Abstract: A method of refining molten metal in a vessel by the reaction of oxygen with impurities in the molten metal comprises the steps of: a) ejecting at least one primary jet of oxygen from a lance positioned above the molten metal into the molten metal to react with impurities therein and to form a layer of molten slag; b) continuing to eject the primary jet of oxygen from the lance and thereby causing the primary bet of oxygen to pass through the slag layer into the molten metal; c) ejecting a plurality of secondary jets of oxygen from the lance, the secondary jet of oxygen travelling for a distance separately from the primary jet of oxygen; and d) entraining the secondary jets of oxygen into the primary jet of oxygen upstream of the entry of the primary jet of oxygen into the molten metal.

Abstract: A method of controlling total jet pressure from the head of a metallurgical lance for introducing gas into a volume of metal in a vessel. The lance head has at least one ejector, which has a nozzle located in a bore of the lance head and has an annular gas passage between at least one nozzle and the wall of the bore. The method proceeds by adjusting the annular gas velocity from a first Mach number to a second mach number to effect change of the total jet pressure.

Abstract: A metallurgical lance for introducing gas into a volume of molten material in a furnace includes a head having a bore extending therethrough, a mounting assembly at the head in the bore, and a nozzle detachably secured to the mounting assembly by a connection, the nozzle adapted to coact with a tool releasably engagable with the nozzle to insert and withdraw same from the lance head through the bore without dismantling the nozzle.

Abstract: A process is provided for the production of liquid ferric sulfate from finely-divided ferric oxide, sulfuric acid and water in a reaction system comprising at least one closed reaction vessel at temperatures ranging from about 120° C. to about 150° C. and pressures from about 25 psi to about 70 psi. Iron oxide streams are fed countercurrent to the ferric sulfate reaction product stream and to the sulfuric acid and water feeds. The continuity of the reaction is effected by re-circulating fractions while withdrawing a fraction of the liquid ferric sulfate having a trivalent iron concentration of at least 10% from the reaction vessel. Yield and efficiency are provided by controlling the rate of iron ore, sulfuric acid and specific gravity and by counter current cycling the waste stream from the reaction through the dilution water and use of a polymeric settling agent to remove unreacted iron content from the digester output.