RU2783389C2 - Solid agglomerated product based on iron oxides and its production method - Google Patents

Abstract

FIELD: metallurgy.

SUBSTANCE: invention relates to the production of a solid agglomerated product for use as charge material for an electric-arc furnace. The product contains at least one fraction (M, M1, M2, M3) of a side product of a steelmaking process, having the first part containing iron oxide (II) (FeO), and the second part containing iron oxide (III) (Fe₂O₃), a solid fuel fraction (CR) containing carbon (C_fix), and at least one inorganic binder for agglomeration and giving the resulting product mechanical characteristics providing storage and transportation. The inorganic binder at least partially contains slag, while the mentioned slag is white slag and/or black slag, wherein white slag is waste of secondary metallurgy processes, and black slag is waste of a process of melting in the electric-arc furnace.

EFFECT: simplification of transportation, storage of a product, reduction in waste, and optimization of resources.

13 cl, 2 dwg, 1 tbl

Description

The field of technology to which the invention belongs

The present invention relates to solid agglomerated products based on iron oxides and to methods for their production.

The agglomerated products according to the invention can be used in particular in electric arc furnaces to recover their iron content.

Prerequisites for the creation of the invention

In the steel industry, various by-products of iron processing and steel production are known and are generally considered industrial waste.

These by-products mainly contain iron oxides as well as other waste products.

For example, these iron processing wastes can be fines from iron oxide granulation plants, flue dust, dust and fines from steel mills, mill scale, fines from direct iron plants.

These by-products can be divided into the following two large groups according to their size:

- fines with particle sizes less than 100 µm, usually characterized as dust and usually captured by dedusting systems, and

- coarse fraction with particle sizes from 100 microns to 8 mm.

Generally, these by-products are considered to be waste from steel mills and mining operations and should be treated as waste with high operating costs.

Another disadvantage is the laboriousness of collecting, transporting and moving these by-products due to the small particle size.

In addition, the presence of these by-products in large quantities is associated with significant losses in the output of the steel plant due to their high iron content.

Methods and devices are also known for collecting by-products from metallurgical plants, which make it possible, starting with the iron-based by-products mentioned above, and when mixed with a reducing agent, and possibly other additives or by-products, produce agglomerated products such as pellets and/or briquettes that are easier to handle and easier to transport and move.

In these agglomerated products, when subjected to certain temperatures and certain other factors, reduction reactions can occur in which iron oxides are reduced to metallic iron, which can be collected.

Typically, these agglomerated products are fed to iron production reactors such as blast furnaces or direct iron plants.

For example, JP 2008095177 A and US 2004/025633 describe an agglomerated product obtained by agglomerating ferrous metal and carbon with a hydraulic binder, i.e. cement used in blast furnaces.

Also known is patent document EP 0976843, which describes a method for cold preparation of briquettes based on carbon and iron oxides without the use of an alkaline binder.

However, these methods are not very efficient and do not guarantee efficient recovery of metallic iron from the iron oxides contained in these by-products when used as charge material for conventional electric arc furnaces.

In addition, these processes typically use carbon in a substantially stoichiometric or somewhat higher relative amount, which runs the risk of removing carbon from the conventional melting process that takes place in an electric arc furnace.

In addition, these agglomerated products, usually containing a single hydraulic binder such as cement or quicklime, do not have high mechanical characteristics that would allow them to be used effectively in an electric arc furnace.

One of the objectives of the present invention is to provide agglomerated products based on iron oxides with improved mechanical characteristics for easy handling, storage and transportation.

Yet another object of the invention is to provide an agglomerated product which can be used efficiently and in high yield as charge material for electric arc furnaces.

Another object of the invention is to collect both fine and coarse iron by-products for the production of iron oxide agglomerated products, so that their dispersion in the environment is reduced and material waste is reduced while optimizing available resources.

It is another object of the invention to provide agglomerated iron oxide products that optimize the reduction reaction with the reducing agent and then maximize the amount of metallic iron recoverable from the iron oxides present in these by-products.

