CO₂ in industrial refrigeration

Solutions for CO₂ in industrial refrigeration

Industrial refrigeration is the first area where CO₂ has made a successful comeback. CO₂ in industrial refrigeration is used either as the low-stage refrigerant in cascade installations, or as a secondary coolant. Danfoss has more than 15 years of experience in developing components for sub-critical CO₂ systems and offers a complete range of valves for those applications, including:

• Control valves
• Line components
• Complete valve stations
• Filter-driers
• Sensors (temperature, pressure, level, gas detectors)

Danfoss has carried out all the required tests to ensure that components released for use with CO₂ are compatible in all respects. Danfoss industrial refrigeration specialists can help you with the selection of the right components for CO₂ applications. 

Why CO₂ in industrial refrigeration?

CO₂ belongs to the so-called “Natural” refrigerants, together with e.g. ammonia, hydrocarbons such as propane and butane, and water. While ammonia is a great all-round refrigerant for industrial refrigeration applications, its use is sometimes limited in areas where toxicity or flammability is a concern. In these and in a number of other applications, CO₂’s unique properties make it an attractive alternative: 

CO₂ is both non-toxic and non-flammable. In places where it is allowed to use only a limited amount of ammonia, cascade or secondary CO₂ systems are a great solution.

CO₂ cascade systems are very efficient for low temperature applications. E.g. for freezing fish. With CO₂ it is possible to freeze the fish faster and to lower temperatures, thus improving the quality and consuming less energy than in the same freezing process using other refrigerants.

CO₂ is excellent as a brine. The circulation rate required for efficient freezing with CO₂ is very low, thus reducing the size of the pumps, as well as the energy consumption. Heat transfer efficiency of CO₂ is nearly constant for all practical temperatures, which makes it very attractive as a brine for low and medium temperature applications

Technical developments since the 1920's have removed many of the barriers to the use of CO₂, which once existed. However, CO₂ users must still be highly aware of its unique properties and take the necessary precautions to avoid problems in their refrigeration systems. Danfoss specialists can help you to select suitable components, and the literature found on this website covers a great deal of Danfoss experience with CO₂ applications.