Abstract: A process is divulged for recovering metals from a metal-bearing material containing, in oxidized form, more than 1% of Co, a total of Co and Ni of more than 15%, and more than 1% Mg, comprising smelting said metal-bearing material in a bath furnace together with slag formers, thereby producing an alloy phase with more than 80% of the Co, and less than 1% of the Mg, and a slag phase, by applying reducing smelting conditions, and by selecting CaO, SiO2, and Al2O3 as slag formers, in amounts to obtain a final slag composition according to the ratio's 0.25<SiO2/Al2O3<2.5, 0.5<SiO2/CaO<2.5, and MgO>10%; and separating the alloy phase from the slag phase. This process ensures quantitative recovery of Co in an alloy phase along with other metals such as Ni, while collecting Mg into a slag.

Abstract: A reduction furnace includes a pellet material supplying device forming on a grate an ignition carbon material layer having a predetermined height; an ignition device; and an exhaust gas circulation device supplying an oxygen-containing gas comprising circulated exhaust gas mixed with air, to a packed bed of the pellets heated by a combustion heat of the ignition carbon material layer. A partially-reduced iron is produced by thermally reducing the pellets through a combustion region for the ignition carbon material layer and a heating region, the combustion region formed upstream in a travelling direction of the grate by supplying a gas having a high oxygen concentration, the heating region formed downstream of the combustion region by supplying a gas having a low oxygen concentration.

Abstract: A process and an installation for reducing particulate material containing iron oxide are shown, wherein the material containing iron oxide is at least partially reduced with reducing gas in a reducing zone and the waste gas produced during the reduction is drawn off and subsequently subjected to CO2 cleaning in a CO2 separating device (1), in which a tail gas containing CO2 is separated. The tail gas is subjected to combustion and subsequent dewatering in a dewatering device (5), the substitute gas thereby formed being used as a substitute for inert gas.

Abstract: Combined microwave heating and plasma/electric arc heating is utilized in several processes and apparatus which involve co-production of pig iron and high quality syngas, biomass to liquid fuel production, coal to liquid fuel production, co-gasification of biomass and coal, municipal solid waste treatment, waste-to-energy (agriculture waste, ASR and PEF), EAF dust and BOF sludge treatment to recover zinc and iron, hazardous bottom ash vitrification, and bromine, chlorine and sulfur removal/recycling.

Abstract: A method for producing liquid ferroalloy by direct processing of manganese and chromium bearing iron compounds, by the steps: of mixing carbonaceous reductant, fluxing agent, and a binder with materials such as iron sands, metallic oxides, manganese-iron ore concentrates and/or chromium-iron ore concentrates and silica sands, to form a mixture; forming agglomerates from the mixture; feeding the agglomerates to a melting furnace with other materials; melting the feed materials at a temperature of from 1500 to 1760° C. and forming a slag and hot metal; removing the slag; tapping the hot metal as liquid ferroalloy, and utilizing the off-gases from the melting furnace as combustion fuel to drive a turbine and to generate electricity.

Abstract: The invention refers to metallurgy, in particular to making low (LH) and specified (SH) hardenability steels in electric arc, induction furnaces or oxygen converters. A metallurgical unit is loaded with metal charge consisting of iron carbon alloy, scrap with a specified content of manganese, silicon, chrome, nickel and copper, providing for the final content of each of them of not more than 0.

Abstract: A reduction furnace includes a pellet material supplying device forming on a grate an ignition carbon material layer having a predetermined height; an ignition device; and an exhaust gas circulation device supplying an oxygen-containing gas comprising circulated exhaust gas mixed with air, to a packed bed of the pellets heated by a combustion heat of the ignition carbon material layer. A partially-reduced iron is produced by thermally reducing the pellets through a combustion region for the ignition carbon material layer and a heating region, the combustion region formed upstream in a travelling direction of the grate by supplying a gas having a high oxygen concentration, the heating region formed downstream of the combustion region by supplying a gas having a low oxygen concentration.

