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Desiccant air dryers

Complete range of twin tower desiccant air dryers and rotary drum dryers for all industrial applications

Protecting your systems and processes

Desiccant air dryers provide the ultimate in energy efficiency and supply extremely low dew points

For a broad range of industrial applications

Complete range of desiccant air dryers for a broad variety of industries and applications with dew points down to -70°C / -100° F

Protect your production

Our patented Elektronikon control and monitoring system takes continuous care of your desiccant air dryers to ensure optimal productivity and efficiency at your site

How does a desiccant air dryer work?

Twin tower desiccant air dryer working principle

Adsorption dryers are used when the compressed air application requires a pressure dew point below 0°. The regenerative desiccant dryers consist of two pressure vessels. Both vessels are filled with desiccant. One vessel is removing moisture from the compressed air.

Wet air passes directly through the desiccant bed which adsorbs the moisture. When this vessel is saturated with moisture the valves will switch and lead the air to the other standby vessel. During adsorption in the other vessel, the first vessel will be regenerated. It's a cyclic process.

The desiccant medium has a finite capacity for adsorbing moisture before it must be dried out, or regenerated. To do this, the tower containing saturated desiccant medium is depressurized and the accumulated water is driven off.
How this happens depends on the type of dryer.

Heatless dryers use only compressed air as a purge
Blower purge dryers use a combination of air from an external blower, heat, and minimal compressed air
Blower zero purge dryers use a combination of air from an external blower, heat, and zero compressed air
Heat of compression dryers use the heat of the compression
Heated purge dryers use heat and small amount of compressed air

Types of desiccants

Depending on the technology and dew point requirement, there is always the best choice of desiccant, sometimes a combination of multiple layers of desiccants used in our designs. In this way, we will ensure required PDP levels and maximized lifetime for desiccant.

Rotary drum dryer working principle

structured desiccant rotary drum dryer

The rotary drum dryer also uses adsorption technology. The desiccant does not come in granular form. Instead, it is bonded with a binding material in a honeycomb structure. The main advantages are:

No erosion of desiccant beads
No escape of beads

This unique technology does not require any additional energy, as it is using the heat of compression. The rotating drum is divided into sections. In general 3/4 of the drum is used for adsorption, while 1/4 is used for regeneration. It's a continuous process as the drum rotates and therefore doesn't require any switching valves.

Complete desiccant air dryer range

BD+CD+XD+ twin tower desiccant air dryers

Highly energy-efficient desiccant air dryers. For intensive, constant use. Ideal for critical processes, including oil-free, from 25 to 3600 l/s.

CD+ Desiccant compressed air dryers with Cerades technology CD+ 20-335

CD+ with Cerades™

The first dryer to use the revolutionary Cerades™ desiccant developed and patented by Atlas Copco.

MDG & MD & ND rotary drum dryers

The MDG, MD & ND are highly cost-effective rotary drum dryers. Constant supply of dry air, extremely low power consumption. For oil-free air applications.

CO2 removal unit

For applications requiring dry and CO2 free air, our CO2 removal unit protects your compressed air systems and maintains the quality of your end product.

Desiccant air dryers

Which type? A heatless desiccant dryer model 185 may have a lower purchase price but could cost you £10-14k per year more to run than the equivalent size of heated purge desiccant dryer with zero purge cooling (depending on running hours and electricity price)

A heatless desiccant dryer loses about 20% of output to purge. This is because if a desiccant dryer experiences a high pressure drop, the compressor discharge pressure must be set higher, which increases energy and operating costs. Therefore, it is important to select desiccant dryers that offer a very low pressure drop – below 0.2 bar for most models – as well as the most efficient regeneration process. A zero purge desiccant dryer does not lose any of its air output to purge and could save 20% in energy compared to a heatless desiccant dryer. Your output will be higher if you switch to a BD+ dryer!

How to chose an air dryer for your compressor?

How to chose an air dryer for your compressor?

the need for a refrigerated or desiccant dryer will be mainly dependent on the specific air quality requirements for a given process. Read more to see which technology is most suitable for your compressor and application.