Introduce

The subsidiary product produced by coal chemical industry, liquid nitrogen, as a refrigerant, utilizes its physical characteristics of absorbing a large amount of heat from the outside during the gasification process, which releases a large amount of cold energy. An air bath type liquid nitrogen heat exchange device is used, and liquid ammonia exchanges heat with the ambient air through the pipes and extended fins of the heat exchange device. This is the process of phase change and temperature rise of liquid nitrogen in the device (gasification and overheating), which is the process of liquid nitrogen absorbing heat from the ambient air through the device, that is, the process of the device releasing cold energy to the ambient air. Every 1Nm of gasification ³ Liquid nitrogen, from which air can obtain approximately 327KJ of cold energy.
The air cooled liquid ammonia cooling device for mining is installed at the entrance of the mine air intake alley. By utilizing the ventilation capacity of the fan at the entrance of the air intake alley, cold energy is brought into the working face, thereby achieving the goal of cooling and eliminating heat damage to the mine working face.
20% of the nitrogen gas after heat exchange and gasification is directed to the goaf, and about 80% of the nitrogen gas after heat exchange and gasification is directed to the main return airway of the mine. After cooling with the ambient air inside the mine, the outlet temperature of the nitrogen gas is guaranteed to be above 0 ° C.