煤矿矿井回风是煤矿生产中的主要低温热源,寒冷地区的矿井回风温度多在20℃左右,相对湿度90%左右。此外,矿井回风受井下围岩及煤壁换热影响为主,热参数受季节性影响较小,最冷月与最热月的矿井回风的平均温度差大约3℃左右,湿度基本不变,因此矿井 Coal mine return air is the main low-temperature heat source in coal mine production. The temperature of return air in mine in cold area is mostly around 20 ℃ and the relative humidity is about 90%. In addition, the mine return air is affected by underground wall rock and coal wall heat transfer, and the seasonal variation of thermal parameters is small. The average temperature difference between the return air from the coldest month and the hottest month is about 3 ℃, and the humidity is basically not Change, so mine