Flow diagram
Reference
Designation
Reference
Designation
AIR INLET
Air inlet
V4
Regeneration valve
AIR OUTLET
Air outlet
V5
Left check valve
A
Left desiccant tower
V6
Right check valve
B
Right desiccant tower
M1
Blow off silencer
V1
Left 3–2 valve
M2
Regeneration silencer
V2
Right 3–2 valve
N1
Nozzle
V3
Blow off valve
Depending on the dryer size, the dryer can be composed of a single dryer module (flow diagram:
see above), or a combination of a number of dryer modules in parallel.
Operation principle
The operation cycle of the dryer is repetitive and is controlled by a factory set timer in the
controller or by the PDP sensor (pressure dew point sensor), which is optionally available. While
the desiccant in one tower dries the compressed air, the desiccant in the second tower is being
regenerated. Regeneration of the desiccant is achieved by means of purge air from the drying
tower.
The compressed air entering the dryer is led to one of the towers by means of one of the two 3–2
valves. The position of the 3–2 valves is controlled by the solenoid valves. As the air flows
upwards through the tower, the desiccant adsorbs the water vapor and the compressed air is
dried. The dried air leaves the dryer via the outlet check valve.
A small portion of the dried air passes a nozzle, expands to atmospheric pressure and flows
downwards through the other tower, regenerating (drying) the desiccant. A nozzle for operation of
the dryer at 7 bar is installed as standard. Alternative nozzles for use at other operating
pressures are available. Contact your supplier. The regeneration air is released via the
corresponding solenoid valve and the silencer. The solenoid valves are controlled by the timer.
Instruction book
12
2920 7111 40