An apparatus for separating hydrocarbons from water, comprising a tank segment with a fluid inlet subsequent a housing with a liquid-gas mixer. The fluid inlet through a cylindrical tank wall, and further through the wall of a conical wall segment, a pipe spread, combining radial and axial flow over ring mounted guide vanes at the upper part of the conical wall segment. A hydro carbon outlet is located at a top end and a water outlet at a bottom end of tank-segment. A pipe for scale and debris removal is connected to the lower part of the bowl. The inner conical wall segment extends to the top end of the tank segment and at this location comprises a ring of vertically mounted guide vanes.