为了评价单井闭循环的热提取性能,优化注入参数,文章针对中国东北典型场地,基于井筒-储层耦合数值模拟和场地的运行监测数据,分析了地热系统短期(热响应测试)和长期(一个供暖季)的提热性能,并优化了系统运行注入温度和流量。结果显示,典型东北地区1500m长度的地热井在平均注入温度7益,注入流量7.7m3/h条件下,换热孔出口平均功率为65.2kW,一个供暖期出口与入口平均温差为4.9益,地层温度降低影响最大范围约7m,地层中的降温程度最大为23益,并可以在非供暖期得到较好的恢复。在不考虑运行成本和可持续开发的情况下,注入温度越低、流量越大,获得的换热功率也越大。在调整注入温度为5益和流量为6.3m3/h的情况下,可获得同样的换热功率,此时的运行成本最低,比现有方案成本降低20%。考虑运行成本和可持续开发的优化设计对单井闭循环地热供暖具有现实意义。

To evaluate the heat extraction performance and optimize the injection parameters of asingle-well Closed-Loop Geothermal System (CLGS), this paper analyzes the short-term (thermalresponse testing) and long-term (one heating season) heating performance of CLGS and optimizesoperation parameters including injection temperature and rate, based on wellbore -reservoircoupling simulation and site operation monitoring data for a typical site in Northeast China. Theresults indicate that the mean heat extraction rate is kW and the average temperaturedifference between the output and inlet isan injection flow rate of m/h for a vertical well of m. At the end of a heating season, themaximum range for temperature reduction in the formation is approximately m with the maximumtemperature decrease up toWithout considering operating costs and sustainable development, the low injection temperatureand large injection rate result in high heat extraction rate. Setting the injection temperature toand flow rate to m/h can minimize operating costs while meeting heating needs, reducing costsby% compared to the existing solution. The optimization design that considers operating costsand sustainable development has practical significance for a single well closed-loop geothermalsystem.