KR20240098529A - Apparatus for manufacturing compacted iron, apparatus for manufacturing molten iron, method for manufacturing compacted iron and, method for manufacturing molten iron - Google Patents

Abstract

An embodiment of the present invention is a compacted material manufacturing apparatus including a compacted material production unit capable of producing compacted material, wherein the compacted material production section includes a torrefaction machine and a semiconductor having a space for heating and torrefaction biomass raw materials. It may include a molding machine that can mix the biomass raw material torrefied in the carbonizer and reduced iron and mold it into a compacted material.
Therefore, according to the embodiments of the present invention, a compacted material with an improved carbon (C) content can be manufactured, and thus the reactivity of the compacted material can be improved. Additionally, the compacted material according to the embodiment may be used as an iron source for producing molten iron. Therefore, the amount of coke input for melting the iron source can be reduced. In addition, by using compacted materials containing biomass raw materials as an iron source, worsening of atmospheric pollution due to carbon dioxide (CO ₂ ) can be suppressed or prevented.

Description

Compacted material manufacturing equipment, molten iron manufacturing equipment, method of manufacturing compacted material, and method of manufacturing molten iron

The present invention relates to a compacted material manufacturing apparatus, a molten iron manufacturing facility, a method for producing compacted material, and a method for producing molten iron, and more specifically, to the production of a compacted material capable of producing a compacted material capable of suppressing the generation of environmental pollutants. It relates to devices, molten iron production facilities, methods for producing compacted materials, and methods for producing molten iron.

In a blast furnace, iron ore is reduced and melted to produce molten iron. That is, iron ore, which is an iron source, and coke, which is used as a heat source and reducing agent, are introduced into the upper part of the blast furnace, and high-temperature gas is supplied to the lower part of the blast furnace. Accordingly, the coke introduced into the blast furnace is burned by high-temperature gas, and the iron ore is reduced and melted by the heat and carbon monoxide (CO) generated at this time, producing molten iron.

Meanwhile, when iron ore is reduced by carbon monoxide (CO), a large amount of carbon dioxide (CO ₂ ) is generated, which causes air pollution. Therefore, in order to reduce the generation of carbon dioxide (CO ₂ ), reduced iron, which has been reduced in advance by using by-product gas, etc., is used as a substitute for iron ore. In other words, a method is being used to produce reduced iron by reducing powdered iron ore, and then inputting the reduced iron into agglomerated material as a substitute for iron ore, that is, as an alternative iron source. However, since reduced iron is manufactured by already reducing iron ore, it has a problem of low reactivity when introduced into a blast furnace. And when reactivity is low, more heat energy is required to react and melt the compacted material. Therefore, when reduced iron compacted material with low reactivity is input as a substitute for iron ore, the input amount of coke used as a heat source and reducing agent is increased. However, since carbon dioxide (CO ₂ ) is generated during combustion of coke, there is a problem in that the amount of carbon dioxide (CO ₂ ) generated increases as the amount of coke input increases.

Therefore, there is a need to develop a highly reactive substitute for coke without worsening environmental pollution.

Korean registered patent KR 10-0864459

The present invention provides a compacted body manufacturing apparatus, a molten iron manufacturing facility, a compacted body manufacturing method, and a molten iron manufacturing method capable of producing a compacted body in which the generation of environmental pollutants is suppressed.

The present invention provides a compacted material manufacturing apparatus capable of producing a compacted material with improved reactivity, a molten iron manufacturing facility, a method for producing a compacted material, and a method for producing molten iron.

An embodiment of the present invention is a compacted material manufacturing apparatus including a compacted material manufacturing unit capable of producing a compacted material, wherein the compacted material manufacturing unit includes a torrefaction device provided with a space for heating and torrefaction biomass raw materials; and a molding machine capable of mixing the biomass raw material torrefied in the torrefaction machine and the reduced iron and forming it into a compacted material.

The first compacted material can be supplied from the compacted material manufacturing unit, and the first compacted material is reacted with a reaction gas to convert the first compacted material into a second compacted material containing iron carbide (Fe ₃ C). It may include a reaction unit installed to enable the reaction.

The compacted material manufacturing unit includes a reduced iron storage unit that stores the reduced iron; and a biomass storage device that receives and stores torrefied biomass raw materials from the torrefaction device, wherein the molding machine is installed to receive reduced iron and biomass raw materials from the reduced iron storage device and the biomass storage device. It can be.

The compacted material manufacturing unit includes a carbon-containing by-product storage device capable of storing at least one of a carbon-containing by-product generated in a coke manufacturing device, a carbon-containing by-product generated in a coke extinguishing device, and a carbon-containing by-product generated in a melting device for producing molten iron, The molding machine may be installed to receive carbon-containing by-products from the carbon-containing by-product storage unit.

A molten iron production facility according to an embodiment of the present invention includes a reduced iron production device capable of producing reduced iron by reducing raw materials containing iron ore; A compacted material manufacturing device installed to receive reduced iron from the reduced iron manufacturing device and to produce a compacted material by mixing the reduced iron with a biomass raw material; and a melting device installed to receive a compacted material from the compacted material manufacturing device and to melt the compacted material to produce molten iron.

The compacted body manufacturing apparatus includes a torrefaction machine capable of torrefaction of the biomass raw material, and a molding machine that mixes the torrefied biomass raw material produced in the torrefaction machine and reduced iron and produces a compacted body using the mixture. A compacted material manufacturing unit comprising: and a reaction unit installed to receive the compacted substance from the compacted substance manufacturing unit and to react the compacted substance with the reaction gas to increase the content of iron carbide (Fe ₃ C).

It may include a reaction gas supply device installed to recover by-product gas generated when torrefaction of biomass raw materials in the torrefaction unit and supply it to the reaction unit.

The reaction gas supply device includes a gas recovery unit installed to recover by-product gas generated from the torrefaction reactor; a heating unit installed in the gas recovery unit to heat the by-product gas passing through the gas recovery unit; It may include a gas supply unit installed to supply the by-product gas heated in the heating unit to the reaction unit.

The method for producing a compacted material according to an embodiment of the present invention is,

Process of producing reduced iron; Process of preparing biomass raw materials; A process of increasing the content of fixed carbon by heating the biomass raw material; A process of preparing a mixture by mixing the reduced iron and heated biomass raw materials; And a process of producing a compacted body by molding the mixture; may include.

The biomass raw material includes at least one of a lignocellulosic biomass raw material and a herbaceous biomass raw material, and the lignocellulosic biomass raw material includes chips, charcoal, briquettes, and pellets containing wood ( pellet), and the herbaceous biomass raw material may include at least one of rice straw and rice husk.

In preparing the mixture, it is preferable to mix so that the content of fixed carbon is 2% by weight to 5% by weight with respect to the entire compacted material.

The process of increasing the content of fixed carbon by heating the biomass raw material includes a process of torrefaction of the biomass raw material, and in preparing the mixture, the torrefied biomass raw material of the entire mixture is It is preferable to mix so that it exceeds 0% by weight and does not exceed 10% by weight.

The process of increasing the content of fixed carbon by heating the biomass raw material includes the process of torrefaction of the biomass raw material, and the process of preparing the mixture includes the process of further mixing carbon-containing by-products generated during the steelmaking process. In preparing the mixture, it is preferable to mix the total mixture so that the combined content of the torrefied biomass raw material and the content of the carbon-containing by-product is more than 0% by weight and 10% by weight or less. .

In preparing the mixture, it is preferable to mix so that the content of the torrefied biomass raw material is greater than the content of the carbon-containing by-product in the entire mixture.

The first compacted body manufactured by molding is reacted with a reaction gas to convert the iron (Fe) contained in the metallic iron and iron oxide contained in the first compacted body into iron carbide (Fe ₃ C), thereby producing iron carbide ( It may include a process of producing a second compacted material containing Fe ₃ C).

A method for producing molten iron according to an embodiment of the present invention includes a process of producing compacted iron using a mixture containing reduced iron and torrefied biomass raw material; And it may include a process of injecting the compacted material into a melting device and melting the compacted material.

The process of producing the compacted material includes reacting the compacted material with a reaction gas containing hydrocarbon to produce a compacted material containing iron carbide (Fe ₃ C), and introducing the compacted material into a melting device. In doing so, the compacted material containing iron carbide (Fe ₃ C) may be introduced into the melting device.

The reaction gas may include by-product gas generated when torrefaction of biomass raw materials.

It includes the process of introducing iron ore into the melting device, and in melting the compacted material, the iron ore may be melted together.

According to embodiments of the present invention, by adding biomass to reduced iron to produce a compacted body, a compacted body with an improved carbon (C) content can be manufactured, and thus the reactivity of the compacted body can be improved.

In addition, as a compacted material with improved reactivity is used as a substitute for the iron source, there is no need to increase the amount of coke used as a heat source when producing molten iron. Therefore, it is possible to prevent the amount of carbon dioxide (CO ₂ ) generated due to an increase in the amount of coke input during the production of molten iron.

Additionally, biomass is not a material that generates environmental pollutants, as is known. In other words, carbon dioxide (CO ₂ ) released from biomass is the carbon dioxide (CO ₂ ) absorbed by plants, which are raw materials, during photosynthesis. Accordingly, carbon dioxide (CO ₂ ) emitted from biomass is not considered an environmental pollutant. Therefore, by using compacted material containing biomass raw materials as a substitute for coke, worsening of atmospheric pollution due to carbon dioxide (CO ₂ ) can be suppressed or prevented.

1 is a block diagram conceptually showing a molten iron manufacturing facility including a compacted material manufacturing apparatus according to an embodiment of the present invention.
FIG. 2 is a block diagram showing each configuration of the reduced iron production device, compacted material supply device, and reaction gas supply device briefly shown in FIG. 1.
Figure 3 shows the results of an experiment on the reduction rate of compacted materials according to comparative examples and examples.
Figure 4 is a flowchart showing a method of manufacturing molten iron using a molten iron manufacturing facility according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more 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. These embodiments only serve to ensure that the disclosure of the present invention is complete and to fully convey the scope of the invention to those skilled in the art. This is provided to inform you. The drawings may be exaggerated to explain embodiments of the present invention, and like symbols in the drawings refer to like elements.

1 is a block diagram conceptually showing a molten iron manufacturing facility including a compacted material manufacturing apparatus according to an embodiment of the present invention. FIG. 2 is a block diagram showing each configuration of the reduced iron production device, compacted material supply device, and reaction gas supply device briefly shown in FIG. 1.

