Abstract: Provided is a smelting method for producing metal by reducing a mixture that includes an oxide ore such as nickel oxide ore, wherein it is possible to improve productivity by raising the metal recovery rate as well as to inexpensively and efficiently produce high-quality metal. The present invention is a smelting method in which: an oxide ore and a carbonaceous reducing agent are mixed; the resulting mixture is heated and subjected to a reduction treatment; and metal and slag, which are reduction products, are obtained, wherein the reduction treatment is carried out in a state in which one or more surface deposits selected from carbonaceous reducing agents, metal oxides, and oxidation inhibitors are deposited on the surface of the mixture.

Abstract: The present disclosure is directed to methods using durable functional materials for processes that include an oxidation step. The durable functional materials are redox active oxygen carrier materials that include a zirconia or yttria-stabilized-zirconia (YSZ) matrix containing a redox-active metal ion(s), such as, but not limited to Fe, Mn, Cu, Co and Cr. In an embodiment, these materials are used in chemical looping processes.

Abstract: An exhaust gas duct apparatus for use in a rotary-hearth furnace for heating a starting material including a carbonaceous reducing material and an iron-oxide containing material to produce reduced iron or granular metallic iron. In an exhaust gas duct for use in the rotary-hearth furnace, a cooling part for cooling an exhaust gas discharged from the rotary-hearth furnace to solidify a metal salt in the exhaust gas, a collision part for allowing the exhaust gas just after being cooled to collide therewith to drop down the metal salt solidified, and a direction change duct for guiding the exhaust gas after being collided, in a direction other than a direction of dropping the metal salt, are arranged in this order in two stages.

Abstract: A grate-kiln pelletizing furnace includes a grate that conveys pelletized material to a rotary kiln, a cooler that cools pelletized material from the rotary kiln, and a gas flow apparatus that directs a stream of gas from the cooler to the rotary kiln to provide preheated process air for pelletized material in the rotary kiln. The gas flow apparatus also directs a stream of gas from the grate to the rotary kiln to vitiate the preheated process air.

Abstract: A hearth furnace for producing direct reduced iron is described. The furnace has first and second combustion chambers, each having a rotating hearth within it to receive iron oxide and reducing agent. A set of rabbles disposed over each of the rotating hearths interacts with the iron oxide and pushes the iron oxide towards an inside or an outside edge of each rotating hearth. The first combustion chamber having an outlet connected to an inlet of the second combustion chamber to receive materials pushed by the rabbles of the first combustion chamber to the first combustion chamber outlet. The furnace further comprising one or more gas transfer channels for transferring reduction gasses and heat between the second and first combustion chambers.

Abstract: A partially-reduced iron producing apparatus includes: a supplying device laying ignition raw-material pellets on an endless-grate; a heating furnace heating the ignition raw-material pellets; another supplying device laying the raw material pellets on the ignition raw-material pellets; and an exhaust gas circulation device supplying an oxygen-containing gas to the raw-material pellets. The oxygen containing gas is made by circulating part of an exhaust gas discharged from the raw-material pellets and mixing it with air. A partially-reduced iron is produced by thermally reducing the raw-material pellets in a bed height direction thereof through separate combustion and heating regions. The combustion region formed on an upstream side in a travelling direction of the endless grate by supplying the oxygen-containing gas having a high oxygen concentration.

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 manufacturing reduced iron agglomerates which comprises introducing starting agglomerates that comprise both an iron oxide-containing material and a carbonaceous reducing agent onto the hearth of a moving-bed heating furnace, and heating the agglomerates to reduce the iron oxide contained in the agglomerates, wherein the iron oxide-containing material contained in the starting agglomerates has a mean particle diameter of 4 to 23 ?m and contains at least 18% of particles having diameters of 10 ?m or less. By the use of such starting agglomerates, the process attains: an improvement in the yield of reduced iron agglomerates having large particle diameters; a reduction in the manufacturing time, said reduction leading to an enhancement in the productivity; and a remarkable reduction in the content of impurities such as sulfur in the reduced-iron agglomerates.

