Study on a two-stage desiccant wheel dehumidification deep mine cooling system driven by mine water source heat pump

Deep mining is the primary direction for future mine development. However, deep mining causes heat damage, which seriously affects work efficiency and worker health. To satisfy the requirements of thermal comfort, a two-stage desiccant wheel dehumidification deep mine cooling system driven by mine water source heat pump (TSDW-DMCS-MWSHP) is proposed. The system consists of a two-stage desiccant wheel, water source heat pump, air cooler, and air heater. A water source heat pump is used to realize the dual supply of cold and heat, which provides cold and heat sources for cooling the mine airflow and heating the regeneration air. A two-stage desiccant wheel is used to achieve deep dehumidification. A heat and mass transfer model of the system is established and simulated. The effects of the main operating parameters on energy, dehumidification, and exergy performances are systematically investigated. The results show that when the inlet temperature of the mine airflow is 32 °C and the relative humidity is 80 %, the system can achieve a temperature difference of 6 °C, a humidity ratio difference of 11.7 g/kg, and an enthalpy difference of 36.1 kJ/kg. When the two-stage desiccant wheel operates at a low regeneration temperature of 60 °C, the TCOP , DCOP , and exergy efficiency reach their peak values of 2.8, 0.9, and 68.9 %, respectively. Compared with the ground centralized refrigeration system, the supply air relative humidity of the TSDW-DMCS-MWSHP is reduced by 13.3 %, and the COP is increased by 16 %. The TSDW-DMCS-MWSHP offers a viable solution for mitigating mine heat damage and advancing the sustainable development in the mining industry.