Abstract: Carbothermic reduction of magnesium oxide at approximately 2200 degrees Kelvin yields a high temperature mixture of magnesium vapors and carbon monoxide gas. Previous processes have sought to cool or alter the mixture to cause the yield of pure magnesium, which is then used in subsequent processes for its reducing properties. The present invention takes advantage of the stability and inertness of carbon monoxide at elevated temperatures enabling the magnesium vapor/carbon monoxide gas mixture from the carbothermic process to be used directly for the production of other metals at high temperatures. For example, Chromium oxide or chloride, manganese oxide or chloride, zinc oxide or chloride or sulfide, and several other metal compounds can be reduced by the magnesium vapor/carbon monoxide gas mixture at temperatures high enough to prevent the gas mixture from back-reacting to magnesium oxide and carbon.

Abstract: The present invention relates to a method of operating a converter, in particular a Peirce-Smith converter or a converter with similar design or mode of operation, and to an apparatus, for instance a plant, for carrying out the method. The method comprises the step of: loading the converter with a starting material comprising said metal, the metal in the starting material being chemically bound at least in part to at least one compound substance, in particular sulphur; maintaining a temperature within the converter interior space, which is above the melting temperature of the starting material; and supplying an oxygen-containing process gas into the converter interior space through injection nozzles arranged in the wall of the converter, the gas supplied through the injection nozzles comprising carbon dioxide, preferably very cold, technically pure carbon dioxide, as well as oxygen gas and/or air.

Abstract: In a method for producing pig iron using iron ore with a high content of zinc, a blast furnace raw material 2 is produced using iron ore with a high content of zinc which contains 0.01 mass % or more of zinc and 50 mass % or more of iron, pig iron is produced by charging the blast furnace raw material 2 into a blast furnace 1 and, at the same time, zinc-containing dust 4 in a blast furnace discharge gas is recovered, and zinc 6 is recovered from the zinc-containing dust 4 using a reduction furnace 5. A mixed raw material into which the zinc-containing dust 4, a carbonaceous solid reducing material and a slag-making material are mixed is preferably charged on a movable hearth, and the mixed raw material is preferably reduced by supplying heat from an upper portion of the movable hearth so as to recover zinc 6 while producing reduced iron 7.

Abstract: Burner assembly for use in industrial heating and melting applications of material susceptible to oxidation at elevated temperatures is comprised of a flow passage of oxidant surrounded by an annular flow passage of fuel whereby the oxidant is substantially contained inside the fuel layer up to at least 5 oxidant nozzle diameters downstream of the burner outlet in order to minimize contact between the oxidant and the furnace load.

Abstract: The present invention relates to a method of operating a converter, in particular a Peirce-Smith converter or a converter with similar design or mode of operation, and to an apparatus, for instance a plant, for carrying out the method. The method comprises the step of: loading the converter with a starting material comprising said metal, the metal in the starting material being chemically bound at least in part to at least one compound substance, in particular sulphur; maintaining a temperature within the converter interior space, which is above the melting temperature of the starting material; and supplying an oxygen-containing process gas into the converter interior space through injection nozzles arranged in the wall of the converter, the gas supplied through the injection nozzles comprising carbon dioxide, preferably very cold, technically pure carbon dioxide, as well as oxygen gas and/or air.

Abstract: A method for making reduced iron using blast-furnace sludge is provided. The method includes a mixing step of mixing the blast-furnace sludge and an iron-oxide-containing powder to prepare a mixed material, an agglomerating step of agglomerating the mixed material to form agglomerates, a feeding step of feeding the agglomerates onto a continuously moving hearth, and a reducing step of heating the agglomerates to remove zinc and reduce the agglomerates.

Abstract: A carbonaceous material is controlled such that the amount of carbon is from 7 to 60 mass % based on the total amount of iron and Zn in a starting mixture comprising one or more of ducts containing iron oxide and Zn oxide and a binder in an amount to bond the dusts, and water is added to prepare green pellets incorporated with the carbonaceous material. Then, dry pellets prepared by drying the thus prepared green pellets into a reduction furnace, the dry pellets are heated by heat transfer, mainly, radiation such that a temperature elevation rate is from 3 to 13° C./sec within a temperature range from 150 to 900° C. of the pellets, thereby reducing Zn oxide and evaporating Zn, as well as reducing iron oxide to produce reduced iron pellets.

Abstract: A carbonaceous material is controlled such that the amount of carbon is from 7 to 60 mass % based on the total amount of iron and Zn in a starting mixture comprising one or more of ducts containing iron oxide and Zn oxide and a binder in an amount to bond the dusts, and water is added to prepare green pellets incorporated with the carbonaceous material. Then, dry pellets prepared by drying the thus prepared green pellets into a reduction furnace, the dry pellets are heated by heat transfer, mainly, radiation such that a temperature elevation rate is from 3 to 13.degree. C./sec within a temperature range from 150 to 900.degree. C. of the pellets, thereby reducing Zn oxide and evaporating Zn, as well as reducing iron oxide to produce reduced iron pellets.

Abstract: A process of recovering iron values and separating zinc oxides and other contaminants from steel mill waste metal oxides, such as blast furnace dust, BOF dust, mill scale and oily sludges, characterized by iron metallization levels up to 95% or more and zinc oxide removal in excess of 99%, and including the steps of blending the oxides with coke breeze in an amount sufficient to provide a total carbon content of 16% to 22%, the coke breeze having a particle size of 50% or more plus 60 mesh or larger, briquetting the blend to form briquettes having a thickness ranging from 1/2" to 3/4", and firing the briquettes in a rotary hearth furnace to metallize the iron and evolve zinc and other oxide contaminants.

