Nu-iron Technology, Llc.

University of Minnesota

Other

Iwao Iwasaki

Rodney L Bleifuss

Richard F Kiesel

Andrew J Lindgren

David J Englund

Michael J Lalich

Robert C Beaudin

Donald Fosnacht

Bradford G True

Mark M Brandon

David W Hendrickson

Dave Hendrickson

Rodney Bleifuss

Andrew L Lindgren

Michael C Lalich

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.

Use of bimodal carbon distribution in compacts for producing metallic iron nodules

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/SiObetween 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.

Production of iron from metallurgical waste

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.

System and method for producing metallic iron

Method and system for producing metallic nuggets includes providing reducible mixture of reducing material (such as carbonaceous material) and reducible iron bearing material (such as iron oxide) that may be arranged in discrete portions, such as mounds or briquettes, on at least a portion of a hearth material layer (such as carbonaceous material). A coarse overlayer of carbonaceous material may be provided over at least some of the discrete portions. Heating the reducible mixture to 1425&#xb0; C. or 1400&#xb0; C. or 1375&#xb0; 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.

Method and system for producing metallic iron nuggets

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&#xb0; C. or 1400&#xb0; C. or 1375&#xb0; 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.

A hearth furnacefor producing metallic iron material has a furnace housingwith a drying/preheat zonecapable of providing a drying/preheat atmosphere for reducible material, a conversion zonecapable of providing a reducing atmosphere for reducible material, a fusion zonecapable of providing an atmosphere to at least partially reduced metallic iron material, and optionally a cooling zonecapable of providing a cooling atmosphere for reduced material containing metallic iron material. A hearthis movable within the furnace housingin a direction through the drying/preheat zone, then the conversion zone, then the fusion zone, and then the cooling zone. A separation barrieris positioned within at least a portion of the conversion zone, the separation barrierseparating the conversion zoneinto a combustion regionand a reducing regionwith the reducing regionadjacent the hearthand the combustion regionadjacent the reducing regionand spaced from the hearth

System and method of producing metallic iron

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.

A hearth furnacefor producing metallic iron material has a furnace housinghaving a drying/preheat zone, a conversion zone, a fusion zone, and optionally a cooling zone, the conversion zoneis between the drying/preheat zoneand the fusion zone. A moving hearthis positioned within the furnace housing. A hood or separation barrierwithin at least a portion of the conversion zone, fusion zoneor both separates the fusion zoneinto an upper region and a lower region with the lower region adjacent the hearthand 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.

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&#xb0; F. (1200 and 1450&#xb0; 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.

System and method for producing metallic iron nodules

A separation apparatus and method for use in separating magnetic material from non-magnetic material that includes the use of a magnetic grid, e.g., a permanently magnetic grid, which defines a plurality of openings. The grid assists in preventing magnetic material from being transported to an overflow.

Growing community of inventors

Grand Rapids, MN, United States of America

Iwao Iwasaki