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Dross Processing
The furnaces used for melting recycled aluminum generate three products. The
rst is the molten aluminum, which is cast or transferred to customers. The second
is the off-gas, which will be discussed in the next chapter. The third is a semi-
solid skim removed from the melt surface. This skim, better known as dross, is a
mixture of molten aluminum metal and various oxide and chloride compounds.
Its composition depends on the choice of melting practice and the amount and
composition of uxes used. Regardless of composition, the processing of dross
has always been important. Dross processing can (a) recover the valuable meta ...