Aluminum scrap reclamation

In an improved method of melting metal scrap in a recirculating system having a heating bay and a pumping bay wherein molten melting media is circulated from the heating bay to the pumping bay and back to the heating bay, the pumping bay having a housing having upper and lower portions therein of generally circular cross section, the upper portion containing a body of molten melting media, the improvement comprising:

• (a) introducing a supply of scrap metal to the melting media contained in the upper portion of said housing;
• (b) adding a supply of molten melting media to said body through a volute located in the lower portion of said housing, said adding being accomplished by action of an impeller mounted on a drive shaft extending through the upper portion of the housing, and rotating in the lower portion of the housing, the impeller fabricated from a zinc borosilicate frit;
• (c) controlling the flow motion of the body of molten melting media and the metal scrap in the upper portion of the housing by action of vanes mounted on said shaft to create a vortex in said body for mixing said scrap in said melting media;
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• (d) removing melted scrap and molten melting media at a rate substantially commensurate with their rate of introduction to the housing, the melted scrap and molten melting media removed through an opening located in the upper portion of the housing.

An improved method of melting aluminum scrap in molten aluminum comprising:

• (a) providing a body of molten aluminum in a housing for purposes of melting aluminum scrap therein, the housing being generally circular in cross section and having upper and lower portions, the upper portion having a downwardly converging wall;
• (b) introducing a supply of scrap aluminum metal to the molten aluminum contained in the upper portion of said housing;
• (c) adding supply of molten aluminum at a temperature in the range of 1325.degree. to 1475.degree. F. to said body through a volute located in the lower portion of said housing, said adding being accomplished by action of an impeller mounted on a drive shaft extending through the upper portion of the housing, and rotating in the lower portion of the housing, the impeller fabricated from a zinc borosilicate frit and having a substantially circular disc having blades extending substantially downwardly therefrom to a flat ring member having a circular shaped opening in the center thereof, the opening adapted to permit molten melting media to enter the impeller axially, the disc, blades and ring member cooperating to discharge the molten melting media therefrom radially at a relatively high velocity;
• (d) controlling the flow motion of the body of molten aluminum and the aluminum scrap in the upper portion of the housing by action of vanes mounted on said shaft to create a vortex in said body for mixing said scrap in said molten aluminum;
• and
• (e) removing melted scrap and molten melting media at a rate substantially commensurate with their rate of introduction to the housing, the melted scrap and molten melting media removed through an opening located in the upper portion of the housing.