Compositions and Methods for Improvement of Blast Furnace Production

The present disclosure provides compositions and methods for improvement of blast furnace production, and, more specifically, pertains to improvements in blast furnace production through increased use of superior quality iron bearing raw material that includes a binder composition mixed therewith to form a mixture that is used to form ore particle agglomerates.

Conventionally, granulation and peptization are methods that can be used to agglomerate mineral particles, such as iron ore, into a product that is fed to a blast furnace. If the particles are too small to feed to the furnace, they typically need to be formed into agglomerates, pellets, sinter etc., to achieve a suitable (larger) size.

Conventional feeds and processes have several shortcomings. For example, conventional methods have used lower quality ores, which causes the resulting products to have a similar lower quality and also makes the overall process increasingly inefficient. Moreover, prior methods have varied the feed mix ratio in an attempt to increase sinter quality but such methods tend to exhibit poor yield percentages, making their implementation infeasible long-term, while also negatively impacting scalability.

In certain aspects, the present disclosure provides a process for preparing an ore particle agglomerate. The process comprises adding a binder composition to a raw material to create a mixture, and forming the ore particle agglomerate from the mixture, wherein the binder composition comprises a modified starch and optionally a dispersant, a metal salt, a surfactant, or any combination thereof.

The present disclosure also provides a process for preparing an ore particle agglomerate comprising adding a binder composition to a raw material to create a mixture, and forming the ore particle agglomerate from the mixture. The binder composition comprises a metal salt and/or a dispersant, and optionally a modified starch, a surfactant, or any combination thereof.

Additionally, the present disclosure provides an ore particle agglomerate comprising a binder composition and ore particles, wherein the binder composition comprises a modified starch, a dispersant, a metal salt, a surfactant, or any combination thereof.

The foregoing has outlined rather broadly the features and technical advantages of the present disclosure in order that the detailed description that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter that form the subject of the claims of this application. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other embodiments for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent embodiments do not depart from the spirit and scope of the disclosure as set forth in the appended claims.

Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present document, including definitions, will control. Examples of methods and materials are described below, although methods and materials similar or equivalent to those described herein can be used in practice or testing of the present disclosure. All publications, patent applications, patents and other reference materials mentioned herein are incorporated by reference in their entirety. The materials, methods, and examples disclosed herein are illustrative only and not intended to be limiting.

Unless otherwise indicated, an alkyl group as described herein alone or as part of another group is an optionally substituted linear or branched saturated monovalent hydrocarbon substituent containing from, for example, one to about sixty carbon atoms, such as one to about thirty carbon atoms, in the main chain. Examples of unsubstituted alkyl groups include methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, n-pentyl, i-pentyl, s-pentyl, t-pentyl, and the like.

The terms “aryl” or “ar” as used herein alone or as part of another group (e.g., arylene) denote optionally substituted homocyclic aromatic groups, such as monocyclic or bicyclic groups containing from about 6 to about 12 carbons in the ring portion, such as phenyl, biphenyl, naphthyl, substituted phenyl, substituted biphenyl or substituted naphthyl. The term “aryl” also includes heteroaryl functional groups. It is understood that the term “aryl” applies to cyclic substituents that are planar and comprise 4n+2 electrons, according to Huckel's Rule.

“Cycloalkyl” refers to a cyclic alkyl substituent containing from, for example, about 3 to about 8 carbon atoms, preferably from about 4 to about 7 carbon atoms, and more preferably from about 4 to about 6 carbon atoms. Examples of such substituents include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, and the like. The cyclic alkyl groups may be unsubstituted or further substituted with alkyl groups, such as methyl groups, ethyl groups, and the like.

“Heteroaryl” refers to a monocyclic or bicyclic 5- or 6-membered ring system, wherein the heteroaryl group is unsaturated and satisfies Huckel's rule. Non-limiting examples of heteroaryl groups include furanyl, thiophenyl, pyrrolyl, pyrazolyl, imidazolyl, 1,2,3-triazolyl, 1,2,4-triazolyl, isoxazolyl, oxazolyl, isothiazolyl, thiazolyl, 1,3,4-oxadiazol-2-yl, 1,2,4-oxadiazol-2-yl, 5-methyl-1,3,4-oxadiazole, 3-methyl-1,2,4-oxadiazole, pyridinyl, pyrimidinyl, pyrazinyl, triazinyl, benzofuranyl, benzothiophenyl, indolyl, quinolinyl, isoquinolinyl, benzimidazolyl, benzoxazolinyl, benzothiazolinyl, quinazolinyl, and the like.

