卸压速度对构造煤突出过程中瓦斯膨胀能的控制作用  

Control effect of pressure-unloaded speed on gas expansion energy released by tectonic coal during coal and gas outburst

作　　者：蒋静宇[1,2,3,4,5] 史孝宁 王成浩 程远平[1,2,3] 黄一鸣 JIANG Jingyu;SHI Xiaoning;WANG Chenghao;CHENG Yuanping;HUANG Yiming(State Key Laboratory of Coal Mine Disaster Prevention and Control,Xuzhou 221116,China;National Engineering Research Center for Coal Gas Control,Control,China University of Mining and Technology,Xuzhou 221116;Faculty of Safety Engineering,China University of Mining and Technology,Xuzhou 221116,China;Artificial Intelligence Research Institute,China University of Mining and Technology,Xuzhou 221116,China;Guizhou Research Institute,China University of Mining and Technology,Guiyang 550001,China)

机构地区：[1]中国矿业大学煤矿灾害防控全国重点实验室,江苏徐州221116 [2]中国矿业大学煤矿瓦斯治理国家工程研究中心,江苏徐州221116 [3]中国矿业大学安全工程学院,江苏徐州221116 [4]中国矿业大学人工智能研究院,江苏徐州221116 [5]中国矿业大学贵州研究院,贵州贵阳550001

出　　处：《煤炭学报》2024年第11期4473-4485,共13页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(52174217);江苏省高校“青蓝工程”优秀青年骨干教师资助项目(苏教师函[2019]31号)。

摘　　要：煤与瓦斯突出(简称“突出”)多发生在构造煤层。瓦斯膨胀能是参与突出的重要能量之一。构造煤体在突出连续发展阶段中将经历连续复杂的卸压过程,为了明确卸压速度在突出连续发展过程中对瓦斯膨胀能的控制作用机理,选取地质构造复杂、突出灾害治理难度较大的平煤十三矿突出煤层煤样为研究对象,开展了不同卸压速度条件下的构造煤型煤三轴加载试验、筛分试验和煤粒瓦斯解吸扩散动力学试验。基于试验结果揭示了不同卸压速度条件下构造煤体的粉化特征和瓦斯解吸规律,反算了不同卸压速度条件下破碎煤体的瓦斯解吸量和瓦斯膨胀能,提出了一种突出连续发展过程中的正反馈模型。结果表明:卸压对煤样强度和抵抗变形的能力具有一定的弱化作用,卸压速度越大,弱化作用越强,越容易发生破坏。随着卸压速度的提高,煤样破碎后的粉化程度增强,瓦斯解吸量亦随之增高,导致瓦斯膨胀能增大。卸压速度从0.01 MPa/s增大至0.1 MPa/s时,破碎煤样的瓦斯膨胀能增加了21.05%~40.00%。卸压速度的增大,使得构造煤样的破碎程度、气体流动通道和煤体内能增加,初始瓦斯解吸量也随之增加,最终导致瓦斯膨胀能的增加。研究表明卸压速度对诱导突出连续发展有着关键作用,其控制瓦斯膨胀能的正反馈过程不断循环是影响构造煤层突出连续发展的重要因素。The majority of coal and gas outbursts(referred to as outbursts for brevity)occurred in tectonic coal seams.Gas expansion energy stands out as a critical factor contributing to these outbursts.The development stages involve the rapid release of confining pressure within the coal.To elucidate the mechanism of how pressure-unloaded speed controls gas ex-pansion energy during the continuous development of outbursts,we conducted triaxial loading tests,sieving experiments,and gas desorption measurements on the outburst coal samples from the No.13 Mine of the Pingdingshan coalfield,a site with complex geological structures and significant challenges in managing outburst hazards,at different pressure-un-loaded speed.Based on the experimental results,we revealed the pulverization characteristics and gas desorption behavior of tectonic coal under different pressure-unloaded rates.Gas desorption volume and gas expansion energy of crushed coal at different pressure-unloaded speeds were back-calculated,proposing a positive feedback model for the continuous devel-opment of outbursts.The results indicate that unloading confining pressure weakens the strength and deformation resist-ance of coal,with this effect intensifying as pressure-unloaded speed increases.As pressure-unloaded speed increases,the degree of pulverization and gas desorption volume increase,resulting in a corresponding rise in gas expansion energy.When pressure-unloaded speed increases from 0.01 MPa/s to 0.1 MPa/s,gas expansion energy increases by 21.05%to 40%.As the unloading rate increases,the degree of fragmentation in the tectonic coal samples,the gas flow pathways,and the internal energy of the coal also increase.This leads to a higher initial gas desorption volume,ultimately increasing gas expansion energy.The positive feedback cycle involving pressure-unloaded speed emerges as a crucial factor influencing the continuous development of outbursts.It is shown that the positive feedback cycle process of pressure-unloaded speed controlling gas expansion ener

关 键 词：煤与瓦斯突出 卸压速度 粉化作用 瓦斯膨胀能 正反馈循环 

分 类 号：TD712[矿业工程—矿井通风与安全]