Process and apparatus for adding particulate solid material to molten metal

This invention relates to a process and apparatus for the treatment of molten metals and, more particularly, the addition of salt flux to aluminum in melting and holding furnaces. It is claims the benefit of Provisional Application Serial No. 60/232,071, filed Sep. 2, 2000. An apparatus is provided for the treatment of molten metal, e.g. aluminum, with a particulate treatment agent and a gas. This includes a vessel for holding molten metal, a rotary device for breaking up particulate treatment agent and gas within the molten metal and for dispersing particulate treatment agent and gas within the molten metal contained in the vessel and means for supplying the particulate treatment agent and gas to the rotary device. The rotary device includes a hollow shaft having a rotor with an axial opening fixed to the discharge end of the shaft, this rotor being in the form of an annular plate with a plurality of radially mounted upwardly directed blades projecting from the top face of the annular plate and a plurality of radially mounted downwardly directed blades projecting from the bottom face of the annular plate.