Sales and Service of Pumps, Motors, and Compressors Since 1918
CALL US 800/289-0500
Seattle: 206/762-0500 Spokane: 509/534-3559 Portland: 503/788-2850 Boise: 343-2076 Anchorage: 907/222-3200
Cascade Inventory Warehouse Dealers: Kodiak: 907/486-5350 Dutch Harbor: 907/581-2900 Naknek: 907/246-4230
Home / Products / Parts & Supplies / Accessories / DS Oil/Water Separators

DS Oil/Water Separators


As one of the world’s leading manufacturers of compressed air purification equipment in the world, Donaldson has built a comprehensive engineering, manufacturing, and customer support network to meet the most demanding applications. With over 30 years of expertise in compressed air filtration and separation technologies, Donaldson manufactures a complete line of oil/water separators to effectively and efficiently separate oil from compressed air condensate.

The need for condensate management occurs when liquid condensate is generating at several points throughout a compressed air system, including the outlet of the compressors itself, within accumulator tanks, cyclone separators, coalescing filters and refrigerated air dryers. Whenever condensate forms, it must be removed from the compressed air system and discharged in a manner that is both environmentally sound and economical.

The amount of condensate generated within a compressed air system can be surprising. As an example, a 500 scfm system operating in ambient conditions of 60°F and 65% relative humidity can generate nearly 2 gallons of liquid condensate per hour. That condensate, however, will be generated at a number of points within the system. All of this condensate must be removed from the compressed air system. This is accomplished with the use of drain valves.*

When oil is present, as with oil lubricated compressors, the condensate must be purified to legal levels of residual oil content before it can be discharged to public water treatment systems. Typically, condensate will contain on the order of 5% oil. That level must be reduced to 20 ppm or lower, depending on local ordinances.