Ventilation refrigeration and cooling technology of high temperature heat damaged mine

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.