Midrex International, B.v., Rotterdam, Zurich Branch

Cardero Resource Corporation

Midrex Technologies, Inc.

Midrex International B.v. Rotterdam

Hoffman & Sons Technologies, LLC

Glenn E Hoffman

David C Meissner

Ronald D Gray

Kyle J Shoop

Isao Kobayashi

Shoichi Kikuchi

Shuzo Ito

Koji Tokuda

John C Scarlett

Osamu Tsuge

James M McClelland, Jr

Akira Uragami

Yasuhiro Tanigaki

Takuya Negami

Bradford G True

Frank V Summers

Robert M Klawonn

A process for recovering pig iron from iron-containing concentrates produced from iron-containing ores and sands by forming agglomerates and reducing them in a natural gas smelter, in which the process makes maximum utilization of heat created in and by the process.

Producing of pig iron from iron-containing materials

A method for producing liquid ferroalloy by direct processing of manganese and chromium bearing iron compounds, by the steps: of mixing carbonaceous reductant, fluxing agent, and a binder with materials such as iron sands, metallic oxides, manganese-iron ore concentrates and/or chromium-iron ore concentrates and silica sands, to form a mixture; forming agglomerates from the mixture; feeding the agglomerates to a melting furnace with other materials; melting the feed materials at a temperature of from 1500 to 1760&#xb0; C. and forming a slag and hot metal; removing the slag; tapping the hot metal as liquid ferroalloy, and utilizing the off-gases from the melting furnace as combustion fuel to drive a turbine and to generate electricity.

Direct processing of metallic ore concentrates into ferroalloys

Apparatus for producing lead and zinc from concentrates of zinc and lead sulfides or oxides, including: a source of zinc ore and/or lead ore concentrates, iron bearing and carbon containing materials; metallic iron fines and iron oxide fines; carbonaceous reductant; fluxing agent; and a binder; a mixer for forming a mixture from said concentrates and other materials; an agglomerator communicating with the mixer for forming agglomerates from the mixture; a melting furnace for melting the mixture and vaporizing lead and zinc; a pressure sealed feed system communicating with the agglomerator and the melting furnace for introducing agglomerates to the melting furnace; a pressure sealed chamber surrounding the melting furnace; a water-cooled condenser for receiving the vaporized metal and cooling and condensing the metal vapors to liquid metal; a tapping device communicating with the condenser for removing the liquid metal; and associated devices for separating the zinc and lead and recovering the lead and zinc metal separately.

Apparatus for direct smelting of zinc bearing compounds to produce metallic zinc

A process and apparatus for producing lead and zinc from concentrates of zinc and lead sulfides or oxides includes the steps of:

Direct smelting of zinc bearing compounds to produce metallic zinc

A method for producing pig iron by direct processing of ferrotitania sands, by the steps of:

Direct processing of ferrotitania ores and sands

The invention is a method of making metallized iron agglomerates by combining iron/steel particles and a reductant material with a cellulose fiber binder material, compacting the combination to form a solid agglomerate, and reducing the iron portions of the agglomerate in a direct reduction furnace. The cellulose fiber binder material provides an agglomerate having improved strength and lower overall cost than comparable agglomerates using binders known in the art.

Method of producing a metallized briquette

An apparatus and method for the direct reduction of iron oxide utilizes a hearth furnace having a vitreous hearth layer of conditioning materials, with the vitreous hearth layer introduced onto a refractory surface of the furnace. The vitreous hearth layer may have upper layers of coating compounds including carbonaceous materials, onto which iron oxide feed material is placed with the carbonaceous materials assisting with segregating the reduced molten iron nuggets from the vitreous hearth layer. The conditioning materials may include compounds such as silicon oxide, magnesium oxide, iron oxides, and aluminum oxide. The conditioning materials are placed in solid or liquid form on the refractory surface, which allows the conditioning materials to raise the melting temperature of the vitreous hearth layer onto which the coating compounds and iron oxide materials are placed. The iron oxide materials form molten metal nuggets of high purity iron and residual carbon, which remains separate from the vitreous hearth layer due to the layer of coating compounds. The invented apparatus and method of operation provide a solid iron and carbon product having high iron purity, which is discharged from the furnace without significant loss of iron onto the interior surfaces of the hearth furnace, and with limited buildup of hardened films of metallized iron product within the hearth.

Furnace hearth for improved molten iron production and method of operation

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. The hearth conditioner is recycled, and the melted agglomerates are prepared for sale or for additional treatment in a final melter, where the final melter is preferably an electric furnace. Exhaust gases from the FHM furnace are recovered for calcining coal into fuel gases and coke.

Method for producing beneficiated titanium oxides

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. The hearth conditioner is recycled, and the iron nuggets are either prepared for sale or for additional treatment, such as alloying, in a final melter, where the final melter is preferably an electric furnace. Exhaust gases from the FHM furnace are recovered for calcining coal into fuel gases and coke.

