KR20240018206A - Facility for manufacturing molten iron and method for manufacturing molten iron - Google Patents

Abstract

The present invention relates to a molten iron production facility and a molten iron production method, and more specifically, to a molten iron production facility and a molten iron production method for producing reduced iron and dissolving the produced reduced iron to produce molten iron.
A molten iron manufacturing facility according to an embodiment of the present invention includes a reduction unit capable of producing reduced iron; A dissolving portion capable of dissolving reduced iron; and a processing unit capable of receiving reduced iron from the reduction unit, installed to receive exhaust gas discharged from the dissolution unit, and reacting the supplied reduced iron with the exhaust gas to supply the reacted reduced iron to the dissolution unit. .

Description

Molten iron manufacturing equipment and molten iron manufacturing method {FACILITY FOR MANUFACTURING MOLTEN IRON AND METHOD FOR MANUFACTURING MOLTEN IRON}

The present invention relates to a molten iron production facility and a molten iron production method, and more specifically, to a molten iron production facility and a molten iron production method for producing reduced iron and dissolving the produced reduced iron to produce molten iron.

Generally, molten iron, or molten iron, is manufactured through a blast furnace process. The blast furnace process is carried out by processing iron ore and coal into a form suitable for use, placing them in a blast furnace, and blowing hot air into them. Here, hot air burns coal, and the carbon monoxide gas generated at this time causes a reduction reaction that removes oxygen from iron ore. Additionally, heat over 1,500°C generated inside the blast furnace causes a melting reaction that melts iron ore or iron reduced by carbon monoxide gas, producing molten iron. In this blast furnace process, reduction reaction and melting reaction are carried out simultaneously within the blast furnace by coal and carbon monoxide gas generated therefrom. However, such a blast furnace process has the problem of generating a large amount of carbon dioxide, which causes environmental problems such as global warming, due to a reduction reaction between carbon monoxide gas and iron ore.

To solve this problem, hydrogen reduction steelmaking process technology, which produces molten iron using hydrogen gas instead of fossil fuels such as coal, is being researched and developed. Fossil fuels such as coal generate carbon dioxide when they react with iron ore, but since hydrogen gas reacts with iron ore to generate water or water vapor, the hydrogen reduction steelmaking process can innovatively reduce carbon emissions in manufacturing molten iron. .

In this hydrogen reduction steelmaking process, reduced iron is produced by reducing iron ore, and molten iron is produced by dissolving the produced reduced iron. However, reduced iron produced by the reaction between hydrogen gas and iron ore has a very high melting point, so there is a problem that a lot of energy is required to dissolve it. In addition, in the process of dissolving reduced iron, a large amount of exhaust gas is generated, and it is necessary to prepare a method to recycle the large amount of exhaust gas generated in this way.

KR 10-1699236 B1

The present invention provides a molten iron manufacturing facility and a molten iron manufacturing method that can minimize the amount of energy required for melting.

A molten iron manufacturing facility according to an embodiment of the present invention includes a reduction unit capable of producing reduced iron; A dissolving portion capable of dissolving reduced iron; and a processing unit capable of receiving reduced iron from the reduction unit, installed to receive exhaust gas discharged from the dissolution unit, and reacting the supplied reduced iron with the exhaust gas to supply the reacted reduced iron to the dissolution unit. .

It further includes; an exhaust gas supply line installed to connect the dissolving unit and the processing unit; wherein the reducing unit includes a reduction furnace having a reduction space capable of producing reduced iron by receiving a reducing gas; wherein the dissolving unit includes the It may include an electric furnace connected to an exhaust gas supply line and having a dissolution space capable of dissolving reduced iron supplied from the treatment unit using electric heat.

The processing unit includes a main body having a processing space; a reduced iron inlet provided in the main body to allow reduced iron to flow into the processing space; and an exhaust gas inlet provided in the main body and connected to the exhaust gas supply line to allow exhaust gas to flow into the processing space, wherein the exhaust gas inlet may be provided at a lower position than the reduced iron inlet.

The processing unit may further include a heater installed in the main body to heat the processing space.

The processing unit includes a collector connected to the main body to collect reduced iron flowing out from the main body; and a circulation line connecting the collector and the main body so that the reduced iron collected from the collector can be supplied to the main body.

The processing unit may further include a supplementary gas supply unit connected to the main body to supply supplemental gas having at least some of the same components as the exhaust gas to the processing space.

A raw material supply unit having a storage space for storing raw materials and installed to supply the raw materials stored in the storage space to the reduction space; and an exhaust gas branch line branched from the exhaust gas supply line and capable of supplying a portion of the exhaust gas discharged from the electric furnace to the raw material supply unit.

The exhaust gas branch line may be connected to the raw material supply unit to directly supply exhaust gas to the storage space or to transfer heat of the exhaust gas to air supplied to the storage space.

a purge gas supply line connected to the reduction furnace to supply purge gas to the reduction space; and a purge gas branch line branched from the purge gas supply line and capable of supplying a portion of the purge gas supplied to the reduction space to the processing space.

Meanwhile, a method for producing molten iron according to an embodiment of the present invention includes a process of producing reduced iron; A process of reacting the produced reduced iron with a processing gas; A process of dissolving the reacted reduced iron to produce a molten product; and using at least a portion of the exhaust gas generated in the process of producing the melt as a processing gas to react with reduced iron.

The process of manufacturing the reduced iron includes preheating the raw material using the exhaust gas; and a process of reducing the preheated raw material by reacting it with a reducing gas.

The process of preheating the raw material may include spraying the exhaust gas onto the raw material, or spraying air heated by receiving heat from the exhaust gas onto the raw material.

The raw material may include powdered iron ore having a particle size greater than 0 mm and less than or equal to 8 mm.

The processing gas may include a gas containing a carbon component, and the process of reacting with the processing gas may include carbonizing at least a portion of the reduced iron.

In the process of reacting the reduced iron with the processing gas, the produced reduced iron can be reacted with the processing gas without separate heat treatment.

The process of reacting the reduced iron with the processing gas may include reacting the produced reduced iron with the processing gas at a temperature of 600 to 800°C.

A process of collecting reduced iron flowing out from a processing space where the reduced iron reacts with a processing gas; and a process of supplying the collected reduced iron to the treatment space.

The process of producing the reduced iron includes supplying a purge gas to a reduction space for producing the reduced iron, and the process of reacting the reduced iron with the processing gas includes a portion of the purge gas supplied to the reduction space. It may include a process of supplying to the processing space.

In the process of using the processing gas, the exhaust gas and a supplementary gas having at least some of the same components as the exhaust gas may be used as the processing gas.

The exhaust gas may include carbon monoxide gas, and the supplemental gas may include at least one of natural gas and biomass gas.

According to an embodiment of the present invention, the melting point of the reduced iron can be lowered by reacting the exhaust gas generated during the process with the reduced iron, thereby minimizing the amount of energy used to dissolve the reduced iron.

