High alumina cement is produced in a submerged combustion melter, cooled and ground.

A degassing launder having a plurality of partition plates configured to block a flow of molten aluminum and including a plurality of domes. Two adjacent partition plates and two side walls of the launder form a degassing chamber. A lower portion of the partition plates is provided with a passage through which the molten aluminum flows into a next degassing chamber. The domes are arranged on the bottom of the launder.

This electric furnace includes one or more upper electrodes, one or more bottom-blowing tuyeres, a mechanical stirrer equipped with an impeller, and a charging device which injects an iron oxide-containing iron raw material.

A device includes a molten metal pump and a metal-transfer conduit. A clamp may be used to attach the metal-transfer conduit to the pump. The pump has a pump base including an indentation configured to receive the metal-transfer conduit and align the pump outlet with the transfer inlet. The pump outlet may be formed in the indentation and preferably near the center of the indentation in order to better align with the transfer inlet. As the pump operates it moves molten metal through a pump outlet that is in communication with a transfer inlet in the metal-transfer conduit. The molten metal enters the transfer inlet, moves upwards in a passage in the metal-transfer conduit, and out of a transfer outlet.

High alumina cement is produced in a submerged combustion melter, cooled and ground.

A multiple chamber material-stirring lance and method used to treat molten metal in a ladle, the lance having a stirring gas chamber, and a plurality of gas permeable ports arranged at a terminal end of the gas chamber, and at least one material chamber positioned parallel to the gas chamber and terminating in a plurality of material ports. In use, the multiple chamber material-stirring lance is lowered into the ladle of molten metal, and gas and material are both introduced into a respective chamber and emitted through their respective ports. Stirring gas emitted through the gas permeable ports under a gas pressure between 40 and 600 cfm causes the stirring gas to create a boiling effect in the molten metal, drawing material into the stirring gas bubbles and away from the lance body, improving material dispersion efficiency and thus impurity extraction from the molten metal.

A molten metal processing apparatus selected from a pump, a degasser, a flux injector, and a scrap submergence device constructed to include at least one element comprised of C/C composite.

A metal melting apparatus capable of providing a clear melt with little oxides, even when either one or a mixture of scrap material and fresh material is supplied. Solution is provided by a metal melting apparatus including melting chamber to which a melt raw material is supplied, and gas injection system for injecting gas into melt in the melting chamber to generate a vortex of melt in the melting chamber.

A refining vessel for high-temperature melt includes a refractory for gas blowing nozzle that includes a central refractory embedded with metal tubules, and an outer refractory circumferentially surrounding the central refractory. The refractory for gas blowing nozzle has a horizontal projection on which a minimum radius of an imaginary circle encompassing all the metal tubules embedded in the central refractory is R (mm), wherein the central refractory has an outline that falls between one circle that is concentric with the imaginary circle and has a radius of R+10 mm, and another circle that is concentric with the imaginary circle and has a radius of R+150 mm. The central refractory is formed of a MgO—C refractory having a carbon content of 30 to 80 mass %, and the outer refractory is formed of a MgO—C refractory having a carbon content of 10 to 25 mass %.

A gas injection nozzle refractory with one or more gas injection small metal tubes buried therein has improved durability. The gas injection nozzle refractory includes a MgO-C central refractory with a small metal tube buried therein, and a MgO-C peripheral refractory surrounding the central refractory. The central refractory on a plane of the gas injection nozzle refractory has an external shape of a circle with a radius in the range of R+10 to R+150 mm concentric with a virtual circle with a minimum radius surrounding all buried small metal tubes, R mm being a radius of the virtual circle.