adsorption experiments show that the initial isosteric adsorption heat of the intact coal is greater than that of the fractured coal,indicating that the gas molecules desorb more easily from fractured coal than intact coal.Using the mercury porosimetry,we find that the diffusion channels of fractured coal are more developed than those of intact coal.The difficult diffusion form dominates in the intact coal during the gas diffusing,while the easy diffusion form dominates in the fractured coal.The results of gas desorption experiments show that the initial gas desorption volume and velocity of the fractured coal are both greater than those of the intact coal.Using the Fick diffusion law,the study calculates the gas diffusion coefficients of the intact coal and fractured coal.The diffusion coefficients of the fractured coal are 2 times and 10 times greater than those of the intact coal at the time of 0-120 and 0-10 min,respectively.

关 键 词：Intact coal Fractured coal Isosteric adsorption heat Diffusion coefficient 

分 类 号：TD712[矿业工程—矿井通风与安全]