Do you know what refrigeration equipment is?

    Refrigeration equipment is a device that combines a refrigerator and a facility that uses cold capacity. The design and construction of refrigeration equipment is to effectively use cold energy to refrigerate food or other items; to perform product performance tests and scientific research tests at low temperatures; to achieve certain cooling processes in industrial production, or to perform air conditioning. Items must release a certain amount of heat when they are cooled or frozen, and the enclosure structure of the refrigeration device will also transmit a certain amount of heat when in use. Therefore, in order to maintain the low temperature conditions in the refrigeration device, it is necessary to install a refrigerator to continuously remove the heat, or to use the melting of ice or the sublimation of dry ice to absorb the heat.

    Before the development of artificial refrigeration, humans had known to use natural ice and snow to maintain low temperature conditions in simple equipment, that is, to use natural cold sources. In China, natural ice was used to preserve food about 3000 years ago. There are verses about collecting, storing and freezing food with natural ice in the Book of Songs in the seventh century BC. Until modern times, people still use natural cold sources such as ice, snow and groundwater. The refrigeration equipment cooled with natural ice or artificial ice can only reach a limited low temperature, and the technical and sanitary conditions are poor, and it is difficult to meet various requirements. Modern refrigeration devices use refrigerators for cooling.
    In 1834, J. Perkins of the United States successfully trial-produced a man-powered refrigeration machine that uses ether as the working fluid and can work continuously. In 1844, J. Gory of the United States trial-produced a refrigerator using air as a working fluid, which was used to make ice and cool air in hospitals. From 1872 to 1874, D. Bell and C. von Linde invented ammonia compressors in the United States and Germany respectively, and made an ammonia vapor compression refrigerator, which is the beginning of modern compression refrigerators. In the 1850s, the Carré brothers in France successfully developed an absorption chiller and an ammonia absorption chiller using sulfuric acid and water as working fluids. In 1910, a steam jet refrigerator appeared. Freon refrigerant appeared in 1930, which promoted the rapid development of compression refrigerators. In 1945, the United States successfully developed a silver bromide absorption refrigerator.