献县地热田碳酸盐岩热储示踪试验与模拟

Tracer test and simulation of thermal energy storage in carbonate rocks of the Xian County geothermal field

地热回灌过程中开采井热突破预测等理论模型方面的研究尚不完善。本文在献县地热田开展了对井回灌示踪试验,并运用Comsol Multiphysics建模软件进行了参数反演,应用该理论框架进行了示踪试验数据的定量解释及开采井热突破预测。结果表明,示踪剂回收率偏低,为0.0225%,采灌井存在1条优势通道,通道长度约为513.7m,总体表现为采灌井之间的水力联系较差。本文应用模型进行了参数反分析,计算得到拟合优度R2=0.7907>0.6,说明此优化结果与测量值有较强的相关性,拟合程度好。连续开采100a,不会发生热突破现象。

The theoretical model of predicting thermal breakthrough in production well during geothermal recharge is still not perfect.In this paper,we carried out well recharge tracer test in the Xian County geothermal field and performed parameter inversion using the Comsol Multiphysics modeling software.We used the software’s theoretical framework to explain the tracer test data quantitatively and predict thermal breakthrough in heat mining wells.The results demonstrated a relatively low tracer recovery rate of0.0225%,with one preferential passage of about 513.7 mlong in the geothermal doublet well,indicating poor hydraulic connection between the doublet wells.After parametric analysis,we calculated the goodnessof-fit R2 to be 0.7907,greater than 0.6,suggesting a strong correlation between the optimization result and measured value,therefore a good model fit.Our model predicts that 100 years of continuous exploitation will not cause thermal breakthrough.