Abstract: A process for producing a molten steel (G) is disclosed in which particulate metallic iron can be more efficiently melted. The process includes the step of melting, in an electric arc furnace (2), all charge for iron which comprises: particulate metallic iron (A) produced by a method including a step in which a feed material comprising a carbonaceous reducing material and an iron oxide-containing substance is heated in a rotary hearth furnace (1) as a reducing/melting furnace and the iron oxide contained in the feed material is thereby reduced in the solid state to yield metallic iron and a step in which the resultant metallic iron is heated to a higher temperature to melt the metallic iron and the molten iron is aggregated while separating the iron from the slag (B); and scraps (D) which are another feed material for iron. The process is characterized in that the content of carbon in the particulate metallic iron (A) is regulated to 1.0-4.

Abstract: A method for treating spheroidal graphite iron includes the step: pouring molten spheroidal graphite iron into a pouring electrical furnace (1); covering the molten spheroidal graphite iron (5) with alkali slag (6) which is melted at high temperature and rich in alkali earth metal ion, rare earth metal ion, or mixture of them; connecting the molten spheroidal graphite iron (5) with the negative pole of the direct current source by one pole (7); connecting the alkali slag (6) with the positive pole of the direct current source by another pole (4), treating the molten spheroidal graphite iron (5) with the alkali slag (6) which is used as electrolyte. The method can prevent the spheroidized fading velocity of the spheroidal graphite iron. The pouring electrical furnace can be used for treating the molten spheroidal graphite iron.

Abstract: A method for treating spheroidal graphite iron includes the step: pouring molten spheroidal graphite iron into a pouring electrical furnace (1); covering the molten spheroidal graphite iron (5) with alkali slag (6) which is melted at high temperature and rich in alkali earth metal ion, rare earth metal ion, or mixture of them; connecting the molten spheroidal graphite iron (5) with the negative pole of the direct current source by one pole (7); connecting the alkali slag (6) with the positive pole of the direct current source by another pole (4), treating the molten spheroidal graphite iron (5) with the alkali slag (6) which is used as electrolyte. The method can prevent the spheroidized fading velocity of the spheroidal graphite iron. The pouring electrical furnace can be used for treating the molten spheroidal graphite iron.

Abstract: A Soederberg electrode with low PAH emission that can be used in electro-thermal processes for the production of metal materials, preferably ferro-alloys, which can be obtained from an electrode paste with a base of a carbonaceous material, fine graphite, carbohydrates and water and/or PEG.

Abstract: In order to allow a significant reduction of the steel production cost when producing stainless steel with the alloying elements chromium and nickel, according to the invention, it is proposed to perform the intermediate production of ferrochrimium and ferronickel in two separate direct reduction processes based on low-cost chromium ore and nickel ore in two SAF (3, 4) arranged in parallel on the primary side of a processing converter (6).

Abstract: A process for melting scrap metal for producing steel which includes the steps of combining a quantity of scrap metal and scrap rubber in an electric arc furnace. Energy is then applied to the quantity of steel and scrap rubber in the furnace to start the combustion of the scrap rubber to add additional heat for melting the scrap metal containing steel.

Abstract: A method for producing a ferro-alloy in an electric arc furnace is disclosed. The method comprises the steps of removing steel from a carbon-containing organic material, and charging the furnace with the carbon-containing organic material product.

Abstract: Efficient coordination of processing (by desulphurizing) and moving hot metal from a direct smelter, producing hot metal on a continuous basis, to an electric arc furnace or furnaces, operating on a batch basis, is disclosed. The invention includes the use of hot metal storage devices, such as ladles, that are large enough to supply hot metal for a small number, preferably two or three, of electric arc furnace batch operations.

Abstract: During the production of stainless steel, a slag is formed during the melting of the solid material in the electric arc furnace, the slag having a high degree of metal oxides, particularly chromium oxide. The chromium concentration often reaches values of more than 30%. Currently, such slags cannot be reduced to a desired degree due to their composition. In order to minimize the resulting high loss of recyclable material, the invention provides to charge the electric arc furnace with pellets, or briquettes (8), which are made of a defined mixture of an iron carrier as the ballast material, carbon, or carbon and silicon, as the reducing agent, and a binder, wherein they react beneath the slag layer (7) in the steel melt (6) with the metal oxides of the slag (7), particularly with the chromium oxide present, in a floating, chemical, and reducing manner. The reaction gases (12) produced in the process, which are mainly made of carbon monoxide, advantageously support a foaming of the slag (7).

