Process and equipment for the production of metal alloys and method for treating gases resulting from the production of metal alloys

Abstract

The present invention is intended for the field of metallurgy, in particular iron and steel metallurgy in integrated mills. In particular, the present invention discloses a process and equipment for the direct production of metal alloys with a reduced carbon content, such as steel, in a shaft furnace-type self-reduction reactor, with the aim of achieving zero net CO2 emissions. The invention also relates to agglomerate compositions containing metal oxides and carbonaceous elements suitable for the production of metal alloys such as low-carbon steel. In addition, the present invention discloses methods for recovering, treating and reusing gases generated during the production of said metal alloys.

Description

PROCESS AND EQUIPMENT FOR PRODUCTION OF METAL ALLOYS AND METHOD FOR TREATMENT OF GASES RESULTING FROM THE PRODUCTION OF METAL ALLOYS FIELD OF INVENTION

[0001] The present invention relates to the field of metallurgy, particularly iron and steelmaking in integrated plants. More specifically, the present invention relates to processes, equipment, and methods for the direct production of low-carbon metal alloys, such as steel, in a shaft furnace-type self-reduction reactor. STATE OF THE TECHNIQUE

[0002] Since ancient times, the reduction of metal oxides has been practiced by generating reducing gas and energy in the base of a shaft furnace, which then transmits this gas and energy in countercurrent to a charge column with alternating layers of ore and coke or charcoal in close contact. The center of the furnace and the crucible itself, where the molten metal will be formed, are filled with coke or charcoal (the so-called coke foot). This type of procedure results in the production of a metal with a high carbon content. In the case of iron alloys, this intermediate metal is called pig iron, which must undergo various treatments in steel mills before being transformed into steel.

[0003] This method is called gas / solid mode, referring to the fact that the reduction process is based on the interaction of successive solid layers of ore and coke or charcoal, carried from the top, permeated by reducing gas generated at the base and which rises in a countercurrent until it exits at the top. This mode is how blast furnaces are operated today. which use a column of coke (also known as a “coke foot”) supported at the bottom of the furnace and filling the entire crucible at the base of the furnace and which serves both to support the load and to generate energy and gas for the process, by injecting heated air, also having the mission of ensuring the distribution of gas throughout the volume of the blast furnace.

[0004] Due to the arrangement of the coke foot as described, the molten metal necessarily passes through and mixes with the coke or charcoal, absorbing carbon until it reaches saturation, when it reaches the crucible at the bottom of the furnace. This carbon absorption, in the case of iron, requires a subsequent step carried out in the steel mills, where this excess carbon and other contaminants are removed from the metal to obtain the final steel. These carbon reduction and conversion treatments of pig iron into steel, carried out in so-called converter steel mills, result in significant increases in the capital and operating costs of the process.

[0005] In addition to the above problem, current processes conducted in blast furnaces suffer from low energy efficiency, long duration of approximately 8 hours of residence time from the top to the bottom of the column for metal reduction, which implies large blast furnaces, between 20 m and 25 m in loading height, diameters of up to 14 m, and high carbon footprints.

[0006] Given the numerous problems with the current state of the art, which are incompatible with current climate action goals, the lack of more efficient solutions from an energy and economic point of view becomes evident, while allowing for the radical elimination of the fossil carbon footprint, through biomass coal and green energy. OBJECTIVES OF THE INVENTION

[0007] The present invention aims to disclose a process and equipment for direct production of metal alloys with reduced carbon content, such as steel, in a shaft furnace type self-reduction reactor, aiming at zero net CO2 emissions.

[0008] The present invention has as a second objective to reveal compositions of agglomerates containing metal oxides and carbonaceous elements suitable for the production of metal alloys such as low carbon steel.

[0009] Furthermore, the present invention aims to reveal a method of recovery, treatment and reuse of gases generated during the production of said metal alloys. SUMMARY OF THE INVENTION

[0010] The present invention discloses a process that enables the direct production of low-carbon metal alloys in a shaft-furnace self-reduction reactor with reduced need for post-treatment, significantly reducing capital and operating production costs. These results stem from the use of metal oxide agglomerates with carbon elements responsible for their reduction, dosed in appropriate proportions. These reduction processes depend solely on the energy supply, resulting in a significant reduction in processing time in this reduction mode—20 to 30 minutes, compared to 8 hours in the current mode, which requires the slow penetration of reducing gas and energy into each particle of the charge. This difference results in a charge column only 1 to 2 meters high in the shaft-furnace self-reduction reactor, eliminating the need for a coke base, either as a supporting element or as a power source.Additionally, molten metal collects in a crucible now free of elements. carbonaceous and the final carbon content can be easily adjusted by injecting, if and when necessary, O2 via lances.

