Air conditioning refrigerant specific classification and price

Air conditioning refrigerant specific classification and price

In the refrigeration device, there must be a working fluid in which the state changes and completes the thermodynamic cycle process. Only the refrigeration device can provide continuous and stable cooling to the outside world, and the circulating working fluid is called refrigerant.

　　 Refrigerant is an indispensable thing in the refrigeration system. Its importance is equivalent to blood in the human body. Without blood in the refrigeration system, the refrigeration system cannot work.

　　 pointed out in the reverse Carnot cycle that the size of the coefficient of refrigeration has nothing to do with the nature of the refrigerant, but in the theoretical and actual refrigeration cycle, the physical characteristics of the refrigerant have an important influence on the quality of the refrigeration cycle. In addition, when selecting refrigerants, it is also necessary to consider various factors such as the chemical stability, toxicity, flammability, price, and impact on the ecological environment of the refrigerant.

　　With the development of science and technology, the refrigerant used in refrigeration devices has been screened. The main purpose is that the refrigeration device can have safe, reliable and good economic operation performance within the specified refrigeration temperature and will not cause environmental pollution.

　　 Type of refrigerant

At present, there are dozens of types of substances that can be used for refrigeration, but in the ordinary refrigeration range (-120~+5℃), there are only a dozen refrigerants used, while only a few refrigerants are used in air conditioning refrigeration systems. Kind.

　　1, Freon

　　 Freon is a halogen derivative of saturated hydrogen hydrocarbon. According to the different atomic numbers of Freon chemical substances, there can be many types of Freon, and many codes can be compiled according to the prescribed numbering method. For example, the code name of Freon 22 is R22, and the code name of Freon 134a is R134a.

Freon is an organic compound formed with the development of the organic chemical industry in the 1930s. It should be admitted that the emergence of many kinds of Freon has greatly improved the compressor refrigeration technology.

　　2, inorganic compounds

　　Water and ammonia are the first two refrigerants using inorganic compounds. At present, ammonia is mainly used in large and medium-sized refrigerators and ice-making systems, while water is only used in lithium bromide absorption refrigeration devices. The code name for ammonia as a refrigerant is R717, and water is R718.

　　3, mixed refrigerant

　　 Mixed refrigerant is a mixture of two or more refrigerants mixed in a certain proportion. It can obtain better cycle performance than a single compound when it is produced at a certain interval of low temperature.

　　 Mixed refrigerants are divided into two types: azeotropic mixed refrigerants and non-azeotropic mixed refrigerants.

　　Non-azeotropic mixed refrigerant: The refrigerant has an azeotropic point under a certain pressure. The temperature of the liquefaction or gasification process does not change under a certain pressure. Commonly used azeotropic mixed refrigerants are R502, R500 and so on.

　　Non-azeotropic mixed refrigerant. This refrigerant has no azeotropic point under a certain pressure, and the temperature will change accordingly during the liquefaction or gasification process. Therefore, in the circulating refrigeration of the variable temperature heat source, the use of a non-azeotropic mixture can reduce the heat transfer temperature difference between the evaporator and the condenser, and improve the operating performance of the refrigeration device. Non-public boiling mixed refrigerants mainly include R12/R13, R22/R114, etc.