Abstract: A separator for removing oil-like substances from water using vertical columns of coalescing media to then enhance separation of the two phases. The coalescing media is an inert packing material having surfaces to enhance coalescing without significant resistance to flow. Final oil removal is achieved by a vertical column of charcoal pellets. The separator is of particular value in the processing of oil/water discharges from air compressing systems. This produces water that can be discharged in an environmentally safe manner to conventional sewers, etc. The oil is held in a convenient storage vessel for ultimate disposal. No pumping devices are needed in the separator as flow is provided either by the pressure in the outlet from the compressor system, or by gravity from a feed tank. The vertical columns are arranged within a cylindrical vessel to minimize floor space and plumbing. The oil concentration in the product water is below current EPA standards.