The applicant has developed, tested and implemented the present invention in order to overcome the shortcomings of the prior art and achieve the above and other objects and advantages.

Brief description of the invention

The invention is set forth and characterized in independent claims. Dependent claims describe other features of the invention or embodiments of the main inventive idea.

In accordance with the above objectives, the solid agglomerated product according to the invention can be used as charge material for an electric arc furnace.

This solid agglomerated product contains the following ingredients:

- at least one fraction of a by-product of the steelmaking process, having a first part containing iron (II) oxide (FeO) and a second part containing iron (III) oxide (Fe ₂ O ₃ ),

- solid fuel fraction containing carbon C_fix, ~

- at least one inorganic binder, at least partially containing slag, for agglomerating said at least one fraction of the by-product and the solid fuel fraction with each other and imparting the required mechanical characteristics to the agglomerated product.

For the purposes of the present invention, said slag may be white slag, black slag, or a mixture of these slags in any ratio.

In one aspect of the invention, the solid fuel fraction is present in a mass amount determined by the formula CR=K*CS/C_fix, where

K is a constant number from 1.2 to 2.5,

CS is the mass amount of stoichiometric carbon, determined by the formula: CS=0.11*(Fe ²⁺ _tot)+0.16*(Fe ³⁺ _tot), where Fe ²⁺ _tot is the mass amount of iron contained in the first part, Fe ³⁺ _tot - mass amount of iron contained in the second part.

The above-described iron oxide-based solid agglomerated product can be directly used as a charge material for an electric arc furnace to recover its iron content. This product is not reintroduced into a reduction reactor or a blast furnace, a direct iron plant, or the like, as is commonly done in the prior art.

Due to the composition of the mixture, in particular the carbon content of the sintered product, it is possible to obtain a self-healing product, which, entering the electric arc furnace, is reduced to metallic iron under the influence of high temperatures, and this iron can be extracted in liquid form, thereby increasing the overall melting yield.

The solid agglomerated product based on iron oxides can also be used as a charge material for an electric arc furnace using waste metal production or for a direct iron reduction plant.

In addition, this solid agglomerated product makes it possible to recover by-products or iron fractions from various iron and steel production processes, such as waste from smoke treatment plants or direct iron reduction plants, and reuse these by-products directly on the site where they are formed.

This greatly simplifies the disposal of these by-products, which are no longer considered waste, but an additional source of iron.

In addition, the present invention relates to a method for the production of a solid agglomerated product, comprising the following steps:

- ensure the presence of at least one fraction of the by-product having a first part containing iron (II) oxide (FeO) and a second part containing iron (III) oxide (Fe ₂ O ₃ ),

- provide the presence of a solid fuel fraction containing C_fix carbon,

- to obtain a solid agglomerated product, the said at least one fraction of the by-product is mixed with the mentioned solid fuel fraction and with an inorganic binder, at least partially containing slag.

In one aspect of the invention, before mixing, the mass amount of the solid fuel fraction is determined by the formula CR=K*CS/C_fix, where

K is a constant number from 1.2 to 2.5,

CS is the mass amount of stoichiometric carbon, determined by the formula CS=0.11*(Fe ²⁺ _tot)+0.16*(Fe ³⁺ _tot), where Fe ²⁺ _tot is the mass amount of iron contained in the first part, Fe ³⁺ _tot is the mass amount of iron contained in the second part.

In addition, the present invention also relates to the use of the above-described agglomerated product as charge material for an electric arc furnace.

Brief Description of Attached Graphics

These and other features of the invention will become clear from the following description of some embodiments of the invention, to which the scope of the invention is not limited, with reference to the attached drawings (drawings).

In FIG. 1 is a block diagram of the proposed method for the production of a solid agglomerated product based on iron oxides.

In FIG. 2 is a flow diagram of the proposed method for the production of another solid sintered product based on iron oxides.

To facilitate understanding, where possible, identical reference numerals have been used throughout the drawings to designate common elements. It should be clear that the elements and features of one option can be conveniently introduced into other options without further explanation.

