Abstract: Methods and apparatus for processing electric arc furnace (“EAF”) dust through a basic oxygen furnace (BOF) to recover iron value from the EAF dust and concentrate zinc from the EAF dust into a material useful as a feed in zinc manufacturing processes. The method results in the reduction of the burden for the regulatory tracking of EAF dust. In addition, the method provides economic savings which result from the reduction of processing fees and the recovery of the value of iron and zinc materials. The apparatus involves the use of existing equipment that is used to recover iron value from other materials generated at steel making facilities, or the installation of new equipment for the purpose of iron reuse.

Abstract: In a method for dechroming and/or denickelifying liquid slags or slag mixtures, in which the liquid slag is charged onto a metal bath, in particular an iron bath, and reduced by feeding carbon or carbon carriers, the carbon feed into the metal bath is effected until a decrease of the Cr and/or Ni oxide contents of the slag to a value of between 0.8 wt.-% and 0.2 wt.-%. As the pregiven Cr oxide content range of the slag is reached, reductants having higher reduction potentials such as, e.g., Al, Ca, Si, Fe—Si or Ca—Si are added in order to lower the Cr and/or Ni oxide contents to below 0.15 wt.-%, preferably below 0.08 wt.-%.

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: A method for cooling hot reduced iron briquettes at low cost without degrading the strength is provided. The method includes a primary cooling step of cooling the hot reduced iron briquettes by steam at a cooling rate of 4.0° C./s or less, a secondary cooling step of cooling the reduced iron briquettes by steam and sprayed water at a cooling rate of 4.0° C./s or less, and a final cooling step of cooling the reduced iron briquettes by sprayed water at a cooling rate of 3.5° C./s or more to a temperature in a final product temperature range. The steam generated by evaporation of sprayed water during the final cooling step is used in the primary and/or secondary cooling step.

Abstract: A base plate of a stainless-steel body material formed by pressing is polished and cleared of burrs by means of an abrasive material that consists mainly of Fe2O3 in a polishing process. The polished base plate is heated to a heat treatment temperature for solid solution in a reducing atmosphere in a heat treatment process. In this heat treatment process, an oxide in the constituents of minute fragments of the abrasive material in the surface of the body material of the base plate is reduced to leave iron, which is dispersed into the body material.

Abstract: The wet granulated iron ore is initially conducted through a drying zone. The ore leaves the drying zone at a temperature of 120-400° C. The ore is then heated in direct contact with hot gas to temperatures of 700-1,100° C. before being delivered to a reduction zone. The ore coming out of the drying zone is fully or partially guided through a separating device so as to separate the ore into fine and coarse grain fractions. The fine-grained ore fraction is conveyed to a granulating device so as to produce an iron ore granulate which is conducted to the drying zone. The coarse-grained ore fraction is heated to temperatures of 700-1,100° C. before it is guide into the reduction zone.

Abstract: A granular thermal insulating material comprising rice hull ash, ceramic clay binder, rice bran and an exfoliating agent, and methods to produce the insulating material.

Abstract: A method of manufacturing reduced iron at high Fe purity efficiently with less intrusion of a slag components using less carbonaceous reducing agent and fuel, comprising charging a compact of the iron oxide containing a carbonaceous reducing agent in a packed bed, reducing the iron oxide to 90% or more while keeping in a solid state by a heat source formed from the lower portion of the furnace and then melting the same, as well as an apparatus for manufacturing the metallic iron, comprising a fire grate disposed in the inside of a packed bed, a compact charged layer on the fire grate, a charging product charging mechanism for supplying the compact and a mechanism for discharging an exhaust gas in the furnace, and a fuel charging mechanism, a fuel combustion space and a molten product stores bath disposed below the fire grate.

Abstract: Arrangement for the reduction of metal-oxide-bearing material, particularly of, iron ore, with a reduction vessel in which the metal-oxide-bearing material is reduced in counterflow with reduction gas and which is provided with an inlet for metal-oxide-bearing material, an inlet for reduction gas, an outlet for off-gas and an outlet for reduced material, a vessel for metal-oxide-bearing material, which is connected with the reduction vessel by means of a line and a first supply line for a sealing gas which serves to seal the reduction vessel against the vessel, which first supply line is provided at the connecting line between the vessel and the reduction vessel, characterized in that at least one additional supply line for a sealing gas is provided at the connecting line, which additional supply line is located between the first supply line and the vessel.

