A modern and energy efficient approach to compressed air drying
November 10th 2008

Compressed air is heavily used in the engineering and production environment, but is often wet, oily and dirty – properties that are not welcomed in the electronics or pharmaceutical industries, or in processes such as paint spraying.

As air is compressed, large volumes of wet atmospheric air are drawn into the compressed air system. When cooled in storage vessels and distribution piping, water vapour condenses into liquid water, making this the major contaminant.

Solid particles and oil can be removed by filters, but water vapour has to be removed by a dryer. Refrigeration systems can only guarantee dry air provided the ambient temperature never falls below, typically, +3°C. Applications requiring clean, dry air, to temperatures as low as -70°C pressure dewpoint have to use desiccant dryers.

PNEUDRI - proven technology

Conventional dryers are designed as welded steel pressure vessels and as such, suffer from the inconvenience of having to be inspected annually for insurance purposes, which means taking them out of service. Parker domnick hunter engineers developed a modular dryer that is typically 60% the size and weight of conventional designs.

The PNEUDRI range uses a single, high tensile aluminium extruded section, and is of modular design which eliminates the need for complex valves or interconnecting pipework. More importantly, the length to diameter ratio of the internal voids has been selected so that the dryer, which can operated at pressures up to 13 bar g (190 psig), avoids the requirement for insurance inspection due to its non-welded construction.

Any size of system catered for

These extruded aluminium columns are bolted together in such a way that additional units may be added to increase compressed air capacity, facilitating further plant expansion.

Multi-banking dryers enables individual banks to be easily isolated for service/maintenance work, or even a decrease in air capacity requirements (eg night shift). This facility allows service/maintenance work to be carried out with minimal interruption to the clean air supply.

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