Abstract: Disclosed are a method and an installation for producing steel products (1) having an optimum surface quality, especially extremely low carbon contents (UCL steel or IF steel), nitrogen contents, total oxygen contents, high-strength or stainless steel qualities.

Abstract: A method of producing steel (1) with a high manganese and low carbon content on the basis of liquid pig iron (2) or liquid steel (3) and slag-forming constituents (4) with the object of preventing existing drawbacks of process route in vessels other than, e.g., electrical arc furnaces (18). With steel produced with a high manganese and low carbon content, in a process, the carbon component is reduced to about 0.7-0.8% by a combined blowing of oxygen (7) through top lances (8) and underbath nozzles (9) after feeding of liquid ferro-manganese (50 and liquid steel (3a) in a FeMn-refining converter (6a), wherein a component of a cold end product from premelt is added as cooling means (10), and wherein the carbon component is reduced to about 0.05-0.1% C by a continuous blowing of oxygen (7) through the underbath nozzles.

Abstract: A method for manufacturing molten iron comprises charging a carbonaceous material, a flux, and solid reduced iron obtained by thermally reducing carbon composite iron oxide agglomerates into an arc melting furnace and melting the solid reduced iron using arc heating in the melting furnace while an inert gas is blown into a molten iron layer from a bottom blowing tuyere on a bottom of the melting furnace, wherein: a carbonaceous material suspending slag layer is formed in an upper portion of a slag layer formed on the molten iron layer when the solid reduced iron is melted into the molten iron; a carbonaceous material coating layer having the carbonaceous material is formed on the carbonaceous material suspending slag layer; and the molten iron and the slag stored in the melting furnace are tapped from a tap hole formed in a lower portion of a furnace wall of the melting furnace.

Abstract: To produce metallic iron from iron ore, a composition comprising a mass of material formed from a mixture of iron ore particles and particles of a reductant that is either a biomass material in particulate form or a plastic resinous material in particulate form is used. The reductant can also be a mixture of biomass material and resin in any proportions. The mass of material comprises at least one body having a shape adapted for smelting such as pellets, briquettes, pieces or lumps. The pellets have sufficient cohesion to maintain the shape into which they have been formed.

Abstract: In a process for utilizing slag containing oxidic iron particles, adding a reducing agent and reducing oxidic iron particles of the slag are charging the slag into a reactor vessel onto a residual iron metal containing dissolved carbon, slowly and continuously over an extended period of time, electric heating the slag and the iron melt over an extended period of time, injecting a carbon-containing reducing agent with inert gas over an extended period of time by a lance into a region close to the boundary surface between the slag and the iron melt or directly into the iron melt, dissolving the carbon of the reducing agent in the iron melt and reducing oxidic iron particles of the slag with metallic iron and CO being formed, over an extended period of time, forming a foamed slag by the resulting CO over an extended period of time, introducing an oxygen-containing gas or oxygen into the foamed slag and postcombustion of CO to CO2 over an extended period of time, bottom flushing the reactor vessel with inert gas

Abstract: Methods of enhancing the segregation roast through the use of microwave radiation and chloride ions are disclosed. The processes provide means of recovering metals trapped in ores and slags by reaction of these materials with carbon, chloride and water using microwave radiation as the primary energy source. The metals may be present in starting materials such as metallic sulfides, slags, metallic oxides such as laterites, magnetites, iron oxides, silicates and carbonates. The metals are reduced and can be recovered by separation from the gangue. Water, carbon and chloride can be recycled to the reaction to reduce costs.

Abstract: A method of operating a channel induction furnace so as to receive electric arc furnace (EAF) dust, basic oxygen furnace (BOF) sludge/dust and/or other iron and volatile metals containing materials as a feed stream on a batch, continuous or semi-continuous basis together with a iron-containing material feed, and therefrom produce an iron-containing hot metal or pig iron product while recovering iron value from the feed materials and recovering volatile metal components contained in the feed materials.