Abstract: A process for recovering iron from iron-bearing materials including steel mill waste and iron-bearing ores. The process includes the steps of providing a mixture of iron-bearing materials having iron oxides therein and carbonaceous material. The mixture is agglomerated to form green compacts. The green compacts are then loaded into a preheated rotary hearth furnace void of compacts to form a layer of compacts no more than about two compacts high. The green compacts are heated for about 5 to 12 minutes at a temperature of between about 2200.degree. F. to 2500.degree. F. to reduce the compacts and evolve undesirable oxides from the compacts. The reduced compacts are then discharged from the rotary hearth furnace whereupon they are soaked to provide additional time for reaction to achieve 99% or more reduction of the iron oxides. The metallized iron compacts may then be cooled or transported hot to a steel making operation.

Abstract: A process for treating iron-bearing material with a carbonaceous material to form a dry mixture, wherein the amount of carbonaceous material added exceeds the stoichiometric amount required to reduce the metal oxide to elemental metal. In one embodiment, the process also includes blending an organic binder with the dry mixture. The dry mixture is agglomerated to bond the dry mixture and form green compacts. The green compacts are loaded into a heated furnace and heated for about 5-12 minutes at a temperature of between about 2100.degree.-2500.degree. F. to reduce the iron oxide containing compacts to compacts containing elemental iron and an excess amount of carbonaceous material wherein the excess amount of carbonaceous material counteracts re-oxidation of the elemental iron. The reduced compacts are then discharged from the furnace.

Abstract: Copper and or nickel sulfide ore concentrates of high intrinsic value are oxygen smelted by introducing such concentrates via feeds (32) into a closed loop extraction circuit in which a molten sulphide carrier composition is forcibly circulated by an R-H unit (14) through lower hearth (10) at which feed of the concentrates takes place, and upper hearth (12) at which controlled oxidation with technically pure oxygen through top lances (4) takes place to oxidize copper sulphide and iron sulphide in the concentrate to iron oxide. Copper is removed via line (42). Slag containing iron oxide is discharged via weir (22) into a secondary circuit in hearths (24 and 28). Carbonaceous reductant added to the slag in (28) reduces the iron oxide in the slag to hot iron product.

Abstract: A process for recovering iron from iron-bearing materials including steel mill waste and iron-bearing ores. The process includes the steps of combining the iron-bearing materials, having metal oxides including iron oxides therein, with carbonaceous material to form a dry mixture. The dry mixture is agglomerated under conditions sufficient to mobilize volatile matter from the carbonaceous material to function as a binder and bond the dry mixture and form green compacts. The green compacts are then loaded into a preheated rotary hearth furnace void of compacts to form a layer of compacts no more than about two compacts high. The green compacts are heated for about 5 to 12 minutes at a temperature of between about 2150.degree. F. to 2350.degree. F. to reduce the compacts and evolve undesirable oxides from the compacts. The reduced compacts are then discharged from the rotary hearth furnace whereupon they are soaked to provide additional time for reaction to achieve 99% or more reduction of the iron oxides.

Abstract: In situ formation of metal-ceramic oxide microstructures is carried out on a starting oxide phase containing at least a most noble metallic component (e.g., iron) and a least noble metallic component (e.g. manganese) and subjecting the starting oxide phase to a temperature and oxygen partial pressure and for a time period to cause reduction of only part of the most noble metallic component to elemental metal.

Abstract: A method and apparatus for treating zinc concentrates in order to recover zinc. The method includes an oxidizing and smelting stage (10) and, subsequent to the smelting stage, a fuming stage (20) in which the zinc-oxide-containing slag formed in the smelting stage is so reduced as to remove the metallic zinc with the exhaust gases (28). Part of the reduced slag is discharged during the fuming stage, another part (32) is recirculated to the smelting stage. In accordance with a preferable method, the slag is reduced in two successive fuming stages (20, 40). In an apparatus according to the invention, the slag circulation between the fuming and smelting stages is facilitated by overflows arranged in the partition walls (19) between the various stages.

Abstract: The invented pellet reclamation process includes forming green pellets of a mixture of steel furnace dust, a carbonaceous material such as coal, charcoal, lignite, petroleum coke, or coke, and an organic binder. The green pellets are fed over a layer of burnt pellets on a rotary hearth furnace which successively conveys the pellets first through a drying and coking zone in which the pellets are dried and any volatile matter driven out of the carbonaceous material. The pellets then travel through a reduction zone where the pellets are subjected to a higher temperature at which the contained iron oxide is reduced and remains within the pellets and the zinc, lead and cadmium oxides are reduced, volatilized, re-oxidized and carried off as oxides in the waste gases. The reduced pellets (DRI) are ultimately carried into a discharge zone where they are discharged from the rotary hearth furnace. An apparatus for performing the process is also disclosed.

Abstract: This invention relates to the metallurgy of iron and particularly to the separation and recovery of metals from electric arc furnace (EAF) dusts. While the invention discloses a process for the separation and recovery applicable to zinc, lead, cadmium and antimony contained in such EAF dusts, the invention is particularly applicable to the separation and recovery of zinc. This invention describes a method for reducing the zinc contained in an EAF dust, volatilizing the metallic zinc so produced from the mass of the dust, and reoxidizing the metallic zinc to zinc oxide along with the simultaneous regeneration of hydrogen which can be recycled to treat additional EAF dust.