Thermal properties of Kangding granite and evaluation of thermal extraction potential in deep reservoirs
LIU Zaobao1，2，WU Ming1，2
(1. Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines，Northeastern University，Shenyang，Liaoning 110819，China；2. Institute of Deep Engineering and Intelligent Technology，Northeastern University，
Shenyang，Liaoning 110819，China)
Abstract：Accurately measuring the thermophysical parameters of rocks under high temperature and high pressure is a challenging problem for the design of deep geothermal engineering and the accurate evaluation of heat recovery potential. Firstly，the thermal conductivity of Kangding granite was measured under different high temperatures and axial stress loadings，and its evolution characteristics of specific heat capacity and thermal expansion coefficient were measured under different high temperatures. Secondly，a numerical analysis model was established for the thermal storage and production process of Kangding reservoir considering thermal-hydraulic coupling based on the measured experimental data and the discrete fracture network method. Finally，the evolution law of mining temperature，pressure，and total power generation with the thermal extraction time of Kangding thermal reservoir was obtained. The results show that the thermal conductivity of Kangding granite decreases slightly with the increase of the temperature and increases slightly with the increase of the stress. Temperature can increase the sensitivity of the thermal conductivity to the stress，and can increase the thermal storage capacity and the thermal deformation of geothermal reservoir rock. According to the established model，the generated power of Kangding deep geothermal reservoir can reach 1.06 MW，and the total power generation can reach 311 million kW•h. The results are helpful to the design，construction and development prospect evaluation of Kangding deep geothermal project.
刘造保1，2，吴 名1，2. 康定花岗岩热物性参数与深部储层采热潜力评估[J]. 岩石力学与工程学报, 2023, 42(8): 1821-1831.
LIU Zaobao1，2，WU Ming1，2. Thermal properties of Kangding granite and evaluation of thermal extraction potential in deep reservoirs. , 2023, 42(8): 1821-1831.
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2023, Vol. 42 
