地热水系统采灌方案模拟优化研究——以苏北农村清洁能源供暖示范区为例  

A study of simulation and optimization of the productionreinjection scheme of a geothermal water system:A case study of the geothermal space heating demonstration area in northern Jiangsu countryside

作　　者：邹鹏飞 王彩会[2] 杜建国[2] 葛伟亚[3] 骆祖江[3] 孔刚[4] 邱杨 刘莉 ZOU Pengfei;WANG Caihui;DU Jianguo;GE Weiya;LUO Zujiang;KONG Gang;QIU Yang;LIU Li(School of Earth Sciences and Engineering,Nanjing University,Nanjing,Jiangsu 210023,China;Geological Survey of Jiangsu Province,Nanjing,Jiangsu 210018,China;School of Earth Sciences and Engineering,Hohai University,Nanjing,Jiangsu 211100,China;Natural Resources and Planning Bureau of Pei County,Xuzhou,Jiangsu 221600,China;Jiangsu East China Basic Geological Exploration Co.Ltd.,Nanjing,Jiangsu 210007,China)

机构地区：[1]南京大学地球科学与工程学院,江苏南京210023 [2]江苏省地质调查研究院,江苏南京210018 [3]河海大学地球科学与工程学院,江苏南京211100 [4]沛县自然资源和规划局,江苏徐州221600 [5]江苏华东基础地质勘查有限公司,江苏南京210007

出　　处：《水文地质工程地质》2023年第4期59-72,共14页Hydrogeology & Engineering Geology

基　　金：江苏省自然资源科技计划项目(2021033);江苏省自然资源发展专项资金(地矿类)项目(2020-1-8)。

摘　　要：在地热资源开发利用过程中,热储温度、压力会随开采量和时间的增加而降低,地热尾水的排放也会对环境造成热污染,热储回灌可以成为解决这些问题的有效措施。在进行地热开发利用之前,科学合理地规划采灌井的布局方式,探索避免采灌井过早发生热突破、实现地热资源高效利用的最优采灌方案,有利于延长地热井的使用寿命。江苏沛县安国镇所在的丰沛盆地为古近纪以来发育的新生代断陷盆地,岩溶裂隙型热储分布较为广泛,以奥陶系灰岩为主。文章在安国镇地热资源勘查成果的基础上,基于地热井抽水试验、回灌试验获取的采灌井间距、灌采比等重要参数,利用Feflow6.2软件建立了地下热水渗流与热量运移三维耦合数值模型,模拟预测了奥陶系灰岩热储层中地热水的可开采资源量,进行了采灌井开发利用方案的模拟优选。研究结果表明:RPX01开采井与RPX02回灌井合理井底间距为389 m;地热井的灌采比为1.29,确定了一抽一灌的方式进行可持续开发利用;水位降深稳定在50.61 m时,开采井可开采资源量为1000 m^(3)/d;开采量为1000 m^(3)/d、回灌量1000 m^(3)/d,回灌温度40℃时,10个供暖期后开采井水位下降45.49 m,温度降低1.44℃,是本次模拟方案中的最佳循环开发利用方案。上述结果为苏北农村清洁能源供暖示范区建设提供了科学决策依据。During the process of developing and utilizing geothermal resources,various challenges are encountered.One such challenge is the decrease in temperature and pressure of the geothermal reservoir as a result of the increasing geothermal exploitation and duration.In addition,the discharge of geothermal tail water poses a risk of thermal pollution,leading to environmental concerns.To address these issues effectively,reinjection of geothermal fluids into the reservoir can be implemented as a viable solution.Prior to initiating the geothermal development and utilization,it is crucial to conduct scientifical and rational planning of the layout of production and reinjection wells.This involves exploring optimal strategies for the production-reinjection scheme that prevents the premature thermal breakthrough and maximize the efficient utilization of geothermal resources,thereby extending the lifespan of the geothermal reservoir.The Fengpei Basin,a Cenozoic rift basin that developed since the Paleogene period,exhibits a widespread distribution of geothermal reservoirs,primarily composed of the Ordovician limestone with karst and fracture characteristics.Building upon the geothermal resource exploration results in the Anguo Town in Peixian County in Jiangsu Province,this study utilizes key parameters obtained from pumping tests and reinjection experiments,such as well spacing and the reinjection-to-production ratio.This paper establishes a 3D coupled numerical model of geothermal water seepage and heat transfer by using the Feflow6.2 software.The recoverable reserves of geothermal fluid within the geothermal reservoir are simulated and predictd,specifically the Ordovician limestone formation.Furthermore,a simulated optimization of the development and utilization scheme for the production-reinjection wells is conducted.The results reveal that an appropriate well spacing of 389 m between the producing well(RPX01)and the reinjection well(RPX02)is recommended.Moreover,the reinjection-to-production ratio,namely the ratio of aver

关 键 词：地热水系统 回灌 数值模拟 灌采比 优化方案 可持续开发利用 

分 类 号：P314[天文地球—固体地球物理学]