多种测温方法在青海共和干热岩GR1井中的应用

Application of various temperature measurement methods in Well-GR1in Qinghai Gonghe hot dry rock

摘要:

干热岩钻孔温度是干热岩型地热资源评价的重要指标，目前大多数地勘工作的温度测量仪工作温度大都在180 ℃以下，然而随着干热岩钻孔深度和温度的增加，受钻孔内高温、高压的影响，出现超出仪器测温范围或测温数值不准确的情况。为此，本文利用青海共和干热岩GR1井采用BZM电子多点测温仪、MTCHT-H型测温仪以及多组温度计的方式进行了多种方法的单点测温，同时结合SKD-3000B井车测温、GRY-1型钻孔轨迹测量仪等多点连续测温方式进行对比分析。结果表明，单点测温结果更接近真实地层温度，但单点测温效率低，精度差；GRY-1型钻孔轨迹测温仪因隔热装置隔绝，温度传导效率较慢，测温结果偏低。需要进一步开发准确、有效、经济的高温井下温度测量仪器或方法。

Abstract:

Temperature is an important indicator for evaluation of hot dry rock geothermal resources. At present, most temperature measuring instruments for geological survey work only can work below 180℃. However, with the increase of the depth and temperature in hot dry rock drilling, downhole temperature may exceed the tool measurement range, or error may occur in temperature measurement due to high temperature and high pressure. During drilling of hot dry rock Well-GR1 in Qinghai Gonghe hot dry rock, single-point temperature measurement was performed with BZM electronic multi-point thermometer, MTCHT-H thermometer and multiple groups of thermometers in conjunction with multi-point continuous temperature measurement with the SKD-3000B logging truck and GRY-1 borehole inclinometer. Comparison of the measurement results show that single-point temperature measurement is closer to the real temperature, but it has low efficiency and poor accuracy; the GRY-1 tool gives lower temperature due to slow temperature transmission caused by heat insulation. It is necessary to develop accurate, effective and economical high-temperature measuring instruments or methods.