Ammonia and CO2 A Perfect Marriage
Finding ways to cost effectively use ammonia and carbon dioxide together in cascade refrigeration systems would seem to be the perfect solution for a facility operator:
- Both fluids are 'natural refrigerants' and ultimately make industrial refrigeration safe for the environment.
- Ammonia/CO2 cascade refrigeration systems are at least as energy efficient as a traditional ammonia refrigeration system (Christensen 2006).
- Ammonia has high operating efficiencies even at high temperatures and so can efficiently reject heat even in high ambient environments. Using ammonia on the high side of a cascade system reduces the amount of ammonia in the system and allows it to be managed in ways that minimize or eliminate the negative effects of an ammonia leak on products or people. NH3/CO2 cascade systems are safer for workers in refrigerated facilities.
- Carbon dioxide is non-toxic and is highly efficient at low temperatures, which is the part of the refrigeration system that is closest to products and people. Using CO2 on the low side of a cascade system is safer for people and eliminates the risk of damage to products in the event of a leak.