Instrument Air Dryer

Instrument Air Dryer is equipment for remove water vapor content on air (instrument air) from compressor. There are two methods to remove water vapor content on air by adiabatic and non adiabatic.


Adiabatic way could be read on this, and non adiabatic (heat transfer influence) will be describe detail as below.

Non adiabatic instrument air dryer usually use refrigeration cycle by R-404a as a refrigerant and at evaporator process, heat from instrument air compressor is absorb so water vapor when contact to air / refrigerant heat exchanger could be change from vapor to liquid as a dew point. Keep maintain a dew point temperature above 0 degree of Celsius or be save at above 4 degree of Celsius to avoid water vapor goes freeze at its heat exchanger.




Danger situation if air / refrigerant heat exchanger goes freeze because instrument air flow will get restriction and then instrument air pressure tank goes down. Setting expansion valve to maintain evaporator temperature not less than 0 degree of Celsius to avoid dew point temperature too low.