带压环境下煤体瓦斯解吸特性及模型  

Gas desorption characteristics and model of coal under pressure environment

作　　者：梁跃辉 石必明[1,2] 岳基伟 钟珍 韩奇峻 张铖铖 彭杰 张海卿 梅文强 LIANG Yuehui;SHI Biming;YUE Jiwei;ZHONG Zhen;HAN Qijun;ZHANG Chengcheng;PENG Jie;ZHANG Haiqing;MEI Wenqiang(School of Safety Science and Engineering,Anhui University of Science&Technology,Huainan 232001,China;Scientific and Technological Research Platform for Disaster Prevention and Control of Deep Coal Mining,Anhui University of Science and Technology,Huainan 232001,China;Pingdingshan Tian′an Coal Industry Co.,Ltd.,Pingdingshan 467036,China)

机构地区：[1]安徽理工大学安全科学与工程学院,安徽淮南232001 [2]安徽理工大学煤矿深井开采灾害防治技术科技研发平台,安徽淮南232001 [3]平顶山天安煤业股份有限公司,河南平顶山467036

出　　处：《煤炭学报》2025年第3期1569-1582,共14页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(U23A20601,52304200);安徽省自然科学基金资助项目(2308085QE152)。

摘　　要：煤层瓦斯含量是矿井瓦斯防治的一个关键技术参数,在直接测定煤层瓦斯含量取样过程中,由于钻孔内风压的存在,煤样在钻孔内瓦斯解吸处于带压环境。然而,目前煤样在钻孔内的瓦斯损失量是基于常压环境下瓦斯解吸量进行推算的,其造成煤层瓦斯含量测定不准确。基于此,开发了一套带压环境下煤体瓦斯解吸实验平台,探究了煤样在正压和变压环境下瓦斯解吸量、解吸率、扩散系数的演化规律,构建了带压环境下煤体瓦斯解吸模型,采用有限元分析软件数值解算了扩散系数方程。研究结果表明:煤样在孔内运移阶段,其瓦斯解吸过程处于正压环境,解吸量、解吸率、扩散系数与解吸压力呈现负相关的关系;在孔口接样阶段,煤样由带压环境向常压环境突变,常压环境下瓦斯解吸量、解吸率、扩散系数与瓦斯压力呈现正相关的关系;带压环境煤体√t瓦斯解吸模型计算的损失量更接近于实验测试的瓦斯解吸量,然而传统法(法和幂函数法)推算的瓦斯损失量远远偏离实验测试的瓦斯解吸量;传统法需要测定常压环境下瓦斯解吸量,才能间接推算瓦斯损失量,而带压环境下煤体瓦斯解吸模型依据取样风压、瓦斯压力及取样时间,可直接获得煤样的瓦斯损失量;研究结果为瓦斯损失量的准确推算及煤层瓦斯灾害防治奠定理论基础。Coal bed methane content is a key technical parameter for mine gas prevention and control.In the process of direct determination of coal bed methane content sampling,due to the existence of wind pressure in the borehole,the gas desorption of coal samples in the borehole is in a pressure environment.However,at present,the gas loss of coal samples in boreholes is calculated based on the gas desorption amount under normal pressure environment,which results in inac-curate determination of coal bed methane content.In order to address the aforementioned key challenges,the research team developed a set of coal gas desorption experimental platform under pressure environment,explored the evolution law of gas desorption amount,desorption rate and diffusion coefficient of coal samples under positive pressure and variable pressure environment,constructed a coal gas desorption model under pressure environment,and used finite element ana-lysis software to numerically solve the diffusion coefficient equation.The results show that the gas desorption process of coal samples is in a positive pressure environment during the migration stage in the hole,and the desorption amount,de-sorption rate and diffusion coefficient are negatively correlated with the desorption pressure.In the orifice sampling stage,the coal sample changes from the pressure environment to the normal pressure environment,and the gas desorption amount,desorption rate,diffusion coefficient and gas pressure show a positive correlation in the normal pressure environ-ment.The loss calculated by the gas desorption model of coal under pressure is closer to the gas desorption amount of the√texperimental test.However,the gas loss calculated by the traditional method(method and power function method)is far from the gas desorption amount of the experimental test.The traditional method needs to measure the desorption amount to indirectly calculate the loss,and the pressure desorption model can directly obtain the loss according to the sampling wind pressure,gas pressure an

关 键 词：煤层瓦斯含量 带压环境 瓦斯解吸 损失量推算 矿井瓦斯防治 

分 类 号：TD712[矿业工程—矿井通风与安全]