Two different types of contaminants may seriously affect the quality of compressed air:

• atmospheric contaminants
• plant contaminants

Regarding atmospheric pollution, a cubic metre of urban compressed air at 7 bar can contain one thousand million particles, including fine dust (combustion particles) gas and hydrocarbon vapour originating from industrial discharges. Contamination of the air system occurs because compressors and fittings can produce rust particles, waste and lubricating oil sludge.

Even “oil free” compressors have this problem, as they compress gases, oil vapours and fine particles contained in the polluted atmosphere and then transfer them to the condensate in the air system. Contaminants produce corrosive emulsions obstructing the pipelines, increasing the pressure losses (and consequently the manufacturing costs), such emulsions may clog and wear out pneumatic tools and sometimes also the air system is blocked.

Mattei, a market leader in compressed air technology, supplies a wide range of high efficiency filters to eliminate impurities and contaminants in all industrial applications of compressed air. Particularly, Mattei filters ensure the air is up to 99,99% technically oil free by the use of specific materials.