Recovery system

Claim 2

A continuous process for recovering aluminum from aluminum foil scrap comprising the steps of receiving bales of aluminum foil scrap on a belt conveyor, dropping said aluminum foil scrap into a shredding machine to separate same into individual fragments, conveying said aluminum foil scrap fragments by an air conveyor to a cyclone, separating scrap fragments from the air stream, passing said scrap fragments through an air-tight lock, passing said fragments into a nonoxidizing atmosphere furnace maintained at a pressure slightly above atmospheric pressure and containing a plurality of hearths, the first hearth being maintained at a temperature from about 900* F. to about 1,110* F., the second and third hearths being maintained at temperatures from about 900* F. to about 1,000* F., and the lower hearth being maintained at a temperature of about 700* F., rabbling the fragments sequentially over said hearths to separate out volatile organic material leaving metallic aluminum and solid loosely adherent carbon and ash, feeding controlled amounts of air above said hearths to burn the separated out volatile organic material in said furnace at locations remote from the remaining material, passing the remaining material, including about 90 percent aluminum and about 10 percent carbon and ash, through a mechanical separator for crushing the material and separating out the carbon and ash thereby to provide high grade aluminum material.