[0011] In addition to the metal alloy production process, the present invention also discloses equipment with suitable configurations for this purpose. Agglomerates and their compositions are also described, as well as methods for optimizing the energy and environmental aspects of the process through the capture and reuse of the resulting gases.

[0012] The production process according to the proposed invention is based on the calculated carbon dosage in the agglomerate charge to produce metal in the typical carbon range of steels. The reduction is carried out in a shaft furnace-type self-reduction reactor, without coke or coal, and equipped with O2 lances for possible composition adjustments. The cast metal will be the same as that currently produced in LD / BOF converters, with only final adjustments planned in ladle furnaces or degassing units, as is current practice.

[0013] Since there is no coke or coal column inside the shaft furnace type self-reduction reactor, the energy generation for the process is done by different generation and injection alternatives in the shaft furnace type self-reduction reactor that will give rise to the different operating modes of the present invention.

[0014] A notable feature of self-reduction is that because it is possible to dose the carbon added to the self-reducing clusters, it is possible to decide the carbon content of the metal produced.

[0015] According to one embodiment of the invention, it relates to equipment for producing metal alloys specially adapted to produce metal alloys using agglomerates comprising a mixture of metal oxides and carbonaceous elements, said The equipment has means to inject energy into the base of the shaft furnace type self-reduction reactor in the agglomerate loading column without the need for a coke column and is also equipped with means to inject O2 into the metal contained in the crucible for fine adjustment of composition.

[0016] The present invention discloses an equipment for producing metal alloys, comprising: at least one shaft furnace type self-reduction reactor comprising at least one agglomerate charging column, at least one gas collector, at least one crucible and at least one fuel burner.

[0017] The pellet feed column comprises a mixture of metal oxides and carbonaceous elements and the fuel burner injects energy into the shaft furnace type self-reduction reactor through fuel combustion.

[0018] The fuel burner burns reformed gases from the overhead gas of the shaft furnace type self-reduction reactor itself.

[0019] Carbonaceous elements comprise in their composition at least one of: mineral coal fines, thermal coals, metallurgical coals or biocarbon of vegetable or animal origin.

[0020] The burners are arranged along the circumference of the lower section in several planes.

[0021] The fuel burner is enriched with up to 100% O2.

[0022] The fuel burner is of the torch type and the energy source is one of the following: pulverized thermal coal, pulverized biocarbon (biotoast), natural gas or biogas.

[0023] The agglomerate loading column is between 1 and 2 m high.

[0024] The shaft furnace type self-reduction reactor comprises at least one O2 injection lance connected to the crucible configured to inject O2 directly into the crucible.

[0025] The crucible comprises a siphon system configured to continuously drain the molten metal separately from the slag, and the slag, which accumulates in the supernatant portion of the molten material in the crucible, is continuously removed through collection channels in the upper portion of the crucible.

[0026] The present invention discloses a method of treating gases resulting from the production of metal alloys in equipment for the production of metal alloys, as described above, which comprises at least the following steps: a) collecting gaseous by-products in the upper portion of the shaft furnace type auto-reduction reactor through the gas collector; b) subjecting the gaseous by-products to treatment steps; and c) redirecting the treated by-product to be reused in the generation of energy of the shaft furnace type auto-reduction reactor.

[0027] Step b) comprises at least one fines removal step.

[0028] Step b) comprises at least one water recovery step by condensation.

[0029] The method of treating gases resulting from the production of metal alloys involves at least one stage of selective CO2 removal, with a portion of the CO2 being redirected to adiabatic flame temperature calibration (TAC) and the remainder being redirected to selective CO2 capture.

[0030] Adiabatic flame temperature calibration (AFT) involves the use of CO2 remaining after selective removal in a mixture with O2 to control the adiabatic flame temperature (TAC) of the combustion in the shaft furnace type self-reduction reactor.

