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 snorkel (10) having a double shell core (16, 26) that defines an annular gap (40) between the shells and that has an array of baffles (66) arranged in the annular gap to define a serpentine flow path for cooling gases that pass through the annular gap. In an embodiment, a snorkel includes a flange (12) that defines an internal passageway (84) such that the fluid pathway through annular gap (40) includes passage of cooling medium through internal passageway (84).

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 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.

The invention relates to a system and method for bottom electrode compound bottom blowing of multi-media of DC electric arc furnace, which belongs to the field of steelmaking technology. The system includes a plurality of bottom electrodes located at the bottom of furnace, wherein some of the bottom electrodes are bottom blowing electrodes with hollow structures, and some of the bottom blowing electrodes are at least one type of Type I bottom electrode, Type II bottom electrode and Type III bottom electrode; the Type I bottom electrode is used to blow carbonaceous materials into the molten pool to carburize the molten pool to accelerate scrap melting; the Type II bottom electrode is used to blow slagging powder into the molten pool to form molten slag particles in the molten metal to increase the gas-slag-gold three-phase reaction interface area during the dephosphorization reaction; the Type III bottom electrode is used to blow gas into the molten pool to accelerate mass transfer in the molten pool; the system also includes a control unit connected to the bottom blowing electrode to realize online adjustment of the blowing parameters in combination with the power supply intensity of the bottom blowing electrode during the smelting process. The invention can improve production efficiency and reduce consumption of raw and auxiliary materials.