Abstract: Apparatus and method for separating and removing oil and particulate solids from a dispersion of oil and particulate solids in water or a water-based liquid. During separation, the dispersion is fed under pressure into the inlet end of a plurality of upright coalescer tubes made of a single-layer of flexible, water-permeable fabric and is prevented from exiting through the outlet end of the tubes. The water passes radially through the fabric walls into a stilling chamber surrounding the coalescer tubes and exits through a clean water outlet while the solid particulates are retained on the inner surface of the fabric. The oil particles coalesce on the inner surface of the tubes, forming a layer of oil which migrates through the fabric's pores due to the pressure differential between the inner and outer tube surfaces and forms an oil layer on the outer surface of the fabric.