Compounds of the present disclosure may be substituted with suitable substituents. The term “suitable substituent,” as used herein, is intended to mean a chemically acceptable functional group, preferably a moiety that does not negate the activity of the compounds. Such suitable substituents include, but are not limited to, halo groups, perfluoroalkyl groups, perfluoro-alkoxy groups, alkyl groups, alkenyl groups, alkynyl groups, hydroxy groups, oxo groups, mercapto groups, alkylthio groups, alkoxy groups, aryl or heteroaryl groups, aryloxy or heteroaryloxy groups, aralkyl or heteroaralkyl groups, aralkoxy or heteroaralkoxy groups, HO—(C═O)— groups, heterocylic groups, cycloalkyl groups, amino groups, alkyl- and dialkylamino groups, carbamoyl groups, alkylcarbonyl groups, alkoxycarbonyl groups, alkylaminocarbonyl groups, dialkylamino carbonyl groups, arylcarbonyl groups, aryloxy-carbonyl groups, alkylsulfonyl groups, and arylsulfonyl groups. In some embodiments, suitable substituents may include halogen, an unsubstituted C-Calkyl group, an unsubstituted C-Caryl group, or an unsubstituted C-Calkoxy group. Those skilled in the art will appreciate that many substituents can be substituted by additional substituents.

The term “substituted” as in “substituted alkyl,” means that in the group in question (i.e., the alkyl group), at least one hydrogen atom bound to a carbon atom is replaced with one or more substituent groups, such as hydroxy (—OH), alkylthio, phosphino, amido (—CON(R)(R), wherein Rand Rare independently hydrogen, alkyl, or aryl), amino (—N(R)(R), wherein Rand Rare independently hydrogen, alkyl, or aryl), halo (fluoro, chloro, bromo, or iodo), silyl, nitro (—NO), an ether (—ORwherein Ris alkyl or aryl), an ester (—OC(O)Rwherein Ris alkyl or aryl), keto (—C(O)Rwherein Ris alkyl or aryl), heterocyclo, and the like.

When the term “substituted” introduces a list of possible substituted groups, it is intended that the term apply to every member of that group. That is, the phrase “optionally substituted alkyl or aryl” is to be interpreted as “optionally substituted alkyl or optionally substituted aryl.”

The terms “polymer,” “copolymer,” “polymerize,” “copolymerize,” and the like include not only polymers comprising two monomer residues and polymerization of two different monomers together, but also include (co) polymers comprising more than two monomer residues and polymerizing together more than two or more other monomers. For example, a polymer as disclosed herein includes a terpolymer, a tetrapolymer, polymers comprising more than four different monomers, as well as polymers comprising, consisting of, or consisting essentially of two different monomer residues. Additionally, a “polymer” as disclosed herein may also include a homopolymer, which is a polymer comprising a single type of monomer unit.

Unless specified differently, the polymers of the present disclosure may be linear, branched, crosslinked, structured, synthetic, semi-synthetic, natural, and/or functionally modified. A polymer of the present disclosure can be in the form of a solution, a dry powder, a liquid, or a dispersion, for example.

The present disclosure relates to binder compositions and methods of forming ore particle agglomerates. The term “agglomerate” as used herein refers to particles created by aggregating/binding/agglomerating raw materials. The shape of the agglomerate is not particularly limited and may be selected from, for example, a sphere, pellet, briquette, or a different geometrical shape. The size of the agglomerate is also not particularly limited.

For example, if the shape of the agglomerate is a sphere, the diameter of the sphere may be from about 1 mm to about 50 mm, about 1 mm to about 45 mm, about 1 mm to about 40 mm, about 1 mm to about 35 mm, about 1 mm to about 30 mm, about 1 mm to about 25 mm, about 1 mm to about 20 mm, about 1 mm to about 15 mm, about 1 mm to about 10 mm, about 1 mm to about 5 mm, about 5 mm to about 50 mm, about 10 mm to about 50 mm, about 20 mm to about 50 mm, about 30 mm to about 50 mm, about 40 mm to about 50 mm, or greater than about 50 mm, such as about 50 to about 100 mm or about 50 to about 1,000 mm.

If the shape of the agglomerate is a briquette or a cube, for example, the length, width, and or height may be independently selected from about 1 mm to about 50 mm, about 1 mm to about 45 mm, about 1 mm to about 40 mm, about 1 mm to about 35 mm, about 1 mm to about 30 mm, about 1 mm to about 25 mm, about 1 mm to about 20 mm, about 1 mm to about 15 mm, about 1 mm to about 10 mm, about 1 mm to about 5 mm, about 5 mm to about 50 mm, about 10 mm to about 50 mm, about 20 mm to about 50 mm, about 30 mm to about 50 mm, about 40 mm to about 50 mm, or greater than about 50 mm, such as about 50 mm to about 100 mm or about 50 mm to about 1,000 mm.

