Centrifual cold-water machine unit freon-12 substituted refrigeration agent

Abstract

The present invention relates to a refrigerating agent which can be substituted for freon-12 for centrifugal water chilling unit. The said refrigerating agent contains three components of HCFC-22, HFC-227 ea and HFC-124, to which HC-600 a also can be added so as to form four-component composite. Its preparation method adopts physical liquid-phase mixing process according to a certain proportion. Said invention can completely meet the requirements for environment protection, and its thermal property quite approaches to that of freon-12, so that the said invented refrigerating agent can be directly charged, it has no need of changing main component of a compressor and its system, and also has no need of changing production line.

Description

technical field [0001] The invention belongs to a refrigerant, in particular to a refrigerant used in a centrifugal chiller. Background technique [0002] Freon-12 (CFC-12) has been widely used in refrigeration systems and other fields for a long time because of its low toxicity, non-flammability, non-corrosion, and compatibility with other materials. However, since it was discovered in 1974 that CFC substances have a serious destructive effect on the atmospheric ozone layer, it has attracted increasing international attention, and it has been decided to gradually limit the production and use of CFCs. my country will stop using CFCs on January 1, 2010- 12. At present, as the refrigerant of centrifugal chillers, the use of CFC-12 still accounts for a considerable proportion. [0003] The parameters such as impeller speed and impeller basic size of CFC-12 centrifugal compressor are determined according to certain evaporation temperature, condensation temperature, thermophysic...

AI Technical Summary

Problems solved by technology

[0004] At present, in the prior art, HFC-134a is used as the main refrigerant to replace CFC-12. Its advantage is that it does not destroy the ozone layer, and its thermal performance is very similar to that of CFC-12. However, since the molar mass of HFC-134a is 102.03, and The molar mass of CFC-12 is 120.91, due to the difference between their molar masses, when directly filling, the blade tip speed must be increased by about 15% compared with CFC-12, so the impeller and transmission gear must be replaced, and the tubes of the heat exchanger Rearrangement is required, and the cost will increase greatly, otherwise the compressor will vibrate when it is running at full load and cannot work normally

In addition, some mixture substitutes for CFC-12 have been developed at home and abroad, such as R401 series, R406A, THR01 and THR02, etc. When these mixture substitutes replace CFC-12 in piston and screw compressor units, the operation effect All good, but when used in a centrifugal chiller, due to the difference in molar mass, if the size and size of the impeller are not changed, not only the cooling effect of the original CFC-12 cannot be achieved, but the chiller may not work properly

At present, there is no refrigerant substitute that can be directly used in CFC-12 centrifugal chillers at home and abroad without modification