Method and apparatus for gaseous cleaning of aluminum

Claim 1

Improved apparatus for sparging molten metal comprising, in combination: a sparging box having opposite sides partially defining a flow channel for molten metal, an end with a molten metal inlet at said end and an opposite end with a molten metal outlet at said opposite end, said box also including an open top and a base assembly extending between the sides and ends to define the flow channel, said base assembly including a generally planar, horizontal surface defining an internal surface for the box; a plurality of removable, vertical, spaced baffles in the box extending between the sides, transverse to the direction of metal flow through the box, alternate ones of said baffles supported from the top and spaced from the base, the remaining intermediate baffles resting on the bottom surface and extending partially from said bottom surface upward to define a serpentine pathway for the metal flow through the box; and said base assembly also including a shaped, gas permeable block in the assembly, said block permeable to a sparging gas flow, said block having a portion thereof defining a plurality of discrete, surface areas for discharge of sparging gas into a molten metal stream in the box, said surface areas lying in the plane of the bottom surface; and said block including means for transport of a gas flow through the block.