Desiccant rotor : DESSICA silica gel rotors

In most of the world, atmospheric humidity throws up challenges of different kinds to homeowners and businesses. In the manufacturing sector, companies that work with foodstuffs, pharmaceuticals, chemicals, batteries, electronic components and more need to try to find solutions to levels of relative humidity on their premises that can cause disruption at different stages of the production process. The desiccant rotor, or to be more specific, desiccant silica gel rotors, are such a technical solution. The Dessica Silica Gel rotors are designed to be used in most environments for dehumidification applications with high performance and long life.

Improving ventilation is one obvious way of drying out a premises. However, the effectiveness of this approach depends largely on weather conditions outside Indeed, improving an outside airflow in the premises can for example:

• In winter: decrease the relative humidity by blowing more dryer air but it will also add a calorific power consumption because the air is most likely colder than the premises atmosphere.
• In summer: The atmosphere in the premises should be colder than the outside so upgrading the outside airflow will increase relative humidity (since hotter air can contain more absolute humidity) and add the need to cool down the atmosphere which mean adding frigorific consumption.

Those two scenario are few among many other case which will worsen the premises humidity and adding temperature control issues – not something we have much control over!
Alternatively, we can heat premises to lower relative humidity. However, this has no impact on absolute humidity and the dew point. As explain previously the more the air is hot the more water it can contain. So by rising the temperature the relative humidity will decrease but the absolute humidity will remain the same. Increasing the temperature imply increasing power consumption which is also expensive.

However, there are alternatives to desiccant rotor dehumidifiers, so it’s worth taking a look at precisely why these are not generally as effective. Indeed, Dessica Silica Gel rotors are also suitable for use in Desiccant Evaporative Cooling systems. The process makes it possible to closely tailor the amount and characteristics of the Silica Gel in the rotor.

This method is inefficient when the ambient temperature is under 10°C, because you need either cold water which mean above 0°C to be sure that it will not turn to ice, either frigorific fluid to go lower but take the risk to turn into ice the water from the air. Frigorific fluids are also less environmentally-friendly because it involves the use of HCFCs and this method is more maintenance-heavy mainly due to freezing issues. This alternative is actually a good combination with a desiccant rotor dehumidifier because it can cool down the air and the absolute humidity by condensation and the desiccant rotor will also decrease the absolute humidity and increase the temperature so it will decrease the relative humidity even more efficiently.

The capacity, pressure drop and other characteristics of the Dessica Silica Gel rotors can easily be calculated in our software program.

There are an enormous number of applications for desiccant rotor dehumidifiers. Many of these relate to the food processing and associated industries, including industrial bakeries. However, there are plenty of other fields where a desiccant rotor can help out. One of these is the protection of valuable artefacts in museums, art galleries, libraries and archives. These range from old books and costumes to upholstery and even classic cars! Ice rinks also use this kind of technology to ward off fog, puddles and musty odours. Another unusual area where a desiccant rotor of the DESSICA silica gel rotors type could potentially help out is with seed storage & preservation, where germination is public enemy number one.

Material Composition: The rotor has a very high, 82%, active SilicaGel content and only 16% glass fibre content, the remaining 2 % is the Acrylic surface coating.
Fire resistance: The rotor has been tested according to ASTME test E-84 and achieved a flame index of 0 and a smoke produced of 0.
Technical properties: There is no limit for how high relative humidity the rotor can stand as long as droplets are not introduced into the rotor during operation. The rotor can be washed in water with weak non-alkaline detergent, after saturation in humid air.
Physical properties: The density of dry material is approx. 240 kg/m3. The media can pick up approx. 40% of it’s dry weight as moisture in humid environment. The surface compression strength of the rotor is more than 200 kPa.

On request DESSICA produce replacement rotors in sizes to fit most existing dehumidifiers.