Efficiency Improvement and Application of the Groundwater Heat Pump Cooling System in Linglong Gold Mine

Deep thermal damage in mines has had a significant impact on mining efficiency and safety. Local cooling technology can effectively mitigate the problem of heat hazard prior to the formation of the return air system. Aiming at the problem of heat damage in the Lingbei transportation tunnel at the Linglong Gold Mine's -870 m level, a local cooling system based on water source heat pump is constructed. The basic parameters for the local cooling system are determined using measured data, calculation analysis, and numerical simulation. The refrigeration, water supply, heat discharge, and cooling systems are then optimized by utilizing underground water inflow, installing thermally insulated drainage pipelines, and adding an auxiliary pressure fan. Finally, a local cooling system based on groundwater heat pump is established. Once the system is stable, the overall temperature and humidity of the Lingbei transportation tunnel are significantly reduced; the working face temperature is reduced to 26.4 degrees C, the relative humidity is reduced to 61%, compared with that before cooling, the decline reached 11.9 degrees C and 37%, respectively, and the average temperature within 100 m of the working face is reduced to below 28 degrees C, which meets the requirements for safe production. The system addresses the critical issues of water supply, heat removal, and cooling in the local cooling system, lowers investment and operating costs, increases refrigeration efficiency, and serves as a reference for similar mines' deep mining processes.