CO2
CO2 as a cascade refrigerant
In installation where CO2 is used as refrigerant, it is either used in subcritical conditions, below 30°C, in cascade with another refrigerant, or in transcritical conditions, above 30°C, as single refrigerant.Cascade refrigeration systems and their advantages
The use of CO2 with a second refrigerant is particularly suited to applications where goods must be cooled or stored at temperatures below -30°C. This concept is also perfect for conversions of low temperature R22 installations. CO2 can be used to cool goods or industrial premises to below -50°C.Optimum energy efficiency : Combining two compression cycles in a cascade system means that it is possible to operate each compressor at a reasonable compression ratio and optimise energy efficiency.
Health and safety guaranteed : CO2 is non-toxic, non-inflammable and suitable for use with food: contact with CO2 does not render foodstuffs unfit for consumption.
Reduced installation costs : Thanks to its particular thermophysical and thermodynamic properties, the CO2 flow rate is lower and the compressor needed is smaller than for a system using an HFC refrigerant.
Safety and environmental protection : HFC refrigerant is only required in the high stage of the cascade.
Diverse applications : AXIMA REFRIGERATION has already installed numerous systems using this technology for frozen goods storage, freeze-drying coffee, the seafood processing industry …
The use of CO2 in cascade systems for sub-zero temperatures is now becoming the standard in the food industry, supermarkets and logistics.
