fisair DFRA Series, User Manual

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User Manual DFRA Series |
15
4. Operating principle.
The FISAIR DFRA series air dehumidifiers operate using a substance (silica gel) which
adsorbs moisture from the air and is configured as a cylinder with many small channels
of this material all running in the same direction as the air flow.
The front surface of the base of this cylinder is divided into two zones: one is intended to
carry out the drying process, and the other to regenerate or reactivate the desiccant. The
large surface contact area of air to desiccant material within this configuration enables
an effective drying process to be achieved with a minimum volume of material.
The dry/process air circuit occupies 75% (270°) of the surface area of the desiccant rotor
in the FISAIR DFRA series dehumidifiers, where the material adsorbs water vapour from
the air passing through it. The reactivation air circuit is heated by a heating component
and passes through the rotor in the opposite direction to the process air. This removes
moisture from the desiccant material; thus regenerating it for a new cycle.
A rotor motor (low power gearmotor with a V-belt drive on the perimeter) ensures the
drying process is continuous and uniform.
The system design is completed with a set of seals separating the two air circuits and
seals around the perimeter of the rotor; thus ensuring separation between air flows.
Figure 1: Operating principle of drying by adsorption rotor.
Calentador de
reactivación
Aire
seco
Aire de
reactivación
Sector de
reactivación
Aire
mojado
Rotor
desecante
Aire de
proceso
Reactivation
sector
Reactivation
heater
Reactivation air
Dry air
Moist air
Process air
Desiccant rotor