Abstract: In accordance with the present invention, there is provided a process for producing hydrogen and graphitic carbon from a hydrocarbon gas comprising: contacting at a temperature between 600° C. and 1000° C. the catalyst with the hydrocarbon gas to catalytically convert at least a portion of the hydrocarbon gas to hydrogen and graphitic carbon, wherein the catalyst is a low grade iron oxide.
Abstract: A method and apparatus for producing direct reduced iron using a pre-treated make-up gas as a reducing agent in a direct reduced iron reactor are provided. The method involves pre-treating a stream of make-up gas containing heavy hydrocarbons by subjecting the stream to low temperature adiabatic reforming at a temperature between 300° C. and 600° C., prior to using the stream of make-up gas as a reducing agent for producing direct reduced iron. The method also involves adjusting the humidity content of the stream of make-up gas after the low temperature adiabatic reforming by bypassing the stream to selectively split it into a first part of the stream of make-up gas and a second part of the stream of make-up gas, subjecting the first part to water separation, and then mixing the first part with the second part to obtain a reducing stream to be sent to direct reduced iron production.
Type:
Grant
Filed:
August 2, 2017
Date of Patent:
December 21, 2021
Assignees:
DANIELI & C. OFFICINE MECCANICHE S.P.A, HYL TECHNOLOGIES S.A. DE C.V.
Abstract: A process for reducing iron oxide to metallic iron using coke oven gas (COG), including: a direct reduction shaft furnace for providing off gas; a COG source for injecting COG into a reducing gas stream including at least a portion of the off gas; and the direct reduction shaft furnace reducing iron oxide to metallic iron using the reducing gas stream and injected COG. The COG has a temperature of about 1,200 degrees C. or greater upon injection. The COG has a CH4 content of between about 2% and about 13%. Preferably, the COG is reformed COG. Optionally, the COG is fresh hot COG. The COG source includes a partial oxidation system. Optionally, the COG source includes a hot oxygen burner.
Type:
Grant
Filed:
January 31, 2012
Date of Patent:
April 1, 2014
Assignee:
Midrex Technologies, Inc.
Inventors:
Gary E. Metius, James M. McClelland, Jr., David C. Meissner
Abstract: A process for the direct reduction of iron ore when the external source of reductants is one or both of coke oven gas (COG) and basic oxygen furnace gas (BOFG). Carbon dioxide (CO2) is removed from a mixture of shaft furnace off gas, obtained from a conventional direct reduction shaft furnace, and BOFG. This CO2 lean gas is mixed with clean COG, humidified, and heated in an indirect heater. Oxygen (O2) is injected into the heated reducing gas. This hot reducing gas flows to the direct reduction shaft furnace for use. The spent hot reducing gas exits the direct reduction shaft furnace as shaft furnace off gas, produces steam in a waste heat boiler, is cleaned in a cooler scrubber, and is compressed and recycled to join fresh BOFG. A portion of the shaft furnace off gas is sent to the heater burners. The BOFG and COG are also employed for a variety of other purposes in the process.
Type:
Grant
Filed:
May 13, 2011
Date of Patent:
July 30, 2013
Assignee:
Midrex Technologies, Inc.
Inventors:
Gary E. Metius, James M. McClelland, Jr., David C. Meissner
Abstract: Disclosed is a composite system that includes a reduction system for reducing oxides in a continuous process, a process assembly for manufacturing liquid metal in a discontinuous process, wherein a reduction product is fed from the reduction system to the process assembly, at least one buffer device for receiving the reduction product and further starting materials and also for charging the process assembly, and a conveyor system for transporting the reduction product from the reduction system into the at least one buffer device.
Type:
Grant
Filed:
November 16, 2010
Date of Patent:
June 19, 2012
Assignee:
Siemens Vai Metals Technologies GmbH
Inventors:
Harald Fischer, Ernst Oberndorfer, Hanspeter Ofner, Wilhelm Schiffer
Abstract: A method for filtering molten magnesium or magnesium alloys is provided. The method includes the steps of: providing an organic foam; impregnating the organic foam with a slurry comprising metal particles; heating the impregnated organic foam to a temperature sufficient to volatilize the organic foam thereby forming a porous metal foam comprising no more than 0.5 wt % nickel; sintering the porous metal foam; passing molten magnesium or magnesium alloy through the porous metal foam thereby forming purified molten magnesium or magnesium alloy; and cooling the purified molten magnesium or magnesium alloy.