Abstract: A method and system for making metallic iron nodules with reduced CO2 emissions is disclosed. The method includes: assembling a linear hearth furnace having entry and exit portions, at least a conversion zone and a fusion zone, and a moving hearth adapted to move reducible iron bearing material through the furnace on contiguous hearth sections; assembling a shrouded return substantially free of air ingress extending adjacent at least the conversion and fusion zones of the furnace through which hearth sections can move from adjacent the exit portion to adjacent the entry portion of the furnace; transferring the hearth sections from the furnace to the shrouded return adjacent the exit portion; reducing reducible material in the linear hearth furnace to metallic iron nodules; and transporting gases from at least the fusion zone to the shrouded return to heat the hearth sections while in the shrouded return.

Abstract: A method of production of metallic iron nodules comprises assembling a hearth furnace having a moveable hearth comprising refractory material and having a conversion zone and a fusion zone, providing a hearth material layer comprising carbonaceous material on the refractory material, providing a layer of reducible material comprising and iron bearing material arranged in discrete portions over at least a portion of the hearth material layer, delivering oxygen gas into the hearth furnace to a ratio of at least 0.8:1 ponds of oxygen to pounds of iron in the reducible material to heat the conversion zone to a temperature sufficient to at least partially reduce the reducible material and to heat the fusion zone to a temperature sufficient to at least partially reduce the reducible material, and heating the reducible material to form one or more metallic iron nodules and slag.

Abstract: A system of coal gasification and direct ironmaking attains both heat recovery in a coal-based direct ironmaking process and a reduction in equipment investment in a coal gasification process. A waste heat boiler in the system recovers heat of gas exhausted from a coal gasification furnace. A heater in exhaust gas lines of a heat reduction furnace in the coal-based direct ironmaking process superheats the steam generated by and exhausted from the waste heat boiler. A superheated steam line supplies the steam superheated by the heater as an oxidant to the coal gasification furnace.

Abstract: A system of coal gasification and direct ironmaking attains both heat recovery in a coal-based direct ironmaking process and a reduction in equipment investment in a coal gasification process. A waste heat boiler in the system recovers heat of gas exhausted from a coal gasification furnace. A heater in exhaust gas lines of a heat reduction furnace in the coal-based direct ironmaking process superheats the steam generated by and exhausted from the waste heat boiler. A superheated steam line supplies the steam superheated by the heater as an oxidant to the coal gasification furnace.

Abstract: Metallic iron is produced from a composition formed from a mixture of iron ore particles and particles of a reductant made of a biomass material, a coal or coke in a particulate form together with a flux and is processed in a loose, un-agglomerated non-pelletized, non-briquetted form in a reducing furnace to produce metallic iron directly from the ore. An excess of biomass or coal or coke reductant can be used to provide CO and H that can be recovered as a synthetic gas and converted to electrical or other energy. Metallic iron nuggets or slabs can be produced from manganiferous ores or concentrates. Manganese can be caused to enter the nugget or slab or the slag by adjusting the furnace temperature. Titaniferous ores or concentrates can be used to produce metallic iron slabs or nuggets and a titanium-rich slag.

Abstract: Disclosed is a technique for preventing the adhesive of metallic iron and/or wustite (which is a material produced by the heat reduction of iron oxide contained in a powder derived from an agglomerate that comprises, as a raw material, a mixture containing a iron-oxide-containing substance and a carbonaceous reducing material) on a heath of a movable furnace heath type heating furnace without largely changing the design of a facility for the production, in the production of metallic iron by placing the agglomerate on the heath and heating the agglomerate in the heating furnace to reduce iron oxide contained in the agglomerate. A heath-forming material for preventing the cohesive of metallic iron and/or wustite (which is a material produced by the heat reduction of iron oxide contained in the powder derived from the agglomerate) on the heath is charged into the furnace together with the agglomerate.

Abstract: Disclosed is a carbon-material-containing iron oxide briquette composition that, when obtaining direct reduced iron by heating in a moving hearth reduction furnace, does not turn into powder in the furnace leading to an accumulation of powder, and reliably prevents the obtained direct reduced iron from turning into powder during conveyance, decreasing yield. Further disclosed are a method for producing same, and a method for producing direct reduced iron using same. The carbon-material-containing iron oxide briquette composition is characterized by: the solidus temperature that is of an Al2O3-CaO—SiO2 ternary system slag in said briquette composition and that is determined by the amount of contained Al2O3, CaO, and SiO2 being no greater than 1300 DEG C.

