Aluminium recovery from furance residue or scum - where hot scum is mixed with flux on bath of molten aluminium

摘要

Process for treating aluminous matl. consisting of furnace scum, dross, or metallic residues, using salt fluxes, in which the aluminous matl. is charged into a layer of molten flux floating on top of liq. aluminium and the matl and the flux are stirred so that practically all the malt in the matl. is transferred to the liq. aluminium. The aluminous matl. is pref. at min. 500 degrees C. when charged, esp. scum taken directly from a furnace without any appreciable cooling. Pref. flux is a mixt. of chlorides of alkali- and/or alkaline earth-metals, and liq. above 675 degrees C. Very high yields, e.g. above 95% can be obtd. in recovering Al from the scum.