Compact adsorption dryers for situations that demand very low RH

The ASE series is flexible in its use thanks to its compact and lightweight models. These models offer an impressive dehumidification capacity, even at low dew points.

When to use adsorption dryers?

Adsorption dryers are used when:

    • very low relative air humidity of less than 35% is required (e.g. pharmaceutical and chemical industry, ammunition depots, etc.)
    • low temperatures cannot be avoided (e.g. refrigeration rooms)
    • low temperatures are necessary or climatologically determined (e.g. tank coatings, ship cleaning)


    Operates more efficiently at temperatures below 10 °C than condenser dryers

    Compact and light models with high capacity

    Adsorption principle with one common fan for process and regeneration air

    Hose connection available

    Operates more efficiently at temperatures below 10 °C than condenser dryers

    Compact and light models with high capacity

    Stainless steel models available for special hygienic standards

    Hose connection available

    Power consumption of adsorption dryers

    At a temperature of 12 °C, the power consumption of a condenser dryer is about one third of the power consumption of an adsorption dryer for the same dehumidification demand. A condenser dryer requires a much lower electric connection voltage which is important from an energy-efficiency perspective. The tipping point where an adsorption dryer becomes more efficient than a condenser dryer is approx. + 7 °C (the average annual temperature in the Benelux is + 10.7 °C).

    ATTENTION:In construction drying, temperatures below 7 °C are only theoretical because vapour diffusion from the construction materials is barely a factor anymore.

    Use of adsorption dryers in the case of fire damage

    Plastics are incorporated into everyday products more and more which poses severely underestimated problems in case of fire. Rather than damage caused by extinguishing water, the biggest problem is the exceptionally aggressive hydrochloric acid vapour that forms when polyvinyl chloride (PVC) burns and reacts with humid air.

    When 1 kg of PVC burns with a chlorine percentage of 50%, approx. 0,4 m³ of hydrogen chloride gas forms which gives a concentration of 30% hydrochloric acid when dissolved in 2 litres of water. If the right measures are not taken immediately, hydrochloric acid rains down on all unfinished metal surfaces (coatings are often burnt), e.g. machines, tools, electrical installations, etc., resulting in corrosion damage.

    This is why the cause of hydrochloric acid formation needs to be removed immediately. This means that the chemical reaction between hydrogen chloride gas and the humid air must be stopped. Corrosion can be halted by reducing the air humidity to 30% RH.

    That is why Dryfast recommends to deploy adsoption dryers for fire damage removal or, alternatively, the new Dryfast DF800 construction dryer with a hose connection piece for two hoses. Drying must be started immediately after completion of extinguishing activities; the quicker dehumidification begins, the lower the clean-up costs will be. Depending on the volume of the room, it is decided whether the entire room is dried or only the objects it contains. When drying the entire room, the relative humidity in the room is reduced to below 30% RH in the shortest possible time in order to interrupt the chemical process of hydrochloric acid formation. If the room cannot be dried due to economic or technical reasons, e.g. because only a few objects are at risk, these are covered with construction foil, for example, and locally dried underneath.