Ammonia Refrigeration advantages

Refrigeration is the process used to cool a fluid to a temperature below ambient.

There are three methods for refrigerating:

1)   Mechanical refrigeration

2)   Valve expansion

3)   Turbo expanders

Mechanical refrigeration includes two types; vapour compression (VCR) and vapour adsorption (VAR).

 Below videos describe process principles of these two type:

PRINCIPLES OF VCR

PRINCIPLES OF VAR

Ammonia refrigeration which is a type of VAR, is used extensively in food, petroleum, petrochemcial and chemical industry.

 Ammonia refrigeration system is in common with other VARs in advantages below over VCR systems:

•  Flexible operation and quick adjustment to varying loads
• Robust design with pumps as only rotating equipment and thus low maintenance
• Utilization of waste energy from the process

 The advantage of ammonia as a refrigerant in respect to other adsorbents are (like propane, propylene, …):

• Highly chemical stability
• Does not contribute to climate change
• Does not deplete ozone
• Leaks are easily detectable
• Needs less volume than the others so it means less piping and less components
• Is not soluble in oil, so no problem with lubrication oil of compressors.

 From the efficiency point of view also Ammonia (R-717) refrigeration system is 3% more efficient than R-22 and 10% more efficient than R-134a.

 Despite the above benefits we should consider that ammonia is:

• corrosive to copper alloys, so application of copper tubes and fittings is limited
• toxic, burnable and lighter than air, so personal protective equipment are required when working with ammonia.