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.
Type:
Grant
Filed:
December 7, 2005
Date of Patent:
January 5, 2010
Assignee:
Nu-Iron Technology, LLC
Inventors:
Iwao Iwasaki, Michael J. Lalich, Robert C. Beaudin, Richard F. Kiesel, Andrew J. Lindgren, Rodney L. Bleifuss
Abstract: To produce metallic iron from iron ore, a composition comprising a mass of material formed from a mixture of iron ore particles and particles of a reductant that is either a biomass material in particulate form or a plastic resinous material in particulate form is used. The reductant can also be a mixture of biomass material and resin in any proportions. The mass of material comprises at least one body having a shape adapted for smelting such as pellets, briquettes, pieces or lumps. The pellets have sufficient cohesion to maintain the shape into which they have been formed.
Type:
Grant
Filed:
March 9, 2007
Date of Patent:
December 15, 2009
Assignee:
Michigan Technological University
Inventors:
Timothy C. Eisele, Surendra Komar Kawatra
Abstract: In a process for reducing iron-ore-containing particulate material in at least a two-stage process, reducing gas is conducted through at least two reaction zones consecutively arranged in series and formed by a moving particulate material and the particulate material passes through the reaction zones in reverse order to the reducing gas, with the particulate material being heated in the reaction zone arranged first for the particulate material and being reduced in the further reaction zone.
Abstract: Apparatus and process for producing a fixed bed in a metallurgical unit, preferably for producing pig iron or primary steel products from iron-containing charge materials, in particular in a melted gasifier, in which a lumpy bulk material, which contains ore-containing and carbon-containing constituents, prereduced iron ore, preferably sponge iron, and preferably lumpy, coal, is charged onto a surface. Through mixing of the ore-containing constituent with the carbon-containing constituent of the bulk material takes place. The entire ore-containing constituent is charged onto an active circumferential or peripheral region of the fixed bed, at which the thorough, preferably uniform mixing of the ore-containing constituent with the carbon-containing constituent of the bulk material takes place preferably outward of the center. A device scatters the stream of bulk material aver the surface and less of the material is scattered at the center, so that heavier grain lumps segregate themselves toward the center.
Abstract: The solids will first of all reach a first container under atmospheric pressure and then reach a second container of variable pressure, which is disposed thereunder, before they are introduced into the pressure vessel. The first and the second container each have a lower outlet passage and a movable shutter cooperating with the outlet passage. The outlet end of the outlet passage is disposed 20 to 400 mm above the shutter in the closed position, in the closed position the shutter forms the bottom of a chamber at least partly filled with solids. The chamber is connected with the outlet passage in a gastight way, and there is no gastightness between the chamber and the shutter. In the closed position, the shutter carries a solid bed, a vertical solid column having a height of at least 1 m is present in the outlet passage and in the container. In the closed position, seal gas is pressed into the chamber and into the solid column from the outside.
Type:
Grant
Filed:
August 8, 2001
Date of Patent:
January 13, 2004
Assignee:
MG Technologies AG
Inventors:
Rüdiger Deppe, Klaus Kanschik, Andreas Orth
Abstract: Method for the direct reduction of mineral iron inside a vertical reduction furnace (10) of the type with a gravitational load, wherein the reduction gas flows in counter-flow with respect to the material introduced into the furnace, comprising the following steps: the mineral iron is fed from above into the furnace (10), a mixture of high temperature gas consisting of reducing gas based on H2 and CO is injected, and the reduced mineral is removed from the furnace (10), the mixture of gas being introduced in at least two zones (12, 14) of the furnace (10) arranged one above the other so as to achieve, in a controlled manner, a first stage of pre-heating and pre-reduction in the upper part (12) of the furnace (10) and a second stage of final reduction in the lower part (14) of the furnace (10).