Abstract: A process for making an article with ballistic protective effect and an article obtainable thereby, as well as a method of providing an object with ballistic protection provided by a corresponding material. The alloys used for making the article comprise the elements C, Si, Mn, Cr, Ni, Mo and V within certain concentration ranges and contain a limited amount of impurities. This abstract is neither intended to define the invention disclosed in this specification nor intended to limit the scope of the invention in any way.

Abstract: The invention relates to a method for producing stainless steels, in particular steels containing chromium and chromium-nickel. The method is carried out in a melting device containing a metallurgical vessel, or in a melting device (1) containing at least two vessels (2, 3) for supplying a steel-casting installation, an electric arc furnace process (1) and an air-refining process taking place alternately in the two vessels (2, 3). To improve the efficiency of a method of this type, the aim of the invention is to carry out a reversible treatment of unreduced converter slag in the electric-arc furnace mode. To achieve this, in the first treatment stage, the slag (19) with a high chromium content is melted together with the added charge, the slag is then reduced during the melting process with the silicon and carbon under favorable thermodynamic conditions of the arc, once the slag has reached a minimum temperature of 1,490° C. and the slag is subsequently removed.

Abstract: The invention is a method and apparatus for producing beneficiated titanium oxides using a modified rotary hearth furnace, that is a finisher-hearth-melter (FHM) furnace. In the method the refractory surface of the hearth is coated with carbonaceous hearth conditioners and refractory compounds, where onto said hearth is charged with pre-reduced agglomerates. The pre-reduced agglomerates is leveled, then heated until molten, and then reacted with the carbon and reducing gas burner gases until any residual iron oxide is converted to iron having a low sulfur content. Fluid slag and molted iron forms melted agglomerates. The fluid slag is rich in titanium. The melted agglomerates are cooled, and then the melted agglomerates and the hearth conditioners, including the refractory compounds, are discharged onto a screen, which separate the melted agglomerates from the hearth conditioner.

Abstract: Heat-treated products discharged from a discharge port of a movable hearth type heat treatment furnace, for example a rotary hearth type reduction furnace are discharged to a sorting means, the heat-treated products that foreign substances have been removed, are discharged through a seal leg into which anti-reoxidation gas is blown from a gas blowing nozzle, to a receiving recess of a receiving pan provided within a case having a hopper attached thereto which is a feeding means, and then a scraper is swung to discharge the heat-treated products deposited on the top surface of the receiving recess from the longitudinal ends of the receiving pan and simultaneously to quantitatively feed it to a molten iron-manufacturing furnace 8, which is a downstream side facility, from the bottom side discharge port of the casing having a hopper attached thereto, and in addition, dust removal/cooling means for produced gas of the molten iron-manufacturing furnace and means for regulating the amount of produced gas are provid

Abstract: A method for producing molten metal by the reduction and melting of raw materials in a submerged arc type electric furnace includes at least one electrode, where substantial amounts of slag are generated so that the electric furnace contains a bath of molten metal covered with a thick layer of molten slag having a mass per unit area of at least 1000 kg/m2. The thick layer of molten slag is made to foam locally around the at least one electrode so as to create around the electrode a local layer of foaming slag in which the density of the slag is at least 50 per cent lower than in the rest of the electric furnace.

Abstract: The present invention provides methods for: producing high-purity ferroboron by using inexpensive mass-produced steel as a base iron; and producing a mother alloy for an iron-base amorphous alloy and an iron-base amorphous alloy, the alloys having excellent properties, by using the ferroboron thus produced as a raw material. The methods include: a method for producing high-purity ferroboron by using mass-produced steel obtained through a converter, an electric furnace or the like and having an Al content of 0.03 mass % or less as a base iron; a method for producing a mother alloy by adjusting the chemical composition thereof by adding a diluent base iron and auxiliary materials to the produced ferroboron; and a method for producing an iron-base amorphous alloy by preferably using mass-produced steel obtained through a converter or an electric furnace and having an Al content of 0.