[0031] Between 35% and 100% of the collected gaseous byproducts are converted into recycled top gas for reuse in the power generation of the shaft furnace type self-reduction reactor.

[0032] According to another aspect of the present invention, it refers to a process for producing metal alloys that uses agglomerates comprising a mixture of metal oxides and carbonaceous elements, the carbonaceous elements comprising in their composition, among others: fines of mineral coal, thermal coal, metallurgical coal or biocarbon of vegetable or animal origin, pure or in mixture in any proportions.

[0033] The referred process comprises the generation of energy for injection into the shaft furnace type self-reduction reactor produced by at least one of the following methods: burning by air, heated or not, enriched by O2 or not, of fossil fuel or biomass, solid, liquid or gaseous or their mixtures in any proportion; or burning by O2 of recycled process gas, with selective removal of CO2 and using as a flame temperature moderating element, CO2 in a mixture with O2 oxidizer in place of N2, excluded from the process by the use of O2 in place of air.

[0034] The metal alloy production process comprises the following steps: a) manufacturing of agglomerates of metal oxides and carbonaceous elements; and b) production of steel using agglomerates of metal oxides and carbonaceous elements.

[0035] In step b), the fuel burner injects energy into the shaft furnace type self-reduction reactor by burning fuel and metal alloys are produced with a carbon content ranging from 0.05% to 2.00%.

[0036] Step a) comprises the addition in a mixer of at least one binding agent in a proportion of 1% to 5% by mass, biocarbon in a proportion of 15% to 25% by mass, iron ore in a proportion of 60% to 75% by mass and slag-forming agents in a proportion of 7% to 10% by mass.

[0037] Step b) involves the use of a column of agglomerate loading comprising an agglomerate of metal oxides and carbonaceous elements, with the carbonaceous elements comprising in their composition at least: fines of mineral coal, thermal coal, metallurgical coal or biocarbon of vegetable or animal origin.

[0038] Step b) involves the injection of O2. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The present application presents figures to illustrate possible non-limiting configurations of the present invention.

[0040] Figure 1 illustrates a shaft furnace type self-reduction reactor configured for operation using external fuel air-fired power generation.

[0041] Figure 2 illustrates a shaft furnace type self-reduction reactor configured for operation using external fuel air-fired power generation, equipped with a side O2 injection lance.

[0042] Figure 3 illustrates a shaft furnace type self-reduction reactor configured for operation using external fuel combustion power generation, equipped with a central O2 injection lance.

[0043] Figure 4 illustrates a shaft furnace type self-reduction reactor configured for operation using power generation by O2 combustion of recycled process gas after particulate cleaning and selective removal of CO2 and H2O and using CO2 as the neutral element to control the flame temperature in place of N2 excluded from the process because it is combustion by O2 and not by air.

[0044] Figure 5 illustrates a flowchart describing a configuration of the manufacturing process of the agglomerate briquettes used in the shaft furnace type self-reduction reactor.

[0045] Figure 6 illustrates a flowchart describing a steel production process configuration using agglomerates and O2 injection.

[0046] The reference numbers used in this application are: 1 - shaft furnace type self-reduction reactor; 2 - agglomerate charging column; 3 - molten metal outlet by siphon; 4 - crucible; 5 - fuel burner; 6 - high pressure ring / torus; 7 - collecting channels; 8 - gas collector; 9 - oxygen injection lance; 10 - injector end; 11 - burners; 12 - blower; 13 - heaters. DETAILED DESCRIPTION OF THE INVENTION

[0047] Before the invention is described in detail, it should be understood that it is not limited to the specific component parts of the apparatus described, as such components may vary. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. It should be noted that, as used in the specification and appended claims, the singular forms "a," "an," "0," and "a" include singular and / or plural referents, unless the context clearly indicates otherwise. Furthermore, it should be understood that, in the case of parameter ranges bounded by numerical values ​​are provided, the ranges are considered to include these limiting values.

[0048] It should also be understood that the embodiments disclosed herein should not be construed as individual embodiments that are not related to each other. Features discussed in connection with one embodiment should also be disclosed in connection with other embodiments shown herein. If, in a case, a specific feature is not disclosed in connection with one embodiment but with another, the skilled artisan would understand that this does not necessarily mean that the feature is not intended to be disclosed in connection with the other embodiment. The skilled artisan would understand that the essence of this application is to also disclose the feature in connection with the other embodiment, but that for the sake of clarity and to keep this specification to a manageable volume, this has not been done.

