深部矿井岩层地热能协同开采治理热害数值模拟

Numerical simulation on heat hazard control by collaborative geothermal exploitation in deep mine

提出矿井岩层地热开采方法,并通过建立矿井岩层地热能协同开采多物理场耦合模型分析岩层地热开采的采热性能以及地热开采对井巷的降温效果。研究结果表明:尽管矿井长时间通风可以使巷道内温度降低,但降温缓慢,降温幅度有限;采矿层下方的岩层注水采热后,巷道围岩温度快速降低,巷道内风流温度显著下降;冷质注入岩层降低巷道进风端温度后,巷道后端温度也明显降低;在采热初期,热生产通道靠近注入井侧的采热量最大,但随着生产时间延长,其采热温度均逐渐下降;经计算,单个采热通道10 a内共可获得1.68×1015 J的热量。

The method for collaborative geothermal exploitation was proposed,and a fully coupled model was developed to analyze the geothermal exploitation process and performance of heat hazard control.The results show that a large amount of ventilation in the mine can reduce the temperature in the roadway,but the temperature decreases slowly and slightly.The temperature of surrounding rock and airflow in the roadway decreases rapidly and obviously after the heat production by continuous injection and production in the strata below the mining layer.When the temperature at the head of the tunnel is decreased by the cold mass injection rock,the temperature at the back of the tunnel is also significantly reduced.In the early stage of heat recovery,the heat production channel near the injection well side has the largest thermal extraction efficiency.With the increase of the heat recovery time,the heat production temperature of production fluid of the system reduces.The heat recovery of one heat production channel is 1.68×1015 J within 10 years.