Abstract: The invention concerns an iron powder characterised by spherical form and a porous structure throughout. The powder particles have an average particle diameter between 10 and 300 &mgr;m, a specific surface area of at least 100 m2/kg, a flowability of at least 35 s/50 g, a reactivity of less than 5 minutes and an apparent density lower than about 4 g/cm3. The iron powder is prepared by subjecting a dry powder of essentially spherical iron-containing agglomerates to a heat treatment in a reducing atmosphere at a temperature and time sufficient for obtaining particles essentially consisting of metallic iron and having a porous structure throughout. The obtained particles may then be subjected to sintering at a time and temperature sufficient for obtaining the required strength.

Abstract: This invention relates to a method for operation of a moving hearth furnace in conjunction with an electric melter for production of high purity iron product having a range of silicon and manganese, with low sulfur and phosphorus content. The method includes producing high purity iron product and a range of carbon content product from iron oxide and carbon bearing agglomerates, including the steps of providing a furnace for direct reduction of iron oxide and carbon bearing agglomerates, pre-reducing iron and carbon bearing agglomerates in a furnace having a moving hearth surface, producing intermediate carbon-containing metallized iron. An electric melter furnace is utilized for receiving intermediate carbon-containing metallized iron from the pre-reducing step, which is fed directly and continuously into a central interior area of the electric melter, with heating of the carbon-containing metallized iron in the electric melter under elevated temperatures of about 1300° C. to about 1700° C.

Abstract: A method capable of suppressing damages to furnace wall refractories in a melting furnace and making the working life of them longer and a technique capable of obtaining a molten iron with homogenized composition while keeping a high productivity upon arc heating a pre-reducing iron in a melting furnace to obtain a molten iron, the method comprising supplying a pre-reducing iron to a stationary non-tilting type melting furnace and melting the iron by an arc heating mainly composed of radiation heating, the melting being performed while keeping a refractory wearing index RF represented by the following equation at 400 MWV/m2 or less.

Abstract: The direct reduced iron (DRI) which for at least 80 wt-% has a grain size of not more than 3 mm is melted in an electric arc furnace. The furnace contains a bath of liquid iron. During the operation of the furnace a foamy slag layer is formed on the bath and the DRI falls by gravity through at least one movable lance into the foamy slag layer on the iron bath. Preferably, the distance of the aperture of the lance to the iron bath is kept practically constant.

Abstract: A process comprising: charging a raw material compacting substance containing a carbonaceous reducing agent and an iron oxide contained substance into a moving hearth type furnace; reducing the raw material compacting substance to a reducing ratio 30 to 80% within the reducing furnace to thereby form a shell formed of metal iron or forming a state that a shell formed of metal iron or metal iron are stretched around in a network fashion and a carbonaceous reducing agent remains in a clearance therebetween; agglomerating produced slag containing FeO therein; charging the compacting substance reduced into a melting furnace in a state maintaining a high temperature, and carrying out final reducing and melting to obtain molten meal iron.

Abstract: Disclosed is a method for steel making which includes charging a direct reduction reactor (DRR) with iron ore from a charging system. The iron ore is reduced to hot direct reduced iron (DRI) in the DRR and discharged to rotary kiln(s). The rotary kiln(s) does not process the DRI, but transports the hot DRI to one or more electric arc furnaces (EAF). Top gas (i.e., spent reducing gas) is drawn off of a top section of the DRR. A portion of the top gas is used to pressurize the rotary kiln to prevent air from entering the rotary kiln. Another portion of the top gas flows to a pressure swing adsorber or a vacuum pressure swing adsorber (PSA/VPSA) for CO2 and H2O removal. A cool reducing gas exits the PSA/VPSA. A plasma torch burns natural gas and oxygen to form a hot reducing gas. The hot reducing gas is mixed with the cool reducing gas to form a final reducing gas. The final reducing gas is delivered to the DRR. Also disclosed is a mini-mill to perform the method of steel making.

Abstract: A method for producing high-purity niobium involves refining crude niobium in an electrolyte comprising a melt of salts containing a complex niobium and potassium fluoride and an equimolar mixture of alkaline metal chlorides, the electrolyte further containing sodium fluoride in the amount of from 5 to 15 wt %, and subjecting the obtained cathode deposit to electron-beam melting in a vacuum free of oil vapors under a residual gas pressure of from 5*10−5 to 5*10−7 mm Hg, a melting rate of from 0.7 to 2 mm/min and a leakage into a melting chamber from 0.05 to 0.005 l·&mgr;m/s to produce an ingot of niobium. The method produces high-purity niobium having the total amount of impurities within the range of from 0.002 to 0.007 wt % which satisfies the requirements imposed on the materials used in microwave technology and microelectronics, with reduced losses of niobium in both of the refining stages and increased yield of high-purity niobium.