In some embodiments, the binder composition may include a modified starch. Such a binder composition may optionally include (or exclude) an additional component, such as a dispersant and/or a stabilizer, a metal salt, a surfactant, or any combination thereof.

In other embodiments, the binder composition includes a metal salt, such as a magnesium salt, and a dispersant, such as a polyacrylate. Such a binder composition may optionally include (or exclude) an additional component, such as modified starch, a stabilizer, a surfactant, or any combination thereof.

In some embodiments, the binder composition may be in the form of a solution, such as an aqueous solution.

The binder composition may be added to raw materials to hold them together to form agglomerates having uniform consistency and/or size. The binder composition may be added to the raw materials as a single composition comprising one or more components, such as modified starch, a metal salt, etc., or one or more of the components of a binder composition may be applied to the raw materials separately. For example, a binder composition comprising modified starch and water may be added to the raw materials and separately, before and/or after the binder composition, a metal salt and/or a dispersant may be added to the raw materials.

The present disclosure further provides a process for preparing ore particle agglomerates that includes adding a binder composition to a raw material to create a mixture, and forming the mixture into agglomerates. “Forming” may include, for example, shaking, mixing, stirring, agitating, or otherwise bringing the raw materials together/in contact with one another such that they contact each other, bind/stick together, and form larger particles.

Typically, the raw materials used for making sinter are mixed together with the addition of water in a mixing drum for agglomeration. The water may be added to the raw materials before, after, and/or during the addition of the binder composition. The amount of water to be added is not particularly limited. In some cases the amount may be enough to achieve a moisture content of about 1% to about 25%, about 1% to about 10%, about 5% to about 20%, about 5% to about 15%, or about 5% to about 10% by weight based on the dry weight of the raw materials.

In some embodiments, the binder composition may be applied to the raw materials in the mixing drum. Additional application locations include, but are not limited to, a pre-mixer, the discharge point of a mixing drum, the discharge point of a pre-mixer, prior to a sintering machine (or a component of a sintering machine), prior to a blast furnace, or any combination thereof. The resulting agglomerates are sometimes referred to as a “greenmix,” which may be subsequently processed into sinter. In some embodiments, the binder composition can be sprayed onto the raw materials and/or greenmix at any location disclosed herein.

The raw material agglomeration process typically requires a large amount of water, which subsequently needs to be evaporated using a significant amount of energy. However, the compositions and methods of the present disclosure allow for the production of a higher quality greenmix using less water than conventional processes, which leads to reduced energy consumption.

The technology disclosed herein provides improved blast furnace production by using higher quality raw materials. The technology allows for the production of high quality sinter by improving the quality of ore-bearing raw materials. For example, the technology reduces fines and ore lumps, which improves hot metal production and reduces consumption of coke while making steel. Moreover, the embodiments of the present disclosure improve sinter gross production, reduce sinter fines, and/or reduce fuel consumption in a sintering process and in a blast furnace operation.

In a process for preparing an ore particle agglomerate of the present disclosure, a binder composition is added to a raw material, which may comprise, for example, one or more ore particles, ore powders, and/or ore fines, to create a mixture.

Ores include rocks and minerals from which a non-metallic ore and/or a metallic ore, such as iron ore, may be extracted. As an example, an iron ore typically includes iron oxides. The iron itself is typically present in the form of magnetite (FeO), hematite (FeO), goethite (FeO(OH)), limonite (FeO(OH)(HO)) or siderite (FeCO). Taconite is an iron-bearing sedimentary rock in which the iron minerals are interlayered with quartz, chert, or carbonate. Itabirite is an iron and quartz formation in which the iron is present as thin layers of hematite, magnetite, or martite. Any of these types of iron may be used in the raw materials for forming an iron ore particle agglomerate as described herein.

In some embodiments, the ore may comprise, for example, iron, taconite, magnetite, hematite, limonite, goethite, siderite, franklinite, pyrite, chalcopyrite, chromite, ilmenite, chrome, copper, nickel, zinc, lead, uranium, barium, or any combination thereof.

In some embodiments, the ore may comprise, for example, phosphate, talc, dolomite, limestone, potassium sulfate, potassium chloride, double sulfate of potassium and magnesium, magnesium oxide, calcium phosphate, carbon black, coal, calcite, quartz, or any combination thereof.