In addition, by reacting reduced iron produced at high temperature directly with high temperature exhaust gas, equipment and resources required for the reaction can be minimized.

In addition, energy can be efficiently recovered by using the sensible heat of the high-temperature exhaust gas for preheating raw materials and producing hydrogen gas.

1 is a diagram schematically showing a molten iron manufacturing facility according to an embodiment of the present invention.
Figure 2 is a diagram illustrating a reduction furnace for producing reduced iron and an electric furnace for dissolving reduced iron.
Figure 3 is a diagram illustrating the structure of a processing unit according to an embodiment of the present invention.
Figure 4 is a diagram showing conditions under which reduced iron reacts with exhaust gas.
Figure 5 is a diagram showing preheating of raw materials using exhaust gas in the raw material supply unit.
Figure 6 is a diagram schematically showing a method for manufacturing molten iron according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. However, the present invention is not limited to the embodiments disclosed below and will be implemented in various different forms. The embodiments of the present invention only serve to ensure that the disclosure of the present invention is complete and to those of ordinary skill in the art. It is provided to provide complete information. In order to explain the invention in detail, the drawings may be exaggerated, and like symbols in the drawings refer to like elements.

Figure 1 is a diagram schematically showing a molten iron manufacturing facility according to an embodiment of the present invention, Figure 2 is a diagram illustrating a reduction furnace for producing reduced iron and an electric furnace for dissolving reduced iron, and Figure 3 is a diagram showing the present invention. This is a diagram illustrating the structure of a processing unit according to an embodiment. In addition, Figure 4 is a diagram showing conditions under which reduced iron reacts with exhaust gas, and Figure 5 is a diagram showing preheating of raw materials using exhaust gas in the raw material supply unit. In the drawing, arrows indicated by dotted lines indicate the flow of raw materials and reduced iron, and arrows indicated by solid lines indicate the flows of by-products and gases.

1 to 5, the molten iron manufacturing facility according to an embodiment of the present invention includes a reduction unit 500 capable of producing reduced iron, a dissolution unit 700 capable of dissolving reduced iron, and the reduction unit 500. ), and is installed to receive reduced iron from the dissolving unit 700, and reacts the supplied reduced iron with the exhaust gas to supply the reacted reduced iron to the dissolving unit 700. Includes (600). In addition, the molten iron manufacturing facility according to an embodiment of the present invention includes a raw material supply unit 100 installed to supply raw materials to the reduction unit 500 and a reduction gas supply unit installed to supply reducing gas to the reduction unit 500. (200) may be further included.

The raw material supply unit 100 is installed to supply raw materials to the reduction unit 500. Here, the raw material may include iron ore, and the iron ore may include finely divided iron ore, that is, powdered iron ore, having a particle size greater than 0 mm and less than or equal to 8 mm. The raw material supply unit 100 may include a storage device 110 having a storage space for storing raw materials. Raw materials may be stored in the storage space of the storage unit 110 for a long time, or may be temporarily stored before supplying the raw materials to the reduction unit 500. Such a reservoir 110 may include, for example, a hopper.

Raw materials may be preheated in the storage space of the reservoir 110, and the raw materials preheated in the storage space may be supplied to the reduction unit 500. At this time, the reservoir 110 can preheat the raw material by receiving a portion of the exhaust gas discharged from the melting unit 700, and for this purpose, the molten iron manufacturing facility according to an embodiment of the present invention branches off from the exhaust gas supply line (EL). It may further include an exhaust gas branch line (EDL) capable of supplying a portion of the exhaust gas discharged from the dissolving unit 700 to the reservoir 110. Preheating of raw materials using exhaust gas supplied through an exhaust gas branch line (EDL) will be described later with reference to FIG. 5.

The reducing gas supply unit 200 is installed to store the reducing gas and supply the reducing gas to the reducing unit 500. Here, the reducing gas may include hydrogen gas, and hydrogen gas may be included in a ratio of 80 to 100% of the total reducing gas. Hydrogen gas stored in the reducing gas supply unit 200 may be produced by electrolyzing water, but is not limited thereto and may be produced by various methods such as decomposing ammonia gas or producing hydrogen gas by chemically reacting natural gas. It can be. For example, ammonia gas can be decomposed into hydrogen gas and nitrogen gas at high temperature, the decomposed hydrogen gas can be used as a reducing gas, and the nitrogen gas can be used as a purge gas, which will be described later.

The reducing gas supply unit 200 may supply reducing gas to the reduction unit 500 through reduction gas supply lines RL1 and RL2 that connect the reduction gas supply unit 200 and the reduction unit 500 to each other. At this time, the amount of reducing gas supplied by the reducing gas supply unit 200 to the reducing unit 500 may be more than twice the amount required to reduce all the raw materials supplied to the reducing unit 500. In order to improve the reaction efficiency between raw materials and reducing gas, the amount of reducing gas can be controlled, for example, to a range of two to three times the amount required to reduce all of the raw materials supplied to the reduction unit 500. .

A heating unit 300 may be installed in the reducing gas supply lines RL1 and RL2 to heat the reducing gas supplied from the reducing gas supply unit 200 to the reducing unit 500 . In the reduction unit 500, a raw material containing iron ore and a reducing gas containing hydrogen gas react to reduce iron ore. Since this reaction between iron ore and hydrogen gas is a strong endothermic reaction, the reaction efficiency can be improved when the hydrogen gas supplied to the reduction unit 500 is heated and supplied to a temperature of 800 ℃ or higher, more preferably 850 ℃ or higher. . Accordingly, the heating unit 300 is connected to the reduction gas supply unit 200 and the first reduction gas supply line RL1, and is connected to the reduction unit 500 and the second reduction gas supply line RL2, thereby providing the first reduction gas supply line RL2. Low-temperature hydrogen gas supplied through the gas supply line RL1 may be heated to a temperature of 800 to 1200° C. and supplied to the reduction unit 500 through the second reduction gas supply line RL2. Since the heating unit 300 may have various structures for heating the reducing gas by direct or indirect heating, a detailed description thereof will be omitted.

The molten iron manufacturing facility according to an embodiment of the present invention may further include a purge gas supply unit 400 that is installed to store purge gas and supply the purge gas to the reduction unit 500. The reduction unit 500 has a reduction space capable of producing reduced iron, and the reduction space needs to be purged for maintenance between processes. Additionally, there are cases where purge gas needs to be supplied during the process. For example, when using powdered iron ore as a raw material, a purge gas may be supplied to increase the fluidity of the powdered iron ore to prevent it from sticking in the reduction space. Accordingly, the purge gas supply unit 400 may supply a purge gas to the reduction space through a purge gas supply line PL that connects the purge gas supply unit 400 and the reduction unit 500, and the purge gas may be nitrogen. An inert gas such as can be used.

