Method and apparatus for cleaning and drying metal chips

Abstract

There is disclosed a process for producing dried and cleaned metal chips by entraining metal chips in a gas, introducing the gas into a cyclone separator having a wall heated to fluid-vaporizing temperature by combustion effected in a surrounding chamber, purging fluid from said chips, exhausting hot gases and exiting dried metal chips from said separator, conducting hot gaseous products of combustion from the combustion chamber to a continuous centrifuge, extracting extractable fluid from starting metal chips, which may be previously uncleaned and/or unwashed, in the centrifuge, entraining the chips in the hot gaseous products of combustion introduced into the centrifuge, and conducting the gaseous products with entrained chips from the continuous centrifuge to the cyclone separator, thereby providing an essentially closed system. The combustion chamber may be a part of an afterburner furnace and hot gases entraining vaporized oil exhausted from the cyclone separator may by recycled and employed as fuel for the combustion chamber. This particular disclosure emphasizes provision in the system of hot water and/or steam from either an external source or from a water jacket around the cyclone separator, preferably together with solvent and/or detergent, and a final chip drying step wherein the drying is effected using products of combustion which are enroute back to the continuous centrifuge. Apparatus for carrying out the said process is also disclosed.