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

Abstract: A method for use in production of metallic iron nodules comprising providing a reducible mixture into a hearth furnace for the production of metallic iron nodules, where the reducible mixture comprises a quantity of reducible iron bearing material, a quantity of first carbonaceous reducing material of a size less than about 28 mesh of an amount between about 65 percent and about 95 percent of a stoichiometric amount necessary for complete iron reduction of the reducible iron bearing material, and a quantity of second carbonaceous reducing material with an average particle size greater than average particle size of the first carbonaceous reducing material and a size between about 3 mesh and about 48 mesh of an amount between about 20 percent and about 60 percent of a stoichiometric amount of necessary for complete iron reduction of the reducible iron bearing material.

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

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 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: 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: 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: 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: 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: 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: 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 system and method for cooling and removing metallic iron and other aggregate from a moving hearth is provided. Cooling may be provided by a secondary cooling system and a spray cooling system in a cooling zone. The secondary cooling system may include an arrangement of coolant tubes for absorbing heat. A flow of nitrogen may be provided through the cooling zone. The spray cooling system may provide evaporative cooling. Aggregate removal may be provided by a magnetic removal system, a plow system, and a sweeper system. The magnetic removal system uses a magnetic device and a moving belt to remove iron materials. The plow system uses a plow to separate and remove aggregate from the moving hearth. The sweeper system may use a vacuum device to pull materials from the moving hearth.

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: 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: 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: 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: 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: 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.