Referring to FIG. 1, the molten iron production facility according to an embodiment of the present invention is a reduced iron production device 1000 that produces reduced iron by reducing raw materials including iron ore, using raw materials including biomass and reduced iron. Compacted material manufacturing apparatus (2000) for producing compacted material containing iron carbide (Fe ₃ C) (hereinafter referred to as compacted material containing iron carbide (Fe ₃ C)), melting the iron source and compacted material containing iron carbide (Fe ₃ C) to produce molten iron It may include a melting device 3000 for manufacturing.

In addition, the molten iron manufacturing facility includes a compacted material supply device 4000 that supplies iron carbide (Fe ₃ C)-containing compacted material produced in the compacted material manufacturing device 2000 to the melting device 3000, and a compacted material containing iron carbide (Fe ₃ C)-containing compacted material. It includes a reaction gas supply device (6000) that supplies a reaction gas for producing a sieve to the compacted material production device (2000).

The raw material supplied to the reduced iron manufacturing apparatus 1000 may be a raw material containing iron ore. And the raw material containing iron ore may be in the form of fine particles or powder. In other words, the raw material containing iron ore may be powdered ore, that is, iron ore.

The reduced iron manufacturing apparatus 1000 produces reduced iron by reducing raw materials containing iron ore using a reducing gas containing carbon monoxide (CO). As shown in FIG. 2, this reduced iron manufacturing apparatus 1000 includes a reduction unit 1100 that reduces raw materials containing iron ore to produce reduced iron, and a heating unit that heats reduction gas to be supplied to the reduction unit 1100. (1200), a heat exchange unit 1300 for heat-exchanging the exhaust gas discharged from the reduction unit 1100, and a vibration control unit 1400 for removing fine particles, that is, dust, from the exhaust gas discharged from the heat exchange unit 1300. .

In addition, the reduced iron manufacturing apparatus 1000 includes a reducing gas supply unit 1210 that supplies reduced gas heated in the heating unit 1200 to the reduction unit, and an oxygen supply unit that supplies gas containing oxygen (O ₂ ) to the heating unit 1200. A supply unit 1220, an exhaust unit 1110 that transfers the exhaust gas discharged from the reduction unit 1100 to the heat exchange unit, an exhaust gas transfer unit 1310 that transfers the exhaust gas discharged from the heat exchange unit 1300 to the vibration control unit, and a vibration control unit 1400. ), a discharge unit 1410 that discharges to the outside a part of the exhaust gas from which dust has been removed, and a first circulation unit 1420a that supplies another part of the exhaust gas from which dust has been removed in the vibration removal unit 1400 back to the heat exchange unit 1300. ), the second circulation unit (1420b), which supplies the heated exhaust gas back to the heat exchange unit (1300) to the heating unit (1200), and the exhaust gas from which dust is removed by being installed on the extension path of the second circulation unit (1420b) It may include a separation unit 1500 that separates carbon dioxide (CO ₂ ) from.

Here, the reducing gas supply unit 1210, the oxygen supply unit 1220, the exhaust unit 1110, the exhaust gas transfer unit 1310, the discharge unit 1410, and the first and second circulation units 1420a and 1420b each have gas inside them. It may be configured to include a pipe provided with a passage or flow path through which .

The reduction unit 1100 may include a reduction furnace that produces reduced iron by reacting the reducing gas and the raw materials while flowing the raw materials including iron ore with the reducing gas. Additionally, a single reduction reactor may be provided, but a plurality of reduction reactors may be provided to effectively reduce low-grade iron ore or powdered iron ore with low iron content. Hereinafter, it will be described as an example that the reduction unit 1100 includes four reduction furnaces 1100a to 1100d. The four reduction furnaces 1100a to 1100d may be installed to have different heights, and may be arranged so that the height increases or decreases in one direction. Hereinafter, the reduction furnace located at the bottom among the four reduction furnaces (1100a to 1100d) is referred to as the first reduction furnace (1100a), and sequentially from the first reduction furnace (1100a) to the second reduction furnace (1100b) and the third reduction furnace. They are named furnace (1100c) and fourth reduction furnace (1100d). Here, the first reduction furnace 1100a is a reduction furnace connected to the reduction gas supply unit 1210 and supplied with a reduction gas, and the fourth reduction reactor 1100d is a reduction furnace into which raw materials including iron ore are supplied from the outside.

When a plurality of reduction furnaces are provided, the reduction unit 1100 may include a plurality of raw material transfer pipes and a plurality of gas transfer pipes installed to connect the plurality of reduction furnaces. For example, if the reduction unit includes four reduction furnaces (1100a to 1100d), the reduction unit 1100 may include three raw material transfer pipes (1111a to 1111c) and three gas transfer pipes (1112a to 1112c). there is.

That is, the first raw material transfer pipe 1111a is installed between the fourth reduction reactor 1100d and the third reduction reactor 1100c, and the second raw material transfer pipe 1111a is installed between the third reduction reactor 1100c and the second reduction reactor 1100b. A raw material transfer pipe 1111b is installed, and a third raw material transfer pipe 1111c is installed between the second reduction furnace 1100b and the first reduction furnace 1100a. Accordingly, raw materials containing iron ore are input into the fourth reduction reactor (1100d) and undergo primary reduction, and the raw materials first reduced in the fourth reduction reactor (1100d) are subjected to third reduction through the first raw material transfer pipe 1111a. The raw material supplied to the furnace 1100c and secondaryly reduced in the third reduction furnace 1100c is supplied to the second reduction furnace 1100b through the second raw material transfer pipe 1111b. The thirdly reduced raw material is supplied to the first reduction furnace (4100a) through the third raw material transfer pipe (1111c). And the fourth reduced raw material, that is, reduced iron, in the first reduction furnace (1100a) is supplied to the melting device (3000).

Additionally, gas transfer pipes 1112a to 1112c are installed to interconnect the first to fourth reduction reactors 1100a to 1100d. That is, a first gas transfer pipe 1112a is installed between the first reduction furnace 1100a and the second reduction furnace 1100b, and a second gas transfer pipe 1112a is installed between the second reduction furnace 1100b and the third reduction furnace 1100c. A gas transfer pipe 1112b is installed, and a third gas transfer pipe 1112c is installed between the third reduction reactor 1100c and the fourth reduction reactor 1100d. Accordingly, the reduction gas supplied to the first reduction reactor (1100a) is sequentially transferred to the second to fourth reduction reactors (1100b to 1100d) through the first to third gas transfer pipes (1112a to 1112c). That is, the reduction gas supplied to the first reduction reactor (1100a) is supplied to the second reduction reactor (1100b) through the first gas transfer pipe 1112a, and the reduction gas supplied to the second reduction reactor (1100b) is It is supplied to the third reduction reactor (1100c) through the second gas transfer pipe (1112b), and the reduction gas supplied to the third reduction reactor (1100c) is supplied to the fourth reduction reactor (1100d) through the third gas transfer pipe (1112c). is supplied as At this time, the gas supplied to the second reduction reactor (1100b), the third reduction reactor (1100c), and the fourth reduction reactor (1100d) through the first to third gas transfer pipes (1112a to 1112c) is the first reduction reactor (1100a). ) may include not only the reduction gas supplied to the gas, but also the gas generated during the reduction reaction in each reduction furnace (1100a to 1100d).

In the above, it was explained as an example that four reduction furnaces (1100a to 1100d) are provided. However, the number of reduction reactors is not limited to 4 and can be varied to less than 4 or more than 4.

Each of the plurality of reduction furnaces 1100a to 1100d includes a container having an internal space (reduction space) that can accommodate raw materials and reduce the raw materials, and a plurality of holes through which a reducing gas can pass, It may include a dispersing member installed inside. In addition, each of the plurality of reduction furnaces 1100a to 1100d may further include a cyclone at least partially installed inside the vessel to collect fine powder.

In addition, some of the first to fourth reduction furnaces 1100a to 1100d may include burners that generate flames. At this time, the burner is preferably provided in reduction furnaces located at both ends of the first to fourth reduction furnaces 1100a to 1100d, that is, in reduction furnaces other than the first and fourth reduction furnaces 1100a to 1100d. For example, a burner may be provided in at least one of the second and third reduction furnaces 1100b and 1100c. Of course, all of the first to fourth reduction furnaces 1100a to 2100d may be equipped with burners. Additionally, at least one of the first and fourth reduction furnaces 1100a and 1100d disposed at both ends may be provided with a burner.

The heating unit 1200 heats the reducing gas to be supplied to the reducing unit 1100. To be more specific, in the compacted material manufacturing apparatus 2000, gas containing carbon monoxide (CO) and hydrogen (H) is generated in the process of manufacturing iron carbide-containing compacted material, and this gas is used as a reducing gas. Accordingly, the gas generated in the compacted material manufacturing apparatus 2000 is recovered and supplied to the heating unit 1200. And the heating unit 1200 heats the gas supplied from the compacted material manufacturing apparatus 2000. In this way, since the gas generated in the compacted material manufacturing device 2000 is used as a reducing gas supplied to the reduction unit 1100, the gas generated in the compacted material manufacturing device 2000 and supplied to the heating unit 1200 is 'reduced'. It can be named ‘gas’.

The heating unit 1200 may be a means for heating the reducing gas by combustion or partial combustion of the reducing gas. For example, the heating unit 1200 may include a main body that can accommodate reducing gas and a burner installed to be inserted into the main body to generate a flame inside the main body. Here, the burner may be a means of creating a flame by generating a spark through, for example, discharge. In addition, since the supply of oxygen (O ₂ ) is required for combustion of the reducing gas, an oxygen supply unit 1220 capable of supplying a gas containing oxygen (O ₂ ) may be connected to the main body of the heating unit 1200. Here, one end of the oxygen supply unit 1220 may be connected to a storage unit in which gas containing oxygen is stored, and the other end may be connected to the main body. Accordingly, gas containing oxygen can be supplied into the interior of the main body. The gas containing oxygen may be, for example, air. Of course, the gas containing oxygen is not limited to this and may be pure oxygen gas.

As described above, the heating unit 1200 heats the reducing gas supplied inside by burning or partially burning the reducing gas. This is briefly explained below. The reducing gas generated in the compacted material manufacturing apparatus 2000 is supplied to the main body of the heating unit 1200, and a gas containing oxygen (O ₂ ) is supplied into the main body using the oxygen supply unit 1220. Then, the burner is operated to generate a flame. Accordingly, the reducing gas supplied into the main body is partially burned and heated. At this time, the heating unit 1200 heats the reducing gas so that the temperature is 800°C or higher, preferably 800°C or higher and 850°C or lower.

