Provided is an assembly including a vessel having first and second ends and an interior, an inlet diverter disposed in the interior at the first end, at least one flow baffle disposed in the interior and having a gas section including a plurality of gas openings extending through the baffle, a liquid section below the gas section including a plurality of liquid openings extending through the baffle, and a bottom surface spaced from a bottom interior surface of the vessel to define a fluid flow path between the bottom surface and the bottom interior surface, and at least one vane section disposed in the interior downstream of the at least one flow baffle, the at least one vane section having a bottom surface spaced from the bottom interior surface of the vessel to define a fluid flow path between the bottom surface and the bottom interior surface.