高温作用对三维应力下花岗岩渗透率影响试验研究  

Experimental study on the effect of high temperature on the permeability of granite under three dimensional stress

作　　者：唐巨鹏[1,2] 魏志豪 邱于曼 TANG Jupeng;WEI Zhihao;QIU Yuman(School of Mechanics and Engineering,Liaoning Technical University,Fuxin 123000,China;New Energy Research Center,Liaoning Technical University,Fuxin 123000,China)

机构地区：[1]辽宁工程技术大学力学与工程学院,辽宁阜新123000 [2]辽宁工程技术大学新能源研究中心,辽宁阜新123000

出　　处：《辽宁工程技术大学学报（自然科学版）》2023年第5期513-520,共8页Journal of Liaoning Technical University (Natural Science)

基　　金：国家自然科学基金项目(51874165);辽宁“兴辽英才计划”支持项目(XLYC1902106)。

摘　　要：为揭示三维应力对高温后花岗岩热储层渗透率影响的规律,以松辽盆地地热开采为工程背景,以高温(150℃~650℃)处理后花岗岩为试验对象,利用自主研发的渗透率测量装置,以CO_(2)为渗透介质,进行了三维应力下(不同孔隙压、轴压及围压)花岗岩气体渗透率试验,得到了不同三维应力组合下花岗岩渗透率;分析了温度、孔隙压、体积应力对花岗岩渗透率的影响规律。研究结果表明:花岗岩渗透率随处理温度升高呈指数增加趋势,550℃以下时渗透率增长缓慢,550℃~650℃渗透率急速上升;孔隙压较小时,易发生气体滑脱效应,花岗岩渗透率随孔隙压增大而减小,到达某一临界值时,渗透率随孔隙压增大而增大,临界值与温度和体积应力有关;随着体积应力增大,花岗岩被压密,有裂隙闭合,连通性减弱,花岗岩渗透率减小。In order to reveal the influence law of three-dimensional stress on the permeability of granite thermal reservoir after high temperature,this study took the geothermal exploitation of Songliao basin as the engineering background,the high temperature(150℃~650℃)after processing granite as test object,and used the independent research and development of permeability measuring device.With CO2 as permeable medium,under the three-dimensional stress(different pore pressure,axial pressure and confining pressure)granite gas permeability test was carried out,and the granite permeability under different combination of three-dimensional stress was obtained.The influences of heating temperature,pore pressure and volumetric stress on granite permeability were analyzed.The results show that the permeability of granite increases exponentially with temperature,and the permeability increases slowly within 550℃,while the permeability increases rapidly between 550℃and 650℃.It is found that the gas slippage effect is easy to occur when the pore pressure is small,and the permeability of granite decreases with the increase of pore pressure.When the pore pressure increases to a certain critical value,the permeability of granite increases with the increase of pore pressure,and the critical value is related to temperature and volume stress.With the increase of bulk stress,the granite is compressed,the original fractures are closed,the connectivity is weakened,and the permeability of granite decreases.

关 键 词：增强型地热系统 花岗岩 渗透率 高温作用 三维应力 体积应力 

分 类 号：TK529[动力工程及工程热物理—热能工程]