Method of gas fluxing molten aluminium with impellers located one above the other and mounted on a common shaft

摘要

A method for gas-fluxing molten Al contg. impurities in a relatively compact container (10) comprises: (a) adding fluxing gas to molten Al (12) at locations (26) directly beneath each one of a number of dispersers (24) located one above the other in the Al wherein the gas comprises a reactive or halogenous and/or a non-reactive gas of Ar, N2 or a mixture thereof; and is added at greater than 0.05 SCFH of gas per lb of Al; and (b) rotating the small dia. dispersers at a substantial rate thereby directly shearing bubbles of the gas (28) formed in the molten Al to create a substantial interfacial area between the fluxing gas and the molten Al, and thus remove impurities from the molten Al.