Nu-iron Technology, Llc.

David J Englund

Rodney L Bleifuss

Richard F Kiesel

Iwao Iwasaki

Bradford G True

Donald Fosnacht

Mark M Brandon

Mark Schlichting

John Meehan

Jeremiah Crouch

Logan Wilson

Andrew J Lindgren

Dave Hendrickson

Rodney Bleifuss

A method and system for making metallic iron nodules with reduced COemissions 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.

[object Object]

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.

System and method for producing metallic iron

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.

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.

Method and system for producing metallic iron nuggets

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

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

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.

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Bovey, MN, United States of America

David J Englund