Abstract: The present invention provides a method for removal of boron from metal silicon inexpensively and extremely efficiently by a simple method, specifically, heating metal silicon containing boron as an impurity to its melting point to 2200° C. to place it in a molten state, then adding a solid mainly comprised of silicon dioxide and a solid mainly comprised of one or both of a carbonate of an alkali metal or a hydrate of a carbonate of an alkali metal into said molten silicon so as to form a slag and remove the boron in the silicon.

Abstract: A method of producing foamed slag in an arc furnace by measured blowing of a carbon carrier by means of an oxygen carrier into the boundary layer between the slag and molten metal layers or into zones of the slag or molten metal layer adjacent to the boundary layer in an amount such that arc are enveloped at least by a foamed slag layer.

Abstract: The invention relates to a process for the separation and recovery of non-ferrous metals from zinc-bearing residues, in particular from residues produced by the zinc manufacturing industry. The process comprises the steps of: —subjecting the residue to a flash or agitated bath fuming step, thereby producing an Fe bearing slag and Zn- and Pb-bearing fumes; and —extracting the Zn- and Pb-bearing fumes and valorising Zn and Pb; characterised in that CaO, SiO2 and MgO are added as a flux before or during the fuming step so as to obtain a final slag composition with: formula (I) all concentrations being expressed in wt %. The invention also relates to a single-chamber reactor for Zn-fuming equipped with one or more submerged plasma torches as heat and gas sources. [ Fe ] [ SiO 2 ] + [ CaO ] [ SiO 2 ] + [ MgO ] 3 > 3.5 ; 0.1 < [ CaO ] [ SiO 2 ] < 1.

Abstract: A method of restoring the electrical efficiency of channel and pressure pour furnaces includes plunging a fluxing material with a specially designed plunging lance. The plunging lance chamber containing the fluxing material is 24 to 32 inches in length, 3 inches in diameter and has a capacity to hold 5 to 7.5 pounds of flux briquettes. The plunging chamber has holes drilled along the length of the body. The fluxing material contains by weight from 8.0 to 28.7% CaCO3 (calcium carbonate or limestone), from 0 to 18.5% MgCO3 (magnesium carbonate), from 3.6 to 18.0% Al2O3 (alumina) from 1.4 to 7.1% SiO2 (silica), in the form of a complex aluminosilicate, and from 19.4 to 46.4% Na2O (sodium oxide), in the form of soda ash (sodium carbonate). The total level of sodium ranges from 23 to 26% and up to 10% sodium fluoride or sodium chloride may be substituted for soda ash.

Abstract: The high-Cr-containing metal according to the present invention is a chromium-containing metal manufactured in an arc melting furnace, and contains at least 85% Cr, up to 0.005% Al, up to 0.1% Si, and up to 0.002% S. The manufacturing method of this high-Cr-containing metal comprises the steps of reducing chromium oxides heated and melted in the arc melting furnace with Si, obtaining a molten metal containing at least 85% Cr, then, discharging slag generated in this Si reduction from the arc melting furnace, adding a basic flux into the arc melting furnace after discharging slag, melting the basic flux by electric arc, refining the molten metal by contacting the slag generated through melting of the basic flux with the molten metal, and then, tapping the molten metal from the arc melting furnace and cast.

Abstract: A process for producing a high-cleanliness steel is provided which can produce, without relying upon a high-cost remelting process, steel products having cleanliness high enough to satisfy requirements for properties of mechanical parts used under severer environmental conditions. The production process comprises the steps of: transferring a molten steel produced in an arc melting furnace or a converter to a ladle furnace to refine the molten steel; subjecting the molten steel to circulation-type degassing; and casting the molten steel into an ingot, wherein, in transferring the molten steel to the ladle furnace, a deoxidizer including aluminum and silicon, is added to previously deoxidize the molten steel, that is, to perform tapping deoxidation before refining in the ladle refining furnace.

Abstract: A process for producing stainless steels, particularly special steels containing chromium and chromium-nickel, in a smelting arrangement having at least two vessels, for supplying a steel foundry. A charge having mostly iron-containing raw scrap materials and partially carbon-containing alloy carriers is melted in a first vessel. At a temperature of 1460° C., the melt is decarburized by the injection of oxygen so as to reduce the carbon content to less than 0.3%. The melt is heated to a tapping temperature of between 1620° C. to 1720° C. and the carbon content is subsequently reduced to 0.1%. A second charge is melted in a second vessel simultaneously with the decarburizing of the first charge in the first vessel.

Abstract: Disclosed is a process and apparatus for generating high-silicon foundry pig iron. In the process: a) silicon oxides and iron-carbon metals are charged in a shaft furnace; b) the charge is kept under a highly reducing atmosphere; c) the material column is guided annularly at least in the vicinity of the vessel bottom and d) exposed to the radiation heat of a heat source located in the free space in the outlet region of the annular material column above the furnace base. The furnace has a centrally arranged electrode, which projects into the furnace vessel and is guided up to the vicinity of the base, and a counterelectrode arranged in the base of the furnace vessel. The electrode projecting into the vessel is enclosed by a coaxially guided sleeve whose outer diameter “d” is in a ratio to the inner diameter “D” of the furnace vessel such that d;D is about 1:4.