The reduction unit 500 can produce reduced iron by reducing raw materials. That is, the reducing unit 500 can receive iron ore as a raw material from the raw material supply unit 100, receive a reducing gas from the reducing gas supply unit 200, and react the iron ore with the reducing gas to produce reduced iron. This reduction unit 500 may include a reduction furnace having a reduction space capable of producing reduced iron using a reducing gas. Such a reduction reactor may include a fluid reduction reactor (510, 520, 530, 540) that produces reduced iron while flowing raw materials, and the fluid reduction reactor (510, 520, 530, 540) may be provided as a single unit. In order to effectively reduce low-grade iron ore or powdered iron ore with a low iron content, as shown in FIG. 2, a plurality of fluidized reduction furnaces (510, 520, 530, and 540) are connected to sequentially move the raw materials to produce reduced iron. It may be possible. At this time, there is no limit to the number of fluid reduction furnaces 510, 520, 530, and 540, but in order to sufficiently reduce the raw materials, the reduction unit 500 includes a first fluid reduction furnace 510, as shown in FIG. 2, It may be composed of four reduction reactors including a second fluid reduction reactor 520, a third fluid reduction reactor 530, and a fourth fluid reduction reactor 540. At this time, the raw material supply unit 100 may supply raw materials to the first fluidized reduction reactor 510, and the reducing gas supply unit 200 may supply reducing gas to the fourth fluidized reduction reactor 540. The raw material supplied to the first fluid reduction furnace 510 is reduced by sequentially moving through the second fluid reduction furnace 520, the third fluid reduction furnace 530, and the fourth fluid reduction furnace 540 to be manufactured into reduced iron. You can.

The reduced iron produced in the reduction unit 500 is supplied to the processing unit 800, which will be described later. As shown in FIG. 2, the reduced iron produced through the first fluid reduction reactor 510, the second fluid reduction reactor 520, the third fluid reduction reactor 530, and the fourth fluid reduction reactor 540 is 4 is discharged from the fluidized reduction furnace 540 and supplied to the treatment unit 800. Here, as described above, preheated raw materials and a reducing gas of 800°C or higher are supplied to the reduction space to produce reduced iron. Accordingly, the reduced iron produced in the reduction unit 500 is discharged at a high temperature of, for example, 600 to 800°C, even taking heat loss into account. In this way, the reduced iron discharged at a high temperature can be directly supplied to the processing unit 800 without going through a separate heat treatment device. In the processing unit 800, the equipment and resources required for the reaction can be minimized by directly reacting the reduced iron produced at high temperature with the high-temperature exhaust gas, which will be described later in relation to the processing unit 800.

Meanwhile, in the reduction unit 500, a large amount of by-products are discharged in addition to reduced iron. By-products discharged from the reduction unit 500 may include steam. As described above, in the reduction unit 500, iron ore and hydrogen gas react to produce reduced iron. At this time, the oxygen component of the iron ore and the hydrogen component of the hydrogen gas react to generate a large amount of water vapor in the reduction space, and the generated water vapor is discharged from the reduction unit 500 as a by-product. Additionally, by-products discharged from the reduction unit 500 may include hydrogen gas and nitrogen gas. As described above, the reducing gas is supplied in a range of two to three times the amount required to reduce all the raw materials supplied to the reduction unit 500, so the remaining hydrogen gas that has not reacted with the raw materials is stored in the reduction unit (500). 500) are discharged as by-products. Additionally, as described above, a purge gas, for example, nitrogen gas, may be supplied to the reduction unit 500 for various reasons. In this way, the nitrogen gas supplied for purge is discharged from the reduction unit 500 as a by-product. The by-products move along the flow of reducing gas within the reduction unit 500 and are discharged from the first flow reduction furnace 510. The discharged by-products are discharged through the by-product supply line BL connected to the reduction unit 500. It can be supplied to the extraction unit 600 through.

That is, the molten iron manufacturing facility according to an embodiment of the present invention is installed to receive by-products discharged from the reduction unit 500, and further includes an extraction unit 600 capable of extracting hydrogen gas from the by-products. can do.

The extraction unit 600 extracts hydrogen gas from the by-products discharged from the reduction unit 500. As described above, by-products discharged from the reduction unit 500 include water vapor, hydrogen gas, and nitrogen gas. The extraction unit 600 is connected to the reduction unit 500 through the byproduct supply line BL, and can extract hydrogen gas from the byproduct supplied through the byproduct supply line BL. This extraction unit 600 can extract hydrogen gas from by-products using a pressure swing absorption (PSA) method. That is, the pressure swing adsorption method extracts gas using the adsorption selectivity of each component with respect to the adsorbent, and the extraction unit 600 extracts hydrogen gas from by-products containing various gases in addition to hydrogen gas. A carbon molecular sieve capable of adsorption can be used as an adsorbent. At this time, the hydrogen component adsorbed on the adsorbent can be desorbed and extracted as hydrogen gas, and the extraction unit 600 can extract hydrogen gas from the by-product by repeatedly performing adsorption and desorption of the hydrogen component.

Residue discharged from the extraction unit 600 without being adsorbed may include water vapor and nitrogen gas. Here, the residue containing water vapor and nitrogen gas may be supplied to the reduction unit 500 as a purge gas. Water vapor is a reaction product generated by the reaction between iron ore, which is a raw material, and hydrogen gas in the reducing gas, and has low reactivity with the iron ore and the reducing gas, so it can be supplied to the reduction unit 500 as a purge gas. Additionally, when water vapor is supplied to the reduction unit 500 as a purge gas, the heat of the water vapor can be utilized for the reduction reaction, thereby saving the energy required for the reduction reaction. In order to supply the residue to the reduction unit 500 as a purge gas, a residue discharge line (not shown) may be connected to the extraction unit 600, and the residue discharge line may be connected to the purge gas supply line (PL), or Of course, it can be directly connected to the reduction unit 500 and supply the residue to the reduction unit 500 through a path different from the purge gas.

Hydrogen gas extracted from the extraction unit 600 can be used for various purposes. For example, the reduction unit 500 can reduce the raw material, that is, iron ore, using extracted hydrogen gas. Hydrogen gas is used in a large amount, more than twice the amount required to reduce all the raw materials supplied to the reduction unit 500, but is a very expensive gas, so it is extracted from the extraction unit 600 to reduce costs through resource recycling. The hydrogen gas can be reused as a reducing gas to reduce iron ore. For this purpose, a hydrogen gas supply line (HL) is connected to the extraction unit 600, and the hydrogen gas supply line (HL) is connected to the first reducing gas supply line (RL1), so that the extraction unit 600 supplies the first reducing gas. Hydrogen gas can be supplied to the supply line (RL1), and the extracted hydrogen gas is supplied to the reduction unit ( 500) and can be used for reduction of iron ore.