In the above, it was explained that the heating unit 1200 receives and heats the reducing gas generated by the compacted material manufacturing apparatus 2000, which will be described later. However, it is not limited to this, and the heating unit 1200 may be connected to a separate reducing gas storage unit that stores a gas containing carbon dioxide (CO ₂ ), that is, a reducing gas. That is, the reduced iron manufacturing apparatus 1000 includes a reduction gas storage unit (not shown) in which reduction gas is stored, and the reduction gas storage unit may be provided to supply the reduction gas to the heating unit 1200. Accordingly, the heating unit 1200 may heat the reducing gas supplied from at least one of the compacted material manufacturing apparatus 2000 and the reducing gas storage unit.

The reducing gas heated in the heating unit 1200 is supplied to the reducing unit 1100 through the reducing gas supply unit 1210. That is, the reducing gas heated in the heating unit 1200 is supplied to the first reduction furnace 1100a through the reducing gas supply unit 1210. And the reduction gas supplied to the first reduction reactor (1100a) is sequentially transferred to the second reduction reactor (1100b), the third reduction reactor (1100c), and the fourth reduction reactor (1100d). And, the reduction gas used in the reduction reaction in the fourth reduction reactor (1100d) is discharged through the exhaust unit (1110). And the gas discharged from the fourth reduction reactor 1100d, that is, the exhaust gas, moves along the exhaust unit 1110 and sequentially passes through the heat exchange unit 1300 and the vibration removal unit 1400.

First, the vibration suppression unit 1400 will be described. The vibration control unit 1400 may be a means including a scrubber capable of spraying liquid, such as water, into the introduced exhaust gas. Here, the liquid or water may have a lower temperature than the exhaust gas. When water is sprayed into the exhaust gas using the vibration damping unit 1400, water vapor (H ₂ O) contained in the exhaust gas may be cooled to a temperature below the dew point and condensed. Accordingly, water (H ₂ O) can be removed from the exhaust gas. Additionally, when water is sprayed into the exhaust gas passing through the exhaust unit 1110 using the vibration control unit 1400, fine particles or dust contained in the exhaust gas may be collected in the vibration control unit. And in this way, the vibration control unit 1400 sprays a liquid, for example, water (H ₂ O), which has a lower temperature than the exhaust gas, into the exhaust gas. Accordingly, the temperature of the exhaust gas passing through the vibration control unit 1400 may decrease.

Some of the low-temperature exhaust gas from which dust has been removed in the vibration removal unit 1400 is discharged to the outside through the discharge unit 1410, and the remainder is supplied to the heat exchange unit 1300 through the first circulation unit 1420a. At this time, of the total volume of exhaust gas supplied to the vibration control unit 1400, 20 vol% to 30 vol% of exhaust gas is discharged to the outside, and 70 vol% to 80 vol% of exhaust gas is heat exchanged through the first circulation unit 1420a. It is desirable to re-supply to unit 1300.

The heat exchange unit 1300 receives low-temperature exhaust gas from which dust has been removed from the vibration removal unit 1400, and heats the low-temperature exhaust gas by exchanging heat with other high-temperature gas. That is, the heat exchange unit 1300 heats the low-temperature exhaust gas from which dust has been removed by heat-exchanging the high-temperature exhaust gas discharged from the reduction unit 1100 to heat the low-temperature exhaust gas. For example, the heat exchange unit 1300 is installed to surround the first flow path and the first flow passage through which the high-temperature exhaust gas discharged from the reduction unit 1100 passes, and the low-temperature exhaust gas discharged from the vibration removal unit 1400 is installed. It may include a second passageway that can pass through. Additionally, the first flow path may be installed to connect the exhaust unit 1110 and the exhaust gas transfer unit 1310. Accordingly, the exhaust gas discharged from the reduction unit 1100 to the exhaust unit 1110 is supplied to the first passage of the heat exchange unit 1300, and the exhaust gas used for heat exchange passes through the exhaust gas transfer unit 1310 in communication with the first passage. It may be supplied to the vibration control unit 1400. And the second flow path may be installed to connect the first circulation section 1420a and the second circulation section 1420b. Accordingly, the low-temperature exhaust gas discharged from the vibration control unit 1400 is supplied to the second flow path of the heat exchange unit 1300 through the first circulation unit 1420a. The low-temperature exhaust gas supplied to the second flow path exchanges heat with the high-temperature exhaust gas passing through the first flow path. As a result, the low-temperature exhaust gas is heated, and the heated exhaust gas passes through the second circulation part 1420b to the heating unit 1200. is supplied as

The separation unit 1500 separates carbon dioxide (CO ₂ ) from the exhaust gas from which dust has been removed. The separation unit 1500 may be installed in the first circulation unit 14720a to be located between the heat exchange unit 1300 and the vibration isolation unit 1400. Accordingly, the dust is removed from the vibration removal unit 1400 and the exhaust gas flowing into the first circulation unit 14720a passes through the separation unit 1500 and carbon dioxide (CO ₂ ) is separated. Then, the exhaust gas from which carbon dioxide (CO ₂ ) is separated flows into the heat exchange unit 1300 and exchanges heat.

This separation unit 1500 may be a means of extracting or separating carbon dioxide (CO ₂ ) from exhaust gas, for example, by using a pressure swing absorption (PSA) method. That is, the pressure swing adsorption method extracts or separates gas using the adsorption selectivity of each component with respect to the adsorbent, and the separation unit 1500 extracts or separates carbon dioxide (CO ₂ ) from the exhaust gas _. A material that can adsorb can be used as an adsorbent. At this time, carbon dioxide (CO ₂ ) adsorbed on the adsorbent can be extracted or separated, and the separation unit 1500 extracts carbon dioxide (CO ₂ ) from the exhaust gas by repeatedly adsorbing and desorbing carbon dioxide (CO ₂ ). Or it can be separated.

The melting device 3000 melts the iron source to produce molten iron, that is, molten iron. Here, the melting device 3000 may be, for example, a blast furnace. The iron source may be iron ore that has not gone through a separate reduction process. More specifically, the iron source input into the melting device 3000 may be sintered ore manufactured by sintering iron ore. Additionally, coke is introduced into the melting device 3000 together with the iron source. Here, coke is a heat source and reducing agent that melts and reduces the iron source. In other words, coke is a material containing carbon (C) (i.e., carbon material), and coke introduced into the melting device is burned by high-temperature gas to generate heat, and carbon monoxide (CO) is generated at this time. And the iron ore is melted and reduced by the heat generated by the combustion of coke and carbon monoxide (CO). Therefore, coke can be explained as being a carbon material containing carbon (C) and a heat source and reducing agent that melts and reduces iron ore. Such coke may be manufactured by heat treating coal in a coke manufacturing apparatus 5000. And the coal used as a raw material for coke may be bituminous coal, for example.

Hereinafter, a method of manufacturing molten iron in the melting device 3000 will be briefly described. High-temperature gas is blown into the melting device 3000, that is, into the lower part of the blast furnace, and iron source and coke are introduced into the upper part of the blast furnace. Here, the iron source may include iron ore or sintered ore manufactured by sintering iron ore. And coke is a material used as a heat source and reducing agent. When high-temperature gas is blown into the blast furnace, coke is burned by the high-temperature gas. Then, iron ore is reduced and melted by the heat generated by the combustion of coke and carbon monoxide (CO) to produce molten iron, or molten iron.

However, when the iron source, that is, iron ore, is reduced and melted, a large amount of carbon dioxide (CO ₂ ), an environmental pollutant, is generated. In order to reduce the generation of carbon dioxide (CO ₂ ) by iron ore, a method of agglomerating reduced iron produced by reducing iron ore using by-product gas generated during the steelmaking process and using the agglomerated reduced iron as a substitute for the iron source is used. there is. However, reduced iron has low reactivity because it has already been reduced. Therefore, when using reduced iron with low reactivity as a substitute for iron ore, the input amount of coke used as a heat source and reducing agent must be increased. However, as the input amount of coke increases, there is a problem that the amount of carbon dioxide (CO ₂ ) generated due to combustion of coke increases.

Therefore, in an embodiment of the present invention, a compacted material that can be used as an iron source, has high reactivity and suppresses the generation of carbon dioxide (CO ₂ ) during reaction is prepared, and is used as an iron source. In other words, the compacted material according to the embodiment is used as a substitute for iron ore, which is an iron source. In more detail, a compacted material containing iron carbide (Fe ₃ C) (i.e., a compacted material containing iron carbide (Fe ₃ C)) is manufactured using the compacted material manufacturing apparatus 2000, and the produced iron carbide (Fe ₃ C) is manufactured. )-containing compacted material is used as a substitute for iron source or iron ore inputted into the melting device (3000).

Hereinafter, a compacted body manufacturing apparatus 2000 for producing a compacted body containing iron carbide will be described with reference to FIGS. 1 and 2.

The compacted material manufacturing device (2000) uses raw materials containing reduced iron and biomass produced in the reduced iron manufacturing device (1000) to produce compacted material containing iron carbide (Fe ₃ C), that is, iron carbide (Fe ₃ C). Produce containing compacted material. This compacted material manufacturing apparatus 2000 includes a compacted material manufacturing unit 2100 that produces a compacted material using raw materials containing biomass and reduced iron, and a compacted material manufactured in the compacted material manufacturing unit 2100 containing hydrocarbons. It may include a reaction unit 2200 that produces a compacted material containing iron carbide by reacting with a reaction gas.

In addition, the compacted material manufacturing device 2000 is a device that connects the compacted material manufacturing device 2000 and the reaction section 2200 so that the compacted material manufactured in the compacted material production section 2100 can be supplied to the reaction section 2200. 1Transfer unit 2300, a second transfer unit connecting the reaction unit 2200 and the compacted substance supply device 4000 so that the compacted material containing iron carbide produced in the reaction unit 2200 can be supplied to the compacted substance supply device 4000 ( 2400).

Additionally, the compacted material manufacturing apparatus 2000 may include a reducing gas supply unit 2500 that supplies the gas generated when manufacturing the iron carbide-containing compacted material in the reaction unit 2200 to the heating unit 1200.

Here, each of the first and second transfer units 2300 and 2400 and the reducing gas supply unit 2500 may include a pipe having a passage and flow path through which the compacted material and the iron carbide-containing compacted material can pass.

Hereinafter, for convenience of explanation, the compacted body manufactured in the compacted body production unit 2100 and manufactured using raw materials including reduced iron and biomass will be referred to as the first compacted body. In addition, it is a compacted material produced in the reaction unit 2200, and the compacted material produced by reacting the first compacted material with a reaction gas containing hydrocarbon is called the second compacted material.

First, biomass is explained.

