黄陵矿区地热特征与煤热共采前景分析

Analysis of geothermal characteristics and coal-thermal co-exploitation prospect in Huangling mining area

为研究黄陵矿区地热地质特征及地热资源开发利用,整理和研究了黄陵矿区85个煤孔测井井温资料,梳理测温孔在48~72 h的近似稳态测温数据,编制了有代表性测温孔孔底温度曲线,同时计算了矿区地温梯度,绘制了黄陵矿区地温梯度特征分布图,并在此基础上绘制了500、1000、1500 m垂深地温分布特征图。同时,结合采集的岩石热导率测试数据,计算出黄陵矿区的大地热流值,并对地热资源进行了评估。研究结果表明,黄陵矿区测温钻孔井底温度恢复与井内稳定时间之间呈指数函数关系,以此建立了温测钻孔井底温度变化的校正公式;黄陵矿区主要地热参数为地温梯度在1.1~5.2℃/hm之间,平均值为2.7℃/hm;500 m垂深平均地温为24.99℃,1000 m垂深为38.53℃,1500 m垂深为52.07℃;岩石热导率为2.0~4.0 W/(m·K),在3.0~3.5 W/(m·K)时最多,平均值为2.54 W/(m·K);大地热流值为32.71~97.62 mW/m^(2),平均值为63.17 mW/m^(2);在平面上,地温梯度、地温场、大地热流总体呈现为南高北低、东高西低的分布趋势。基于黄陵矿区地热资源评估,矿区的热储层地热资源量为3.11×10^(19)J,可采热能储量为4.65×10^(18)J。目前黄陵矿区煤热共采地热利用多集中在矿井余热,考虑到黄陵矿区优异的地热赋存及矿井开采条件,进一步开展煤-热共采地热利用技术的研究及工程示范具有重要的示范意义。

In order to study the geothermal geological characteristics and the exploitation and utilization of geothermal resources in Huangling mining area,the logging well temperature data of 85 coal boreholes in Huangling mining area were analyzed and studied,and the approximate steady temperature measurement data of temperature measuring holes in 48 to 72 hours were sorted out,and on this basis,the distribution characteristics of vertical ground temperature at depths of 500,1000,and 1500 meters were plotted.At the same time,combined with the collected rock thermal conductivity test data,the earth heat flow value in Huangling mining area was calculated,and the present earth heat flow distribution map of the mining area was drawn,and the geothermal resources were evaluated.The results showed that there was an exponential function relationship between bottom hole temperature recovery and borehole stability time in Huangling mining area,and the correction formula of bottom hole temperature change was established.The main geothermal parameters of Huangling mining area were as follow:the geothermal gradient was between 1.1 and 5.2℃/hm,and the average value was 2.7℃/hm;the average earth temperature at 500 m vertical-depth was 24.99℃,while 38.53℃at the vertical depth of 1000 m,and 52.07℃at the vertical depth of 1500 m;the thermal conductivity of rock was from^(2).0 to 4.0 W/(m·K),with most ranging from^(3).0 to 3.5 W/(m·K)and an average of 2.54 W/(m·K);the earth heat flow value was 32.71 to 97.62 mW/m^(2),with an average value of 63.17 mW/m^(2);the geothermal gradient,geothermal field and earth heat flow were generally high in the south and low in the north,and high in the east and low in the west on the plane.Based on the geothermal resources evaluation of Huangling mining area,the geothermal resource quantity in the thermal reservoir of the mining area was 3.11×10^(19)J,and the recoverable thermal energy reserve was 4.65×10^(18)J.At present,the geothermal utilization of coal-thermal co-exploitation in Huangling mining area is mainly concentrated in the waste heat of mines.Considering the excellent geothermal occurrence and mining conditions in Huangling mining area,further research and engineering demonstration of coal-thermal co-exploitation geothermal utilization technology have important demonstration significance.