Pros and cons of using eco-friendly refrigerants in refrigeration plants
Alternative refrigerants are safe to the ozone layer and climate. At the same time, each of them is more or less acceptable for certain areas due to their properties. Here are the major properties of alternative refrigerants. “+” stands for “Yeas” and “-” for “No”. So, if you see “+” in Toxicity column, then the refrigerant is non-toxic.
Refrigerant | Availability* | Toxicity | Flammability | Can be used for retrofit | Specific features of plants |
Propane (R290) | + | — | + | + | Limited charge, fire safety measures to be taken |
Isobutane (R600a) | + | — | + | —** | Limited charge, fire safety measures to be taken |
Ammonia (R717) | + | + | + | —** | Plant components cannot contain copper, zinc, cadmium, mercury and rubber. Fire and toxicity safety measures to be taken. |
Carbon dioxide (R744) | + | — | — | — | Plant components should withstand high working pressures |
HFO | — | — | + | + | Fire safety measures to be taken |
Water | + | — | — | — | Limited use: temperatures over 0 °C are controlled and maintained. Plant components should be made of corrosion-resistant materials |
Air | + | — | — | — | Fundamentally different design (as compared to vapor compression refrigeration plants). Limited use: air-conditioners of airplanes, extra low-temperature plants. |
** — retrofit is possible in theory, but requires deep conversion and/or leads to loss of performance, so in practice the refrigerant is used in a specially designed plants.