Disclosed are degassers, couplings, impeller shafts and impellers for use in molten metal. One such coupling transfers gas into an impeller shaft, the coupling having a smooth, tapered internal surface to align with a corresponding surface on the impeller shaft and help prevent gas leakage and to assist in preventing damage to the impeller shaft. Improved impellers for shearing and mixing gas are also disclosed, as is a degasser including one or more of these components.

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 system for melting a pelleted charge material including a furnace having a feed end configured to receive a solid pelleted charge material and a discharge end opposite the feed end configured to discharge a molten charge material and a slag, a conveyor configured to feed the pelleted charge material into the feed end of the furnace, at least one oxy-fuel burner positioned to direct heat into a melting zone near the feed end to heat and at least partially melt the pelleted charge material to form the molten charge material and slag, wherein the oxy-fuel burner uses an oxidant having at least 70% molecular oxygen, and at least one flue for exhausting burner combustion products from the furnace.

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 MgOC refractory having a carbon content of 30 to 80 mass %, and the outer refractory is formed of a MgOC refractory having a carbon content of 10 to 25 mass %.

A method of operating a BOF bottom stir tuyere having an inner nozzle surrounded by an annular nozzle, including during a hot metal pour phase and a blow phase, flowing an inert gas through both nozzles; during a tap phase, initiating a flow of a first reactant through the inner nozzle and a flow of a second reactant through the annular nozzle, and ceasing the flow of inert gas through the nozzles, wherein the first and second reactants includes fuel and oxidant, respectively, or vice-versa, such that a flame forms as the fuel and oxidant exit the tuyere; during a slag splash phase, continuing the flows of fuel and oxidant to maintain the flame; and after ending the slag splash phase and commencement of another hot metal pour phase, initiating a flow of inert gas through both nozzles and ceasing the flows of the first and second reactants.

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.

Disclosed are degassers, couplings, impeller shafts and impellers for use in molten metal. One such coupling transfers gas into an impeller shaft, the coupling having a smooth, tapered internal surface to align with a corresponding surface on the impeller shaft and help prevent gas leakage and to assist in preventing damage to the impeller shaft. Improved impellers for shearing and mixing gas are also disclosed, as is a degasser including one or more of these components.

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 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.