Description of embodiments of the invention

Various embodiments of the invention will now be described, of which one or more is illustrated in the accompanying drawings. The embodiments illustrate the invention but do not limit its scope. For example, features related to one variant can be adopted to create other variants. It should be understood that the present invention includes all such variations and modifications.

The proposed solid agglomerated product contains the following components:

- at least one fraction of a by-product, which will be referred to as M, M1, M2, M3, and which has a first part containing iron (II) oxide (FeO) and a second part containing iron (III) oxide (Fe ₂ O ₃ ),

- solid fuel fraction CR containing carbon C_fix,

- at least one inorganic binder, at least partially containing slag, for agglomerating said at least one fraction of the by-product M, M1, M2, M3 and the solid fuel fraction CR with each other and imparting the required mechanical characteristics to the agglomerated product.

Said at least one by-product fraction M, M1, M2, M3 is properly mixed with the solid fuel fraction CR to obtain the above-described agglomerated product suitable for use as a charge material for an electric arc furnace or other types of steel mills.

A solution is possible in which the solid fuel fraction is selected from the following group: anthracite, coke, fine, petroleum coke, etc.

In one aspect of the invention, the amount of carbon C_fix is the content of non-volatile, ie fixed, carbon present in the solid fuel fraction. The relative amount of carbon C_fix can be defined as the ratio of the mass of non-volatile carbon to the total mass of the fuel containing this amount of carbon.

Options are possible in which the relative amount of carbon C fix can be measured by experimentation and/or using known measurement methods.

The carbon C_fix contained in the solid fuel fraction CR acts as a reducing agent, removing oxygen from the first part containing iron (II) oxide (FeO) and the second part containing iron (III) oxide (Fe ₂ O ₃ ).

In particular, the reduction reactions of iron oxide (II) (FeO) and iron oxide (III) (Fe ₂ O ₃ ) are described by the following formulas:

2Fe ₂ O ₃ + 3C \u003d 4Fe + 3CO ₂ (g)

2FeO + C \u003d 2Fe + CO ₂ (g)

Fe ₂ O ₃ + 3C \u003d 4Fe + 3CO (g)

FeO + C \u003d Fe + CO (g)

The products of reduction reactions are metallic iron (Fe) and carbon oxides in gaseous form.

From these formulas, one can determine the mass amount of stoichiometric carbon CS required for a correct and balanced reduction reaction:

CS=(Fe ²⁺ _tot)*1/2*(PM_C/PM_Fe)+(Fe ³⁺ _tot)*3/4*(PM_C/PM_Fe),

where

Fe ²⁺ _ tot - mass amount of iron in the first part containing iron oxide (II) (FeO),

Fe ³⁺ _tot - mass amount of iron in the first part containing iron oxide (III) (Fe ₂ O ₃ ),

PM_C - atomic mass of carbon (C), equal to 12,

PM_Fe is the atomic mass of iron (Fe) equal to 55.8.

Therefore, the stoichiometric reduction reaction described above can be simplified and approximated as follows:

CS=0.11*(Fe ²⁺ _tot)+0.16*(Fe ³⁺ _tot).

In one aspect of the invention, it is provided that the solid fuel fraction CR is present in the agglomerated product in a mass amount determined by the formula CR=K*CS/C_fix, where

K is a constant number from 1.2 to 2.5, preferably from 1.3 to 1.6,

CS is the mass amount of the above stoichiometric carbon CS.

Correlating the amount of solid fuel fraction CR present in each agglomerated product makes it possible to establish a proper balance between the amount of solid fuel and the amount of iron oxides, both iron (II) oxide (FeO) and iron (III) oxide (Fe ₂ O ₃ ) . In addition, the above correlation makes it possible to determine the amount of solid fuel fraction that must be present in the sintered product in order to provide sufficient energy to maintain the kinetics of the reduction processes during the melting process in the electric arc furnace.

Therefore, the agglomerated product obtained in this way can be directly used as a charge material for an electric arc furnace, because, due to the balancing of the reducing agent and iron oxides, for the production of liquid metal, it receives part of the energy necessary for its recovery from the fuel itself.