The dissolving unit 700 can receive reduced iron reacted from the processing unit 800, which will be described later, and dissolve it in various ways. For example, the dissolving unit 700 may receive reacted reduced iron in a fine or compacted state from the processing unit 800 and heat it to dissolve it. In addition, the melting unit 700 may receive additional iron scrap in addition to the reacted reduced iron and melt the reacted reduced iron and iron scrap together. This dissolution unit 700 may include electric furnaces 710 and 720 having a dissolution space capable of dissolving the reacted reduced iron using electric heat. Such electric furnaces 710 and 720 may include an electric furnace body 710 having a dissolution space and an electrode 720 at least partially disposed in the dissolution space to generate electric heat. When the reacted reduced iron is charged into the melting space, the electric furnaces 710 and 720 apply power to the electrode 720 to dissolve the reacted reduced iron.

In the dissolution unit 700, a recarburizing agent containing a carbon component is introduced to adjust the carbon content of the melt produced by dissolving the reacted reduced iron. Additionally, a recarburizing agent may be added to generate a large amount of slag when dissolving the melt. In this case, the electrode 720 can generate resistance heat by receiving power while immersed in the slag, and the reduced iron can be more easily dissolved by the generated resistance heat. Meanwhile, at least partially unreduced raw materials, that is, partially reduced reduced iron or iron ore, may be supplied to the dissolution unit 700. In this way, at least a part of the unreduced raw material has an oxygen component, and within the dissolution space, the oxygen component reacts with the carbon component of the recarburizer or the carbon component of the reacted reduced iron, which will be described later. Accordingly, the dissolving unit 700 receives the reacted reduced iron from the processing unit 800 and while dissolving it, exhaust gas containing carbon monoxide gas, that is, exhaust gas having a high carbon monoxide concentration (CO-rich), is discharged. In this way, the exhaust gas discharged from the dissolution unit 700 is discharged at a high temperature of about 1,200° C. or higher.

When the reduced iron produced in the reduction unit 500 is charged to the dissolution unit 700 without any additional treatment, a lot of energy is required to dissolve the reduced iron in the dissolution unit 700. That is, the reduced iron produced in the reduction unit 500 without any additional treatment has a component of metallic iron (Fe), that is, pure iron, and such pure iron has a melting point of about 1,538°C. In addition, reduced iron contains a large amount of gangue in addition to these pure iron components, and reduced iron can only be dissolved by heating to a temperature above the melting point of pure iron. In addition, when the reduced iron produced in the reduction unit 500 is charged to the melting unit 700 without separate treatment, the use of a large amount of recarburizing agent is required to control the carbon content of the melt.

On the other hand, when reduced iron is carbonized, the pure iron component changes into a cementite (Fe ₃ C) phase, which has a melting point of about 1,200°C or less. In this way, when at least some of the components dissolve reduced iron that has changed to the cementite (Fe ₃ C) phase, the amount of energy required to dissolve the reduced iron can be minimized. Additionally, when melting reduced iron carbide, that is, iron carbide, the melt has some carbon content. Accordingly, when dissolving iron carbide, the amount of recarburizing agent used to control the carbon content of the melt can be minimized.

Therefore, in an embodiment of the present invention, the reduced iron supplied from the reduction unit 500 is reacted with the exhaust gas having a high carbon monoxide concentration (CO-rich) discharged from the dissolution unit 700, and the reacted iron carbide is transferred to the dissolution unit 700. A processing unit 800 that can supply is installed. To this end, the molten iron manufacturing facility according to an embodiment of the present invention may further include an exhaust gas supply line (EL) installed to connect the melting unit 700 and the processing unit 800.

At this time, the processing unit 800 includes a main body 810 having a processing space as shown in FIG. 3, a reduced iron inlet 812 provided in the main body 810 to allow reduced iron to flow into the processing space, and the main body ( 810) and includes an exhaust gas inlet 816 connected to the exhaust gas supply line (EL) to allow exhaust gas to flow into the treatment space.

The main body 810 has a processing space in which reduced iron supplied from the reduction unit 500 can be accommodated. In order to introduce reduced iron into the processing space, a reduced iron inlet 812 is provided in the main body 810, and a reduced iron supply pipe (FL) is connected to the reduced iron inlet 812, so that the reduced iron manufactured and transferred from the reduction unit 500 This reduced iron can flow into the treatment space through the supply pipe (FL). Additionally, exhaust gas discharged from the dissolving unit 700 may flow into the processing space of the main body 810. To this end, an exhaust gas inlet 816 may be formed in the main body 810, and the exhaust gas inlet 816 may be connected to the exhaust gas supply line EL. In Figure 3, the processing unit 800 is shown as consisting of a single body 810, but the processing unit 800 can carbonize the reduced iron by sequentially moving the reduced iron by connecting a plurality of bodies 810 to each other. am.

Here, the exhaust gas inlet 816 may be provided at a lower position than the reduced iron inlet 812. For example, as shown in FIG. 3, the exhaust gas inlet 816 may be provided on the lower surface of the main body 810, and the reduced iron inlet 812 may be provided on the side of the main body 810. In this way, by providing the exhaust gas inlet 816 at a lower position than the reduced iron inlet 812, the reduced iron supplied from the reduced iron inlet 812 can flow within the main body 810 and react with the exhaust gas. Meanwhile, the processing unit 800 may further include a dispersion plate 817 installed in the main body 810 and formed with a plurality of nozzles (not shown) to uniformly distribute the exhaust gas supplied from the exhaust gas inlet 816 into the processing space. You can.

At this time, the reduced iron produced in the reduction unit 500 is discharged at a high temperature of, for example, 600 to 800° C., and the discharged reduced iron is directly supplied to the treatment unit 800 without going through a separate heat treatment device. In addition, since high temperature exhaust gas of approximately 1,200°C or higher is supplied to the processing space, the processing space can maintain a temperature of 600 to 800°C even taking into account the heat loss of reduced iron during the transfer process. Accordingly, the processing unit 800 may not be installed with a separate heating means for heating the processing space. However, since it may be necessary to increase the temperature of the processing space during initial operation of the equipment, the processing unit 800 may further include a heater 820 installed in the main body 810 to heat the processing space. At this time, the heater 820 can be selectively operated to heat the processing space when it is necessary to heat the processing space. For example, the heater 820 may be installed on the side of the main body 810 to supply oxygen gas, and the supplied oxygen gas may react with the exhaust gas in the processing space to increase the temperature of the processing space. At this time, the amount of oxygen gas supplied from the heater 820 may be controlled to maintain the processing space within a temperature range of 600 to 800°C.

The treatment unit 800 carbonizes the reduced iron supplied from the reduction unit 500 by reacting it with the exhaust gas. As shown in the Bauer-Glaessner diagram showing the conditions under which reduced iron reacts with exhaust gas shown in FIG. 4, when the treatment space is maintained at a temperature of 600 to 800°C, the partial pressure of carbon monoxide and carbon dioxide in the treatment space are specified. If the conditions are met, it can be carbonized by reacting according to the reaction formula below.