Biomass raw materials refer to biological organisms such as plants that synthesize organic substances by receiving solar energy, animals and microorganisms that use plants as food, and are eco-friendly energy resources that can be converted into energy.

Biomass contains carbon (C) just like coal or fossil fuels. And, carbon-based materials emit or emit carbon dioxide (CO ₂ ) into the atmosphere. The difference between coal fuel and biomass lies in the time at which carbon dioxide (CO ₂ ) is released. The process of converting carbon dioxide (CO ₂ ) in the atmosphere into coal fuel (or fossil fuel) takes millions of years. Accordingly, carbon dioxide (CO ₂ ) released into the atmosphere when coal fuel is burned is regarded as new carbon dioxide (CO ₂ ) additionally supplied to the atmosphere.

However, carbon dioxide (CO ₂ ) emitted when biomass is burned is carbon dioxide (CO ₂ ) that plants, which were the raw material for biomass, absorbed from the atmosphere for photosynthesis. In other words, when biomass is burned, carbon dioxide (CO ₂ ) absorbed from the atmosphere by plants, which were the raw material of the biomass, is emitted. Accordingly, carbon dioxide (CO ₂ ) emitted from biomass is generally not considered an environmental pollutant. And since the carbon dioxide (CO ₂ ) emitted from the combustion of biomass is carbon dioxide (CO ₂ ) absorbed from the atmosphere by plants for photosynthesis, burning biomass maintains a balance between the absorption and emission of carbon dioxide (CO ₂ ). It can be described as a process that takes place. Accordingly, biomass is defined as a carbon dioxide (CO ₂ ) neutral fuel.

Biomass is composed of polymers containing hydrocarbons. More specifically, biomass may include cellulose, hemicellulose, and lignin. Here, cellulose is a long, linear polysaccharide that is a major component of plant cell walls and is a carbon (C)-hydrogen (H) bond. Hemicellulose may be a flexible polysaccharide, excluding pectin, among the components that make up the cell wall, and is a combination of oxygen (O) and hydrogen (H). Lignin is a type of phenolic polymer that generally constitutes the woody part of trees and is a carbon (C)-carbon (C) bond.

In an embodiment, a compacted material containing iron carbide, that is, a second compacted material, is manufactured using raw materials containing biomass containing cellulose, hemicellulose, and lignin. More specifically, a second compacted material containing iron carbide is manufactured using a raw material containing at least one of lignocellulosic biomass and herbaceous biomass.

The lignin content of lignocellulosic biomass and herbaceous biomass is different. In other words, the content of lignin contained in lignocellulosic biomass is higher than that of herbaceous biomass. Here, the content of lignin contained in the lignocellulosic biomass may be 20% to 30% by weight, and the content of lignin contained in the herbaceous biomass may be less than 20% by weight.

In manufacturing the secondary compacted material containing iron carbide, when using raw materials containing lignocellulosic biomass, the lignocellulosic biomass is chips, charcoal, briquettes, etc. manufactured using wood. It may be at least one of pellets. As another example, when manufacturing the second compacted material and using herbaceous biomass as a raw material, the herbaceous biomass may be, for example, at least one of rice straw and rice husk.

Hereinafter, each configuration of the compacted material manufacturing unit 2100 will be described. At this time, for convenience of explanation, raw materials containing biomass are simply referred to as 'biomass raw materials'. And biomass raw materials may be named ‘biomass’.

The compacted material manufacturing unit 2100 includes a torrefaction device 2110 for torrefaction of biomass raw materials, a biomass storage device 2121 for storing the torrefied biomass, and reduced iron supplied from the reduced iron production device 1000. It includes a molding machine 2130 that mixes the carbonized biomass and molds the mixture to produce the first compacted material.

In addition, the compacted material manufacturing unit 2100 may further include a reduced iron storage device 2122 that stores reduced iron supplied from the reduced iron manufacturing apparatus 1000 and a crusher 2140 that crushes the produced first compacted material.

In addition, in manufacturing the first compacted material, by-products containing carbon (C) generated in at least one of the coke manufacturing device 5000, coke dry quenching (CDQ), and melting device 3000 (hereinafter referred to as , carbon-containing by-products) can be further mixed to produce it. Accordingly, the compacted material manufacturing unit 2100 may further include a carbon-containing by-product storage device 2123 for storing carbon-containing by-products generated in at least one of the coke manufacturing device 5000, the coke dry quenching device, and the melting device 3000. there is.

Biomass contains volatile matter, fixed carbon, ash, and moisture. The moisture and volatile matter contents are high, and the fixed carbon content is low compared to this. In order to use biomass as fuel, the calorific value (kcal/kg) is important. The lower the volatile matter content and the higher the fixed carbon content, the higher the calorific value (kcal/kg). Therefore, it is not desirable to use biomass with a high volatile content and low fixed carbon content as is. Therefore, the biomass is torrefied using the torrefaction device 2110 to increase the fixed carbon content. Then, the first compacted material is manufactured using biomass with an increased fixed carbon content.

The torrefaction unit 2110 is a means for carbonizing or torrefying raw materials containing biomass, that is, biomass raw materials by heating or heat treating them. For example, the torrefaction device 2110 may be a device that includes a furnace with a heating space therein. To be more specific, the torrefaction unit 2110 is installed in at least one of the main body having a heating space, the heating space of the main body, or the outside of the main body, and supplies power to the heating member and the heating member that can be heated by the supplied power. It may include a power supply that applies. Accordingly, when power is applied to the heating member using a power supply, the heating member is resistively heated and heat is generated. As a result, the heating space of the main body is heated and the temperature rises, which causes the biomass raw material charged into the heating space to be heated. While heating the biomass raw material in the heating space of the main body in this way, the heating space of the main body is maintained in an oxygen-free (anaerobic) or oxygen-depleted state. For this purpose, an inert gas can be supplied to the heating space of the main body, and the biomass raw material can be heated while the heating space is maintained in an inert gas atmosphere.

The process of heating biomass raw materials using the torrefaction device 2110 as described above to thermally decompose the biomass raw materials to remove volatile components and increase the content of fixed carbon is called a torrefaction process. At this time, the torrefaction unit 2110 heats the biomass raw material to a temperature at which it can be thermally decomposed. In other words, the torrefaction unit 2110 heats the biomass raw material to a temperature at which it can be torrefaction. This can be achieved by adjusting the amount of power supplied to the heating member using a power supply.

When the biomass raw material is heated and pyrolyzed using the torrefaction device 2110, hemicellulose, which is a combination of oxygen (O) and hydrogen (H) contained in the biomass raw material, is decomposed, and volatile matter, that is, carbon dioxide (CO ₂ ) , carbon monoxide (CO), methane (CH ₄ ), and hydrogen (H ₂ ) are removed by evaporation into a gaseous state. As a result, the content of volatile matter in biomass raw materials decreases. In addition, when the biomass raw material is heated and pyrolyzed using the torrefaction device 2110, cellulose, which is a carbon (C)-hydrogen (H) complex, and carbon (C)-carbon (C) complex contained in the biomass raw material. The phosphorus lignin component remains and the fixed carbon content increases.

In order to thermally decompose or torrefy biomass raw materials, the temperature at which the torrefaction unit 2110 heats the biomass raw materials may be 200°C to 500°C. More preferably, the torrefaction unit 2110 can torrefy biomass raw materials by heating them to a temperature of 250°C to 350°C. The temperature and heating time for pyrolyzing or torrefaction of biomass raw materials can be adjusted differently depending on the biomass raw materials used.

For example, when using a raw material containing lignocellulosic biomass, the torrefaction unit 2110 heats the biomass raw material to 250°C to 500°C, preferably 250°C to 350°C, and heats the biomass raw material to 250°C to 350°C for 60 minutes at this temperature. It is preferable to heat for 90 minutes. As another example, when using raw materials containing herbaceous biomass, the torrefaction device 2110 heats the biomass raw materials to a temperature of 200 ℃ or more and less than 300 ℃, preferably 200 ℃ or more and less than 250 ℃, It is preferable to heat at temperature for 30 to 40 minutes. In this way, compared to the case of using raw materials containing herbaceous biomass, when using raw materials containing lignocellulosic biomass, the heating temperature is increased and the heating time is prolonged. This is because the content of lignin contained in is high. That is, the content of lignin, a carbon (C)-carbon (C) complex, contained in lignocellulosic biomass is relatively high compared to herbaceous biomass, and relatively high temperature and time are required to decompose the lignin.

Table 1 is a table showing the contents and calorific value of volatile matter, fixed carbon, ash, and moisture contained in biomass raw materials before and after torrefaction treatment.

For the experiment, samples, which were biomass raw materials, were prepared. At this time, lignocellulosic biomass raw materials were used. Then, the contents (% by weight) of volatile matter, fixed carbon, ash, and moisture contained in the sample were detected, and the calorific value (kcal/kg) was measured.

In addition, the sample was torrefaction treated by heating it to a temperature of 350°C for 60 minutes using the torrefaction machine 2110 according to the example. Afterwards, the contents (% by weight) of volatile matter, fixed carbon, ash, and moisture contained in the torrefaction treated sample were detected, and the calorific value (kcal/kg) was measured.

Sample before torrefaction treatment Sample after torrefaction treatment Volatile matter content (% by weight) 81.52 34.27 Content of fixed carbon (% by weight) 11.63 61.55 Ash content (% by weight) 1.54 1.31 Moisture content (% by weight) 5.31 2.87 Calorific value (kcal/kg) 4701.44 7000.24

Referring to Table 1, compared to the sample before the torrefaction treatment, the content of volatile matter and moisture contained in the sample after the torrefaction treatment is low, and the content of fixed carbon is high. From this, it can be seen that by heating or torrefaction of biomass raw materials, the content of volatile matter and moisture can be reduced, and the content of fixed carbon can be increased.

In addition, the calorific value of the sample after the torrefaction treatment is higher than the calorific value of the sample before the torrefaction treatment. From this, it can be seen that the calorific value can be increased by torrefying the biomass raw material to reduce the content of volatile matter and moisture and increase the content of fixed carbon.

The biomass storage device 2121 receives and stores the torrefaction-processed biomass material from the torrefaction machine 2110, and supplies the stored biomass material to the molding machine 2130. The biomass storage device 2121 may be provided in any shape as long as it can accommodate biomass raw materials.

The reduced iron storage device 2122 receives reduced iron from the reduced iron manufacturing device 1000, stores it, and supplies the stored reduced iron to the molding machine 2130. More specifically, the reduced iron storage 2122 is connected to the fourth reduction furnace 1100d of the reduction unit 1100, and can receive and store reduced iron from the fourth reduction furnace 1100d. The reduced iron storage unit 2122 may be provided in any shape as long as it can accommodate reduced iron.

