摘要
导水断层岩体的高渗透性为煤炭-水热型地热能高效协同开采提供了新思路,研究深部热-流-固耦合条件下断层岩体的渗透性演变规律是实现煤-热协同开采的重要前提。自主研制了热-流-固耦合三轴试验系统,开展了导水断层岩体热-流-固耦合特性试验。试验结果表明,热-流-固耦合作用下破碎岩体的渗透过程可以划分为冲蚀增透阶段及体缩抑流阶段,其中,冲蚀增透阶段发生在试验初期,岩体的渗透性参数(孔隙率、流速及渗透率)在该阶段迅速增长,进入体缩抑流阶段后保持小幅波动。高温下岩石颗粒的热膨胀效应抑制了岩体孔隙空间扩展,导致渗透参数在冲蚀增透阶段增长缓慢;水压越高,渗透参数在冲蚀增透阶段增幅越大,表明高水压的冲蚀效应更显著;加载轴压与围压均会促进岩体的体缩效应,抑制渗透压力的冲蚀效果,导致试样渗透特性降低。文章丰富了导水断层岩体热-流-固耦合特性研究,为煤-热高效协同开采提供了试验基础。
The high permeability of waterconducting fault rock mass provides a new idea for efficient coexploiting of coal and geothermal energy.The permeability evolution law of fault rock mass under deep thermalhydraulicmechanical(THM)coupling condition has become a prerequisite for the realization of coexploiting of coal and geothermal energy.The THM triaxial test system was independently developed and the permeability test of waterconducting fault fractured rock mass was carried out under the coupling effect of THM.The test results show that seepage process of rock mass under THM coupling can be divided into 2 stages:stage of erosion to increase permeability,stage of volume reduction to restrain flow.Among them,the stage of erosion to increase permeability occurred in the initial stage of the test,and the porosity,velocity and permeability of the fractured rock mass increased rapidly in this stage,and then kept small fluctuations in stage of volume reduction and to restrain flow.The thermal expansion effect caused by high temperature inhibits the expansion of pore space,as a result,the permeability parameters grow slowly in the Stage of erosion to increase permeability.The higher water pressure is,the greater the increase of permeability in the stage of erosion to increase permeability,indicating that the erosion effect of high water pressure is more significant.Both axial and confining pressure can cause the volume reduction effect of rock mass in fractured zone and inhibit the erosion effect of seepage,and lead to the decrease of permeability of the sample.This paper enriches the research on THM coupling characteristics of waterconducting fault rock mass,and provides laboratory test basis for efficient coexploiting of coal and geothermal energy.
作者
马丹
侯文涛
孔赛博
张吉雄
李樯
周楠
高富强
汪锋
刘勇
MA Dan;HOU Wentao;KONG Saibo;ZHANG Jixiong;LI Qiang;ZHOU Nan;GAO Fuqiang;WANG Feng;LIU Yong(School of Mines,MOE Key Laboratory of Deep Coal Resource Mining,China University of Mining and Technology,Xuzhou,Jiangsu 221116,China;Guangzhou Urban Planning Design&Survey Research Institute,Guangzhou,Guangdong 510060,China;College of Energy and Mining Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China)
出处
《采矿与安全工程学报》
EI
CSCD
北大核心
2024年第2期352-361,共10页
Journal of Mining & Safety Engineering
基金
国家自然科学基金项目(52122404,52130402)。
关键词
煤-热协同开采
断层岩体
热-流-固耦合特性
冲蚀效应
coexploiting of coal and geothermal energy
fault rock mass
thermalhydraulicmechanical coupling characteristics
effects of erosion
