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Research on the Mobile Refrigeration System at a High Temperature Working Face of an Underground Mine

With an increase in mining depth, the problem of heat damage in metal mine working face has become increasingly prominent. In order to effectively reduce the temperature of the working face and provide a comfortable working environment for the miners, based on the concept of “cooling on demand”, a mobile refrigeration system for high-temperature working face was designed, and a field test was carried out in Dahongshan Copper Mine, Yunnan Province. At the same time, based on the experimental conditions, the parameter optimization research of the mobile refrigeration system was carried out. The results showed that: (1) The mobile refrigeration system could reduce the wet bulb temperature of the working face at the test site to below 30 °C, which is in line with the “Safety Regulations for Metal and Non-Metallic Mines” (GB16423-2020); (2) when the diameter of the air supply pipe was 600 mm and the air supply velocity was 12 m/s, the target cooling area could meet the continuous operation requirements stipulated in the “Safety Regulations for Metal and Non-metallic Mines” in China; (3) for every 2 °C decrease in supply air temperature, the average wet bulb temperature in the target cooling area decreased by 0.9 °C; (4) for every 10% decrease in supply air humidity, the wet bulb temperature and relative humidity in the target cooling area decreased by 0.76 °C and 4.38% on average, respectively. The research results provide new ideas and methods for the prevention and control of heat damage in metal mines.