In another embodiment, the amount of solid fuel fraction CR is less than or equal to 30 wt. % with respect to the mass of said at least one fraction of the by-product M, M1, M2, M3. This amount of solid fuel fraction CR is a good compromise between the complexity of obtaining a sintered product and the cost of its production.

In another embodiment, the amount of solid fuel fraction CR is less than or equal to 25 wt. % relative to the total weight of the solid agglomerated product.

In one embodiment, the slag may contain white slag and/or black slag.

In particular, one preferred solution is to use only white slag, since it has a higher content of hydraulic binders (eg calcium hydroxide) than black slag and is therefore more suitable for sinter bonding.

It is possible that the inorganic binder contains slag in combination with cement.

The use of slag, white and/or black, which can be classified as an alkaline binder, improves the efficiency of sinter bonding, making the compacted products more dense, which improves the efficiency of further use in an electric arc furnace. There is also an economic benefit, since the slag can be obtained cheaply as waste.

Perhaps a solution in which the cement, if present, is contained in an amount of 6 wt. % up to 14 wt. %, preferably from 8 wt. % up to 12 wt. % with respect to said at least one fraction M, M1, M2, M3 of the by-product.

Solutions are possible in which the cement is Portland cement, preferably type III.

In another solution, the slag is present in an amount of 2 wt. % up to 10 wt. %, preferably from 5 wt. % up to 9 wt. % with respect to at least one fraction M, M1, M2, M3 of the by-product.

White slag refers to slag obtained as waste from secondary metallurgy processes, such as steel refining processes, which are usually carried out in a ladle.

Black slag is the slag obtained as waste from the melting processes in the electric arc furnace.

The addition of slag in the production of a solid sintered product has the advantage of improving the mechanical properties of the agglomerate itself due to the formation of acicular calcium hydrosilicate and increasing the hygroscopicity of the agglomerate itself to hold the water needed to hydrate the cement, if present.

In addition, the addition of slag makes it possible to reduce the required amount of cement or similar binder compared to the prior art and makes it possible to control the alkalinity of the slag in the furnace, possibly reducing the addition of slag forming agents.

Solutions are possible in which the agglomerated product contains at least one additive selected from the following group: calcium oxide (CaO), also called quicklime, and calcium carbonate (CaCO ₃ ).

A solution is possible in which the proposed solid agglomerated product does not contain bentonite and/or organic binders, such as, for example, molasse, as the main binders.

The fact is that these substances impart inadequate mechanical properties to the agglomerated product if it is subjected to temperatures above 400°C. The aim of the invention may also be to obtain an agglomerated product that retains its mechanical resistance characteristics at temperatures above 400°C, preferably above 600°C. This makes it possible, for example, to add these aggregated products to preheated direct reduced iron at temperatures around 600°C.

The solid agglomerated product may be compressed, possibly by extrusion, into a product having a cross section that is circular, rectangular, polygonal, or also triangular, and the like. shape.

In particular, the solid agglomerated product may be an extruded product.

In some embodiments, the solid agglomerated product may be prepared in the form of P granules. Each P granule may advantageously be 8 mm to 25 mm in size and 4 g to 25 g in weight. for use in electric arc furnaces. With such a mass and dimensions greater than in the known solutions, the production of granules is facilitated and simplified, which, being loaded into the furnace, easily reach the metal pool, and do not remain on the surface, for example, on top of the slag.

If pellets P are produced, then the production process, the flowchart of which is shown in FIG. 1 provides for the use of a single by-product fraction M with particle sizes less than 100 µm.

A single fraction M of the by-product may come from a single area of the steel line where this fraction originated, or it may be taken from different parts of the steel line.

In addition, a single by-product fraction M may be the result of an earlier crushing and mixing process of several by-product fractions having a much larger particle size than those used for the P pellet process.

A preferred solution is when at least 50% of the by-product fraction M has particle sizes less than 25 µm.

In one embodiment, it is provided that at least 80% of the fraction M of the by-product has a particle size of less than 45 microns.

This solution provides that if at least part of the fraction of the by-product has a particle size of more than 100 μm, then in order to obtain the desired particle size, this part, or the entire fraction, is subjected to crushing.