[0049] According to a first aspect, the present invention relates to a shaft furnace-type equipment specially adapted for the production of metal alloys using agglomerates comprising metal oxides and carbonaceous elements for their reduction. The present invention discloses a metal alloy production equipment, comprising: at least one shaft furnace-type self-reduction reactor 1 comprising at least one agglomerate charging column 2, at least one gas collector 8, at least one crucible 4, and at least one fuel burner 5.

[0050] The pellet feed column 2 comprises a mixture of metal oxides and carbonaceous elements and the fuel burner 5 injects energy into the shaft furnace type self-reduction reactor 1 through fuel combustion.

[0051] According to one configuration of the present invention, the furnace is of the shaft furnace type with a circular cross-section or any other, but with reduced dimensions in relation to the blast furnaces commonly used in the production of metal alloys by the gas / solid mode.

[0052] In a preferred configuration, the shaft furnace type self-reduction reactor 1 of the present invention preferably has a column of agglomerate charge 2 between 1 and 2 meters in height.

[0053] In a second configuration, the agglomerate loading column 2 is between 1 and 4 m high.

[0054] Depending on the energy generation modality to be applied, the shaft furnace type self-reduction reactor 1 of the present invention may present different configurations specially adapted to the mode in question.

[0055] According to a preferred configuration, the shaft furnace self-reduction reactor 1 is adapted for power generation by burning fuel. In this configuration, the shaft furnace self-reduction reactor 1 is equipped with burners in its lower section, preferably arranged along the circumference of the lower section or in a line, on the same plane or on different planes.

[0056] This route generates energy by burning natural gas, biogas, thermal coal, biotoast or pulverized biochar, pure or in mixtures in any proportion, using burners 11, burning with heated air, or not, enriched in O2, or not.

[0057] Since the objective is to generate only energy and not energy and reducing gas, as is the case with blast furnaces, the combustion is calibrated to produce 100% CO2+ H2O.

[0058] The top gas will incorporate, in addition to N2 + CO2 + H2O from the combustion of fuels, CO and C n H mfrom the reduction reactions and volatiles of the load. After cleaning and recycling the fines and recovering the water by condensation, the top gas will be used to generate heated air and electricity in conventional circuits.

[0059] By eliminating the use of coke and sinter, typical of blast furnaces, eliminating coke ovens and hot sintering, and eliminating the use of coke foot or coal briquettes, this invention allows for a zero carbon footprint when using energy and carbon reducers from biomass. Even using 100% fossil fuels and reducers, a 15% to 25% reduction in the carbon footprint of steel production is feasible.

[0060] If the reducing coal contained in the agglomerates and the fuel burned for power generation is of organic origin (animal or plant), the steel, gas, and electricity will qualify as green (non-fossil fuel). Thus, this invention allows the production of Net-Zero CO2 Emission Steel plus green gas and electricity credits.

[0061] Because it is feasible to use mixtures of reducers and fuels, in any proportion, the progressive conversion of the process to the production of Net-Zero Steel can be done economically as supply chains appropriate to the steelmaking scale are promoted and consolidated.

[0062] According to the present invention, the shaft furnace type self-reduction reactor 1 also has a gas collector 8 in its upper portion configured to collect the gaseous by-product generated during the agglomerate fusion reduction process.

[0063] Additionally, the shaft furnace type self-reduction reactor 1 comprises a crucible 4 in its lower portion configured to receive the molten material resulting from the reduction and melting of the agglomerates. Crucible 4 is equipped with a siphon system for the continuous flow of the molten metal separately from the slag. The slag, which accumulates in the supernatant portion of the molten material in crucible 4 due to its lower density, is continuously removed through collection channels 7 in the upper portion of crucible 4.

[0064] According to a preferred embodiment of the present invention, the shaft furnace type self-reduction reactor 1 is provided with oxygen injection lances 9 with an injector end 10 located in the crucible 4, so as to allow direct supply of O2 to the molten metal accumulated therein. The volume of O2 injected by the oxygen injection lances 9 can be controlled in order to adjust the carbon content of the molten metal to desired ranges, for example, adjusted to the typical ranges of steels.

