When drying a water damage there are two main principles – adsorption or condensing. What kind you should choose depends on a number of factors such as the air temperature and the relative humidity, the importance of low energy consumption and many more. In short, you can say that an adsorption dehumidifier / desiccant is of better use in cold, unheated spaces while the condensing dryer works best in higher temperatures with higher relative humidity.
We list the different techniques and their advantages below but first we want to describe the terms static and dynamic dehumidification.
Containers with drying agents (desiccants) are an example of static dehumidification. The drying agent adsorbs the moisture. In time it becomes saturated with water. The drying agent has to be regenerated in order to regain its ability to adsorb.
A dynamic dehumidifier is designed to supply a constant flow of dry air and the drying agent is regenerated constantly.
Silicagel is a crystal that can adsorb a lot of moisture, around 40% of its own weight.
Because of the pore structure, one single gram of Silicagel has a total inner drying surface of 200-700m2
ADSORPTION DEHUMIDIFIER / DESICCANT
- Dynamic dehumidification:
In many cases one is dependent on a constant flow of dry air, i.e. dynamic dehumidification. This can be achieved by a rotating adsorption dehumidifier and the
regeneration process is then continuous. Corroventa’s adsorption dehumidifiers are constructed based on dynamic dehumidification principle.
- The air passes a filter and then dryer rotor where the drying agent is located. The dehumidified air then goes via the dry air outlet to the area that is to be dried (see picture below)
- The adsorption dehumidifier works better in unheated, colder spaces, 0–20 °C
- Works best in cases where moisture has penetrated deep into the material structure because adsorption technique will dry deeper and with a lower RH.
- Gives some extra heat to the room
- Can be used together with a turbine and a water separator when e.g. drying layered constructions.
- Air flow in the room should be 1-2 times per hour.
- Water is cooled down to dew point and condensation water is deposited and gathered in a bucket.
- Most effective in areas with a higher temperature, 15-30 °C
- Simple to install! Perfect when the drying process needs to get started very fast.
- Can be used together with the axial fan AX 3000.
- Air flow in the room should be 3-4 times per hour
- Good to use in living environments, for emergency actions in the event of floods or in spaces where it is difficult to get rid of the wet air
THE DIAGRAM BELOW SHOWS THE TYPE OF DEHUMIDIFIER THAT WORKS BEST IN EACH CLIMATE
Adsorption dehumidifier – superior performance in the red area. Also works in the yellow and blue area.
Adsorption dehumidifier with condenser – excellent performance in the whole dotted area.
Condensing dryer – superior technology in the blue area. Does not work in the red area.
The yellow area is a transition zone.
The diagram above shows the capacity at 20 °C. Example of basic differences between selecting a condensing dryer or an adsorption dehumidifier.
The diagram above shows the difference on the dry air quality at 20 °C.
DO YOU WANT TO LEARN MORE?
Corroventa Academy offers courses for beginners and for you who has worked some years in the industry within drying techniques and moisture theory.