Improved process of melting down and remelting old aluminium, aluminium scrap, residues, dross and ashes

摘要

520,533. Refining aluminium. SCHMIDT, K. Oct. 24. 1938, No. 30722. Convention date, Oct. 27, 1937. [Class 82 (i)] A process of melting down aluminium scrap, residues, dross and ashes consists in forming in a rotary furnace, a salt melt consisting of a mixture of sodium and potassium chlorides in proportions such. that the mixture fuses at not more than 750‹C., and introducing into the molten bath approximately the same amount of aluminium, after melting and tapping of which the bath is re-used up to five times. The salt mixture may consist of approximately 56 parts of sodium chloride and 74 parts of potassium chloride, melting at 664‹C. The exhausted salt bath is tapped, ground after solidification, separated from metal particles, leached with water, and recovered by evaporation, after which it is re-used after the loss in salt has been made good.