Type:
Grant
Filed:
December 10, 1999
Date of Patent:
November 20, 2001
Assignee:
Danieli & C. Officine Meccaniche SpA
Inventors:
Henry Rafael Bueno, David Rabascall, Gianpietro Benedetti
Abstract: A method for effecting direct reduction of iron oxides in the form of lumps or pellets, in which an ore burden is passed downwardly successively through prereduction and metallization zones of a shaft furnace while passing a flow of rich fuel gas produced by external partial combustion upwardly in counter current through the prereduction zone, and passing a flow of reducing gas in cocurrent though the metallization zone. The flow of reducing gas is an independent flow that has not been subject to external combustion, and an intermediate zone is provided forming a narrowed throat between the prereduction and metallization zones. The reducing gas is introduced at a boundary between the intermediate and metallization zones, such that passage of rich fuel gas from the prereduction zone to the metallization zone is inhibited. The gas flows should be controlled so that about 5% to 10% of the volume of reducing gas passes upwardly from the intermediate zone to the prereduction zone.
Abstract: The invention relates to a process for the reduction of metal-oxide-bearing material, particularly of iron ore, in a reduction vessel (1), wherein the metal-oxide-bearing material is charged from a vessel (2) for the metal-oxide-bearing material into the reduction vessel (1) and reduced therein by means of a reduction gas flowing counter currently to the metal-oxide-bearing material and wherein waste reduction gas discharged from the reduction vessel (1) is used for preheating the metal-oxide-bearing material in the vessel (2) for metal-oxide-bearing material, which is characterized in that the waste reduction gas discharged from the reduction vessel (1) is combusted and that a gas seal (16) is operated with the combusted waste reduction gas, which is located between the reduction vessel (1) and the vessel (2) for metal-oxide-bearing material, whereby the reduction vessel (1) is sealed against the vessel (2) for metal-oxide-bearing material (FIG. 1).
Abstract: A method and apparatus for simultaneously supplying varying proportions of hot and cold direct reduced iron(DRI) material from a source of hot DRI for melting, storage, briquetting, or transport. The system uses gravity to transport hot DRI material from a reduction furnace to a furnace discharge section, which transports desired amounts to a cooling receptacle and to a hot DRI vessel. The cooling section of the apparatus is connected to the furnace discharge section through a dynamic seal leg. The hot section is also connected to the furnace discharge section through separate a dynamic sealing leg and can feed a surge vessel, a briquetter, a storage vessel or a melting furnace. The method of operation is also disclosed.
Type:
Grant
Filed:
October 8, 1999
Date of Patent:
April 10, 2001
Assignee:
Midrex International B.V. Rotterdam, Zurich Branch
Inventors:
Stephen Craig Montague, Brian William Voelker
Abstract: Gravitational type furnace for the direct reduction of mineral iron comprising a median reaction zone (14) in which the reactions to reduce the mineral iron occur, means (11) to feed the mineral iron to said reaction zone (14), means (18) to introduce a mixture of reducing gas into said reaction zone (14) and means (15) to discharge the reduced metal iron, said discharge means comprising at least two extremities (15a-15c), shaped like a cone or a truncated cone, with the taper facing downwards, each of which being provided with a corresponding lower aperture (16a-16c) through which said reduced metal iron can be selectively discharged in a controlled and independent manner.
Type:
Grant
Filed:
December 10, 1999
Date of Patent:
December 19, 2000
Assignee:
Danieli & C. Officine Meccaniche SpA
Inventors:
Henry Rafael Bueno, David Rabascall, Gianpietro Benedetti
Abstract: An apparatus for the direct reduction of iron oxide utilizing a shaft furnace equipped with a bustle and tuyere system having multiple rows of tuyeres. The bustle and tuyere system utilizes multiple rows of tuyeres to aid in the reduction of gas velocities through the system and to improve burden flow.
Type:
Grant
Filed:
January 8, 1999
Date of Patent:
November 14, 2000
Assignee:
Midrex International B.V. Rotterdam, Zurich Branch
Abstract: A method and apparatus for producing DRI, prereduced materials, or the like, utilized in the steelmaking industry, where hydrogen contained in the gas stream purged from the reduction reactor is separated (preferably by means of a PSA system) and recycled to said reduction reactor. The productivity of the reduction plant is increased by using the separated hydrogen as a chemical reductant in the reactor, instead of using it as fuel. This is particularly useful in upgrading existing DRI production plants.
