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In order to alleviate the problem of mine thermal damage, this paper proposes to put cold water pipe into the surrounding rock of roadway, and reduce the temperature of surrounding rock by intercepting the high temperature through the cold water pipe. According to the similarity principle, a cold water interception and cooling experimental system for high temperature surrounding rock was built. Experiments were conducted by changing cold water velocity, inlet time and surrounding rock temperature, etc. Combined with COMSOL simulation, the influence of different diameters and spacing layouts of cold water pipe on cold water interception and cooling effect of roadway surrounding rock was analyzed. The results show that when other conditions remain unchanged, the cooling range of surrounding rock increases with the increase of cold water velocity, inlet time and temperature difference between surrounding rock and cold water. When the diameter of the cold water pipe is 10 cm and the vertical distance is 2.5 m, the average temperature of the roadway wall after cooling is 23.4 ℃.

In this paper, the deep hole and shallow hole temperature measurement technology is used to measure the rock temperature in No.13 mining area of Yangchangwan Coal Mine, and the cooling circle range of 937 m elevation roadway for the return air downhill in No.13 mining area and 430 m elevation roadway for the auxiliary transportation downhill in No.13 mining area are determined. The COMSOL software is used to analyze the surrounding rock temperature distribution, and the reliability of the surface borehole temperature measurement data is verified according to the temperature measurement results. Combined with the ground borehole temperature measurement data and the deep hole and shallow hole temperature measurement results, the ground temperature gradient and the heat damage area are defined, which provides a basis for the subsequent heat damage treatment.

Taking Xinjulong Mine in Juye Mining Area as the object, the ventilation difficulties and cooling difficulties were analyzed, and a graded cooling method combining the full air volume cooling at the wellhead and the underground centralized cooling was proposed. The air flow temperature was studied to study its cooling effect. The ventilation route of the mine is extended, the cross section and direction of the tunnel and the bifurcation or convergence point increase, the resistance and local resistance of the wind flow increase, and the heat production of air compression increases. The heat exchange between wind flow and surrounding rock is strengthened, which aggravates the heat damage of high-temperature mines. The full air volume cooling system at the wellhead is used to reduce the air flow temperature at the air inlet of the mine, leaving the high temperature air flow heat on the ground. The underground centralized cooling system is used to solve the air flow cooling of the underground working face. After cooling, the temperature of the air flow at the entrance of the wellbore is kept below 19 ℃. After the air flow enters the bottom of the well, the temperature along the ventilation route is relatively stable, and the overall variation range is within 2 ℃. After adopting the underground centralized cooling system, the temperature difference between the inlet and return air of the working face is 4 ℃. The combination of wellhead cooling and downhole cooling can effectively improve the underground environment.

Aiming at the thermal hazards of mining face in Mengcun Coal Mine, a movable air chilled refrigeration system for coal mining face is studied based on the mine water supply and drainage system to reject heat. According to the present situation of thermal hazards in Mengcun Coal Mine, the chilling requirement of coal mining face is calculated. The applicability of two local refrigeration systems, water cooling and air cooling, in coal mining face is analyzed. The characteristics of water gushing from coal seam roof and low water temperature are analyzed. The technology of moving air-chilled refrigeration system in coal mining face is proposed, where the cooling water of refrigeration unit is taken from mine water supply pipeline and discharged to tunnel water ditch. A ZLF-450 movable air-chilled refrigeration unit was selected to test in the first mining face. The results show that: the return water temperature of the cooling water from the refrigerator is slightly higher than that of the mine water, and the water temperature rising after mixing with the water from the mining face in the ditch is only 0.4 ℃; the refrigeration unit operates normally, energy efficiency ratio reaches 3.05 and average temperature of the working face reduces by 2.8 ℃; the system uses mine water supply and drainage system to reject heat without laying any special pipeline for refrigeration system, which greatly reduces the cost of the refrigeration system.