Patent ID: 7648558

Claim:
A method for treating aluminum in a furnace, said method comprising: a) introducing a material into a furnace, wherein said material comprises aluminum; b) melting said material with heat from at least one burner, wherein: 1) said burner is supplied with at least one oxidizer and at least one fuel; and 2) said oxidizer comprises at least about 10% by volume of oxygen; c) obtaining molten aluminum; d) measuring the concentration of a first gas in the furnace atmosphere or in a flue gas exiting said furnace, wherein said first gas comprises at least one member selected from the group consisting of: 1) hydrogen; and 2) carbon monoxide; and e) reducing the oxidation of said molten aluminum, wherein: 1) said reducing the oxidation comprises holding the flow rate of said oxidizer substantially constant while varying the flow rate of said fuel according to the concentration of a second gas in said furnace atmosphere or in said flue gas; 2) said second gas comprises at least one member selected from the group consisting of: i) metal oxide hydrogen; and ii) metal oxide carbon monoxide; and 3) said concentration of said second gas is calculated based on the difference between a measured species concentration and an intrinsic species concentration which would be present from the combustion of said fuel and said oxidizer in the absence of said material in said furnace.