井下分层多参数监测系统的研制及其在地热回灌井的应用

Development of downhole stratified multi-parameter monitoring system and its application in geothermal reinjection wells

中文关键词: 地热  井下分层  多参数  监测系统  回灌井

英文关键词: geothermal  downhole stratification  multi-parameter  monitoring system  reinjection wells

中文摘要:

      以往的回灌试验、监测和研究仅针对整个热储层，并不能确定回灌流体的具体流向。砂岩热储含水段多 构成水平透镜状层或连续的水平层，之间有透水性差的黏土、泥岩层，阻止了垂向上地热流体的交换，导 致热储层间无明显的水力联系，注入的回灌流体在储层内以水平径流为主。本文从井下长置式测试仪、 井口固定升降装置、地面控制系统和远程通信系统 4个方面开展研究工作。成功研制井下分层多参数监 测系统，并引入到地热回灌井监测，实现了地热回灌井井下分层动态流速、压力及温度测量。该系统在 2 眼砂岩热储回灌井进行了野外试验测试，实现了砂岩储层回灌流体主渗流通道精确识别。本研究将为回 灌主渗流层位优选、采灌布局优化等研究提供基础数据和技术支撑。

英文摘要:

      Previous reinjection tests, monitoring and research only focused on the whole thermal reservoir, andcould not determine the specific flow direction of the reinjection fluid. The water-bearing section of the sandstone thermal reservoir mostly constitutes a horizontal lenticular layer or a continuous horizontal layer, and there are clayand mudstone layers with poor permeability between them, which prevents the exchange of geothermal fluids verti-cally. As a result, there is no obvious hydraulic connection between the thermal reservoirs, and the injected reinjec-tion fluid is mainly horizontal runoff in the reservoir. In this paper, the research was carried out from four aspects:underground long-term tester, wellhead fixed lifting device, ground control system and remote communication sys-tem. A multi-parameter monitoring system for downhole stratification had been successfully developed and intro-duced into the monitoring of geothermal reinjection wells, which realized the measurement of dynamic velocity, pres-sure and temperature of geothermal recharge wells. The system was tested in two sandstone thermal reservoir rein-jection wells, and the main seepage channel of reinjection fluid in sandstone reservoir could be accurately identi-fied. This research will provide basic data and technical support for the optimization of the main seepage layer of re-injection and the optimization of the layout of mining and reinject.