Abstract: A method for manufacturing granular metallic iron by reducing a raw material mixture including an iron oxide-containing material and a carbonaceous reducing agent, comprises: a step of charging the raw material mixture onto a hearth of a moving hearth-type thermal reduction furnace; a step of reducing the iron oxide in the raw material mixture by the carbonaceous reducing agent through the application of heat, thereby forming metallic iron, subsequently melting the metallic iron, and coalescing the molten metallic iron to granular metallic iron while separating the molten metallic iron from subgenerated slag; and a step of cooling the metallic iron to solidify; wherein the heat-reducing step includes a step of controlling the flow velocity of atmospheric gas in a predetermined zone of the furnace within a predetermined range. This method makes it possible to manufacture the granular metallic iron of high quality.

Abstract: This invention relates to a waste treatment furnace and method comprising: Generating a molten metal bed, which moves in a forward direction, such as to define a closed circuit in a cyclical and continuous manner, the surface of said bed comprising at least one essentially-slag-free segment. Loading waste onto the aforementioned essentially-slag-free segment, the waste being dragged by the molten metal bed such that it floats in the mentioned forward direction. Retaining the waste on the surface of the molten metal bed as it moves in the mentioned forward direction. Treating the waste under the effect of the constant and continuous heat exchange generated by the movement of the molten metal bed beneath the waste retained thereon.

Abstract: A hearth furnace for producing direct reduced iron is described. The furnace has first and second combustion chambers, each having a rotating hearth within it to receive iron oxide and reducing agent. A set of rabbles disposed over each of the rotating hearths interacts with the iron oxide and pushes the iron oxide towards an inside or an outside edge of each rotating hearth. The first combustion chamber having an outlet connected to an inlet of the second combustion chamber to receive materials pushed by the rabbles of the first combustion chamber to the first combustion chamber outlet. The furnace further comprising one or more gas transfer channels for transferring reduction gasses and heat between the second and first combustion chambers.

Abstract: A method and system for producing metallic iron nuggets may include providing multiple layers of agglomerates, such as briquettes, balls and extrusions, of a reducible mixture of reducing material (such as carbonaceous material) and of a reducible iron bearing material (such as iron oxide) on a hearth material layer (such as carbonaceous material) and providing a coarse overlayer of carbonaceous material over at least some of the agglomerates. Heating the agglomerates of reducible mixture to 1425° C. or 1400° C. or 1375° C. results in formation of an intermediate product of one or more metallic iron nuggets, which may have a sulfur content of less than 0.03%, and slag, which may have less than 5% mass MgO, which may have a ratio of percent by weight sulfur in the slag over percent by weight sulfur in the metallic nuggets of at least about 12 or at least about 15.

Abstract: A method of reduction treatment of metal oxides characterized by using as a material a powder containing metal oxides and containing alkali metals and halogen elements and further, in accordance with need, carbon, mixing the material with water to produce a slurry, then dehydrating this and charging the dehydrated material, mixed with another material in accordance with need, into a rotary hearth type reduction furnace for reduction.

Abstract: A method for producing metallic iron including providing a hearth furnace having an entry end and a discharge end, a moveable hearth, and an exhaust stack positioned toward the entry end of the furnace, providing a carbonaceous hearth layer above the hearth, providing a layer of reducible material comprising reducing material and iron bearing material, delivering a flow of gases into the hearth furnace through burners, gas injection ports, or a combination thereof directing a flow of gases toward the entry end selected from combustible fuel, oxygen and carbon dioxide, oxygen and flue gas, oxygen and air, or a combination thereof to heat the furnace to a temperature sufficient to at least partially reduce the reducible material, increasing the velocity of the flow of gas to greater than 4 feet per second along the furnace, and heating the layer of reducible material to at least partially reduce the reducible material.

Abstract: A process for producing molten iron with a combination of a moving-hearth reducing furnace and an iron bath-type melting furnace that includes charging a bedding carbonaceous material on a hearth of the moving-hearth reducing furnace and placing carbonaceous material-containing agglomerates containing a powdery iron oxide source and a powdery carbonaceous reductant on the bedding carbonaceous material; thermally reducing the carbonaceous material-containing agglomerates while moving the hearth in the moving-hearth reducing furnace to generate solid reduced iron and simultaneously thermally carbonizing the bedding carbonaceous material to generate char; hot-forming the solid reduced iron and the char into agglomerates without substantial cooling; continuously charging the agglomerates into the iron bath-type melting furnace from thereabove; and blowing oxygen-containing gas into the iron bath-type melting furnace to melt the solid reduced iron and to thereby generate molten iron.

