The Need For An Air Dryer
whether you can afford It or not, effective managements would continously monitor costs. Wet compressed air undermines efficiency from the smallest to the largest system. It is a fact that moisture in compressed air is must. Further, where oil is used as lubricant in the compressor, the oil combines with moisture to from an emulsion which rapidly degrades the control system perfromance by corroding the jets and orifices of pneumatic instuments. Effective filteration and drying is therefore a must.
Cause of Moisture
A simple illustration, explains the amount of moisture present in compressed air.
You will note that the compressor suction side condition are 32 Celcius and 50% RH at 1 Atm. Abs which is an average Indian condition. After compression at 8 Atm. Abs, the valume of air reduces by 8 times I.e 400% & air temperature is very high, this air is passed through a water cooled after cooler and its temperature. At this temp, the air connot hold more than 100% RH moisture. The excess 300% of the vapour is condensed to liquid moisture which remains suspended in the air and con be separated by filters upto an efficency of 99% only. The air after filteration is 100% wet(saturated) air. This saturated air will condense its water vapour at the first available opprotunity i.e. whereever cooling due to expansion takes place