In certain embodiments, the raw materials and/or greenmix may include or exclude iron, coke, coal, mill scale, blast furnace sludge, taconite, magnetite, hematite, limonite, goethite, siderite, franklinite, pyrite, chalcopyrite, chromite, ilmenite, chrome, copper, nickel, zinc, lead, uranium, barium, phosphate rock, talc, dolomite, limestone, potassium sulfate, potassium chloride, double sulfate of potassium and magnesium, magnesium oxide, calcium phosphate, carbon black, coal, coal fines, calcite, quartz, and any combination thereof.

The binder composition may be added to the raw materials to form a mixture. The binder composition may be, for example, an aqueous composition or solution, and it may include, for example, a metal salt and/or a modified starch. The modified starch may be, for example, a cationic modified starch, a polycationic modified starch, and/or an amphoteric starch with a net positive or a net negative charge. Non-limiting, illustrative examples of modified starches include 2-hydroxy-3-(dimethylamino) propyl ether methyl chloride quaternary salt, methyl cellulose, sodium phosphate, potassium phosphate, sodium octenyl succinate, acetylated distarch adipate, oxidized starch, phosphated distarch phosphate, and any combination thereof.

When a binder composition comprises a modified starch, the amount of modified starch in the composition is not particularly limited. For example, a binder composition may include from about 1 wt. % to about 99 wt. % of the modified starch, such as from about 1 wt. % to about 90 wt. %, about 1 wt. % to about 80 wt. %, about 1 wt. % to about 70 wt. %, about 1 wt. % to about 60 wt. %, about 1 wt. % to about 50 wt. %, about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 10 wt. %, about 10 wt. % to about 20 wt. %, about 10 wt. % to about 30 wt. %, about 10 wt. % to about 40 wt. %, about 10 wt. % to about 50 wt. %, about 10 wt. % to about 60 wt. %, about 20 wt. % to about 30 wt. %, about 20 wt. % to about 40 wt. %, or about 20 wt. % to about 50 wt. %.

In certain embodiments, the binder composition may comprise a modified starch, such as 2-hydroxy-3-(dimethylamino) propyl ether methyl chloride quaternary salt, and water, such as from about 10 wt. % to about 40 wt. %, about 20 wt. % to about 30 wt. %, or about 25 wt. % of the 2-hydroxy-3-(dimethylamino) propyl ether methyl chloride quaternary salt and about 60 wt. % to about 90 wt. %, about 70 wt. % to about 80 wt. %, or about 75 wt. % of the water, although any amount of modified starch and water disclosed herein may be selected.

For example, any binder composition disclosed herein may comprise from about 1 wt. % to about 99 wt. % of water, such as from about 10 wt. % to about 99 wt. %, about 20 wt. % to about 99 wt. %, about 30 wt. % to about 99 wt. %, about 40 wt. % to about 99 wt. %, about 50 wt. % to about 99 wt. %, about 60 wt. % to about 99 wt. %, about 70 wt. % to about 99 wt. %, about 80 wt. % to about 99 wt. %, about 90 wt. % to about 99 wt. %, about 55 wt. % to about 95 wt. %, about 65 wt. % to about 85 wt. %, or about 70 wt. % to about 80 wt. % water.

The binder composition comprising modified starch may optionally include or exclude one or more additional components. Examples of additional components include, but are not limited to, a dispersant, a metal salt, a surfactant, a synthetic polymer, coal, coke, lime, dolomite, or any combination thereof.

Illustrative, non-limiting examples of dispersants include a polyacrylate, such as sodium polyacrylate, a polycarboxylate, polyacrylic acid, polyacrylamide, 2-acrylamido-2-methyl-1-propanesulfonic acid, and any combination thereof. Additional examples include, but are not limited to, a copolymer and/or a homopolymer comprising acrylic acid, a copolymer and/or a homopolymer comprising acetic acid, a copolymer and/or a homopolymer comprising lactic acid, a copolymer and/or a homopolymer comprising maleic acid, a copolymer and/or a homopolymer comprising sulfonic acid, a salt thereof, or any combination thereof.

Illustrative, non-limiting examples of metal salts include magnesium salts, such as magnesium acetate and/or magnesium nitrate, and copper salts, such as copper acetate and/or copper nitrate. In some embodiments, the metal salt is selected from the group consisting of a magnesium salt, a copper salt, a sodium salt, a potassium salt, an ammonium salt, and any combination thereof.

Illustrative, non-limiting examples of synthetic polymers include a homopolymer or a copolymer comprising acrylic acid, maleic acid, sulfonic acid, or a salt of any of the foregoing acids.