[Reaction formula]

In other words, when reduced iron and exhaust gas at high temperature are supplied to the treatment space and the treatment space maintains a temperature of 600 to 800°C, the partial pressure of carbon monoxide (Pco) is equal to the partial pressure of carbon monoxide (Pco) and the partial pressure of carbon dioxide (Pco ₂₎ . ), if it has a value of about 90% or more of the combined value (Pco + Pco ₂ ), it reacts and is carbonized according to the above reaction formula. Here, as described above, the melting portion 700 is an electric furnace (710, 720) capable of dissolving reduced iron, that is, an ESF that is immersed in slag formed in the electric furnace main body 710 and can dissolve reduced iron with slag resistance heat. (Electric Smelting Furnace) or SAF (Submerged Arc Furnace). Such electric furnaces (710, 720) have a closed structure, so there is almost no inflow of oxygen or atmosphere, so the carbon dioxide content in the exhaust gas is very low, and the oxygen component of the unreduced raw material and the carbon component of the recarburizer react to produce a high carbon monoxide concentration. have That is, the partial pressure of carbon monoxide (Pco) of the exhaust gas discharged from such electric furnaces (710, 720) is about 90% of the sum of the partial pressure of carbon monoxide (Pco) and the partial pressure of carbon dioxide (Pco ₂ ) (Pco + Pco ₂ ). % or more, it is possible to effectively carbonize reduced iron under temperature conditions of 600 to 800°C.

Meanwhile, the molten iron manufacturing facility according to an embodiment of the present invention may further include a supplementary gas supply unit 900 installed to supply supplemental gas having at least some of the same components as exhaust gas to the processing space of the processing unit 800. The supplemental gas supply unit 900 may supply supplementary gas, that is, a carbon-containing gas having at least some of the same components as the exhaust gas, to the processing unit 800, and the supplemental gas supply unit 900 may supply carbon-containing gas through the supplemental gas supply line (SL). Gas may be supplied to the processing unit 800. Here, the supplementary gas supply line (SL) may be connected to the exhaust gas supply line (EL) to supply supplemental gas together with the exhaust gas, or may supply supplemental gas to the processing unit 800 through a path different from the exhaust gas supply line (EL), The supplementary gas may include at least one of natural gas containing carbon and biomass gas obtained by gasifying biomass.

In addition, the molten iron manufacturing facility according to an embodiment of the present invention is branched from the purge gas supply line (PL) and includes a purge gas branch line (PDL) that can supply a portion of the purge gas supplied to the reduction space to the processing space. More may be included. The processing space needs to be purged for maintenance, and purge gas can be supplied to prevent fine reduced iron from sticking to the processing space during the process. Accordingly, the purge gas branch line (PDL) may branch from the purge gas supply line (PL) to supply purge gas to the processing space.

In this way, the reduced iron, that is, iron carbide, reacted in the processing unit 800 is supplied to the dissolving unit 700. Here, the reaction between reduced iron and exhaust gas according to the above-mentioned reaction equation corresponds to an exothermic reaction. Accordingly, iron carbide supplied from the processing unit 800 to the dissolving unit 700 is discharged at a high temperature in a range similar to the temperature of the processing space, for example, 600 to 800° C., even considering heat loss. In this way, the iron carbide discharged in a high temperature state is directly supplied to the melting unit 700 in a high temperature state without going through a separate cooling device, thereby minimizing the amount of energy used for dissolving the reduced iron.

On the other hand, most of the reduced iron supplied to the treatment space reacts in the treatment space and then is supplied to the dissolution unit 700, but the reduced iron in fine powder does not react sufficiently with the exhaust gas, flows by the exhaust gas, and flows out from the treatment space together with the exhaust gas to the outside. It can be. Accordingly, the processing unit 800 may supply a collector 840 connected to the main body 810 to collect the reduced iron flowing out from the main body 810, and the reduced iron collected from the collector 840 to the main body 810. A circulation line CL connecting the collector 840 and the main body 810 may be further included. At this time, the collector 840 can be installed to be connected to the upper part of the main body 810 and connected to the discharge pipe (XL) through which the exhaust gas is discharged, and the reduced iron of the fine powder collected from the collector 840 is connected to the circulation line (CL). It can be re-supplied to the processing space of the main body 810 through. At this time, the circulation line (CL) may be directly connected to the processing space, but may also be connected to the above-mentioned reduced iron supply pipe (FL) to re-supply the fine reduced iron collected from the collector 840 to the processing space of the main body 810. .

As described above, the exhaust gas discharged from the dissolution unit 700 may be supplied to the treatment unit 800 and used to carbonize reduced iron. However, as described above, the exhaust gas discharged from the dissolution unit 700 is discharged at a high temperature of about 1,200°C or higher. Accordingly, in an embodiment of the present invention, the raw material may be preheated by utilizing the thermal energy of the exhaust gas.

As shown in FIG. 5, the raw material supply unit 100 may include a storage device 110, and the storage device 110 has a storage space for storing raw materials. Raw materials may be preheated in the storage space of the reservoir 110, and the raw materials preheated in the storage space may be supplied to the reduction unit 500. To this end, the raw material supply unit 100 may further include a preheating gas supplier 120 installed to supply preheating gas to the storage space of the reservoir 110. At this time, as shown in FIG. 5(a), the preheating gas supplier 120 is connected to the exhaust gas branch line (EDL) and directly supplies high temperature exhaust gas (E) with a temperature of about 1,200° C. or higher to the storage space to produce raw materials. can be preheated. In addition, as shown in FIG. 5(b), the preheating gas supplier 120 heats the external air (A) supplied to the storage space with the heat of exhaust gas having a temperature of 1,200°C or higher, and supplies the heated air to the storage space. It can be installed to preheat the raw materials. To this end, the preheating gas supplier 120 may be disposed to cross the exhaust gas branch line (EDL), that is, on the exhaust gas branch line (EDL), whereby the sensible heat of the exhaust gas passing through the branch line (EDL) is transferred to the outside. It can be transmitted to the air (A).

The molten iron manufacturing apparatus according to an embodiment of the present invention can produce reacted reduced iron by moving reduced iron and exhaust gas along each of the above-described pipes. The movement of reduced iron and exhaust gas can be controlled through valves (not shown) installed in pipes, and such valves can be installed in various locations to control the flow rate and flow rate of reduced iron and gas moving along each pipe. Of course.

Hereinafter, a method for manufacturing molten iron according to an embodiment of the present invention will be described. The method of manufacturing molten iron according to an embodiment of the present invention may be a method of manufacturing molten iron using the above-described molten iron manufacturing apparatus, and since the above-described content in relation to the molten iron manufacturing apparatus can be applied as is, description of overlapping content is omitted. I decided to do it.

Figure 6 is a diagram schematically showing a method for manufacturing molten iron according to an embodiment of the present invention.

Referring to FIG. 6, the method for producing molten iron according to an embodiment of the present invention includes a process of producing reduced iron (S100), a process of reacting the produced reduced iron with a processing gas (S200), and dissolving the reacted reduced iron to produce a molten product. It includes a process (S300) and a process (S400) of using at least a portion of the exhaust gas generated in the process of producing the melt as a processing gas to react with reduced iron. Here, each process can be continuously performed to manufacture molten iron, and of course, it may not correspond to a time-series relationship in which another process is performed after one process is completed.

