基于叠加法的陕西省典型地貌单元岩土导热系数分析

近年来,浅层地热能受到广泛关注,但由于在开发利用过程中对地层导热性能分析不足,现有开发利用项目失败率较高。为解决这一问题,对陕西省不同地貌单元已开展的46组热响应试验结果进行整理,以线热源模型为基础,采用叠加法对陕西省典型地貌单元的导热系数进行了分析统计。结果表明: 山间盆地、沙漠高原和断陷盆地3种地貌单元的导热能力依次减小; 在同一地貌单元中,第四系黄土覆盖层越厚,钻孔的导热能力越差; 黄土塬地区导热系数大小差距较大,可进一步深入研究该地貌单元内导热系数的影响因素。通过对不同地貌单元岩土导热系数分布特征的研究,提出了各地区浅层地热能开发利用的相关建议,从而为进一步高效、高质开发浅层地热能提供思路和技术支持。

Analysis on thermal conductivity of typical geomorphological units in Shaanxi Province based on superposition method

In recent years, shallow geothermal energy has received extensive attention, but the failure rate of existing projects is high due to insufficient analysis of the thermal conductivity of the strata during the development and utilization process. In order to solve this problem, the authors collated 46 sets of thermal response test results that have been carried out in different geomorphological units in Shaanxi Province. Based on the linear heat source model, the thermal conductivity of typical geomorphological units in Shaanxi Province was analyzed by superposition method. The results show that the thermal conductivity of three geomorphological units(mountain basin, desert plateau and fault basin) decreases gradually. In the same geomorphological unit, the thicker the loess cover of Quaternary, the worse the thermal conductivity of the borehole. The difference of thermal conductivity in loess tableland is quite large, and the influencing factors of thermal conductivity in the geomorphological unit can be further studied. Based on the study of the distribution characteristics of thermal conductivity in different geomorphological units, some suggestions for the development and utilization of shallow geothermal energy in different regions were put forward, thus providing some ideas and technical supports for further efficient and high-quality development of shallow geothermal energy.