Abstract: A method of recovering metallic iron from iron-bearing metallurgical waste in steelmaking comprising steps of providing an iron-bearing metallurgical waste containing more than 55% by weight FeO and FeO equivalent and a particle size of at least 80% less than 10 mesh, mixing the iron-bearing metallurgical waste with a carbonaceous material to form a reducible mixture where the carbonaceous material is between 80 and 110% of the stoichiometric amount needed to reduce the iron-bearing waste to metallic iron, and as needed additions to provide a silica content between 0.8 and 8% by weight and a ratio of CaO/SiO2 between 1.4 and 1.8, forming agglomerates of the reducible mixture over a hearth material layer to protect the hearth, heating the agglomerates to a higher temperature above the melting point of iron to form nodules of metallic iron and slag material from the agglomerates by melting.

Abstract: The present invention is one or more processes for producing separable iron and titanium oxides from an ore comprising titanium oxide and iron oxide, comprising: (a) forming agglomerates comprising carbon-based material and the ore, the quantity of carbon of the agglomerates being at least sufficient for forming a ferrous oxide-containing molten slag, at an elevated temperature; (b) introducing the agglomerates onto a bed of carbon-based material in a moving hearth furnace, wherein the carbon-based materials used for both the agglomerates and the bed have a low sulfur content; (c) heating the agglomerates in the moving hearth furnace to a temperature sufficient for liquefying the agglomerates to produce a liquid comprising ferrous oxide-containing slag; (d) metallizing the ferrous oxide of the slag by reaction of the ferrous oxide and the carbon of the carbon bed at a furnace temperature sufficient for maintaining the slag in a liquid state; (e) solidifying the slag after metallization of the ferrous oxide to

Abstract: A method of producing metallic iron nuggets includes providing a hearth with refractory material, and providing a reducible mixture above at least a portion of the hearth, where the reducible mixture includes reducible iron bearing material, reducing material such that the reducible mixture has a quantity of reducible iron bearing material and between about 65% and about 90% of a stoichiometric amount of reducing material necessary for complete iron reduction of the reducible iron material, between about 1% and 4% by weight manganese oxide, between about 1% and 3% by weight fluorspar, and additives providing a slag basicity ratio of CaO/SiO2 between 1.2 and 1.7. Then the method includes thermally treating the reducible mixture in the presence of other carbonaceous material separate from the reducible mixture forming one or more metallic iron nuggets by melting.

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 mate?al, and heating the reducible material to form one or more metallic iron nodules and slag.

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: A battery of stationary hearth furnaces, and method for using, for producing metallic iron nodules having a furnace having a stationary hearth, an inlet and an outlet; a heating chamber beneath the stationary hearth having heated fluids circulated thereto and heating reducible material on the stationary hearth; passageways circulating fluids, through ports from the furnace housing above the reducible material to the heating chamber beneath; burners and air inlets in the furnace and optionally in at least one passageway and a heating chamber for drying and heating the reducible material, driving off and burning volatile material, and forming metallic iron nodules; a loading device for loading reducible material and optionally hearth material onto the stationary hearth through the inlet; and a discharging device capable of discharging metallic iron nodules and optionally related material from the stationary hearth through the outlet.

Abstract: The disclosure is directed to a process for producing separable iron and titanium oxides from an ore containing titanium oxide and ferric oxide, comprising: (a) forming agglomerates comprising carbon-based materials and the ore, the quantity of carbon of the agglomerates being sufficient for, at an elevated temperature, reducing ferric oxide to ferrous oxide and forming a ferrous oxide-rich molten slag, (b) introducing the agglomerates onto a carbon bed of a moving hearth furnace; (c) heating the agglomerates in the moving hearth furnace to a temperature sufficient for reducing and melting the agglomerates to produce a ferrous oxide-rich molten slag; (d) metallizing the ferrous oxide of the molten slag by reaction of the ferrous oxide and the carbon of the carbon bed at a furnace temperature sufficient for maintaining the slag in a molten state; and (e) solidifying the slag after metallization of the ferrous oxide to form a matrix of titanium oxide-rich slag having a plurality of metallic iron granules distri

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: 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 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 of cold starting a molten bath-based direct smelting process for producing molten iron in a vessel (3) is disclosed. The method includes a step of preheating the vessel before supplying solid feed materials into the vessel. The method also includes a subsequent step of supplying an oxygen-containing gas and solid feed materials including material for forming slag, iron-containing feed material, and carbonaceous material into the vessel and generating heat and forming a bath of molten material that includes molten iron and molten slag in the vessel.

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.