Abstract: Provided is a carbon composite briquette which is used as the raw material of a movable hearth furnace for producing reduced iron having a sufficient carbon content and a higher crushing strength, and also provided is a method for producing reduced iron using the carbon composite briquette. The carbon composite briquette for producing reduced iron has a total SiO2+Al2O3+CaO+MgO content that is between 7 and 15 mass %; an MgO content that is between 0.1 and 6 mass %; an Al2O3/SiO2 mass ratio that is between 0.34 and 0.52; a CaO/SiO2 mass ratio that is between 0.25 and 2.0; and a C content such that between 1 and 9 mass % of C is retained in the resulting reduced iron.

Abstract: An object of the present invention is to provide a method for reducing a chromium-containing material at a high chromium reduction degree. In the method of the present invention, a mixture of a feedstock containing chromium oxide and a carbonaceous reductant is heated and reduced by radiation heating in a moving hearth furnace. The average rate of raising the temperature of the mixture in the reduction is preferably 13.96° C./s or higher in the period from the initiation of the radiation heating of the mixture until the mixture reaches 1,114° C.

Abstract: An object of the present invention is to provide a method for producing granulated metallic iron superior in rust resistance. Another object of the present invention is to provide a method for producing such granulated metallic iron. In the method, the granulated metallic iron is produced by agglomerating a material mixture including an iron-oxide-containing material and a carbonaceous reducing agent; charging and heating the agglomerated material mixture in a moving hearth-type reducing furnace to reduce the iron oxide in the material mixture with the carbonaceous reducing agent to obtain hot granulated metallic iron; and cooling the hot granulated metallic iron, wherein the hot granulated metallic iron is cooled while its relative position is changed; and an oxide coating is formed on the surface of the hot granulated metallic iron by bringing moisture into contact with almost the entire surface of the hot granulated metallic iron.

Abstract: A producing method of direct reduced iron includes the steps of: drying an oxidized iron raw material selected from a group including iron ore and iron-making dust generated in an iron-making process to have a predetermined moisture content; mixing the oxidized iron raw material subjected to the drying step and a reducing material having a predetermined moisture content to obtain a mixture; pulverizing the mixture obtained in the mixing step for 80% minus-sieve to have a particle diameter of 70 ?m to 500 ?m; kneading the mixture after the moisture content of the mixture subjected to the pulverizing step is adjusted; agglomerating the mixture subjected to the kneading step to be agglomerate; and reducing the agglomerate obtained in the agglomerating step by a rotary hearth furnace to generate direct reduced iron.

Abstract: A hearth furnace 10 for producing metallic iron material has a furnace housing 11 with a drying/preheat zone 12 capable of providing a drying/preheat atmosphere for reducible material, a conversion zone 13 capable of providing a reducing atmosphere for reducible material, a fusion zone 14 capable of providing an atmosphere to at least partially reduced metallic iron material, and optionally a cooling zone 15 capable of providing a cooling atmosphere for reduced material containing metallic iron material. A hearth 20 is movable within the furnace housing 11 in a direction through the drying/preheat zone 12, then the conversion zone 13, then the fusion zone 14, and then the cooling zone 15.

Abstract: Method and system for producing metallic nuggets includes providing reducible mixture (e.g., reducible micro-agglomerates; reducing material and reducible iron bearing material; reducible mixture including additives such as a fluxing agent; compacts, etc.) on at least a portion of a hearth material layer. In one embodiment, a plurality of channel openings extend at least partially through a layer of the reducible mixture to define a plurality of nugget forming reducible material regions. Such channel openings may be at least partially filled with nugget separation fill material (e.g., carbonaceous material). Thermally treating the layer of reducible mixture results in formation of one or more metallic iron nuggets. In other embodiments, various compositions of the reducible mixture and the formation of the reducible mixture provide one or more beneficial characteristics.

Abstract: A high purity of molten iron is produced efficiently at a higher productivity, by feeding a raw material mixture containing a carbonaceous reducing agent, an iron oxide-containing material and a CaO-containing material onto a hearth of a moving-hearth reducing furnace, heat-reducing the raw material mixture in the reducing furnace, and melting it in a melting furnace melting, wherein a blending amount of the CaO-containing material in the raw material mixture is adjusted in such a manner that another feeding of the CaO-containing material into the melting furnace makes a basicity of a slag generated in the melting furnace 1.1 or more an feeding amount of the CaO-containing material becomes 40 kg or less per ton of the molten iron obtained in the melting furnace.

