Refrigerated Air Dryers
Although it does not offer as low a dew point as can be obtained with other types, the refrigerated dryer has been the most popular, as the dewpoint obtained is acceptable in general industrial plant air applications. The principle of operation is similar to a domestic refrigerator or home air conditioning system. The compressed air is cooled in an air-to-refrigerant heat exchanger to about 35 deg F, at which point the condensed moisture is drained. The air in then reheated in an air-to-air heat exchanger by means of the incoming air, which also is pre-cooled before entering the air-to-refrigerant heat exchanger. This means that the compressed air leaving the dryer has a pressure dewpoint of 35 deg F to 40 deg F. A lower dewpoint isn’t feasible in this type of dryer as the condensate would freeze at 32 deg F.
- Low initial capital cost
- Relatively low operating cost
- Low maintenance costs
- Not damaged by lubricant in the air stream
For some available models, this is not only a dryer, but an air treatment package that delivers an air quality of class 1.4.1 as per ISO 8573:2010 due to integrated filtration.