Atlas Copco OSC Condensate Separators

The air compression process has a number of by-products, one of which is a large volume of condensate. Generally, this condensate is an emulsified combination of oil and water which, if left untreated, is extremely harmful to the environment. The Atlas Copco OSC range of condensate separators is designed to separate the oil from the water, allowing the water to be drained away in an environmentally-friendly manner. 

Atlas Copco Oil/Water Separators

Scope of Supply

  • Two stage condensate filtration with buoyant oleophilic and activated carbon filter media
  • Central decompression chamber with mufflers for the inlet of the condensate
  • Maintenance indicators to accurately identify when the filter needs to be changed
  • Supplied complete with one set of oleophilic (white) and activated carbon (black) filters



  • Multiple inlet manifolds for easy connection of several condensate lines into one unit.


Flow Diagram

Oil/Water Separators Flow Diagram

A continuous condensate filtration process

  1. Condensate enters through the mufflers and depressurizes in the expansion chamber.
  2. The emulsified oil-water mixture then enters tower A and seeps through the white oleophilic filter.       The filter absorbs the oil but not the water.
  3. The oleophilic filter floats on the water and absorbs any remaining oil from the surface. The additional weight of the oil causes the filter to gradually sink as it gets more saturated, which ensures that clean filter material is always in contact with the surface of the water.       The maintenance indicator at the top of tower A shows the status of the filter; as the filter is consumed, the stick sinks. The filter has to be changed just before it’s fully submerged.
  4. Significantly cleaner condensate flows from tower A to tower B.
  5. Tower B contains a bag of activated carbon pellets (contained in a bag) which absorb any residual oil from the condensate.
  6. Clean condensate exits from tower B with almost no residual oil content, enabling it to be discarded easily and safely.


Control and Monitoring

The OSC separators provide continuous oil/water separation performance throughout the life of the filter elements. To ensure continued performance the filters should be changed at the specified intervals using only Atlas Copco genuine service kits.

The condition of the oleophilic (white) filter media is indicated by the maintenance indicator which, when fully down, shows that the filter bag needs replacing.


Oil/Water Separators ConstructionConstruction

The OSC units consist of two, three or six towers (depending on the size of the unit) containing a combination of oleophilic (white) and activated carbon (black) filter bags. The towers are constructed from an oil-resistant plastic extrusion and are fitted with caps, through which the maintenance indicator passes.

The filter media is contained within a fabric gauze material in order to keep the material in place and to facilitate easy removal during service.

The inlet and outlet connections are by means of a screwed port, the size of which depends on the unit selected.


Features and Benefits

Feature Benefit
No standing or stagnant water Eliminates health risks and requires less cleaning
Unit does not rely on gravitational separation Unit is insensitive to vibrations, shocks and splashes
All models have large capacity condensate towers Reduce the risk of spillage if the system becomes blocked or if there is a sudden increase in inlet flow
Separation is based on filtration rather than gravitational forces and weir separation The density of the oil is not of significant importance in the sizing of the unit, multiple oil condensate can be separated and poly-glycol-based condensate can be separated (although some de-ration may be required)
No oil collection bottle is required No chance to ruin previously separated condensate if system malfunctions
No de-ration required for synthetic based condensates Simplified model selection and unit size minimised for low capital investment
Units fitted with maintenance indicator Accurate identification when the filter needs to be changed, eliminating the need for special tests
Simple but robust design Enables easy installation with no special set-up; easy and clean filter changeover
Discharge condensate contains little oil (less than 15 mg/l if serviced regularly) Water can be drained away to the foul water drain without contravening strict pollution regulations