The process of manufacturing reduced iron (S100) is performed by supplying raw materials and reducing gas to the reduction unit 500. That is, the process of manufacturing reduced iron (S100) may include a process of supplying raw materials to the reduction unit 500, a process of supplying reducing gas to the reduction unit 500, and a process of reducing the raw materials by reacting them with the reducing gas. there is.

The process of supplying raw materials is performed by the raw material supply unit 100, which is installed to supply raw materials to the reduction unit 500, supplying raw materials to the reduction unit 500. Here, the raw material may include iron ore, and the iron ore may include finely divided iron ore, that is, powdered iron ore, having a particle size greater than 0 mm and less than or equal to 8 mm. Meanwhile, the process of supplying raw materials may include a process of preheating the raw materials. In an embodiment of the present invention, the energy required for reduction can be minimized by supplying and reducing preheated raw materials, that is, iron ore.

The process of supplying the reducing gas is performed by the reducing gas supply unit 200 supplying the reducing gas to the reducing unit 500. Here, the reducing gas may include hydrogen gas, and hydrogen gas may be included in a ratio of 80 to 100% of the total reducing gas. The process of supplying the reducing gas is that the reducing gas supply unit 200 reduces the reduction gas to the reduction unit 500 through the reduction gas supply lines RL1 and RL2 that interconnect the reduction gas supply unit 200 and the reduction unit 500. This is done by supplying gas. At this time, in the process of supplying the reducing gas, the amount of reducing gas supplied to the reduction unit 500 is controlled to be in the range of more than 2 times and less than 3 times the amount required to reduce all the raw materials supplied to the reduction unit 500. It can be.

In the process of supplying the reducing gas, the reducing gas may be heated to a temperature of 800 to 1200° C. and then supplied to the reducing unit 500. When hydrogen gas is used as the reducing gas, reduced iron is produced by reacting the iron ore supplied to the reduction unit 500 with hydrogen gas. Since this reaction between iron ore and hydrogen gas is a strong endothermic reaction, the iron ore supplied to the reduction unit 500 reacts with hydrogen gas to produce reduced iron. The hydrogen gas can be heated to a temperature of 800°C or higher, more preferably 850°C or higher, and supplying the heated reducing gas can improve reaction efficiency.

In addition, the process of manufacturing reduced iron (S100) may further include a process of supplying a purge gas to the reduction unit 500. Here, the process of supplying the purge gas can be performed by the purge gas supply unit 400, which is installed to supply the purge gas to the reduction unit 500, supplying the purge gas to the reduction space through the purge gas supply line PL. there is. At this time, an inert gas such as nitrogen can be used as the purge gas.

The process of reducing raw materials by reacting them with a reducing gas involves the reducing unit 500 receiving raw materials from the raw material supply unit 100, receiving reducing gas from the reducing gas supply unit 200, and reacting the iron ore with the reducing gas to reduce it. You can. The reduction unit 500 may include a reduction furnace having a reduction space capable of producing reduced iron using a reduction gas. The reduction furnace may be provided as a single unit, but low-grade iron ore or powder with a low iron content may be used. As mentioned above, in order to effectively reduce iron ore, a plurality of reduction furnaces may be connected to sequentially move raw materials to produce reduced iron.

Meanwhile, in the process of reducing raw materials by reacting them with reducing gas, a large amount of by-products are generated in addition to reduced iron. By-products generated and discharged from the reduction unit 500 may include water vapor generated by the reaction of iron ore and hydrogen gas, and may include hydrogen gas that has not reacted with the raw material and nitrogen gas supplied as a purge gas. In addition, dust, etc. generated in the reduction unit 500 may be included in by-products and discharged, and the by-products may move along the flow of reducing gas within the reduction unit 500 and be discharged from the reduction furnace.

In this way, by-products discharged from the reduction furnace can be used to produce hydrogen gas. That is, the molten iron manufacturing method according to the embodiment of the present invention may further include a process of collecting by-products generated in the process of manufacturing reduced iron and a process of extracting hydrogen gas from the collected by-products. As described above, the by-products discharged from the reduction unit 500 include water vapor, hydrogen gas, nitrogen gas, and dust, and the reduction unit 500 is provided with a supply of by-products discharged from the reduction unit 500. An extraction unit 600 is installed. Here, dust may be removed before the by-products are supplied to the extraction unit 600 or within the extraction unit 600. The extraction unit 600 may extract hydrogen gas from by-products supplied through the by-product supply line BL using a pressure swing adsorption method.

Hydrogen gas extracted during the process of extracting hydrogen gas can be used for various purposes. However, the reduction unit 500 uses hydrogen gas to reduce the raw material, that is, iron ore, and the hydrogen gas is used in a large amount, more than twice the amount required to reduce all the raw materials supplied to the reduction unit 500. Since it is a very expensive gas, the hydrogen gas extracted from the extraction unit 600 can be reused as a reducing gas to reduce iron ore in order to reduce costs through resource recycling. To this end, the method for producing molten iron according to an embodiment of the present invention can be used to reduce iron ore by supplying extracted hydrogen gas as a reducing gas during the process of producing reduced iron (S100). Meanwhile, the residue that is not extracted and discharged during the process of extracting hydrogen gas may be supplied to the reduction unit 500 as a purge gas. The water vapor in the residue is a reaction product generated by the reaction between iron ore, which is a raw material, and hydrogen gas in the reducing gas. Since it has low reactivity with the iron ore and the reducing gas, it can be supplied to the reduction unit 500 as a purge gas. Additionally, when water vapor is supplied to the reduction unit 500 as a purge gas, the heat of the water vapor can be utilized for the reduction reaction, thereby saving the energy required for the reduction reaction.

In the process of reacting with the processing gas (S200), the reduced iron produced in the reduction unit 500 reacts with the processing gas. Here, the processing gas includes a gas containing a carbon component, and the process of reacting with the processing gas (S200) may include carbonizing at least a portion of the reduced iron produced in the reduction unit 500.

That is, as described above, when the reduced iron produced in the reduction unit 500 is dissolved without any additional treatment, the melting point of the reduced iron is very high and a lot of energy is required to dissolve it. In contrast, when the reduced iron is carbonized, the melting point is reduced to several hundred. It can be lowered by more than ℃. Accordingly, in the method for manufacturing molten iron according to an embodiment of the present invention, reduced iron is reacted with a processing gas, and the reacted reduced iron, that is, iron carbide, is supplied to the melting unit 700 to be dissolved, thereby minimizing the amount of energy used for melting. At this time, the processing gas may include a gas containing carbon.