The molding machine 2130 mixes the torrefied biomass raw material supplied from the biomass storage 2121 and the reduced iron supplied from the reduced iron storage 2122, and molds this mixture to produce a first compacted body of a predetermined size. do. At this time, the molding machine 2130 may be a device that compresses and molds a mixture of torrefied biomass raw materials and reduced iron while heating. For example, the molding machine 2130 may include a hopper into which biomass raw materials and reduced iron are input, and a pair of rolls located below the hopper and facing each other. And each of the pair of rolls can rotate, and may be a roll with teeth formed on its outer circumferential surface.

A method of manufacturing the first compacted body using this molding machine 2130 will be briefly described below. First, biomass raw materials and reduced iron are input into the hopper. Accordingly, biomass raw materials and reduced iron are mixed inside the hopper. Then, the mixture of biomass raw materials and reduced iron is charged between a pair of rolls, and as the mixture is pressed and molded between the pair of rolls, a first compacted body having a predetermined shape is produced. At this time, a heater may be installed on a pair of rolls, and the mixture may be charged and compressed while being heated between the pair of rolls heated by the heater. As another example, a means for heating the biomass raw material and reduced iron may be installed inside the hopper, and the heated mixture may be charged between a pair of rolls. Therefore, a mixture of biomass raw materials and reduced iron can be compressed by a pair of rolls in a heated state, thereby producing the first compacted material.

In the above, it was explained that torrefied biomass raw material and reduced iron are added and mixed into the molding machine 2130, and this mixture is molded. However, it is not limited to this, and a separate mixer for mixing torrefied biomass and reduced iron may be provided. Then, the mixture mixed in the mixer can be transferred to the molding machine 2130 and molded.

In addition, in the above, it was explained that the molding machine 2130 produces a compacted body using a compression method. However, it is not limited to this, and the molding machine 2130 may be any means that can produce a compacted body using a mixture.

When the mixture of torrefied biomass raw material and reduced iron is hot-molded in the molding machine 2130, the first compacted body containing the torrefied biomass raw material and reduced iron is manufactured. At this time, the torrefied biomass raw material and reduced iron may be physically combined or contacted by molding using the molding machine 2130. In other words, the first compacted body is produced by physically combining or contacting the torrefied biomass raw material and reduced iron.

In addition, the torrefied biomass raw material is one in which the content of fixed carbon is increased by torrefied biomass as described above. Accordingly, the torrefied biomass raw material included in the first compacted body can be defined as a material that provides carbon (C) to the first compacted body, that is, carbon material or a carbon source. Therefore, the first compacted body manufactured in the molding machine 2130 can be described as a compacted body containing carbon (C).

And, since the first compacted material contains reduced iron, it can be used as an iron source input into the melting device. In other words, it can be used as a substitute for iron ore input into the melting device. In addition, as described above, the first compacted material includes biomass raw materials containing carbon (C) in addition to reduced iron. Accordingly, the first compacted material according to the example has higher reactivity than the compacted material manufactured using only reduced iron.

The crusher 2140 crushes the first compacted material manufactured in the molding machine 2130. At this time, the crusher 2140 is not particularly limited as long as it is a means capable of crushing the first compacted material, and any means may be used.

In manufacturing the first compacted material, a carbon-containing by-product containing carbon (C), which is a by-product generated during the steelmaking process, can be used. That is, the first compacted body can be produced by further mixing carbon-containing by-products in addition to the torrefied biomass raw material and reduced iron. In other words, as a raw material mixed to improve the reactivity of the compacted material, carbon-containing by-products generated during the steelmaking process can be additionally mixed in addition to biomass raw materials. To this end, the compacted material manufacturing unit 2100 may further include a carbon-containing by-product storage device 2123 that stores carbon-containing by-products generated during the steelmaking process.

Here, by-products generated during the steelmaking process include by-products generated during the coke manufacturing process in the coke manufacturing device 5000, by-products generated in the coke dry quenching device for cooling coke, and by-products generated during molten iron manufacturing in the melting device 3000. It may include at least one of:

The carbon-containing by-product storage device 2123 stores carbon-containing by-products generated in at least one of the coke manufacturing device 5000, the coke dry quenching device, and the melting device 3000. The carbon-containing by-product storage device 2123 may be provided in any shape as long as it can accommodate the carbon-containing by-products.

By-products generated in the coke manufacturing apparatus 5000 may be by-products generated in the process of producing coke by heat treating coal. To be more specific, in the coke production apparatus 5000, bituminous coal, which is raw material coal, is charged into a coke oven and heated to remove moisture and ash, and is manufactured by agglomerating. At this time, coke that has not been lumped cannot be input into the melting device 3000, and in the example, it is defined as a by-product. Accordingly, the by-product generated from the coke manufacturing apparatus 5000 may be coke that has not been lumped. And by-products generated from the coke manufacturing device 5000 may include carbon (C), ash, hydrogen (H), and nitrogen (N). At this time, carbon (C) may be 85% by weight or more (less than 100% by weight) in the entire by-product generated from the coke production device 5000, and the balance may be ash, hydrogen (H), and nitrogen (N). You can. Additionally, ash may include at least one of Al ₂ O ₃ , SiO ₂ , CaO, MgO, P ₂ O ₅ , TiO ₂ , Na ₂ O, K ₂ O, and ZnO.

The coke dry extinguishing device is a device that extinguishes and cools agglomerated coke in a dry method. In addition, by-products generated from the coke dry extinguishing device may be fine particles that are worn away when dry-drying the agglomerated coke. The by-products generated from the coke dry extinguishing device may be the same as the components generated from the coke manufacturing device 5000. In other words, the by-products generated from the coke dry extinguishing device contain more than 85% by weight (less than 100% by weight) of carbon (C), and the balance may include ash (Ash), hydrogen (H), and nitrogen (N). there is. And, ash may include at least one of Al ₂ O ₃ , SiO ₂ , CaO, MgO, P ₂ O ₅ , TiO ₂ , Na ₂ O, K ₂ O, and ZnO.

The by-product generated in the melting device 3000 may be dust collected from exhaust gas discharged to the outside of the melting device 3000 when molten iron is manufactured in the melting device 3000. And the melting device 3000 may be, for example, a blast furnace. Accordingly, the by-product generated in the melting device 3000 is dust collected from exhaust gas generated when manufacturing molten iron in a blast furnace. By-products generated in the melting device 3000 may include M. Fe, FeO, SiO ₂ , Al ₂ O ₃ , CaO, MgO, K ₂ O, Na ₂ O, Zn, S, and C. Here 'M. 'Fe' may mean 'Metal Fe'. In addition, C (carbon) contained in the by-product generated in the melting device 3000 may be 10% by weight to 17% by weight, and the content of T.Fe may be 45% by weight to 58% by weight. Here, 'T.Fe content' refers to the total content of Fe (iron) contained in the by-product, which is the content of iron (Fe) contained in iron oxide such as FeO and the content of M. Fe (metallic iron). It means the combined content.

When such a carbon-containing by-product is input into the molding machine 2130, the molding machine 2130 mixes the torrefied biomass raw material, reduced iron, and the carbon-containing by-product and hot-forms this mixture to produce the first compacted body. Accordingly, the first compacted material includes torrefied biomass raw materials, reduced iron, and carbon-containing by-products. Here, the carbon-containing by-product of the coke production device 5000 or the carbon-containing by-product of the coke quenching device used as a carbon-containing by-product contains 85% by weight or more of carbon, and the carbon-containing by-product of the melting device 3000 contains 10% carbon (C). It is contained in weight% to 17% by weight. Accordingly, the carbon-containing by-product included in the first compacted material can be defined as a material that provides carbon (C) together with torrefied biomass or a material that improves reactivity.

The reaction unit 2200 reacts the first compacted substance produced in the compacted substance production unit 2100 with a gas containing hydrocarbons (hereinafter referred to as reaction gas) to generate iron carbide (Fe ₃ C) in the first compacted substance. Let's do it. That is, at least one of metallic iron (Metal Fe) and iron oxide (FeO, Fe ₂ O ₃ , etc.) contained in the first compacted material is converted into iron carbide (Fe ₃ C). Here, the reaction gas containing hydrocarbons may be a reaction gas containing at least one of CH ₄ and C ₂ H ₂ hydrocarbons. Additionally, the reaction gas may be a gas that further contains hydrogen in addition to hydrocarbons.

For example, the reaction unit 2200 may be a device including a furnace provided with a reaction space where the first compacted material and the reaction gas can react. To be more specific, the reaction unit 2200 is installed in at least one of the main body having a reaction space, the reaction space of the main body, or the outside of the main body, and applies power to the heating member and the heating member that can be heated by the supplied power. It may include a power supply. Accordingly, when power is applied to the heating member using a power supply, the heating member is resistively heated and heat is generated. As a result, the reaction space of the main body is heated and the temperature rises, and as a result, the first compacted material and the reaction gas charged into the reaction space are heated and can react. At this time, for a smooth or efficient reaction between the first compacted material and the reaction gas, the temperature of the reaction space is preferably adjusted to 700°C to 800°C.

Hereinafter, the reaction between the first compacted material and the reaction gas that occurs in the reaction unit 2200 will be described. When the first compacted material and the reaction gas are introduced into the reaction space of the reaction unit 2200 heated to a predetermined temperature, at least one of iron (Fe) and iron oxide (FeO, Fe ₂ O ₃ , etc.) contained in the first compacted material and the hydrocarbons contained in the reaction gas react. This reaction may be, for example, Scheme 1 and Scheme 2, and iron carbide (Fe ₃ C) is produced by this reaction. That is, iron (Fe) contained in at least one of metallic iron (Metal) and iron oxide (FeO, Fe ₂ O ₃ , etc.) contained in the first compacted material reacts with hydrocarbons contained in the reaction gas, and thus metallic iron (Metal) and iron oxides (FeO, Fe ₂ O ₃ , etc.) are converted to iron carbide (Fe ₃ C). In other words, the second compacted body, which is a compacted body containing iron carbide (Fe ₃ C), is produced.