Abstract: A multiple moving hearth furnace (10) having a furnace housing (11) with at least two moving hearths (20) positioned laterally within the furnace housing, the hearths moving in opposite directions and each moving hearth (20) capable of being charged with at least one layer of iron oxide and carbon bearing material at one end, and being capable of discharging reduced material at the other end. A heat insulating partition (92) is positioned between adjacent moving hearths of at least portions of the conversion zones (13), and is capable of communicating gases between the atmospheres of the conversion zones of adjacent moving hearths. A drying/preheat zone (12), a conversion zone (13), and optionally a cooling zone (15) are sequentially positioned along each moving hearth (30) in the furnace housing (11).

Abstract: The present invention provides a method of manufacturing direct reduction iron and a reduction firing apparatus. The apparatus may be a dual-chamber stepping reduction furnace, a single chamber stepping reduction furnace or a single hearth down-draft reduction furnace, wherein the dual-chamber stepping reduction furnace includes a left chamber, a right chamber, a material containing device, a step mechanism, a slag distributing device, a charging device, heating burners, a fume extraction path, a charging device, a material receiving tank having a sealing cap and a slag discharging path.

Abstract: The method includes the steps of: adding a carbonaceous material B and a binder C, and optionally water, to electric furnace dust A generated in a steelmaking electric furnace 1, to form a powdery mixture D having a water content of 0.5 to 3 mass %; compacting the powdery mixture D into a raw briquette E; and charging the raw briquette without drying into a rotary hearth furnace 5 and thermally reducing the raw briquette to obtain a reduced iron briquette F and a crude zinc oxide G.

Abstract: A hearth furnace 10 for producing metallic iron material has a furnace housing 11 having a drying/preheat zone 12, a conversion zone 13, a fusion zone 14, and optionally a cooling zone 15, the conversion zone 13 is between the drying/preheat zone 12 and the fusion zone 14. A moving hearth 20 is positioned within the furnace housing 11. A hood or separation barrier 30 within at least a portion of the conversion zone 13, fusion zone 14 or both separates the fusion zone 14 into an upper region and a lower region with the lower region adjacent the hearth 20 and the upper region adjacent the lower region and spaced from the hearth 20. An injector introduces a gaseous reductant into the lower region adjacent the hearth 20. A combustion region may be formed above the hood or separation barrier.

Abstract: In a method of producing a reduced iron cast, a cast of a powder which includes total iron of 40% or more and an atomic molar amount of fixed carbon of 0.7 to 1.5 times the atomic molar amount of oxygen compounded with metal oxide reduced in a carbon monoxide atmosphere at 1200° C. is reduced in a rotary hearth furnace. The method includes: producing, in an atmosphere at a maximum temperature of 1200° C. to 1420° C. at a ratio of carbon monoxide to carbon dioxide of 0.3 to 1.2 in the reduced zone, a reduced iron-containing material in which a ratio of metal iron is 50 mass % or more and a ratio of carbon is 5 mass % or less; and compression-molding the reduced iron-containing material at a temperature of 500° C. to 800° C. by a roller-type mold.

Abstract: The present invention provides a method for efficiently manufacturing a titanium oxide-containing slag from a material including titanium oxide and iron oxide, wherein a reduction of titanium dioxide is suppressed and the electric power consumption is minimized. The method includes the steps of: heating a raw material mixture including titanium oxide, iron oxide, and a carbonaceous reductant, or the raw material mixture further including a calcium oxide source, in a reducing furnace; reducing the iron oxide in the mixture to form reduced iron; feeding the resultant mixture to a heating melting furnace; heating the resultant mixture in the heating melting furnace to melt the reduced iron and separate the reduced iron from a titanium oxide-containing slag; and discharging and recovering the titanium oxide-containing slag out of the furnace.