The proposed method then involves determining, for example, by laboratory tests, the mass amount of iron Fe ²⁺ _tot contained in the first part containing iron (II) oxide (FeO), and the mass amount of iron Fe ³⁺ _tot contained in the second part containing iron oxide (III) Fe ₂ O ₃ ).

By way of example only, it may be possible to determine the mass amounts of iron Fe ²⁺ _tot and iron Fe ³⁺ _tot according to the following formulae:

Fe ²⁺ _tot \u003d% Fe ²⁺ _ _M * M

Fe ³⁺ _tot \u003d% Fe ³⁺ _ _M * M

where M is the mass of the by-product fraction, %Fe ²⁺ _ _M and % Fe ³⁺ _ _M are, respectively, the percentage of iron Fe ^{2+ and} iron Fe ³⁺ present in the by-product fraction.

In some embodiments, %Fe ²⁺ _ _M and %Fe ³⁺ _ _M can be measured by experiment and/or using measurement methods.

A solution is possible, providing that the by-product fraction M has a degree of metallization, that is, a metallic iron content relative to the total iron content, from 15% to 40%.

A solution is possible, in which the predisposition of at least the solid fuel fraction CR and the binder is provided. The amount of solid fuel fraction CR is determined by the formulas given above.

A solution is possible in which the binders, or part of them, and the solid fuel fraction CR, or part thereof, are subjected to crushing in order to reduce the particle size, for example, to less than 100 μm.

Then the by-product fraction, binders and solid fuel fraction CR are mixed with the addition of water to obtain a mixture of ZP.

In one embodiment, dosing of the inorganic binder, solid fuel fraction CR and fraction M of the by-product is performed prior to mixing.

The process for preparing granules P then involves agglomerating or cold granulating the mixture ZP to obtain agglomerate particles SP.

Cold agglomeration can be carried out with a rotary disc granulator. Due to the rotation of the disk and the cohesion and plasticity of the by-product fraction, and the addition of the proper amount of water, spherical nuclei are formed, which increase in size during the rotation of the disk, and then are discharged as an SP agglomerate with particles of essentially spherical shape.

The method further includes a sorting operation in which the SP agglomerate is screened leaving only particles of a certain size.

Agglomerate SP with particle sizes less than required is sent for recycling, for example, loaded into a mixing plant in the mixing stage, or into a granulator.

After sorting, curing is provided. At this stage, the particles of the agglomerate SP acquire the desired mechanical properties of the granules P, also due to hydration reactions occurring between binders, for example between cement and slag.

In one embodiment, the solid agglomerated product may be produced in the form of briquettes B. The size of the briquette B may be from 20 mm to 60 mm and its weight from 15 g to 300 g.

In the case of the preparation of briquettes B, the production method, the block diagram of which is presented in figure 2, provides for the presence of at least two, in this case three, fractions M1, M2 and M3 of the by-product, while at least the first fraction has a particle size of less than 100 µm, and in the second fraction, and in this case in the second fraction M2 and the third fraction M3 of the by-product, particles with sizes from 100 µm to 8 mm, preferably from 100 µm to 4 mm, constitute at least 80% of the by-product itself.

Preferably, the solution is when at least 50% of the first fraction M1 of the by-product has a particle size of less than 25 microns.

A solution is possible in which the degree of metallization of the first fraction M1 of the by-product, that is, the degree of reduction of iron oxides (FeO and/or Fe ₂ O ₃ ) to metallic iron in it, is from 15% to 40%.

In yet another embodiment, the degree of metallization of the second fraction M2 of the by-product, that is, the degree of reduction of iron oxides (FeO and/or Fe ₂ O ₃ ) to metallic iron, is below 6%.

In yet another embodiment, the degree of metallization of the third fraction of the MOH by-product, that is, the degree of reduction of iron oxides (FeO and/or Fe ₂ O ₃ ) to metallic iron in it, is from 70% to 100%.