Scheme 1) 3Fe + CH ₄ --> Fe ₃ C + 2H ₂

Scheme 2) 3FeO + CH ₄ --> Fe ₃ C + 3H ₂ O

Scheme 3) CH ₄ + H ₂ O --> CO + 3H ₂ O

Scheme 4) C + H ₂ O --> CO + H ₂ O

Additionally, the reaction gas containing hydrocarbons can be reformed into a gas containing carbon monoxide (CO) and hydrogen (H) using the first compacted material as a catalyst (see Scheme 3 and Scheme 4). Here, the gas containing carbon monoxide (CO) and hydrogen (H) can be supplied to the reduction unit 1100 and used as a reducing gas to reduce iron ore. Accordingly, reforming the reaction gas into a gas containing carbon monoxide (CO) and hydrogen (H) can be explained as reforming the reaction gas into a reduction gas containing carbon monoxide (CO) and hydrogen (H). That is, in the reaction unit 2200, the first compacted material is reacted with the reaction gas to produce the second compacted material containing iron carbide (Fe ₃ C), and the reaction gas is reacted with the reaction gas to contain carbon monoxide (CO) and hydrogen (H). Reformed with gas. At this time, the ratio of the combined volume of carbon monoxide (CO) and the volume of hydrogen (H) in the reformed reducing gas may be 85 vol% (volume %) or more.

Here, the reaction of reforming the reaction gas into a reducing gas containing carbon monoxide (CO) and hydrogen (H) (Reaction Scheme 3 and Scheme 4) is a reaction in which the volume of the reaction space of the main body increases. Accordingly, the lower the pressure in the reaction space of the main body is adjusted to a pressure below normal pressure, the more the reaction rate between the first compacted material and the reaction gas can be improved.

The second compacted material produced in the reaction unit 2200 is introduced into the melting device 3000 through the second transfer unit 2400 and the compacted material supply device 4000. And the reducing gas produced by reforming the reaction gas in the reaction unit 2200, that is, the reformed reduction gas, is supplied to the heating unit 1200 of the reduced iron manufacturing apparatus 1000 through the reducing gas supply unit 2500. The reformed reduction gas supplied to the heating unit 1200 is supplied to the reduction unit 1100 and used to reduce iron ore. In this way, by-product gas generated in the reaction unit 2200, that is, reformed reduction gas, is supplied to the reduction unit 1100 to reduce iron ore, thereby suppressing or preventing the generation of additional carbon dioxide (CO ₂ ). In other words, when producing reduced iron by reducing iron ore using carbon materials such as coke, there is a problem of additional carbon dioxide (CO ₂ ) being generated, but as in the embodiment, the by-product gas (reformed reduction gas) generated in the reaction unit 2200 ), if it is used to reduce iron ore rather than being disposed of, the generation of additional carbon dioxide (CO ₂ ) can be suppressed or prevented.

In mixing reduced iron and torrefied biomass raw materials and molding this mixture to produce a first compacted body, the mixture is mixed so that the content of fixed carbon in the entire first compacted body is 2% by weight to 5% by weight. For this purpose, when mixing reduced iron and torrefied biomass raw material, the torrefied biomass raw material in the entire mixture is more than 0% by weight and less than 10% by weight, and the reduced iron is mixed so that it is more than 90% by weight and less than 100% by weight. do. More preferably, the mixture is mixed so that the torrefied biomass raw material is more than 5% by weight and less than 8% by weight, and the reduced iron is more than 88% by weight and less than 95% by weight of the entire mixture.

On the other hand, when the torrefied biomass raw material in the entire mixture exceeds 10% by weight, the strength of the first and second compacted bodies produced may be weak. If the strength of the first compacted material is weak, the first compacted material may be damaged and lost while being transported to the reaction unit. Additionally, if the strength of the first compacted material is weak, the strength of the second compacted material produced by reacting the first compacted material with a hydrocarbon may be weak. And, if the strength of the second compacted material is weak, it may be damaged when input into the melting device 3000 and dust may be generated. The generated dust may impede the flow of gas by worsening the ventilation inside the melting device 3000, which may cause a problem in which molten iron cannot be easily manufactured.

Therefore, the torrefied biomass raw material in the entire mixture is mixed so that it exceeds 0% by weight and does not exceed 10% by weight.

Meanwhile, when reduced iron obtained by reducing iron ore in the reduced iron production device is introduced into the melting device 3000, the reactivity of the reduced iron is low. That is, when a compacted body manufactured by agglomerating reduced iron produced by reducing iron ore is input into the melting device 3000, the reactivity of the compacted body is low. This is because the compacted material is manufactured using reduced iron that has already been reduced and produced in the reduced iron manufacturing apparatus 1000.

However, in an embodiment of the present invention, in producing a compacted material by compacting reduced iron, a raw material containing carbon (C) is additionally added. In other words, a raw material containing carbon (C) is added to reduced iron to produce a compacted material with an increased carbon (C) content. The compacted body produced by mixing raw materials containing carbon (C) and reduced iron in this way has a higher carbon (C) content than the compacted body manufactured by compacting only reduced iron. Therefore, if a compacted material is manufactured by adding a raw material containing carbon (C) to reduced iron, the reactivity of the compacted material can be improved. Therefore, compared to when a compacted material manufactured using only reduced iron is input as an iron source, when a compacted material manufactured by additionally adding carbon (C) to reduced iron is input as an iron source, the amount of coke input can be reduced.

And, as a raw material containing carbon (C), a raw material containing biomass (biomass raw material) is used. When the biomass raw material contained in the compacted material is burned, carbon monoxide (CO) is generated, and the carbon monoxide (CO) and iron ore react to generate carbon dioxide (CO ₂ ). However, as described above, carbon dioxide (CO ₂ ) generated by biomass raw materials is considered carbon dioxide (CO ₂ ) that plants, which were raw materials for biomass, absorbed from the atmosphere for photosynthesis. In other words, when biomass raw materials are burned, carbon dioxide (CO ₂ ) absorbed from the atmosphere by plants that were the raw materials for the biomass raw materials is emitted. Accordingly, carbon dioxide (CO ₂ ) emitted from biomass is not considered an environmental pollutant. Therefore, when compacted materials containing biomass raw materials are used as a substitute for the iron source or iron ore introduced into the melting device 3000, worsening of atmospheric pollution due to carbon dioxide (CO ₂ ) can be suppressed or prevented. .

In addition, after torrefaction of the biomass raw material, the torrefied biomass raw material is mixed with reduced iron to produce a compacted material. When biomass feedstock is torrefied, the fixed carbon content increases. Accordingly, the content of fixed carbon contained in the compacted material can be increased. Here, to explain in other words that the content of fixed carbon contained in the compacted material increases, it can be explained that the degree of carbonization of the compacted material increases. And if the degree of carbonization or the content of fixed carbon in the compacted material increases, the reactivity can be further improved. That is, the reactivity of the compacted body containing torrefied biomass is higher than that of the compacted body containing non-torrefied biomass raw materials.

Then, rather than directly inputting the compacted material containing carbon (C) into the melting device 3000, the compacted material is reacted with a reaction gas containing hydrocarbon to produce a compacted material containing iron carbide (Fe ₃ C). That is, metal iron (Metal Fe) and iron oxide (FeO, Fe ₂ O ₃ , etc.) contained in the compacted material are converted into iron carbide (Fe ₃ C) by reacting with hydrocarbons. Accordingly, a compacted material containing iron carbide (Fe ₃ C) is produced. When iron carbide (Fe ₃ C) is generated in the compacted material, the melting point of the compacted material can be reduced. This is because the melting point of iron carbide (Fe ₃ C) is lower than that of metal iron (Metal Fe) and iron oxide (FeO, Fe ₂ O ₃ , etc.).

Therefore, when a compacted material containing iron carbide (Fe ₃ C) is used as the iron source input to the melting device 3000, the energy consumed to reduce and melt the compacted material can be reduced. In other words, there is no need to increase the amount of coke input to reduce and melt the compacted material, so the amount of coke consumed can be reduced. Additionally, at least one of the supply amount of high temperature gas and the temperature of air can be reduced.

Going back to FIGS. 1 and 2, the reaction gas supply device 6000 will be described.

The gas generated when producing coke in the coke production device 5000 (hereinafter referred to as by-product gas) and the gas generated when torrefying biomass raw materials in the torrefaction unit 2110 (hereinafter referred to as by-product gas) include hydrocarbons and hydrogen. may be included. And the hydrocarbons contained in the by-product gas may include at least one of CH ₄ and C ₂ H ₂ . Therefore, at least one of the by-product gas generated when producing coke in the coke manufacturing apparatus 5000 and the by-product gas generated when torrefying biomass raw materials in the torrefaction unit is used as a reaction gas supplied to the reaction unit 2200. use. For this purpose, the molten iron manufacturing facility is equipped with a reaction gas supply device 6000 that recovers by-product gas generated when producing coke in the coke manufacturing device 5000 and supplies it to the reaction unit 2200.

The reaction gas supply device 6000 includes a first gas recovery unit 6110a that recovers the by-product gas generated in the coke manufacturing device 5000, and a second gas recovery unit that recovers the by-product gas generated in the torrefaction unit 2110. A heating unit 6100 connected to the unit 6110b and the first and second gas recovery units 6110a and 6110b to heat the recovered by-product gas, and the by-product gas heated in the heating unit 6100 is connected to the reaction unit 2200. It may include a gas supply unit 6120 that supplies hydrogen sulfide, a hydrogen sulfide supply unit 6130 that supplies hydrogen sulfide to the gas supply unit 6120, and an oxygen supply unit 6140 that supplies oxygen to the gas supply unit 6120.

Here, the first and second gas recovery units 6110a and 6110b, the gas supply unit 6120, the hydrogen sulfide supply unit 6130, and the oxygen supply unit 6140 each have a pipe provided with a passage or flow path through which gas can pass. It can be included.

One end of the first gas recovery unit 6110a may be connected to the coke manufacturing device 5000 and the other end may be connected to the heating unit 6100. By-product gas generated during coke production in the coke production apparatus 5000 may be supplied to the heating unit 6100.

The second gas recovery unit 6110b may have one end connected to the torrefaction unit 2110 and the other end connected to the heating unit 6100. Accordingly, by-product gas generated when torrefaction of biomass raw materials in the torrefaction unit 2110 may be supplied to the heating unit 6100. At this time, the reaction gas supply device 6000 may be provided to include at least one of the first and second gas recovery units 6110a and 6110b. That is, the reaction gas supply device 6000 may be provided to supply at least one of the by-product gas generated in the coke manufacturing device 5000 and the by-product gas generated in the torrefaction unit 2110 to the reaction unit 2200. .

One end of the gas supply unit 6120 is connected to the heating unit 6100 and the other end is connected to the reaction unit 2200. Accordingly, the by-product gas heated in the heating unit 6100 may be supplied to the reaction unit 2200 through the gas supply unit 6120.