Abstract: A plant for a smelting reduction process for pig iron production using coal and oxygen-containing gas is obtained by converting an existing blast furnace plant by replacing the blast furnace by apparatus including at least one metallurgical vessel for carrying out the smelting reduction process, while retaining at least partly at least one of the following components of the existing blast furnace plant:i) storage bins for iron oreii) storage bins for coke, as storage bins for coaliii) a casting house, for tapping of the metallurgical vesseliv) a gas discharge system for hot gas including dedusting means,v) a cooling water supply system.

Abstract: The present invention relates to a molten steel refining method for refining molten steel, the carbon content of which is not more than 0.1 weight %, by blowing oxygen gas for decarburization at a blowing speed so that a cavity, the depth of which is 150 to 400 mm, can be formed on the surface of molten steel in a straight barrel type vacuum refining apparatus in which a straight barrel type vacuum vessel having no vessel bottom and a ladle are arranged.

Abstract: Synthetic Rutile is prepared from raw ilmenite ore by a method comprising activating ilmenite and subjecting it to a multi-stage countercurrent leaching process in hot hydrochloric acid.

Abstract: In this invention, the smelting reduction operation can be carried out in a high efficiency by charging a carbonaceous material in such an amount that total surface area is not less than 60 m.sup.2 per 1 ton of slag weight. Carbon substance finely particulating through thermal crumbling under a high-temperature atmosphere inside the vessel is used as the carbonaceous material, whereby it is possible to stably conduct the smelting reduction while controlling the scattering of the carbonaceous material, and also the erosion, particularly locally erosion of refractory in the smelting reduction furnace, which was a serious problem in the conventional technique, can considerably be decreased to largely prolong the service life of refractory.

Abstract: The present invention provides a process for efficiently dephosphorizing, dephosphorizing and decarbonizing, or desulfurizing, dephosphorizing and decarbonizing a hot metal in a converter. The amount of flux to be charged and the amount of bottom-blown gas are adjusted so that the bottom-blowing agitation power and the CaO/SiO.sub.2 ratio subsequent to the treatment become at least 0.1 kW/ton and from 0.7 to 2.5, respectively and the hot metal temperature at the treatment end point becomes from 1,200.degree. to 1,450.degree. C. Furthermore, the operation of the process is controlled so that the sum of a T.Fe concentration and a MnO concentration in the slag subsequent to the treatment becomes from 10 to 35% by weight by adjusting the top-blown oxygen feed rate, the flow rate of bottom-blown gas or the top-blowing lance height.

Abstract: According to the present method it is possible to recover metallic aluminium easily and at high recovery rate and low cost from metallic aluminium containing wastes disposed recently in great amounts, said wastes being, for example, aluminium can, aluminium laminated foil, aluminium scraps, aluminium chips, and any other aluminium containing (or accompanying) material. The invention is technically constituted such that the combustible substances of metallic aluminium containing materials are carbonized in a kiln in an atmosphere where oxygen concentration is not higher than 10% by volume or an atmosphere of a carbon dioxide gas, and which kiln is in the temperature range of 300.degree.-600.degree. C., and after cooling, carbonized material and iron content are separated by sieving or magnetically.

Abstract: A refractory-lined high temperature reaction vessel comprises a refractory ring lining constructed of refractory brick, a cooler, and a heat transfer medium disposed between the refractory ring lining and the cooler. The refractory brick comprises magnesia (MgO) and graphite. The heat transfer medium contacts the refractory brick and a cooling surface of the cooler, and is composed of a material that accommodates relative movement between the refractory brick and the cooler. The brick is manufactured such that the graphite has an orientation providing a high thermal conductivity in the lengthwise direction through the brick that is higher than the thermal conductivity in directions perpendicular to the lengthwise direction. The graphite preferably is flake graphite, in the range of about 10 to 20 wt %, and has a size distribution selected to provide maximum brick density.