Method of direct iron-making / steel-making via gas or coal-based direct reduction and apparatus

This invention relates to a method for operation of a moving hearth furnace in conjunction with an electric melter for production of high purity iron product having a range of silicon and manganese, with low sulfur and phosphorus content. The method includes producing high purity iron product and a range of carbon content product from iron oxide and carbon bearing agglomerates, including the steps of providing a furnace for direct reduction of iron oxide and carbon bearing agglomerates, pre-reducing iron and carbon bearing agglomerates in a furnace having a moving hearth surface, producing intermediate carbon-containing metallized iron. An electric melter furnace is utilized for receiving intermediate carbon-containing metallized iron from the pre-reducing step, which is fed directly and continuously into a central interior area of the electric melter, with heating of the carbon-containing metallized iron in the electric melter under elevated temperatures of about 1300&deg; C. to about 1700&deg; C., minimizing the ingress of air or other undesirable gases such as oxygen in the melting step while maintaining elevated temperatures, and removing high purity liquid iron product from the electric melter. The method provides a high iron content product having a specified range of carbon, silicon, and manganese percentages, with low sulfur and phosphorus content. There is significant reduction of silicon oxides, and reduction of manganese oxides in the product. An extremely desirable high iron content product is produced for use by the steelmaking industry.

Method for producing molten iron in duplex furnaces

The present invention is an apparatus and method for the direct reduction of iron oxide utilizing a rotary hearth furnace to form a high purity carbon-containing iron metal button. The hearth layer may be a refractory or a vitreous hearth layer of iron oxide, carbon, and silica compounds. Additionally, coating materials may be introduced onto the refractory or vitreous hearth layer before iron oxide ore and carbon materials are added, with the coating materials preventing attack of the molten iron on the hearth layer. The coating materials may include compounds of carbon, iron oxide, silicon oxide, magnesium oxide, and/or aluminum oxide. The coating materials may be placed as a solid or a slurry on the hearth layer and heated, which provides a protective layer onto which the iron oxide ores and carbon materials are placed. The iron oxide is reduced and forms molten globules of high purity iron and residual carbon, which remain separate from the hearth layer. An improved apparatus includes a cooling plate that is placed in close proximity with the refractory or vitreous hearth layer, cooling the molten globules to form iron metal buttons that are removed from the hearth layer. The improvements due to the present apparatus and method of operation provide high purity iron and carbon solid buttons, which are separate from slag particulates, and discharged without significant loss of iron product to the interior surfaces of the furnace.

Iron production method of operation in a rotary hearth furnace and improved furnace apparatus

This invention relates to a method for operation of a rotary hearth furnace in conjunction with an electric melter for production of high purity iron product having a range of silicon and manganese, with low sulfur and phosphorus content. The method includes producing high purity iron product and a range of carbon content product from iron oxide and carbon bearing compacts, including the steps of providing a furnace for direct reduction of iron oxide and carbon bearing compacts, pre-reducing iron and carbon bearing compacts in a furnace having a rotary hearth surface, producing intermediate carbon-containing metallized iron. An electric melter furnace is utilized for receiving intermediate carbon-containing metallized iron from the pre-reducing step, which is fed directly and continuously into a central interior area of the electric melter, with heating of the carbon-containing metallized iron in the electric melter under elevated temperatures of about 1300&deg; C. to about 1700&deg; C., minimizing the ingress of air or other undesirable gases such as oxygen in the melting step while maintaining elevated temperatures, and removing high purity liquid iron product from the electric melter. The method provides a high iron content product having a specified range of carbon, silicon, and manganese percentages, with low sulfur and phosphorus content. There is significant reduction of silicon oxides, and reduction of manganese oxides in the product. An extremely desirable high iron content product is produced for use by the steelmaking industry.

Method of producing molten iron in duplex furnaces

A method for producing solid metal product is disclosed including the steps of providing carbon and metal bearing compounds in compacts, coating the compacts with treatment materials, encapsulating the compacts with carbonaceous containing materials to form a residual layer, and treating the residual layer before introduction of the compacts into a furnace. The compacts contain carbon containing metal bearing compounds, and are coated with mixtures of carbonaceous materials dispersed within a binder material such as a viscous liquid, molasses, alcohol, or fuel oil. The coated compacts are treated to form a hardened outer residual layer. The outer residual layer provides for a sacrificial outer coating on the compacts that reacts with any oxidizing gaseous components within the furnace, while the carbon containing metal bearing compounds within the compacts are heated and metallized inside the compounds. The outer residual layer provides for improved production of higher purity of metal and carbon nuggets with decreased furnace processing times. Therefore, an increase in purity of the metal product is produced at a lower cost, with minimization of the interaction of the molten metal and slag from nuggets with the furnace hearth surface.

Treatment of iron oxide agglomerates before introduction into furnace

A method of making a molten ferroalloy product in a melting furnace by charging a briquet consisting essentially of metallized iron, granulated alloy metal oxide, and a carbon source, such as coke breeze, to the melting furnace, burning solid carbonaceous material to reduce the alloy metal oxide to metallized form and to heat the charge to form a molten ferroalloy product. Fluxes and slag formers are also charged to the furnace as required.

Method of producing ferro-alloys

A briquet consists essentially of metallized iron fines, formed by direct reduction of iron oxide, granulated or fine silica, a carbon source such as coke breeze, and less than 3.5 percent of other components, or impurities. The briquet product has a density of from 2.0 to 6.0 g/cc, and is particularly well suited for steelmaking operations. The method for making the briquet is also disclosed.

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Lancaster, SC, United States of America

Glenn E Hoffman