Compressed Air: Application Areas

The screw compressor like in Fluid-Aire Dynamics for example is suitable for both intermittent and continuous operation. Thanks to modern technologies, the energy consumption of the screw compressor can be significantly reduced compared to previous methods. Liquid-injected screw compressors in single-stage versions currently dominate the sector – for an operating pressure of up to 13 bar.

Drying Compressors

The dry or “oil-free” screw compressor compresses air without cooling the compression chamber. The compressor operating temperature rises to 200°C. The drying compressor must compress the air in two stages and cool the compressed air between the compression stages.

5 Compressed Air Drying

The drying process in Air Compressor Inline Filter for example removes the moisture present in the compressed air. Dry compressed air reduces the risk of corrosion damage and lowers the cost of running connected tools. Drying is carried out using two methods: cold drying or adsorption drying.

Compressed Air Dryer

Adsorption Dryer

The adsorption dryer consists of two pressure vessels containing a desiccant, usually aluminum oxide, silicone gel, or a mixture of both. The compressed air passes through a chamber where it is dried when it comes into contact with the desiccant to a dew point of 25°C or less.

The adsorption dryer is sensitive to oil and water in the compressed air and must always be preceded by an oil and water separation filter.

Refrigeration Dryer

The cold dryer contains a cooling machine with a refrigerant compressor, a heat exchanger, and a coolant. The compressed air is cooled to a temperature between ± 0 and +6 °C. Condensation is precipitated and separated automatically.

The dryer is easy to install, consumes little energy, and is relatively insensitive to oil in compressed air. An oil separation filter is installed after the dryer to reduce the amount of residual oil in the compressed air.

6 Filtration Of Compressed Air

By installing filters in the compressed air system, it is possible to minimize the levels of pollutants to an acceptable level for the operational air or to eliminate them if necessary. Three different methods for the filtration of compressed air and gases: surface, depth, and activated carbon filtration.

Filtered Compressed Air

Surface Filtration 

A surface filter acts like a sieve. Particles larger than the holes in the filter element remain on the surface while smaller particles pass through.


The filter material can be cellulose fiber, polyethylene, or sintered metal in a surface filter.

Activated Carbon Filtration

Oil vapors and some gases are absorbed through a bed of activated carbon. Compressed air is, therefore, odorless and tasteless. This type of filter must always be preceded by a depth filter, in which the oil drops are separated. In addition, the compressed air must be dried using an air dryer before being filtered by the activated carbon.

Depth Filtration

Depth filtration separates oil and particles from the compressed air through a glass fiber filter. The oil droplets are trapped in the fibers. The fibers compress the oil and drain through a drain valve at the bottom of the filter housing. Solid particles are stuck between the fibers.