In producing iron carbide (Fe ₃ C) in the first compacted material by reducing the first compacted material with a reaction gas, hydrogen sulfide (H ₂ S) gas is also supplied. That is, the reaction gas and hydrogen sulfide (H ₂ S) gas are supplied to the reaction unit 2200. For this purpose, the hydrogen sulfide supply unit 6130 is connected to the gas supply unit 6120 through which the by-product gas passes. Accordingly, by-product gas and hydrogen sulfide (H ₂ S) are mixed in the gas supply unit 6120. At this time, the amount of iron carbide (Fe ₃ C) generated in the first compacted material may vary depending on the supply flow rate of the supplied hydrogen sulfide (H ₂ S) gas. Additionally, as the supply flow rate of hydrogen sulfide (H ₂ S) gas increases, the amount of iron carbide (Fe ₃ C) produced may decrease. Therefore, it is desirable to adjust the supply flow rate of hydrogen sulfide (H ₂ S) gas in order to generate a target amount of iron carbide (Fe ₃ C). At this time, it is preferable that the ratio (P _H2S / P _H2 ) of the partial pressure of hydrogen sulfide (P _H2S ) to the partial pressure of hydrogen (P _H2 ) is controlled to be 0.0003 to 0.0005.

An oxygen supply unit 6140 is connected to the gas supply unit 6120 through which the by-product gas passes. Accordingly, by-product gas, hydrogen sulfide gas, and oxygen are mixed inside the gas supply unit 6120. At this time, by adjusting the volume ratio of oxygen in the entire gas mixed with by-product gas, hydrogen sulfide gas, and oxygen, the temperature of the by-product gas can be adjusted to a temperature at which reaction is easy. That is, by adjusting the supply flow rate of oxygen supplied through the oxygen supply unit, the temperature of the gas supplied to the reaction unit 2200 can be adjusted to a temperature at which reaction with the first compacted material is easy.

The compacted material supply device 4000 includes a cooling unit 4100 for cooling the second compacted substance produced in the reaction unit 2200, a compacted substance storage unit 4200 for storing the cooled second compacted substance, and a compacted substance storage unit. It may include a cutout portion 4300 that controls the amount of the second compacted material stored in 4200 and supplies it to the melting device 3000.

In addition, the compacted substance supply device 4000 includes a first transfer unit 4110 connecting the cooling unit 4100 and the compacted substance storage unit 4200, and a first transfer unit 4110 connecting the compacted substance storage unit 4200 and the cut-out unit 4300. It may include a second transfer unit 4210 and a third transfer unit 4310 connecting the cutout part 4300 and the melting device 3000. Here, each of the first to third transfer units 4110 to 4310 may include a pipe provided with a passage or flow path through which the second compacted material can pass.

The cooling unit 4100 receives the second compacted material from the reaction unit 2200 and cools it. This cooling unit 4100 may be a means for cooling the second compacted material using, for example, a low-temperature gas. Of course, any means that can cool the second compacted material may be used as the cooling unit 4100.

The compacted material storage unit 4200 stores the cooled second compacted material. This compacted material storage unit 4200 may be provided in any shape as long as it can accommodate or store the second compacted material.

The cutting unit 4300 cuts out the second compacted material stored in the compacted material storage unit 4200 and supplies it to the third transfer unit 4310. Here, the cutout portion 4300 may be a means including, for example, a conveyor belt whose transfer speed can be adjusted. This cutout part 4300 can control the amount of the second compacted material transferred to the third transport unit 4310 by controlling the transport speed of the conveyor belt. As another example, the cutout 4300 may be a means including a rotating drum whose rotation speed can be adjusted. This cutout part 4300 can control the amount of the second compacted material transferred to the third transport part 4310 by controlling the transport speed of the rotating drum. Of course, the cutting unit 4300 is not limited to the above-described example, and various means can be applied to adjust the amount of the second compacted substance stored in the compacted substance storage unit 4200 to be transferred to the third transfer unit 4310. do.

Figure 3 shows the results of an experiment on the reduction rate of compacted materials according to comparative examples and examples.

For the experiment, the compacted body according to the comparative example and the compacted body according to the example were prepared. Here, the compacted body according to the comparative example is a compacted body manufactured by molding reduced iron. And the compacted body according to the embodiment is a compacted body manufactured by mixing reduced iron and torrefied biomass raw materials and molding them.

At this time, reduced iron, which is the material of the compacted material according to the comparative examples and examples, was used, which has the same reduction rate of 68.4%. In addition, in manufacturing the compacted material according to the example, the torrefied biomass raw material was adjusted to 5% by weight based on the total mixture of reduced iron and torrefied biomass raw material.

And component analysis was performed on each compacted material according to Comparative Examples and Examples.

Next, the compacted material according to Comparative Examples and Examples was subjected to a reduction reaction. That is, each of the compacted materials according to Comparative Examples and Examples was introduced into the upper part of the blast furnace simulation device, and gas was introduced into the lower part of the blast furnace simulation device to cause a reduction reaction of the compacted materials. At this time, gas with a composition similar to that used in an actual blast furnace was used. More specifically, the gas supplied to the lower part of the blast furnace simulation device contains 53% by weight of carbon monoxide, 11% by weight of carbon dioxide, 21% by weight of hydrogen, and 15% by weight of nitrogen. When this gas is supplied to the blast furnace simulation device, the compacted material introduced into the blast furnace simulation device is reduced. When supplying gas to the blast furnace simulation device, it was supplied so that the temperature inside the blast furnace simulation device over time was similar to the temperature of the blast furnace.

Then, the experiment was conducted until the compacted material introduced into the blast furnace simulation device did not melt but remained in a solid state, that is, in a lumpy state. That is, the time for reacting the compacted materials according to Comparative Examples and Examples inside the blast furnace simulation device was the same, and the reaction time was made the same under the condition that all compacted materials according to Comparative Examples and Examples were maintained as compacted materials.

Next, when a certain period of time has elapsed, the compacted materials according to the comparative examples and examples are taken out from the blast furnace simulation device. In addition, component analysis was conducted on the exported compacted material.

And the reduction rate was calculated for each compacted material of Comparative Examples and Examples. That is, the reduction rate is calculated using the difference between the component content of the compacted material before being introduced into the blast furnace simulation device (i.e., before the reduction reaction) and the component content of the compacted material after being introduced into the blast furnace simulation device and causing the reduction reaction. More specifically, it is calculated using the difference in the number of moles (mol) of oxygen bound to each mole (mol) of Fe in the compacted material before and after being introduced into the blast furnace simulation device. Among the components included in the compacted material, the calculation was based on the number of moles (mol) of oxygen bound per 1 mole (mol) of Fe in total Fe. To explain this more specifically, the maximum number of moles (mol) of oxygen that can be combined per 1 mole (mol) of Fe of the compacted material before the reduction reaction is the ratio (mol) of Fe of the compacted material after the reduction reaction (A). The reduction rate is calculated using the ratio of the number of moles (B) of oxygen bound to the sugar, and can be calculated using the method shown in Equation 1 below.

[Formula 1]

Referring to Figure 3, it can be seen that the reduction rate of the compacted material according to the example is higher than that of the comparative example. That is, in low temperature areas where the reaction does not actively occur, for example, below 650°C, the reduction rates of compacted materials according to Comparative Examples and Examples were similar. However, in the section where the reaction is active as the temperature increases, for example, the section exceeding 650°C, the reduction rate of the compacted material in the Example is higher than in the Comparative Example. From this, it can be seen that when producing a compacted material for use as an iron source by adding biomass raw materials to reduced iron, the reduction rate can be improved.

In addition, from the results of FIG. 3, it can be seen that the temperature required for the compacted material according to the example is lower than the temperature required for the compacted material according to the comparative example in order to reduce the compacted material at a predetermined reduction rate. Therefore, it can be seen that energy for reduction and melting of iron oxide can be saved by using the compacted material according to the example.

Figure 4 is a flowchart showing a method of manufacturing molten iron using a molten iron manufacturing facility according to an embodiment of the present invention.

Hereinafter, a method of manufacturing molten iron using a molten iron manufacturing facility according to an embodiment of the present invention will be described with reference to FIGS. 2 and 4.

First, a method for producing a second compacted material containing iron carbide (Fe ₃ C) (S100) will be described. Reduced iron is manufactured in the reduced iron manufacturing apparatus 1000 (S110). To this end, raw materials containing iron ore are input into the reduction unit 1100 and a reducing gas containing carbon monoxide (CO) is supplied to reduce the raw materials to produce reduced iron. Here, the iron ore supplied to the reduction unit 1100 may be fine iron ore, that is, powdered iron ore. In addition, the reducing gas supplied to the reduction unit 1100 may be a gas generated in the reaction unit of the compacted material manufacturing apparatus 2000, and after this gas is supplied to the heating unit 1200 and heated, the reduction unit 1100 can be supplied. The reduced iron produced in the reduction unit 1100 is transferred to and stored in the reduced iron storage unit 2122 of the compacted material production unit 2100.

While manufacturing reduced iron, biomass raw materials are prepared on the one hand (S121), and the prepared biomass raw materials are torrefaction (S122). That is, the biomass raw material is charged into the torrefaction device 2110, and the biomass material is thermally decomposed in the torrefaction device 2110 to be torrefaction. To be more specific, biomass raw materials are charged into the reaction space of the torrefaction device 2110, and the reaction space is heated to a temperature of 200°C to 500°C. Accordingly, hemicellulose, which is a combination of oxygen (O) and hydrogen (H) contained in biomass raw materials, is decomposed, and volatile components, namely carbon dioxide (CO ₂ ), carbon monoxide (CO), methane (CH ₄ ), and hydrogen (H ₂ ), are decomposed. is evaporated and removed as a gas. As a result, the content of volatile matter in biomass raw materials decreases. In addition, cellulose, a carbon (C)-hydrogen (H) bond, and lignin, a carbon (C)-carbon (C) bond, contained in biomass raw materials remain, increasing the fixed carbon content.

When the biomass raw material is torrefied in this way, the first compacted material is manufactured using reduced iron and the torrefied biomass raw material (S140). For this purpose, reduced iron and torrefied biomass raw materials are charged into the molding machine 2130, and the charged raw materials are heated and molded in the molding machine 2130 to produce the first compacted body.

In manufacturing the first compacted material, it can be manufactured by further adding carbon-containing by-products generated during steelmaking operations. That is, the first compacted body may be manufactured using carbon-containing by-products generated from at least one of the coke manufacturing apparatus 5000, the coke dry quenching apparatus, and the melting apparatus. For this purpose, carbon-containing by-products generated from at least one of the coke production device 5000, the coke dry digestion device, and the melting device 3000 are prepared (S130), and are inputted into the molding machine 2130 to produce reduced iron, biomass raw materials, A first compacted material containing carbon-containing by-products is produced.

