Sullair DHL-80 - Page 33

User Manual US-EN DHL Regenerative Dryer w/SHDC-2300 touch screen controller
1000-4544 R01
Subject to EAR. ECCN EAR99 and related export control restrictions.
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Stage 2:
● The left tower purge solenoid valve is closed and the left tower is re-pressurized to line
pressure. Once it is re-pressurized, the left tower is ready to start the drying process.
Stage 3:
● The left tower inlet valve is opened and it starts to dry the wet compressed air. The right
tower inlet valve is closed and the right tower purge valve is opened. This process
depressurizes the right tower. Now, as the dry air exits the left tower, a small portion of this
dry air (termed “Purge Air”) is redirected towards the right tower (flow controlled by the
repressurization valve). This compressed purge air expands to near atmospheric pressure
in the right tower, thereby increasing its moisture absorbing capacity. As this expanded dry
air flows through the right tower, it absorbs the H2O from the desiccant bed, exhausting it
through the exhaust muffler. At the end of this stage, the right tower desiccant bed will have
completely regenerated (i.e. completely free of moisture) and is ready for adsorbing
moisture from the incoming wet compressed air.
Stage 4:
● The right tower purge solenoid valve is closed and the right tower is re-pressurized to line
pressure. Once it is re-pressurized, the right tower is ready to start the drying process.
This process is termed as one cycle and it continues automatically without any need for user
intervention.
PLEASE NOTE: The left and right of the dryer is from the perspective of the operator standing in
front of the dryer (the controller side)
PLEASE NOTE: The desiccant material, if contaminated from lubricant oil, loses its absorption
property. Moreover during operation, the desiccant can release solid particles (powders)
particularly abrasive and extremely damaging for the final users.
● For this reason the dryer is equipped with two high efficiency filters:
- Inlet filter, 0.01 micron filtration grade, with differential gauge and electronic timer drain or
optional zero loss drain.
- Outlet filter, 1 micron filtration grade, with differential gauge and manual drain.