Here, in the process of reacting with the processing gas (S200), reduced iron can be reacted with the processing gas without separate heat treatment. That is, the reduced iron produced in the reduction unit 500 is discharged at a high temperature of, for example, 600 to 800° C., and the discharged reduced iron is directly supplied to the treatment unit 800 without going through a separate heat treatment device. In addition, since high temperature exhaust gas of approximately 1,200°C or higher is supplied to the processing space, the processing space can maintain a temperature of 600 to 800°C even taking into account the heat loss of reduced iron during the transfer process. Accordingly, in the process of reacting with the processing gas (S200), the produced reduced iron can be reacted with the processing gas at a temperature of 600 to 800°C, and at the beginning of the process or when additional temperature increase is necessary, the processing space is heated through the heater 820. Can be optionally heated.

Reduced iron can be carbonized by reacting according to the above-mentioned reaction equation when the processing space is maintained at a temperature of 600 to 800° C. and the partial pressure of carbon monoxide and carbon dioxide in the processing space satisfies specific conditions. In other words, when reduced iron and exhaust gas at high temperature are supplied to the treatment space and the treatment space maintains a temperature of 600 to 800°C, the partial pressure of carbon monoxide (Pco) is equal to the partial pressure of carbon monoxide (Pco) and the partial pressure of carbon dioxide (Pco ₂₎ . ), when it has a value of about 90% or more of the combined value (Pco + Pco ₂ ), it reacts and is carbonized according to the above-mentioned reaction formula.

Here, in order to carbonize reduced iron by reacting it with a processing gas, the molten iron manufacturing method according to an embodiment of the present invention includes a process (S400) of using at least a portion of the exhaust gas generated during manufacturing the molten material as a processing gas to react with the reduced iron. It can be included. That is, the process of using as a processing gas (S400) converts at least a portion of the exhaust gas generated in the process of producing the melt (S300) into a processing gas that reacts with the reduced iron in the process of reacting the produced reduced iron with the processing gas (S200). use. As described above, the melting unit 700 may include electric furnaces 710 and 720 having a melting space that can melt reduced iron using electric heat. In this dissolution unit 700, a recarburizing agent containing a carbon component is introduced to adjust the carbon content of the melt produced by dissolving reduced iron. Meanwhile, at least partially unreduced raw materials, that is, partially reduced reduced iron or iron ore, may be supplied to the dissolution unit 700. In this way, at least a part of the unreduced raw material has an oxygen component, and the oxygen component reacts with the carbon component of the recarburizer within the dissolution space. Accordingly, in the dissolving unit 700, exhaust gas containing carbon monoxide gas, that is, exhaust gas having a high carbon monoxide concentration (CO-rich), is discharged while dissolving the reduced iron. In this way, the exhaust gas discharged from the dissolution unit 700 is discharged at a high temperature of about 1,200° C. or higher.

At this time, the melting unit 700 is an electric furnace (710, 720) capable of dissolving reduced iron, that is, an Electric Smelting Furnace (ESF) that is immersed in slag formed in the electric furnace body 710 and can dissolve reduced iron with slag resistance heat. ) or SAF (Submerged Arc Furnace). Such electric furnaces (710, 720) have a very low carbon dioxide content in the exhaust gas, and have a high carbon monoxide concentration due to the reaction between the oxygen component of the unreduced raw material and the carbon component of the recarburizer. Therefore, the partial pressure of carbon monoxide (Pco) discharged from the electric furnaces 710 and 720 is about 90% or more of the sum of the partial pressure of carbon monoxide (Pco) and the partial pressure of carbon dioxide (Pco ₂ ) (Pco + Pco ₂ ). value, it is possible to effectively carbonize reduced iron under temperature conditions of 600 to 800°C.

Meanwhile, in the process of reacting with the processing gas (S200), supplemental gas having at least some of the same components as the exhaust gas may be used as the processing gas. As described above, the supplementary gas supply unit 900 may supply supplementary gas, that is, a carbon-containing gas having at least some of the same components as the exhaust gas, to the processing unit 800, and the supplementary gas supply unit 900 may supply supplementary gas supply line SL. Carbon-containing gas can be supplied to the processing unit 800 through. Here, the supplementary gas supply line (SL) is connected to the exhaust gas supply line (EL) to supply supplementary gas along with the exhaust gas, and the supplementary gas is natural gas with a carbon component and biomass gas gasified from biomass. It may include at least one of:

At this time, in the process of reacting with the treatment gas (S200), most of the reduced iron supplied to the treatment space reacts with the exhaust gas and is supplied to the dissolution unit 700, but the reduced iron in fine powder does not react sufficiently with the exhaust gas, and flows by the exhaust gas to form the exhaust gas. It may leak to the outside from the treatment space.

Accordingly, the method for manufacturing molten iron according to an embodiment of the present invention may further include a process of collecting reduced iron flowing out from a processing space in which reduced iron reacts with a processing gas and a process of supplying the collected reduced iron to the processing space.

Here, the process of collecting the reduced iron flowing out is performed through a collector 840 connected to the main body 810 to collect the reduced iron flowing out from the main body 810, and the collector 840 is located at the upper part of the main body 810. It can be installed to be connected to the discharge pipe (XL) through which exhaust gas is discharged. In addition, in the process of supplying the collected reduced iron to the processing space, the fine reduced iron collected from the collector 840 is re-supplied to the processing space of the main body 810 through the circulation line (CL). At this time, the circulation line (CL) It may be directly connected to the processing space, but may also be connected to the above-mentioned reduced iron supply pipe (FL) to re-supply the fine reduced iron collected from the collector 840 to the processing space of the main body 810.

The process of producing a melt (S300) is performed by the dissolving unit 700 receiving reacted reduced iron, that is, iron carbide, from the processing unit 800 and dissolving the supplied iron carbide. That is, the melting unit 700 can receive finely divided or agglomerated iron carbide from the processing unit 800 and heat it to dissolve it. Additionally, the process of producing a melt (S300) may be performed by the melting unit 700 receiving iron carbide from the processing unit 800 and melting the supplied iron carbide using electric heat. At this time, the melting unit 700 may include an electric furnace having a melting space that can melt iron carbide using electric heat. Such an electric furnace may include an electric furnace body having a dissolution space and an electrode at least partially disposed in the dissolution space to generate electric heat, and the dissolution unit 700 may provide electric power to the electrode when reduced iron is charged into the dissolution space. The iron carbide can be dissolved by applying .

Here, the process of manufacturing the melt (S300) may include the process of introducing a recarburizing agent into the melting unit 700, that is, the melting space of the electric furnace. In the melting unit 700, a recarburizing agent containing a carbon component is introduced to adjust the carbon content of the melt produced by dissolving reduced iron. Additionally, a recarburizing agent may be added to generate a large amount of slag when dissolving the melt. The electrode 720 can generate resistance heat by being immersed in the slag, and iron carbide can be more easily dissolved by the generated resistance heat. At this time, since the iron carbide supplied from the processing unit 800 already contains a large amount of carbon components, the amount of recarburizing agent used can be minimized in the process of producing the melt (S300).