[0065] Crucible 4 is equipped with a siphon system for the continuous flow of the molten metal separately from the slag, and the slag, which accumulates in the supernatant portion of the molten material in crucible 4, due to its lower density, is continuously removed through collection channels 7 in the upper portion of crucible 4.

[0066] The fuel burner 5 of the equipment for producing metal alloys is of the blowtorch type and the energy source is one of the following: pulverized thermal coal, pulverized biocarbon (biotoast), natural gas or biogas.

[0067] In a preferred configuration, the fuel burner 5 burns reformed gases from the overhead gas of the shaft furnace autoreduction reactor 1 itself.

[0068] Preferably, the fuel burner 5 is enriched with up to 100% O2.

[0069] In a second configuration, the reformed gases from the top gas of the shaft furnace type autoreduction reactor 1 itself are intended for other applications and are not reused in the shaft furnace type autoreduction reactor 1.

[0070] Carbonaceous elements comprise in their composition at least one of: mineral coal fines, thermal coals, metallurgical coals or biocarbon of vegetable or animal origin.

[0071] According to a second aspect, the present invention discloses a method for treating gaseous by-products collected in the upper portion of the shaft furnace type auto-reduction reactor 1. The method for treating gases resulting from the production of metal alloys comprises at least the following steps: a) collecting gaseous by-products in the upper portion of the shaft furnace type auto-reduction reactor 1 through the gas collector 8; b) subjecting the gaseous by-products to treatment steps; and c) redirecting the treated by-product to be reused in the generation of energy of the shaft furnace type auto-reduction reactor 1.

[0072] After the gases are captured, they may undergo some treatment steps to reuse them for energy generation in the shaft furnace type self-reduction reactor 1, or for use in electricity generation or heating.

[0073] Suitable treatments for reusing collected gases include the removal of fines, the removal of H2O by condensation and the selective removal of CO2.

[0074] According to the present invention, the selectively removed CO2 is used, according to a calculated proportion, in the calibration of the adiabatic flame temperature (TAC), and the remainder of the selectively captured CO2 may be destined for storage (CCS) or use according to alternative circular carbon pathways (CCUS).

[0075] Between 35% and 100% of the collected gaseous by-products are converted into recycled top gas for reuse in the power generation of the shaft furnace type self-reduction reactor 1 .

[0076] The present invention produces, depending on the volatile content of the reducer used, gases with high contained energy, even higher than the energy demand of the process.

[0077] It is concluded that the gas produced in the reduction has sufficient energy to cover the process demand, with small adjustments being possible by selecting reducers with adequate volatile contents.

[0078] Therefore, it becomes possible to recycle the top gas for use as fuel in the process, provided that N2 is eliminated from the combustion in favor of combustion with O2, and the present invention adopts CO2 as an inert element in place of N2 in moderating the adiabatic flame temperature (AFT).

[0079] This process configuration involves the adoption of a wet cleaning circuit for the top gas, with collection of fines from the load, to be fully recycled, and recovery, by condensation, of the water (H2O) from the burning of the Cn H m , present in the reducer volatiles, followed by a selective CO2 absorption system using one of the available industrial methods (Benfield, Amina, PSA, etc.).

[0080] Therefore, water (H2O) is a byproduct of the process in addition to the CO2 that will be available for circular use (CCUS) or safe storage (CCS) or both.

[0081] Recycled fuel gas will have CO + CO2 + C n H m of the reduction reactions plus CO + C n H m of the volatiles of the reducers. To this mixture will be added an appropriate proportion of CO2, dosed to control the flame temperature.

[0082] All the modes described above admit mixed or combined versions.

[0083] According to a third aspect, the present invention discloses a process for producing metal alloys comprising low carbon contents aiming at zero net CO2 emissions.

[0084] One of the main aspects of this process is the use of clusters of metal oxides and carbonaceous elements (or simply “clusters”).

[0085] The metal alloy production process comprises at least the following steps: a) manufacturing of agglomerates of metal oxides and carbonaceous elements; and b) production of steel using agglomerates of metal oxides and carbonaceous elements.

[0086] In step b), the fuel burner 5 injects energy into the shaft furnace type self-reduction reactor 1 and metal alloys with a carbon content in the range of 0.05% to 2.00% are produced.