Abstract: Systems and methods for use in processing raw material (e.g., iron bearing material) include a linear furnace apparatus extending along a longitudinal axis between a charging end and a discharging end (e.g., the linear furnace apparatus includes at least a furnace zone positioned along the longitudinal axis). Raw material is provided into one or more separate or separable containers (e.g., trays) at the charging end of the linear furnace apparatus. The separate or separable containers are moved through at least the furnace zone and to the discharging end where the processed material is discharged resulting in one or more empty containers. One or more of the empty containers are returned to the charging end of the linear furnace apparatus to receive further raw material.

Abstract: The present invention provides: a method for drying compacts containing water so as not to cause explosion and powdering; a method for reducing the compacts after being dried with great efficiency in a rotary-hearth-type reducing furnace; and a rotary-hearth-type metal reducing furnace. In the present invention, when compacts comprising powder containing metal oxide and carbon are dried, the critical value of a water evaporation rate, beyond which explosion occurs, is determined from the size and porosity of the compacts, then the water evaporation rate is controlled to a value not exceeding the critical value and, by so doing, the increase in the internal pressure of the compacts caused by the generation of water vapor is prevented. By the method, the explosion and cracking of the compacts are prevented.

Abstract: The present invention is intended to provide a method for producing metallic iron, which comprises the steps of supplying a mixture containing a carbonous reducing agent and iron oxides onto a hearth of a reduction melting furnace of the moving hearth type, heating the mixture for reduction melting of the iron oxides, cooling thus-obtained metallic iron, and discharging the metallic iron to the outside of the furnace for recovery. The method can easily remove or repair the surface of a hearth even when metallic iron powder is buried in the hearth surface or even when the hearth surface suffers from slag infiltration and erosion, can increase an availability factor and maintainability of the hearth, and is suitably practiced for long-term continuous operation.

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: The invention is a method and apparatus for iron-making/steel-making 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 metallized iron. The pre-reduced metallized iron 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. Nascent slag separates from the molted iron forming carburized iron nuggets. The nuggets are cooled, and then the iron nuggets and the hearth conditioners, including the refractory compounds, are discharged onto a screen, which separate the iron nuggets from the hearth conditioner.

Abstract: A method for heating, reducing and melting a raw material mixture containing carbonaceous reducing agents and an iron oxide-contained substance to manufacture metallic iron, characterized in that a liquid fraction in a solid and liquid coexisting phase of produced slag containing a multi-component gangue is controlled to thereby accelerate melting of solid metallic iron produced.

Abstract: A method of manufacturing a molten metal iron by charging a starting material at least comprising a carbonaceous reducing material and an iron oxide-containing material into a rotary hearth furnace, reducing under heating the charged starting material into a solid reducing iron, carburizing the metal iron in the solid reduced iron with the carbon ingredient in the carbonaceous reducing material, thereby melting the metal iron, separating the slag ingredient contained in the starting material by the melting, and discharging the molten metal alloy in the molten state as it is to the outside of the rotary hearth furnace for recovery, wherein a downward inclined surface is disposed at an angle 3 to 30° relative to the horizontal plane on the upper surface of a hearth of the rotary hearth furnace on which the starting material is placed, and the molten metal iron is discharged at the discharging position for the molten metal iron from the lowest portion of the inclined surface.

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 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: Traveling hearth furnace and an operating method thereof, which, when stacking a layer consisting of a mixture of oxides such as fine iron ore and a fine solid reducing material onto a horizontally traveling hearth and reducing the oxides through radiant heat transfer from above the hearth, is based on melting the reduction product in the course of up to a discharge port, and causing aggregation and separation of slag in from the reduction product, followed by solidifying the reducible material.

Abstract: A method of making metallic iron includes heating a mixed powder containing iron oxide and a carbonaceous reducing agent on a hearth to reduce the iron oxide and melt the reduced iron. Preliminary molding of the mixed powder starting material into pellets is not required. The resulting metallic iron contains extremely low concentrations of slag ingredients, even when the mixed powder starting material contains only low concentrations of iron oxide.

Abstract: Producing reduced metal by charging and stacking a raw material containing a metal-containing material and a solid reducing material on a horizontally moving hearth of a traveling hearth furnace, by disposing a solid reducing material layer on the hearth, forming concave portions at the solid reducing material surface, stacking the raw material on the surface of the solid reducing material layer, reducing raw material by at least once heating and melting the material on the hearth to separate metal and gangue and ash ingredients, and discharging metal from the hearth.

Abstract: A method and apparatus for producing direct reduced iron from dry compacts composed of iron oxide and carbonaceous material by feeding compacts no more than two layers deep onto a hearth and removing all the volatiles and metallizing the compacts by exposing said compacts to a radiant heat source at a temperature of from about 2400.degree. to about 2600.degree. F (1316.degree.-1427.degree. C.) for a total time period of about four to ten minutes and partially cooling the compacts while discharging them from the hearth.