The optional surfactant component is not particularly limited and may be selected from, for example, an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant.

Illustrative, non-limiting examples of surfactants include alkyl aryl sulfonates, olefin sulfonates, paraffin sulfonates, alcohol sulfates, alcohol ether sulfates, alkyl carboxylates and alkyl ether carboxylates, alkyl and ethoxylated alkyl phosphate esters, and mono- and dialkyl sulfosuccinates and sulfosuccinamates, alcohol alkoxylates, alkylphenol alkoxylates, block copolymers of ethylene, propylene and butylene oxides, alkyl dimethyl amine oxides, alkyl-bis(2-hydroxyethyl) amine oxides, alkyl amidopropyl dimethyl amine oxides, alkylamidopropyl-bis(2-hydroxyethyl) amine oxides, alkyl polyglucosides, polyalkoxylated glycerides, sorbitan esters and polyalkoxylated sorbitan esters, and alkoxyl polyethylene glycol esters and diesters, betaines, sultanes, alkyl amphoacetates and amphodiacetates, alkyl amphopropionates and amphodipropionates, alkyliminodipropionate, and any combination thereof.

In some embodiments, the surfactant is selected from the group consisting of an alkyl ether carboxylate, an alkyl sulfate, an alkyl ether sulfate, an alkylbenzene sulfonate, a dialkyl sulfosuccinate, an alkyl phosphate, an ethoxylated linear alcohol, an ethoxylated alkyl phenol, a fatty acid ester, a fatty acid alcohol, an alkylpolyglucoside, an ethylene oxide/propylene oxide copolymer, a polyalcohol, an ethoxylated polyalcohol, a thiol, a fatty acid ethoxylate, and any combination thereof.

The surfactant may also be a quaternary ammonium compound and/or an amine oxide. Suitable quaternary ammonium compounds include, but are not limited to, alkyl benzyl ammonium chloride, benzyl cocoalkyl(C-C) dimethylammonium chloride, dicocoalkyl (C-C) dimethylammonium chloride, ditallow dimethylammonium chloride, di(hydrogenated tallow alkyl) dimethyl quaternary ammonium methyl chloride, methyl bis(2-hydroxyethyl cocoalkyl(C-C) quaternary ammonium chloride, dimethyl (2-ethyl) tallow ammonium methyl sulfate, n-dodecylbenzyldimethylammonium chloride, n-octadecylbenzyldimethyl ammonium chloride, n-dodecyltrimethylammonium sulfate, soya alkyltrimethylammonium chloride, and hydrogenated tallow alkyl (2-ethylhexyl) dimethyl quaternary ammonium methyl sulfate.

The amount of the additional component in the binder composition comprising modified starch is not particularly limited and may be selected from, for example, 1 wt. % to about 50 wt. %, from about 1 wt. % to about 40 wt. %, from about 1 wt. % to about 30 wt. %, from about 1 wt. % to about 20 wt. %, from about 1 wt. % to about 10 wt. %, or from about 1 wt. % to about 5 wt. %.

The binder compositions of the present disclosure that require a metal salt (and optionally include other components, such as a modified starch and/or a dispersant) may include any amount of the metal salt. For example, a binder composition may include from about 1 wt. % to about 99 wt. % of the metal salt, such as from about 1 wt. % to about 90 wt. %, about 1 wt. % to about 80 wt. %, about 1 wt. % to about 70 wt. %, about 1 wt. % to about 60 wt. %, about 1 wt. % to about 50 wt. %, about 1 wt. % to about 40 wt. %, about 1 wt. % to about 30 wt. %, about 1 wt. % to about 20 wt. %, about 1 wt. % to about 10 wt. %, about 10 wt. % to about 20 wt. %, about 10 wt. % to about 30 wt. %, about 10 wt. % to about 40 wt. %, about 10 wt. % to about 50 wt. %, about 10 wt. % to about 60 wt. %, about 20 wt. % to about 30 wt. %, about 20 wt. % to about 40 wt. %, or about 20 wt. % to about 50 wt. %.

The binder compositions including the metal salt may include or exclude other components, such as modified starch, a dispersant, a surfactant, a synthetic polymer, coal, coke, lime, dolomite, or any combination thereof.

The amount of the additional component in the binder composition comprising the metal salt is not particularly limited and may be selected from, for example, 1 wt. % to about 50 wt. %, from about 1 wt. % to about 40 wt. %, from about 1 wt. % to about 30 wt. %, from about 1 wt. % to about 20 wt. %, from about 1 wt. % to about 10 wt. %, or from about 1 wt. % to about 5 wt. %.