[0087] Step a) comprises the addition in a mixer of at least one binding agent in a proportion of 1% to 5% by mass, biocarbon in a proportion of 15% to 25% by mass, iron ore in a proportion of 60% to 75% by mass and slag-forming agents in a proportion of 7% to 10% by mass.

[0088] Step b) comprises the use of an agglomerate loading column 2 comprising an agglomerate of metal oxides and carbonaceous elements, the carbonaceous elements comprising in their composition at least: mineral coal fines, thermal coals, metallurgical coals or biocarbon of vegetable or animal origin.

[0089] Preferably, step b) also comprises the injection of O2.

[0090] According to a preferred embodiment of the present invention, the agglomerates comprise a mixture of metal oxides and carbonaceous elements in a proportion calculated to produce metals with a desired carbon content. In the case of producing iron alloys, it is desirable that the final metal alloy have, for example, a carbon content in the range of steel. The ratio between the two components must also take into account that the amount of carbonaceous element must be sufficient to promote the reduction and fusion of the metal oxides.

[0091] The agglomerates of the present invention can be produced in various formats, including briquettes, pellets, or any other format deemed appropriate by a person skilled in the art for a specific application. Additionally, these agglomerates can be obtained by cold curing, which significantly reduces production costs.

[0092] According to a preferred embodiment of the present invention, the metal oxide of the agglomerate is iron oxide.

[0093] Alternatively, the metal oxide of the cluster consists of oxides of other metals or a mixture of these, with or without iron oxide.

[0094] Preferably, the carbonaceous elements of the agglomerate comprise at least one of the following ingredients: coal fines, preferably fines used in PCI (pulverized coal injection) or, alternatively, fines of other coals; coals for thermal or metallurgical use; or biocarbons of plant or animal origin (e.g., biocarbon from agricultural and urban forestry residues). Alternatively, the carbonaceous elements of the agglomerate comprise a mixture of the aforementioned ingredients.

[0095] In addition to metal oxides and carbonaceous elements, agglomerates may comprise other ingredients such as ash fluxing elements, gangue, slag, and organic and inorganic binders.

[0096] According to the metal alloy production process of the present invention, the agglomerates are continuously added into the shaft furnace-type autoreduction reactor 1, preferably through the upper portion of the furnace. Once inside the shaft furnace-type autoreduction reactor 1, the agglomerates descend with the progressive melting of the agglomerate charge column 2 to high temperatures suitable for reducing the oxides and maintaining the liquid metal in the crucible 4. In general, the total residence time from the charge at the top to melting at the base of the shaft furnace-type autoreduction reactor 1, the agglomerate reduction and melting process takes approximately 20 min.

[0097] The generation of energy required to carry out the process of the present invention can be preferably carried out through the combustion of fuel.

[0098] In the fuel combustion energy generation modality, a plurality of energy sources can be used, including: pulverized thermal coal, pulverized biocarbon (biotoast), natural gas and biogas.

[0099] Within the scope of the present invention, it is conceivable that the generation of energy by combustion uses any combination of fuels in solid, liquid and gaseous state, in varying purity levels.

[0100] According to one embodiment of the present invention, the gas or gaseous component of the burning fuel may be heated or enriched with O2, potentially up to 100% O2.

[0101] According to a preferred configuration of the present invention, the energy is generated by burning gas from the capture of gas produced by the shaft furnace type self-reduction reactor itself during the metal alloy production process.

[0102] As the metal melts at the base of the agglomerate feed column 2 of the shaft furnace autoreduction reactor 1, the metal flows to the lower portion of the same, depositing in crucible 4. Once in crucible 4, the molten material spontaneously separates into slag and liquid metal due to the difference in density. Crucible 4 at the bottom of the shaft furnace autoreduction reactor 1 is configured to allow the separation of these two portions, directing the slag supernatant and the molten metal bottom to separate leakage routes. This collection and separation of the molten material occurs continuously, without the need to interrupt the operation of the shaft furnace autoreduction reactor 1.

[0103] Once the molten material reaches crucible 4, the metal can have its carbon content reduced by injecting O2 directly into crucible 4. This injection is carried out using an oxygen injection lance 9, either lateral or central, installed in the shaft furnace type self-reduction reactor 1 itself.

[0104] Simultaneously with the collection of the molten material, the gaseous byproducts generated during the fusion-reduction process are collected. These gases are collected in the upper portion of the shaft furnace autoreduction reactor 1 and can be directed to subsequent treatment, either for reuse in the generation of energy for the shaft furnace autoreduction reactor 1 or for other purposes.