Abstract: Method and apparatus for the production of prereduced iron ore, Direct Reduced Iron (DRI), or the like, in an ironmaking plant wherein the reducing gas utilized in the chemical reduction of iron oxides is generated from natural gas within the reduction reactor system by reforming the hydrocarbons with such oxidants as water and oxygen inside the reduction reactor which under steady state conditions contains metallic iron which acts as a reformation catalyst. The amount of carbon in the DRI can be reliably controlled by modifyng the relative amounts of water, carbon dioxide and oxygen in the composition of the reducing gas fed to the reduction reactor. The amount of carbon in the DRI is controlled by the amount of water in the reducing gas fed to the reduction reactor while the addition of oxygen provides the energy necessary for such DRI carburization.
Abstract: A direct ironmaking process in which coal and oxygen are used directly for reducing ore and smelting the resulting sponge iron wherein a high-temperature ion transport membrane process recovers oxygen for use in the ironmaking process. Heat for oxygen recovery is provided by combustion of medium-BTU fuel gas generated by the ironmaking process and/or by heat exchange with hot gas provided by the ironmaking process. The ironmaking and oxygen recovery processes can be integrated with a combined cycle power generation system to provide an efficient method for the production of iron, oxygen, and electric power.
Type:
Grant
Filed:
April 6, 1995
Date of Patent:
July 1, 1997
Assignee:
Air Products and Chemicals, Inc.
Inventors:
Rakesh Agrawal, Michael Shi-Kuan Chen, Arthur Ramsden Smith, Robert Michael Thorogood, Thomas Joseph Ward
Abstract: Apparatus for the production of iron carbide in a shaft furnace, by reacting a carbon containing reducing gas as the process gas with particulate metal oxide material for an extended residence time at low temperature, including residence time and operating temperature controls. The resulting iron carbide product is also disclosed.
Type:
Grant
Filed:
May 5, 1995
Date of Patent:
April 8, 1997
Assignee:
Midrex International B.V. Rotterdam, Zurich Branch
Abstract: A method and apparatus for the production of iron carbide in a shaft furnace, by reacting a carbon containing reducing gas as the process gas with particulate metal oxide material for an extended residence time at low temperature.
Type:
Grant
Filed:
May 4, 1994
Date of Patent:
August 1, 1995
Assignee:
Midrex International B.V. Rotterdam, Zurich Branch
Abstract: A process for the direct reduction of metal oxides containing iron to obtain a DRI metallized iron product comprises feeding heavy hydrocarbon oil under controlled conditions to a cracking zone upstream of the reduction reactor so as to form a cracked product rich in CH.sub.4 and thereafter feeding said cracked product directly to the reaction zone wherein a reformed reducing gas rich in H.sub.2 and CO is formed and contacted with said iron oxide material thereby effecting reduction of said iron oxide material in the reaction zone.
Abstract: The present invention relates to a process for the production of liquid steel from iron containing metal oxides and, more particularly, a process for the direct production of iron-containing metal oxides wherein the hot discharge of direct reduced iron (DRI or sponge iron) is fed to a melting furnace with the process gases from the direct production furnace for refining the DRI to liquid steel.
Type:
Grant
Filed:
April 20, 1990
Date of Patent:
December 3, 1991
Assignee:
C.V.G. Siderurgica del Orinoco, C.A.
Inventors:
Oscar G. Dam G., Henry R. Bueno C., Gerardo A. Contreras L., Yura Gancthev V., Nicolas O. Guevara R.
Abstract: A process for the direct reduction of iron-containing metal oxides to obtain iron is disclosed in which a reformed reduction gas rich in H.sub.2 and CO and having an oxidation degree in the range of from about 0.30 to about 0.35 is formed and reduction is carried out simultaneously in a single reaction zone of a reduction reactor. The reformed reduction gas is formed using a highly endothermic reaction during which a mixture of heated natural gas, recycled top gas and air, preferably oxygen enriched air, is placed into contact with heated surfaces of DRI metallized iron in the reaction zone. The resulting reformed reducing gas consists essentially of from about 45% to about 48% hydrogen, from about 32% to about 34% carbon monoxide, from about 2% to about 4% carbon dioxide, from about 1% to about 3% methane, from about 14% to about 16% nitrogen and from about 1% to about 3% water vapor.