During the implementation of the proposed method, the step of determining for all fractions M1, M2 and M3 of the by-product, for example, by laboratory tests, the mass amount of iron Fe ²⁺ _tot contained in the first part containing iron oxide (II) (FeO), and the mass the amount of iron Fe ³⁺ _tot contained in the second part containing iron oxide (III) (Fe ₂ O ₃ ).

This determination can be made for each fraction M1, M2 or M3 of the by-product separately.

By way of example only, in an illustrative variant with three by-product fractions, it is possible to determine, for example, by laboratory tests, the corresponding value of the percentage of iron Fe ²⁺ , Fe ³⁺ in each by-product fraction, that is, to determine %Fe ²⁺ _ _M1 , % Fe ³⁺ _ _M1 , % Fe ²⁺ _ _M2 , % Fe ³⁺ _ _M2 , % Fe ²⁺ _ _M3 , % Fe ³⁺ _ _M3 .

As a function of the values of the percentage of iron Fe ²⁺ , Fe ³⁺ , you can determine the mass amounts of Fe ²⁺ _tot and Fe ³⁺ _tot using the following formulas:

Fe ²⁺ _tot \u003d% Fe ²⁺ _ _M1 * M1 +% Fe ²⁺ _ _M2 * M2 +% Fe ²⁺ _ _M3 * M3

Fe ³⁺ _tot \u003d% Fe ³⁺ _ _M1 * M1 +% Fe ³⁺ _ _M2 * M2 +% Fe ³⁺ _ _M3 * M3.

These mass amounts are then used to determine the mass of solid fuel fraction CR to be added to produce briquettes B.

It is envisaged to introduce an inorganic binder capable of binding together the fractions M1, M2, M3 and the solid fuel fraction CR.

With regard to the method for the production of granules, it is also provided that the binders or a part of them and the solid fuel fraction CR or a part thereof can be crushed in order to reduce the particle size, for example, to a value of less than 100 μm.

The by-product fractions M1, M2 and M3, the binders and the solid fuel fraction CR are then mixed with the addition of water to obtain a mixture ZB.

In one embodiment, dosing is performed prior to mixing the inorganic binder, the CR solid fuel fraction, and the by-product fractions M1, M2, and M3.

The preparation of briquettes B then involves cold agglomeration or briquetting of the mixture ZB in order to obtain agglomerate SB.

Cold agglomeration can be carried out by pressing, for example, in a mechanical compaction cycle at high pressures.

By way of example only, the ZB mixture can be passed between two counter-rotating rollers. Molds are made on the surface of these rolls. As the ZB mix passes between the rollers, the material is compacted and briquettes of the desired shape and size are formed.

The method further provides for sorting, during which the briquettes obtained by cold agglomeration are screened, leaving only briquettes of a certain size.

Briquettes with sizes less than required are sent for recycling, for example, they are loaded into a mixing plant at the mixing stage, or into a briquette press.

After sorting, curing is provided. At this stage, the briquettes B acquire the desired mechanical properties due to hydration reactions taking place between binders, for example between cement and slag.

The table below provides compositional data for two examples of a solid agglomerated product in dry matter, i.e. excluding water.

Another aspect of the invention provides that, after curing, the granules P have a compressive strength (that is, the ability to withstand the weight placed on the granule before breaking) of more than 300 N per granule.

In addition, the pellets P obtained as described above can be subjected to a drop resistance test, i.e. the ability to withstand repeated falls from a certain height, the number of which should be more than 20.

Another aspect of the present invention provides that, after curing, the briquettes B have a compressive strength (ie the ability to withstand the weight placed on the briquette before breaking) of more than 1200 N per briquette.

It should be understood that modifications and/or additions are possible within the scope of the invention with respect to the solid agglomerated product described above.

It will also be understood that although the invention has been described in terms of specific examples, the skilled artisan will be able to create many other equivalent solid agglomerated products that have the features set forth in the appended claims and therefore fall within the scope of protection provided therein.

