Adsorption technology
July 01st 2008

Eliminating moisture and foreign gases is essential to provide dry, clean and oil-free compressed air. Donaldson Filtration runs through the types of adsorption dryers available.

Twenty five metres long, six metres wide and seven metres high: These are the dimensions of the largest system segment delivered from the Donaldson workshop in Haan. And this segment was just one of several parts of the adsorption dryer unit that was installed in a large chemical plant which now processes 66,000 Nm3/h of compressed air. Adsorption technology even withstands the test with extremely large flow rates to eliminate moisture and foreign gases from compressed air and technical gases.

In the case of standard applications, standard adsorption dryers are used. Donaldson offers a range of products from the economic and compact ‘terminal dryers’ through the new highpressure dryers up to the highly efficient heat regeneration ‘heat of compression’ adsorption dryers.

With this range of products, nearly all requirements of compressed air processing can be covered to provide dry, clean, and oil-free compressed air even for challenging applications such as semiconductor production. There are, however, applications where the systems must be individually adapted to the operational conditions – and exactly this is the task of our business division ‘Systems Dryer’.

PROCESSING OF TECHNICAL GASES

Special installations are for example required if – as described above – extremely large amounts of compressed air must be processed. One single tailored large-scale system performs this task much more economically than several standard dryers. Frequently, the engineers of the Systems Dryer division also develop solutions for processing technical gases and gaseous energy sources such as carbon dioxide and natural gas. For this they have up-to-date CAD systems at their disposal, and since the engineers work close to the dryer production department short ways between engineering and production are guaranteed.

OPTIMUM INTEGRATION INTO THE SYSTEM

Independent of the medium to be processed, an optimum integration of the dryer into the total system requires comprehensive know-how. Klaus Michel, Technical Manager says: “If the adsorption system is individually developed, it is often possible to remove the regeneration gas as well as the required regeneration heat from the process – thus saving lots of energy. Therefore, the additional costs for a special installation often amortise in a very short period of time. And the extensive experience that we have gathered during many years of systems engineering, ensures that the systems optimally fulfil their tasks.

Therefore, we often take unconventional paths and for example build systems with three adsorption vessels in order to conserve the adsorbents and guarantee long regeneration cycles.”

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