Abstract: The invention relates to a process for producing directly reduced iron, liquid pig iron and steel, in which charge materials, which are formed from iron ore, preferably in lump and/or pellet form, and, if appropriate, additions, are reduced directly, in a first reduction zone, to form iron sponge, the iron sponge is smelted in a melter gasifier zone supplied with carbon carriers and oxygen-containing gas, to form liquid pig iron, and a reduction gas is generated, which gas, after off-gas cleaning, is introduced into the first reduction zone, where it is converted and drawn off as top gas, and in which process the top gas is subjected to off-gas cleaning, if appropriate is fed to a further reduction zone for direct reduction of iron ore to form iron sponge and, following reaction with the iron ore, is drawn off as export gas and is subjected to off-gas cleaning, and in which process the liquid pig iron and, if appropriate, the iron sponge from the further reduction zone are fed to a steelmaking process, in par

Abstract: For effectively reprocessing iron-containing residual smelting plant materials (1 to 3), in which iron may be present both in metallic form and in oxidic form, with lowest possible energy expenditure, the residual smelting plant materials (1 to 3) are processed into agglomerates (8,11), the agglomerates (8,11) are charged into an electric arc furnace (10), melted there and reduced, and the resultant melt is refined (FIG. 1).

Abstract: To be able to produce metal melts using any metal carriers incurring in metallurgical practice as the charging materials, namely in the most diverse quantitative compositions, a plant for producing metal melts is provided with the following characteristic features:

Abstract: Molten iron is prepared by (1) providing iron oxide and a carbonaceous reducing agent, (2) preparing a shaped product from the carbonaceous reducing agent and the iron oxide, (3) preparing solid reduced iron from the shaped product, wherein the solid reduced iron has a metallization of at least 60%, a specific gravity of at least 1.7, and a carbon content of at least 50% of the theoretical amount required for reducing the iron oxide remaining in the solid reduced iron, and, (4) before substantial cooling occurs, heating the solid reduced iron in an arc heating-type melting furnace at a high temperature. The molten iron can be prepared efficiently from iron ores of relatively low iron content without causing erosion of refractories, at high energy and high reduction efficiencies, and by a simple operation in a simple facility.

Abstract: This invention relates to a method for operation of a rotary hearth furnace in conjunction with an electric melter for production of high purity iron product having a range of silicon and manganese, with low sulfur and phosphorus content. The method includes producing high purity iron product and a range of carbon content product from iron oxide and carbon bearing compacts, including the steps of providing a furnace for direct reduction of iron oxide and carbon bearing compacts, pre-reducing iron and carbon bearing compacts in a furnace having a rotary hearth surface, producing intermediate carbon-containing metallized iron. An electric melter furnace is utilized for receiving intermediate carbon-containing metallized iron from the pre-reducing step, which is fed directly and continuously into a central interior area of the electric melter, with heating of the carbon-containing metallized iron in the electric melter under elevated temperatures of about 1300° C. to about 1700° C.

Abstract: In order to be able to process in an economical manner different iron carriers in varying quantitative compositions, a plant for the production of iron melts (4), in particular steel melts, such as crude steel melts, is equipped with an electric are furnace vessel (1), a refining vessel (3) following upon the furnace vessel (1) via a weir (34) and including a bottom departing from the weir (34) in an at least partially downwardly inclined manner and an oxygen supply means (35, 36) as well as an iron melt tap (41) provided in its end region farther remote from the furnace vessel (1), a decanting vessel (2) following upon the furnace vessel (1) and having a common bottom (18) with the furnace vessel (1), said decanting vessel being provided with a slag tap (43) in its end region farther remote from the furnace vessel (1), a supply means (21) supplying liquid pig iron (20) and opening into the furnace vessel (1), a preheating shaft (5) supplying solid iron carries (7), said preheating shaft being arranged a

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.