Abstract: A rotary hearth furnace includes an exhaust gas eductor. The exhaust gas eductor includes a compartment-defining portion and an exhaust duct. The compartment-defining portion is provided on part of a ceiling of the rotary hearth furnace in an exhaust gas discharge region, and an exhaust duct is connected to the compartment-defining portion. The lower surface of the compartment-defining portion lies higher than the lower surface of the other portion of the ceiling. The compartment-defining portion defines a compartment where the exhaust gas stays. The exhaust duct can include a cooling medium injection nozzle. The furnace increases fuel efficiency by completely burning combustible components remaining in exhaust gas generated in the rotary hearth furnace so as to use the combustible components efficiently for the heating and reduction reaction in the rotary hearth furnace, without problems in producing reduced iron.

Abstract: A process for producing molten iron with a combination of a moving-hearth reducing furnace and an iron bath-type melting furnace includes a step of charging a bedding carbonaceous material having an average particle diameter of 1 to 5 mm on a hearth of the moving-hearth reducing furnace and placing carbonaceous material-containing agglomerates containing a powdery iron oxide source and a powdery carbonaceous reductant on the bedding carbonaceous material; a step of thermally reducing the carbonaceous material-containing agglomerates while moving the hearth in the moving-hearth reducing furnace to generate solid reduced iron and simultaneously thermally carbonizing the bedding carbonaceous material to generate char; a step of continuously charging the solid reduced iron and the char into the iron bath-type melting furnace from thereabove without substantial cooling; and a step of blowing oxygen-containing gas into the iron bath-type melting furnace to melt the solid reduced iron and to thereby generate molt

Abstract: A method for producing metallic iron nodules by assembling a shielding entry system to introduce coarse carbonaceous material greater than 6 mesh in to the furnace atmosphere at location(s) where the temperature of the furnace atmosphere adjacent at least partially reduced reducible iron bearing material is between about 2200 and 2650° F. (1200 and 1450° C.), the shielding entry system adapted to inhibit emission of infrared radiation from the furnace atmosphere and seal the furnace atmosphere from exterior atmosphere while introducing coarse carbonaceous material greater than 6 mesh into the furnace to be distributed over the at least partially reduced reducible iron bearing material, and heating the covered at least partially reduced reducible iron bearing material in a fusion atmosphere to assist in fusion and inhibit reoxidation of the reduced material during fusion to assist in fusion and inhibit reoxidation of the reduced material in forming metallic iron nodules.

Abstract: It is an object of the present invention to provide a technique for solving the following problem by properly controlling the flow of gas such as air (oxidizing gas): a problem that the degree of reduction cannot be increased due to the air entering a feedstock-feeding zone or a discharging zone. The technique is a method for producing reduced iron. The method includes a feedstock-feeding step of feeding a feedstock containing a carbonaceous reductant and an iron oxide-containing material into a rotary hearth furnace, a heating/reducing step of heating the feedstock to reduce iron oxide contained in the feedstock into reduced iron, a melting step of melting the reduced iron, a cooling step of cooling the molten reduced iron, and a discharging step of discharging the cooled reduced iron, these steps being performed in that order in the direction that a hearth is moved.

Abstract: A metallurgical process involves providing an ingredient enclosure and placing a plurality of granules of a first material in the ingredient enclosure. The first material contains a first ingredient in a metallurgical process. A metallurgical process furnace having a chamber in which ingredients for the metallurgical process are added is provided and the ingredient enclosure and the first material are added to the chamber. The chamber is heated after the addition of the ingredient enclosure and the first material to the chamber, although it may also be heated prior to such addition. In one form, the granules comprise mill scale and the metallurgical process furnace is a blast furnace.

Abstract: The disclosure relates to improvements of technology for producing metallic iron by thermally reducing an iron source such as iron ore with a carbonaceous reductant such as coke by including efficiently reducing iron oxides into metallic iron at a lower operation temperature while conducting carburization, and efficiently separating the generated metallic iron from slag-forming components such as gangue components contained in raw material ore whereby metallic iron with controlled carbon concentrations can be produced in high yield.

Abstract: The present invention provides a method and facility for preventing crumbling and powderization of green pellets when producing high strength green pellets using a powder feedstock and using the pellets in a rotary hearth reducing furnace and for efficiently reducing the same. It comprises kneading by a kneader 5 a feedstock of a powder of a fine particle size (20 to 80 wt % having size of not more than 10 ?m) including a metal oxide and carbon-bearing powder fed from a feed storage tank 1 and producing green pellets by a pan type pelletizer 7. The green pellets are screened by a pellet screen 9, then dried by a pellet dryer 11 and reduced by firing in a rotary hearth reducing furnace 13. At that time, the green pellets are continuously conveyed to prevent crumbling.