[0105] The present invention combines the appropriate dosage of reducing carbon in the agglomerates, the elimination of the presence of coke in the crucible 4 of the shaft furnace type self-reduction reactor 1 and the final adjustment feature of the oxygen injection lances 9, so as to allow the continuous casting of a metal with carbon content in the steel range, without passing through the intermediate pig iron product.

[0106] From the above fact it follows that the present invention dispenses with the production of intermediate metal, pig iron in the case of iron reduction, in converter steel mills, the metal being produced in the self-reduction reactor type shaft furnace 1 already in the typical composition range of steels, and can be directly directed, as is currently common practice, to the finishing and composition and temperature adjustment sections in ladle or deoxidation furnaces before continuous casting.

[0107] The present invention presents clear advantages in relation to state-of-the-art solutions, among which the following deserve to be highlighted: greater energy efficiency; the reduction or elimination of the environmental footprint; carbon; reduced operating costs through increased energy efficiency and the possibility of using lower-value raw materials; reduced capital costs for integrated plants through the elimination of coking, sintering, and LD / BOF steelmaking; and the replacement of fossil carbon with biocarbon from agricultural and urban forestry residues. All of these benefits make Net-Zero CO2 Emission Steel or even negative-emission steel economically viable when coupled with CCS (Carbon Capture and Storage) / CCDS (Carbon Capture, Utilization, and Storage) systems.

[0108] An example of iron ore used in the present invention - MUSA - is found in Table 1, with the respective mass percentages. Table 1 - composition of an example of iron ore (MUSA).

[0109] An example of the composition of the raw material found in a type of biochar used in the present invention - bagasse biochar - is found in Table 2, with the respective mass percentages. Table 2 - composition of an example of biochar.

[0110] An example of the composition of the binder used - hydrated lime - is found in Table 3, with the respective mass percentages. Table 3 - composition of an example of a binder.

[0111] An example of a flux - furnace slag - is found in Table 4, with the respective mass percentages. Table 4 - composition of an example of flux.

[0112] An example of the composition of fines is found in Table 5, with the respective mass percentages. Table 5 - composition of an example of fine returns.

[0113] An example of the composition of gases is found in Table 6, with the respective mass percentages. Table 6 - composition of an example of gas returns.

[0114] An example of the composition of the process slag is found in Table 7, with the respective mass percentages. Table 7 - example of slag composition.

[0115] An example of the composition of the metal (steel) resulting from the process is found in Table 8, with the respective mass percentages. Table 8 - example of metal composition (steel).

[0116] Compared to traditional blast furnaces, the shaft furnace self-reduction reactor 1 of the present invention does not have the high charge column characteristic of blast furnaces, which rests on the bottom of the crucible. The metal produced in the blast furnaces is contaminated with carbon from the coke base until it reaches saturation (approximately 4.5% carbon). In the shaft furnace self-reduction reactor 1, it is possible to produce metal alloys in the steel range (0.1-1.0% carbon) directly in the reduction reactor without the coke column or briquettes, so that the metal in the crucible is free of carbon saturation, making it possible to dispense with steel mills, which are primarily dedicated to reducing the carbon content of the metal, typical of blast furnace pig iron, which is saturated with carbon at approximately 4.5% carbon, to the steel composition ranges as previously defined.

[0117] It should be noted that the drawings presented are not necessarily to scale and are merely conceptual in nature. Nevertheless, it is expressly provided that all combinations of elements that perform the same function in substantially the same manner to achieve the same results as the elements claimed herein are within the scope of the present invention. Finally, it should be noted that the scope of protection of the present invention encompasses other possible variations and is not limited solely by the content of the claims alone, including possible equivalents.

Claims

CLAIMS 1. Equipment for producing metal alloys, characterized by the fact that it comprises: at least one shaft furnace type self-reduction reactor (1) comprising at least one agglomerate charging column (2), at least one gas collector (8), at least one crucible (4) and at least one fuel burner (5); wherein the agglomerate charging column (2) comprises a mixture of metal oxides and carbonaceous elements; and wherein the fuel burner (5) injects energy into the shaft furnace type self-reduction reactor (1) through the combustion of fuel.

