Separators

A separator comprising an outer cylindrical first vessel and an elongate unit including a spiral baffle forming a spiral passage in said unit, the spiral baffle having at least two concentric coil portions which extend over a height of said first vessel with an innermost end of the baffle having a cut-away portion which extends from below an upper surface of said baffle on a slope away from the innermost end of said baffle toward a bottom surface of said baffle, the first vessel having a sump and the elongate unit being in fluid communication with the first vessel, an inlet means being provided to convey a mixture into the assembly to be separated, and a first outlet means and a second outlet means being provided through which the separated components of the mixture are separately removable from the assembly, the mixture passing through the first vessel and a spiral passage of the elongated unit with a disposable component of the mixture being discharged through the first outlet means and a residual component of the mixture being held in the first vessel from which it is periodically removed through the first or the second outlet means.