Abstract: A method is provided for producing an agglomerated material that is used for producing metallic iron by heat reduction in a moving hearth-type reducing furnace, wherein the agglomerated material can have a high mechanical strength without increases in the binder content and the moisture content of the material mixture. The method for producing an agglomerated material used for producing metallic iron, wherein the agglomerated material is produced by agglomerating a material mixture containing an iron-oxide-containing material, a carbonaceous reducing agent, a binder, and moisture; drying the material mixture; and charging and heating the material mixture in a moving hearth-type reducing furnace to reduce the iron oxide contained in the material mixture with the carbonaceous reducing agent, wherein a carbohydrate is used as the binder and the material mixture is left to stand prior to the agglomeration.

Abstract: A method of making metallic iron in which a compact, containing iron oxide such as iron ore or the like and a carbonaceous reductant such as coal or the like, is used as material, and the iron oxide is reduced through the application of heat, thereby making metallic iron. In the course of this reduction, a shell composed of metallic iron is generated and grown on the surface of the compact, and slag aggregates inside the shell. This reduction continues until substantially no iron oxide is present within the metallic iron shell. Subsequently, heating is further performed to melt the metallic iron and slag. Molten metallic iron and molten slag are separated one from the other, thereby obtaining metallic iron with a relatively high metallization ratio.

Abstract: A method of reduction treatment of metal oxides characterized by using as a material a powder containing metal oxides and containing alkali metals and halogen elements and further, in accordance with need, carbon, mixing said material with water to produce a slurry, then dehydrating this and charging the dehydrated material, mixed with another material in accordance with need, into a rotary hearth type reduction furnace for reduction.

Abstract: A method for producing metallic iron in which a mixture including a carbonaceous reducing agent and iron oxide is fed onto a hearth of a moving hearth reducing-melting furnace and is then heated so that the iron oxide is reduced and melted. Metallic iron to be obtained is cooled and is then discharged outside the furnace for recovery. Prior to the feed of raw agglomerates, a granular hearth material is bedded on the moving hearth for forming a layered renewable hearth which can be renewed. Part or the entirety of the renewable hearth which was degraded during operation is renewed, and the hearth material for forming a new renewable hearth is fed. The surface of the newly formed hearth is then leveled and mixture is subsequently fed.

Abstract: The present invention provides a method and facility for preventing crumbling and powderization of green pellets when producing high strength green pellets using a powder feedstock and using the pellets in a rotary hearth reducing furnace and for efficiently reducing the same. It comprises kneading by a kneader 5 a feedstock of a powder of a fine particle size (20 to 80 wt % having size of not more than 10 ?m) including a metal oxide and carbon-bearing powder fed from a feed storage tank 1 and producing green pellets by a pan type pelletized 7. The green pellets are screened by a pellet screen 9, then dried by a pellet dryer 11 and reduced by firing in a rotary hearth reducing furnace 13. At that time, the green pellets are continuously conveyed to prevent crumbling.

Abstract: The present invention provides a method capable of producing good hot-briquette iron using high-temperature reduced iron discharged at a high temperature from a reducing furnace such as a rotary hearth furnace. The method includes a temperature control step of cooling the high-temperature reduced iron and controlling the temperature of the reduced iron to an appropriate hot-forming temperature of over 600° C. and 750° C. or less, and a step of producing hot briquette iron by hot-forming the high-temperature reduced iron of the appropriate hot-forming temperature with a briquetting machine.

Abstract: A metallurgical process involves providing an ingredient enclosure and placing a plurality of granules of a first material in the ingredient enclosure. The first material contains a first ingredient in a metallurgical process. A metallurgical process furnace having a chamber in which ingredients for the metallurgical process are added is provided and the ingredient enclosure and the first material are added to the chamber. The chamber is heated after the addition of the ingredient enclosure and the first material to the chamber, although it may also be heated prior to such addition. In one form, the granules comprise mill scale and the metallurgical process furnace is a blast furnace.

Abstract: A hearth material is laid in the form of a layer on the hearth prior to supply of a mixture containing a carbonaceous reducing agent and iron oxides onto a hearth of a reduction melting furnace, thereby forming a renewable hearth capable of being renewed, and the metallic iron is produced while renewing a part or the whole of the renewable hearth, which has deteriorated during operation, with the hearth material.