康定花岗岩热物性参数与深部储层采热潜力评估  

Thermal properties of Kangding granite and evaluation of thermal extraction potential in deep reservoirs

作　　者：刘造保 吴名 LIU Zaobao;WU Ming(Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines,Northeastern University,Shenyang,Liaoning 110819,China;Institute of Deep Engineering and Intelligent Technology,Northeastern University,Shenyang,Liaoning 110819,China)

机构地区：[1]东北大学深部金属矿山安全开采教育部重点实验室,辽宁沈阳110819 [2]东北大学深部工程与智能技术研究院,辽宁沈阳110819

出　　处：《岩石力学与工程学报》2023年第8期1821-1831,共11页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(52278333);大学生创新创业计划项目(S2019101450029)。

摘　　要：准确测定高温高压下岩石热物性参数是一个困扰深部地热工程设计与采热潜力准确评估的难题。首先,测定康定花岗岩在不同高温及轴向应力加载下的导热系数和不同高温下岩石比热容与热膨胀系数演化特性。其次,基于测定的实验数据和离散裂缝网络方法,建立考虑热–水耦合的康定热储采热过程数值分析模型。最后,获得开采温度、压力和总发电量随康定热储开采时间的演化规律。研究表明,康定花岗岩的导热系数随温度升高而略微降低,而随应力升高而略升高;温度能提高岩石导热系数对应力的敏感性,且能提高热储岩石的储热能力和热变形行为。根据现有模型,康定深部热储的发电功率可达1.06 MW,总发电量可达3.11亿度。结果有助于康定深部地热工程的设计、建设与开发前景评估。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.

关 键 词：岩石力学 增强型地热系统 康定花岗岩 干热岩 热物性参数 地热热储 采热潜力 地热发电 

分 类 号：TU45[建筑科学—岩土工程]