2. Equipment for producing metal alloys, according to claim 1, characterized by the fact that the fuel burner (5) is of the blowtorch type; and the energy source is one of the following: pulverized thermal coal, pulverized biocarbon (biotoast), natural gas or biogas.

3. Equipment for producing metal alloys, according to claim 1, characterized by the fact that the carbonaceous elements comprise in their composition at least one of: mineral coal fines, thermal coals, metallurgical coals or biocarbon of vegetable or animal origin.

4. Equipment for producing metal alloys, according to claim 2, characterized in that the burners are arranged along the circumference of the lower section in one or more planes.

5. Equipment for producing metal alloys, according to claim 2, characterized by the fact that the fuel burner (5) is enriched with up to 100% O2.

6. Equipment for producing metal alloys, according to claim 2, characterized by the fact that the fuel burner (5) burns reformed gases coming from the top gas of the shaft furnace type self-reduction reactor (1) itself.

7. Equipment for producing metal alloys, according to claim 1, characterized in that the agglomerate loading column (2) is between 1 and 2 m in height.

8. Equipment for producing metal alloys, according to claim 1, characterized by the fact that the shaft furnace type self-reduction reactor (1) comprises at least one O2 injection lance (9) connected to the crucible (4) configured to inject O2 directly into the crucible (4).

9. Equipment for producing metal alloys, according to claim 1, characterized in that the crucible (4) comprises a siphon system configured to continuously drain the molten metal separately from the slag; and in that the slag, which accumulates in the supernatant portion of the molten material in the crucible (4), is continuously removed through collection channels (7) in the upper portion of the crucible (4).

10. Method of treating gases resulting from the production of metal alloys in equipment for producing metal alloys, as defined by claim 1, characterized by the fact that it comprises the following steps: a) collecting gaseous by-products in the upper portion of the shaft furnace type self-reduction reactor (1) through the gas collector (8); b) subjecting the gaseous by-products to treatment steps; and c) redirecting the treated by-product to be reused in the generation of energy of the shaft furnace type self-reduction reactor (1).

11. Method of treating gases resulting from the production of metal alloys, according to claim 10, characterized in that step b) comprises at least one fines removal step.

12. Method of treating gases resulting from the production of metal alloys, according to claim 10, characterized in that step b) comprises at least one step of recovering water by condensation.

13. Method of treating gases resulting from the production of metal alloys, according to claim 10, characterized by the fact that it involves at least one step of selective removal of CO2; and wherein, a part of the CO2 is redirected to the adiabatic flame temperature calibration (TAC) and the remainder is redirected to the selective capture of CO2.

14. Method of treating gases resulting from the production of metal alloys, according to claim 13, characterized by the fact that the calibration of the adiabatic flame temperature (TAC) involves the use of CO2, remaining after selective removal, in a mixture with O2 to control the adiabatic flame temperature (TAC) of the burning in the shaft furnace type self-reduction reactor (1).

15. Method of treating gases resulting from the production of metal alloys, according to claim 10, characterized by the fact that between 35% and 100% of the collected gaseous by-products are converted into recycled top gas to be reused in the generation of energy in the shaft furnace type self-reduction reactor (1).

16. Process for producing metal alloys characterized by the fact that it comprises the following steps: a) manufacturing of agglomerates of metal oxides and carbonaceous elements; b) production of steel using agglomerates of metal oxides and carbonaceous elements; and in step b), the fuel burner (5) injects energy into the shaft furnace type self-reduction reactor (1) through the combustion of fuel; and metal alloys with a carbon content ranging from 0.05% to 2.00% are produced.

17. Process for producing metal alloys, according to claim 16, characterized in that step a) comprises the addition in a mixer of at least one binding agent in a proportion of 1% to 5% by mass, biocarbon in a proportion of 15% to 25% by mass, iron ore in a proportion of 60% to 75% by mass and slag-forming agents in a proportion of 7% to 10% by mass.

18. Process for producing metal alloys, according to claim 16, characterized in that step b) comprises the use of a column of agglomerate charge (2) comprising an agglomerate of metal oxides and carbonaceous elements; and the carbonaceous elements comprise in their composition at least: fines of mineral coal, thermal coal, metallurgical coal or biocarbon of vegetable or animal origin.

19. Process for producing metal alloys, according to claim 16, characterized in that step b) comprises the injection of O2.

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