Oil is present in the compressed gases downstream of Oil-Flooded Screw or Lubricat- ed Reciprocating Compressors. To improve compressor efficiency,this oil must be re- moved to finite levels. This is possible only by the use of successive stages of coalescing oil separators followed by charcoal adsorber. Typically for 10ppbw or less oil carry- over limit,three stages of coalescing,followed by a charcoal adsorber is required. Coalescing separators remove the oil droplets;whereas the charcoal adsorbers remove the vapor phase oil. Special Micron Filters are employed downstream of adsorbers to catch particulates from the charcoal.
- Oil-free compressed gas is available from versatile Oil-Flooded Screw Compres- sors or longer life Lubricated Recip. Compressors when an “ORS: is employed downstream of the compressors.
- An ORS will permit the use of higher compression ratios per stage of compression when an oil-flooded or lubricated compressor is used instead of a dry or an oil- free compressor.