| CA |
In 100 m3 of compressed air you could find 2.2 litres of water (75% in liquid form and 25% as a vapour), 2 grams of oil, 8 million solid particles and odours from the air that are drawn in by the compressor and the compression process.
NOTE: This data is correct for air at 30 0C with a relative humidity of 70% at 700 kPa.
Water, oil, particles and odours will be troublesome in certain processess and can affect the quality of the work being carried out. These impurities can corrode pipes and equipment that use compressed air, thereby decreasing their ability and increasing maintenance expenditure.
Air leaving a compressor is seldom suitable for use without it requiring some treatment to purify it. The type of treatment required is dependant on the applictaion or use that is to be made of the air.
In the schematic layout below, a number of components relating to the compression, storage and conditioning of air as well as the treatment of the resultant contaminated condensate are identified. The sequence in which these components are installed is important and should be carefully noted. |
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| The table below lists typical compressed air applications. |
| AIR QUALITY/APPLICATION |
RD=Refrigerated dryer
(dew point +3 0C) |
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AF=Adsorption dryer
(dew point -20 -40 0C) |
GENERAL PURPOSE COMPRESSED AIR
liquids & solids - bulk contamination removed air for general
industrial use; pre-filtration for refrigerated dryer |
Condensate Separator |
QF |
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MEDIUM QUALITY COMPRESSED AIR
industrial sandblasting; industrial spray painting; large
pneumatic tools; low-cost automation; tyre inflating;
pre-filtration for absorption dryer |
Condensate Separator |
QF |
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PF |
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DRY, MEDIUM QUALITY COMPRESSED AIR
high-quality sandblasting; quality industrial spray painting;
standard pneumatic tools; air motors; air cylinders |
Condensate Separator |
QF |
RD |
PF |
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DRY, GOOD QUALITY COMPRESSED AIR
high quality spray painting; high speed and miniature pneumatic
tools; air bearings; air gauging; robotics; instrumentation;
dental machinery; photo labs |
Condensate Separator |
QF |
RD |
PF |
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HF |
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ODOURLESS, DRY, HIGH QUALITY COMPRESSED AIR
pharmaceutical; food stuff; brewery; production/packaging;
P.E.T. Bottle moulding; decompression chambers; medical
equipment; advanced pneumatics; air blast circuit breakers;
critical instrumentation |
Condensate Separator |
QF |
RD |
PF |
|
HF |
CF |
VERY LOW DEW POINT COMPRESSED AIR
systems requiring a dew point lower than 3 0C at pressure |
Condensate Separator |
QF |
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PF |
AF |
PF |
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| AF=Adsorbtion Dryer
CF-Carbon Activated Filter
HF=Coalescing Filter
QF=Prefilter
PF=Coalescing Filter
RD=Refrigerated Air Dryer |
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