3. DESCRIPTION OF DEHUMIDIFIER CTR 500TT
a) Function
In a crawl space one is dependent on a dehumidifier with a constant flow of dry air so that
mould does not form.
This is achieved using a rotating dehumidifier, type Corroventa CTR
500TT. The regeneration process is continuous. The dehumidifier is not dependent on the air
temperature. The air can also be efficiently dehumidified far below freezing point. The fixed
desiccant that is used is silica gel and can be regenerated a nearly unlimited number of times.
Silica gel is a crystal that can absorb a lot of moisture, approx. 40% of its own weight. There are
different types to choose from for different areas of use. Inside the crystal there are lots of
small microscopic pores. This means that the surface area of the walls inside the crystal is very
large. One gram of silica gel has a moisture absorbent surface of 500 - 700 m
2
.
A CTR 500TT dehumidifier contains desiccant with a total drying aera of approx. 600,000 m
2
.
The dehumidifier is used to dry atmospheric air using the adsorption principle.
The adsorption rotor
The rotor has axially directed air ducts and consists of a highly active desiccant bonded in a
ceramic structure. The desiccant is not water soluble and therefore cannot be washed away or
blown out with exiting airflows.
The axially directed air ducts in the rotor give laminar flow with minimal pressure drop.
The dehumidification process
The desiccant is placed in a rotor (6). The air to be dried is sucked in through the inlet (3) by
means of a process air fan (10). The air passes a filter and then the drying rotor, after which the
dehumidified air goes through the dry air outlet (4) to the area to be kept dry. The rotor rotates
by means of a drive motor (7) and a drive belt (8). The moisture that is adsorbed in the rotor is
driven out by a small portion of the process air being heated by the heater (15) and then pass-
ing a smaller part of the rotor, which is thus regenerated. The wet air is removed via the outlet
(17) to the surroundings.
6
7
15
8
17
10
3
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