摘要
地层与井筒之间的导热性能是以热传导为主的U型地热井技术取得成功应用的关键因素之一。针对U型地热井如何提升固井水泥的导热性能问题,采用室内实验和数值模拟方法研究了导热填料对固井水泥导热性能和取热效果的影响。研究结果表明,石墨相比于实验所用其他填料而言具有更好的提升固井水泥导热性能的潜力;随着石墨掺入比例的增加,固井水泥的导热系数近似线性增加,而抗压强度近似线性下降;高掺入比例的石墨固井水泥能显著提高工作介质在U型井水平段入口处的温度,但由于U型井换热主要发生在较长的水平段上,从长期运行来看过高的掺入比例并不能显著提高取热效果,建议固井材料中石墨掺入比例控制在10%左右。研究结果对U型地热井固井水泥导热填料类型筛选和掺入参数确定具有重要意义。
The thermal conductivity between the formation and the wellbore is one of the key factors for the successful application of U-shaped geothermal well technology based on heat conduction.Aiming at the problem of how to improve the thermal conductivity of cementing cement in U-shaped geothermal well,the influence of filler on the thermal conductivity of cementing cement and the heat extraction effect was studied by indoor experiment and numerical simulation methods.The results show that graphite has better potential to improve the thermal conductivity of cementing cement than other fillers.As the proportion of graphite added increases,the thermal conductivity of cementing cement increases approximately linearly,while the compressive strength decreases approximately linearly.A high proportion graphite cement can significantly improve the temperature of the working medium at the entrance of the horizontal section of the U-shaped well.However,since the heat exchange in the U-shaped well mainly occurs in the long horizontal section,from a long-term operation perspective,an excessively high blending ratio does not significantly improve the heating efficiency.It is recommended to control the graphite blending ratio in cementing materials at around 10%.The research results are of great significance for the selection of types of thermal conductive fillers for U-shaped geothermal well cementing cement and the determination of mixing parameters.
作者
齐治虎
姬玉平
王迪
徐影
李亚辉
刘文强
刘均荣
Qi Zhihu;Ji Yuping;Wang Di;Xu Ying;Li Yahui;Liu Wenqiang;Liu Junrong(Henan Yuzhong Geological Exploration Engineering Co.,Ltd.,Zhengzhou 450000,China;School of Petroleum Engineering,China University of Petroleum(East China),Qingdao 266580,China;Henan Institute of Geology,Zhengzhou 450000,China)
出处
《能源与环保》
2024年第2期70-76,共7页
CHINA ENERGY AND ENVIRONMENTAL PROTECTION
基金
国家自然科学基金面上项目(52174048)
河南省自然资源厅科技攻关项目(2021-1)。
关键词
U型地热井
固井水泥
导热性能
室内实验
数值模拟
取热效果
U-shaped geothermal well
cementing cement
thermal conductivity
indoor experiment
numerical simulation
heat extraction effect