Abstract: A process for improving the rate of metal production and FeO utilization in a steelmaking process or a process combining iron-making and steelmaking in a single reactor that uses or generates Fe-C metal alloy droplets submerged in an FeO-containing slag. The process involves discharging a charge build-up (electron accumulation) in the slag at the slag-metal alloy interface by means of an electron conductor connected between the metal alloy droplets and a gas at a gas-slag interface, said gas having an oxygen partial pressure of at least about 0.01 atmosphere.

Abstract: A method for recovering useful metal included in slag generated from steel-making process in a convertor. The method comprises the steps of atomizing the slag in water, screening the atomized slag so as to be classified by sizes, dropping the classified slag of similar sizes into a flow of blowing air to sort it into a high-weight group and a low-weight group, and transferring the high-weight group into a furnace to recovering useful metal therefrom. The useful metal can be recovered at a low cost. In addition, since the inventive method does not accompany with the pulverization, polluting factor such as noise and dust is eliminated and thus, the working conditions become more comfortable. Moreover, the inventive method is advantageous in a view of reuse because the low-weight slag is used as useful materials such as short balls, grits, fluxes and aggregates.

Abstract: A process and apparatus for improving metal production in ironmaking and steelmaking processes is disclosed. The use of an inert metallic conductor in the slag-containing crucible and the addition of a transition metal oxide to the slag are the disclosed process improvements.

Abstract: In a method of producing iron and steel, from iron ores largely composed of iron oxides, wherein a direct reduction process is used to produce a solid particulate intermediate product, generally known as sponge iron or Direct Reduced Iron (DRI); pneumatically conveying the DRI in a closed pipe from the reduction reactor of the direct reduction process to the metallurgical furnaces where liquid iron or steel are produced, for example electric arc furnaces, induction furnaces, basic oxygen furnaces, etc. or to a briquetting press to form DRI briquettes, or simply to a silo or storage bin, or in general to a subsequent processing step for said DRI. When the carrier gas is recirculated for reuse, surprisingly air is preferred as the source of such gas, especially for reactive hot DRI. This method has a superior efficiency and productivity and reduces the overall energy consumption relative to currently used DRI steelmaking plants.

Abstract: A garbage incinerator is provided with a system for collecting the grate ash, the boiler ash and the fly ash resulting from the incineration and the collected residue is fed to a melting furnace from which the metal and metal compounds are recovered in the form of a metal-enriched melt and a slag which can be granulated and used in highway construction or the like since it is completely glassy. The metal-enriched melt can also be treated to recover metals therefrom.

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: At least a percentage of iron ore pellets and the like for use in a direct reduction process for the production of sponge iron are coated with a thin porous coating of Portland cement to counteract tendency to aggregate. This is accomplished by method and apparatus that mixes water and cement powder at the point of delivery in a manner such that no pumps are subjected to a wet cement slurry. The slurry is mixed and maintained in suspension by air agitation in a bin and then flowed through a bin discharge pipe and sprayed therefrom onto a passing layer of pellets in a controlled manner by regulated air injection into the discharage pipe.

Abstract: A process for removing non-ferrous metal, such as Cu, Sn, Zn or the like, from solid ferrous scrap, which includes the steps of: admixing solid ferrous scrap containing non-ferrous metal with liquid Al, Mg, and or alloys thereof comprising at least 20 wt. % in total of Al and/or Mg at a temperature of higher than the melting point of the liquid metal and lower than the melting point of Fe; and separating said solid ferrous scrap from said molten metal. The non-ferrous metals in contact with the liquid metal at high temperatures are efficiently dissolved into the liquid metal and transferred from the scrap to the liquid metal. The resulting ferrous scrap is suitable as a Fe source for electric-furnace steelmaking.

Abstract: A method and apparatus for recovering work from a nitrogen stream, wherein the nitrogen is preheated via heat exchange with hot fluid from a chemical process, which process utilizes the oxygen product of the air separation. Preferably at least a part of the expanded nitrogen is utilized to preheat at least one fluid reactant of the chemical process. The chemical process may be gasification or direct reduction of iron oxide, as well as the conversion of natural gas into synthesis gas.

Abstract: A method for compaction of iron bearing materials includes the steps of accumulating iron and steel plant waste materials, including iron bearing fines, hazardous mill waste products, fines, turnings, borings, sludge, dust, mill scale, and the like; and agglomerating such materials by ram briquetting in a ram briquetter.