中国石油大学学报（自然科学版）2025，Vol.49Issue(6)：116-124,9.DOI:10.3969/j.issn.1673-5005.2025.06.011
枯竭页岩气藏地热开发潜力及不同闭式系统注水循环采热效率分析
Assessment of geothermal resources in depleted shale gas reservoirs and production efficiency of different closed-loop systems by water circulation
摘要
Abstract
Deep shale gas reservoirs in the Sichuan Basin possess abundant geothermal potentials.For instance,a total geo-thermal energy from three typical shale reservoirs has been estimated at 1.84×1013 GJ,with a recoverable portion of 9.22×1011 GJ,equivalent to 3.15×1010 t of standard coal.In this study,different closed-loop heat extraction models were devel-oped,including a single horizontal well(coaxial system)and a dual-horizontal well retrofitted into a complex structured sys-tem for extracting geothermal energy from depleted shale gas reservoirs,based on the Silurian Longmaxi Formation in the Jiaoshiba area.Finite-element simulations were performed to evaluate the well performance and examine the effects of well configuration and operational parameters.The simulation results indicate that,under conditions of a 1500 m3/d water circu-lation rate at 20℃injection temperature,and with 1500 m horizontal section and cement sheath thermal conductivity of 1.5 W/(m·K),the coaxial system initially can obtain a wellhead outlet temperature of 60.63℃and a heat extraction rate of 2948.91 kW,while that of the complex structured well can achieve 65.81℃and 3325.64 kW,respectively.After 10 years of operation,the wellhead temperature and heat extraction rate may decline to 40.00℃and 1451.40 kW for the coaxial sys-tem,and to 49.14℃and 2114.77 kW for the complex structured well,demonstrating the superior performance of the latter well configuration.Increasing the water circulation rate can enhance the heat output but lower the outlet temperature,and higher injection temperature can raise outlet temperature but reduce heat extraction rate.Longer horizontal section length can effectively improve the both production parameters.关键词
页岩气藏/废停井/地热能/闭式循环/采热潜力Key words
shale gas reservoirs/abandoned well/geothermal energy/closed loop circulation/heat mining potential分类
能源科技引用本文复制引用
王延永,赵亮洁,徐睿,王晓光,何勇明,董丽瑶..枯竭页岩气藏地热开发潜力及不同闭式系统注水循环采热效率分析[J].中国石油大学学报（自然科学版）,2025,49(6):116-124,9.基金项目
四川省科技计划项目(2021ZYCD004) （2021ZYCD004）
天府永兴实验室有组织科研项目(2023KJGG013,2023KJGG14) （2023KJGG013,2023KJGG14）
成都理工大学珠峰科学研究计划项目(80000-2024ZF11424) （80000-2024ZF11424）