Meanwhile, as described above, while dissolving reduced iron in the dissolving unit 700, exhaust gas containing carbon monoxide gas, that is, exhaust gas having a high carbon monoxide concentration (CO-rich) and a temperature of about 1,200° C. or higher, is discharged. Accordingly, the process of preheating the raw material described above can be performed using the exhaust gas discharged from the melting unit 700, that is, the exhaust gas discharged during the process of manufacturing the melt, which will be described later. Since the exhaust gas discharged from the dissolution unit 700 is discharged at a high temperature of about 1,200° C. or higher, the raw material can be preheated by utilizing the heat energy of the exhaust gas.

To explain this in more detail, the process of preheating the raw material may include a process of spraying a portion of the exhaust gas discharged from the dissolution unit 600 directly onto the raw material. The process of supplying raw materials supplies the raw materials stored in the storage space of the reservoir 110 to the reduction unit 500, so that preheating gas can be supplied to the storage space of the reservoir 110. A preheating gas supplier 120 may be installed. At this time, the process of preheating the raw materials may be performed by spraying high-temperature exhaust gas with a temperature of about 1,200°C or higher from the preheating gas supplier 120 to the raw materials stored in the storage space. In addition, the preheating gas supplier 120 may preheat the raw materials by spraying heated external air onto the raw materials stored in the storage space. In this case, the process of preheating the raw materials involves the preheating gas supplier 120 blowing external air to a temperature of 1,200°C or higher. The raw material can also be preheated by heating it with the heat of the exhaust gas having a temperature and supplying the heated air to the storage space.

As such, according to an embodiment of the present invention, the melting point of the reduced iron can be lowered by reacting the exhaust gas generated during the process with the reduced iron, thereby minimizing the amount of energy used to dissolve the reduced iron.

In addition, by directly reacting reduced iron produced at high temperature with high temperature exhaust gas, equipment and resources required for the reaction can be minimized.

In addition, energy can be efficiently recovered by using the sensible heat of the high-temperature exhaust gas for preheating raw materials and producing hydrogen gas.

In the above, preferred embodiments of the present invention have been described and illustrated using specific terms, but such terms are only for clearly describing the present invention, and the embodiments of the present invention and the described terms are in accordance with the technical spirit of the following claims. It is obvious that various changes and changes can be made without departing from the scope. These modified embodiments should not be understood individually from the spirit and scope of the present invention, but should be regarded as falling within the scope of the claims of the present invention.

100: raw material supply unit 200: reducing gas supply unit
300: heating unit 400: purge gas supply unit
500: reduction section 600: extraction section
700: dissolution unit 800: processing unit

Claims (20)

A reduction unit capable of producing reduced iron;
A dissolving portion capable of dissolving reduced iron; and
A processing unit capable of receiving reduced iron from the reduction unit and receiving exhaust gas discharged from the dissolution unit, and reacting the supplied reduced iron with the exhaust gas to supply the reacted reduced iron to the dissolution unit. Manufacturing facilities. In claim 1,
It further includes an exhaust gas supply line installed to connect the dissolving unit and the processing unit,
The reduction unit includes a reduction furnace having a reduction space capable of producing reduced iron by receiving reduction gas,
The melting unit is connected to the exhaust gas supply line, and has a melting space in which reduced iron supplied from the processing unit can be melted using electric heat. A molten iron manufacturing facility comprising a. In claim 2,
The processing unit,
a main body having a processing space;
a reduced iron inlet provided in the main body to allow reduced iron to flow into the processing space; and
An exhaust gas inlet provided in the main body and connected to the exhaust gas supply line to allow exhaust gas to flow into the processing space,
A molten iron manufacturing facility wherein the exhaust gas inlet is provided at a lower position than the reduced iron inlet. In claim 3,
The processing unit,
A molten iron manufacturing facility further comprising a heater installed in the main body to heat the processing space. In claim 3,
The processing unit,
A collector connected to the main body to collect reduced iron flowing out from the main body; and
Molten iron manufacturing equipment further comprising a circulation line connecting the collector and the main body so that the reduced iron collected from the collector can be supplied to the main body. In claim 3,
The processing unit,
Molten iron manufacturing equipment further comprising: a supplementary gas supply unit connected to the main body to supply supplementary gas having at least some of the same components as the exhaust gas to the processing space. In claim 2,
A raw material supply unit having a storage space for storing raw materials and installed to supply the raw materials stored in the storage space to the reduction space; and
A molten iron manufacturing facility further comprising an exhaust gas branch line branched from the exhaust gas supply line and capable of supplying a portion of the exhaust gas discharged from the electric furnace to the raw material supply unit. In claim 7,
The exhaust gas branch line is connected to the raw material supply unit to directly supply exhaust gas to the storage space or to transfer heat of the exhaust gas to air supplied to the storage space. In claim 3,
a purge gas supply line connected to the reduction furnace to supply purge gas to the reduction space; and
A purge gas branch line branched from the purge gas supply line and capable of supplying a portion of the purge gas supplied to the reduction space to the processing space. Process of producing reduced iron;
A process of reacting the produced reduced iron with a processing gas;
A process of dissolving the reacted reduced iron to produce a molten product; and
A method of producing molten iron comprising: using at least a portion of the exhaust gas generated in the process of producing the molten material as a processing gas to react with reduced iron. In claim 10,
The process of producing the reduced iron is,
A process of preheating raw materials using the exhaust gas; and
A method of manufacturing molten iron including a process of reducing the preheated raw material by reacting it with a reducing gas. In claim 11,
The process of preheating the raw materials is,
A method of manufacturing molten iron comprising: spraying the exhaust gas onto the raw material, or spraying air heated by receiving heat from the exhaust gas onto the raw material. In claim 11,
A method of producing molten iron, wherein the raw material includes powdered iron ore having a particle size of more than 0 mm and less than or equal to 8 mm. In claim 10,
The processing gas includes a gas containing a carbon component,
The process of reacting with the processing gas is,
A method of producing molten iron, including a process of carbonizing at least a portion of the reduced iron. In claim 10,
The process of reacting the reduced iron with the processing gas is,
A method of manufacturing molten iron in which the reduced iron is reacted with a processing gas without any additional heat treatment. In claim 10,
The process of reacting the reduced iron with the processing gas is,
A method of producing molten iron comprising: reacting the produced reduced iron with a processing gas at a temperature of 600 to 800°C. In claim 10,
A process of collecting reduced iron flowing out from a processing space where the reduced iron reacts with a processing gas; and
A method of manufacturing molten iron further comprising: supplying the collected reduced iron to the processing space. In claim 17,
The process of producing the reduced iron is,
Including a process of supplying a purge gas to the reduction space for producing the reduced iron,
The process of reacting the reduced iron with the processing gas is,
A method of manufacturing molten iron comprising: supplying a portion of the purge gas supplied to the reduction space to the processing space. In claim 10,
The process of using the processing gas is,
A method of producing molten iron using the exhaust gas and a supplementary gas having at least some of the same components as the exhaust gas as a processing gas. In claim 19,
The exhaust gas includes carbon monoxide gas,
The supplementary gas includes at least one of natural gas and biomass gas.

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