Claims (24)

1. Solid agglomerated product suitable for use as a charge material for an electric arc furnace, containing - at least one fraction (M, M1, M2, M3) of a by-product of the steelmaking process, having a first part containing iron (II) oxide (FeO) and a second part containing iron (III) oxide (Fe ₂ O ₃ ) , - solid fuel fraction (CR) containing carbon (C_fix), - at least one inorganic binder for agglomerating said at least one fraction (M, M1, M2, M3) of the by-product and the solid fuel fraction (CR) with each other and imparting to the agglomerated product mechanical characteristics that ensure storage and transportation, characterized in that said solid fuel fraction (CR) is contained in a mass amount determined by the formula CR=K⋅CS/C_fix, where K is a constant number from 1.2 to 2.5, CS is the mass amount of stoichiometric carbon, determined by the formula CS=0.11⋅(Fe ²⁺ _tot) + 0.16⋅(Fe ³⁺ _tot), where Fe ²⁺ _tot is the mass amount of iron contained in the mentioned first part, Fe ³⁺ _tot - mass amount of iron contained in said second part, while the inorganic binder at least partially contains slag, while said slag is white slag and/or black slag, moreover, white slag is a waste from secondary metallurgy processes, and black slag is a waste from the smelting process in the electric arc furnace. 2. Product according to claim 1, characterized in that said at least one binder contains slag in combination with cement. 3. The product according to p. 2, characterized in that the cement content is from 6 to 14 wt. %, preferably from 8 to 12 wt. % relative to said at least one fraction (M, M1, M2, M3) of the by-product. 4. The product according to p. 2, characterized in that the slag content is from 2 to 10 wt. %, preferably from 5 to 9 wt. % with respect to said at least one fraction (M, M1, M2, M3) of the by-product. 5. The product according to any one of paragraphs. 1-4, characterized in that it contains at least one additive selected from the following group: calcium oxide (CaO), calcium carbonate (CaCO ₃ ). 6. The product according to any one of paragraphs. 1-5, characterized in that it is obtained in the form of granules (P). 7. The product according to any one of paragraphs. 1-5, characterized in that it is obtained in the form of briquettes (B). 8. The product according to any one of paragraphs. 1-5, characterized in that it is obtained by extrusion. 9. A method for the production of a solid agglomerated product, comprising the following steps: - ensure the presence of at least one fraction (M, M1, M2, M3) of a by-product having a first part containing iron (II) oxide (FeO) and a second part containing iron (III) oxide (Fe ₂ O ₃ ) , - ensure the presence of a solid fuel fraction (CR) containing carbon (C_fix), mixing said at least one fraction (M, M1, M2, M3) of the by-product with said solid fuel fraction (CR) and at least one inorganic binder and agglomerating or cold granulating, sorting and curing the resulting agglomerate particles to obtain said solid agglomerated product, characterized in that before mixing, the mass amount of the solid fuel fraction (CR) is determined by the formula CR=K⋅CS/C_fix, where K is a constant number from 1.2 to 2.5, CS is the mass amount of stoichiometric carbon, determined by the formula CS=0.11⋅(Fe ²⁺ _tot) + 0.16⋅(Fe ³⁺ _tot), where Fe ²⁺ _tot is the mass amount of iron contained in the first part, Fe ³⁺ _tot - mass amount of iron contained in the second part, while said inorganic binder at least partially contains slag, while said slag is white slag and/or black slag, and white slag is a waste from secondary metallurgy processes, and black slag is a waste product of the electric arc furnace smelting process. 10. The method according to claim 9, characterized in that said at least one binder contains slag in combination with cement. 11. Method according to claim 9 or 10, characterized in that at least one additive from the following group is added at said mixing step: calcium oxide (CaO), calcium carbonate (CaCO ₃ ). 12. The method according to any one of paragraphs. 9-11, characterized in that it contains the stage of preparation of granules (P), while before mixing, a single fraction (M) of a by-product with a particle size of less than 100 microns is provided. 13. The method according to any one of paragraphs. 9-11, characterized in that it contains the step of preparing briquettes (B), while providing the first fraction (M1) of the by-product with particle sizes less than 100 μm and at least the second fraction (M2, M3) of the by-product with particle sizes from 100 µm to 8 mm.

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