Next, the produced first compacted material is crushed (S150), and the crushed first compacted material is introduced into the reaction unit 2200 to produce a second compacted material containing iron carbide (Fe ₃ C) (S160). That is, the first compacted material is introduced into the reaction unit 2200, and a reaction gas containing hydrocarbon and hydrogen is introduced. At this time, it is desirable to adjust the temperature inside the reaction unit 2200 to 700°C to 800°C.

And, the reaction gas supplied to the reaction unit 2200 can be used by recovering at least one of the by-product gas generated in the coke manufacturing apparatus 5000 and the by-product gas generated in the torrefaction unit 2110. That is, the by-product gas generated in at least one of the coke manufacturing device 5000 and the torrefaction device 2110 is recovered and supplied to the heating unit 6100. Accordingly, the by-product gas is heated in the heating unit 6100, and the heated by-product gas is supplied to the reaction unit 2200 through the gas supply unit 6120.

When the by-product gas passes through the gas supply unit 6120, hydrogen sulfide and oxygen are supplied to the gas supply unit 6120 using the hydrogen sulfide supply unit 6130 and the oxygen supply unit 1220. Accordingly, by-product gas containing hydrocarbons, hydrogen sulfide, and oxygen are mixed in the gas supply unit 6120, and the mixed gas is supplied to the reaction unit 2200. When supplying hydrogen sulfide to the gas supply unit 6120, the ratio (P _H2S / P _H2 ) of the partial pressure of hydrogen sulfide (P _H2S ) to the partial pressure of hydrogen (P _H2 ) is preferably controlled to 0.0003 to 0.0005.

When a reaction gas containing by-product gas, hydrogen sulfide, and oxygen is introduced into the reaction unit 2200, the first agglomerated material and the reaction gas react in the reaction unit 2200. That is, at least one of iron (Fe) and iron oxide (FeO, Fe ₂ O ₃ , etc.) contained in the first compacted material reacts with the hydrocarbon contained in the reaction gas (see Scheme 1 and Scheme 2). Through this reaction, iron carbide (Fe ₃ C) is generated inside the first compacted material. That is, at least one iron (Fe) among the metallic iron (Metal) and iron oxide (FeO, Fe ₂ O ₃ , etc.) contained in the first compacted material reacts with the hydrocarbon contained in the reaction gas, thereby producing metallic iron (Metal). ) and iron oxides (FeO, Fe ₂ O ₃ , etc.) are converted to iron carbide (Fe ₃ C). Accordingly, a second compacted material containing iron carbide (Fe ₃ C) is produced. The second compacted body produced in the reaction unit 2200 is supplied to the cooling unit 4100 of the compacted substance supply device 4000, cooled, and then stored in the compacted substance storage unit 4200.

Additionally, the reaction gas supplied to the reaction unit 2200 can be reformed into a gas containing carbon monoxide (CO) and hydrogen (H) using the first compacted material as a catalyst (see Scheme 3 and Scheme 4). The reaction gas reformed in the reaction unit 2200 is supplied to the heating unit 1200 of the reduced iron production device 1000 through the reducing gas supply unit 2500, heated, and then supplied to the reduction unit 1100 to produce reduced iron. It is used.

While producing the second compacted material in this way, iron source and coke are prepared on the one hand. At this time, sintered ore manufactured by sintering iron ore as the iron source can be prepared. When the sintered ore, coke, and secondary compacted material are prepared, they are introduced into the melting device 3000, for example, into the upper part of a blast furnace. At this time, the discharge amount of the second compacted material stored in the compacted material storage unit 4200 is controlled by the cutting unit 4300. And the second compacted material discharged out of the cutout part 4300 can be input into the upper part of the blast furnace through the third transfer part 4310. Then, high-temperature gas is injected into the lower part of the blast furnace. At this time, the high temperature gas may be a gas containing carbon monoxide, carbon dioxide, hydrogen, and nitrogen.

When sintered ore, coke, and secondary compacted material are introduced into the upper part of the blast furnace, and high-temperature gas is introduced into the lower part of the blast furnace, the coke is burned by the high-temperature gas. Then, iron ore is reduced and melted by the heat generated by the combustion of coke and carbon monoxide (CO) to produce molten iron, or molten iron.

In the above, it was explained that both sintered ore and compacted material, which are iron sources, are introduced into the melting device 3000. However, the secondary compacted material may be input as the iron source, and sintered ore or iron ore may not be input. In other words, molten iron may be manufactured by inputting only the second compacted material without using sintered ore or iron ore as the iron source inputted into the melting device.

In embodiments of the present invention, the reactivity of the compacted body can be improved by producing the compacted body by adding torrefied biomass raw material to reduced iron. Additionally, the compacted material according to the embodiment can be used as a substitute for iron ore used as an iron source when manufacturing molten iron. Accordingly, the amount of coke input for manufacturing molten iron can be reduced. To be more specific, the reactivity of a compacted product manufactured by adding more carbon (C) to reduced iron is higher than that of a compacted product manufactured using only reduced iron. Therefore, compared to using a compacted material manufactured using only reduced iron as an iron source, when using a compacted material manufactured by adding more carbon (C) to reduced iron as an iron source, the amount of coke input for reduction and melting of the iron source must be adjusted. can be reduced.

In addition, carbon dioxide (CO ₂ ) generated when biomass raw materials are burned is carbon dioxide (CO ₂ ) absorbed by plants, which are the raw materials for biomass, during photosynthesis. And, carbon dioxide (CO ₂ ) usually emitted from biomass is not considered an environmental pollutant. Accordingly, even if carbon dioxide (CO ₂ ) is generated due to combustion of biomass raw materials by using a compacted material containing biomass raw materials as a substitute for coke, this is not a factor that further worsens air pollution. In addition, when a compacted material containing biomass raw materials is used as a substitute for iron ore when manufacturing molten iron, the input amount of coke can be reduced. Accordingly, the amount of carbon dioxide (CO ₂ ) generated due to combustion of coke during the production of molten iron can be reduced. Therefore, by using compacted material containing biomass raw materials as an iron source, worsening of atmospheric pollution due to carbon dioxide (CO ₂ ) can be suppressed or prevented.

1000: Reduced iron production device 1100: Reduction unit
2000: Compacted material manufacturing equipment 2100: Compacted material manufacturing department
2110: Torrefaction machine 2130: Molding machine

Claims (19)

A compacted material manufacturing device including a compacted material production unit capable of producing a compacted material,
The compacted material manufacturing department,
A torrefaction device provided with a space for heating and torrefaction biomass raw materials; and
A compacted body manufacturing apparatus including a molding machine capable of mixing the biomass raw material torrefied in the torrefaction machine and reduced iron and forming the compacted body into a compacted body. In claim 1,
The first compacted material can be supplied from the compacted material manufacturing unit, and the first compacted material is reacted with a reaction gas to convert the first compacted material into a second compacted material containing iron carbide (Fe ₃ C). A compacted material manufacturing apparatus including a reaction unit installed to enable In claim 1,
The compacted material manufacturing department,
A reduced iron storage device that stores the reduced iron; and
It includes a biomass storage device that receives and stores the torrefied biomass raw material from the torrefaction device,
The molding machine is a compacted material manufacturing device installed to receive reduced iron and biomass raw materials from the reduced iron storage unit and the biomass storage unit. In claim 1,
The compacted material manufacturing department,
A carbon-containing by-product storage device capable of storing at least one of a carbon-containing by-product generated in a coke production device, a carbon-containing by-product generated in a coke digestion device, and a carbon-containing by-product generated in a melting device for producing molten iron,
The compacted body manufacturing device is installed so that the molding machine can receive carbon-containing by-products from the carbon-containing by-product storage. A reduced iron production device capable of producing reduced iron by reducing raw materials containing iron ore;
A compacted material manufacturing device installed to receive reduced iron from the reduced iron manufacturing device and to produce a compacted material by mixing the reduced iron with a biomass raw material; and
A molten iron manufacturing facility comprising a melting device capable of receiving a compacted material from the compacted material manufacturing device and melting the compacted material to produce molten iron. In claim 5,
The compacted material manufacturing device,
A compacted material manufacturing unit equipped with a torrefaction machine capable of torrefaction of the biomass raw material and a molding machine for mixing the torrefied biomass raw material produced in the torrefaction machine with reduced iron and manufacturing a compacted material using the mixture. ; and
A molten iron manufacturing facility comprising: a reaction unit installed to receive the compacted material from the compacted material production unit and to react the compacted material with a reaction gas to increase the content of iron carbide (Fe ₃ C). In claim 6,
A molten iron manufacturing facility comprising a reaction gas supply device installed to recover by-product gas generated when torrefaction of biomass raw materials in the torrefaction unit and supply it to the reaction unit. In claim 7,
The reaction gas supply device,
A gas recovery unit installed to recover by-product gas generated from the torrefaction unit;
a heating unit installed in the gas recovery unit to heat the by-product gas passing through the gas recovery unit;
A molten iron manufacturing facility comprising: a gas supply unit installed to supply by-product gas heated in the heating unit to the reaction unit. Process of producing reduced iron;
Process of preparing biomass raw materials;
A process of increasing the content of fixed carbon by heating the biomass raw material;
A process of preparing a mixture by mixing the reduced iron and heated biomass raw materials; and
A process of producing a compacted body by molding the mixture; A method for producing a compacted body comprising: In claim 9,
The biomass raw material includes at least one of a lignocellulosic biomass raw material and an herbaceous biomass raw material,
The lignocellulosic biomass raw material includes at least one of chips, charcoal, briquettes, and pellets containing wood,
The herbaceous biomass raw material includes at least one of rice straw and rice husk. In claim 9,
In preparing the mixture,
A method for producing a compacted material, wherein the content of fixed carbon is mixed to 2% by weight to 5% by weight with respect to the entire compacted material. In claim 9,
The process of increasing the content of fixed carbon by heating the biomass raw material includes the process of torrefaction of the biomass raw material,
In preparing the mixture,
A method of producing a compacted material in which the torrefied biomass raw material is mixed so that the total amount of the mixture is more than 0% by weight and 10% by weight or less. In claim 9,
The process of increasing the content of fixed carbon by heating the biomass raw material includes the process of torrefaction of the biomass raw material,
The process of preparing the mixture includes further mixing carbon-containing by-products generated during the steelmaking process,
In preparing the mixture,
A method of producing a compacted material in which the combined content of the torrefied biomass raw material and the carbon-containing by-product is mixed so that the total content of the mixture is more than 0% by weight and 10% by weight or less. In claim 13,
In preparing the mixture,
A method of producing a compacted material in which the content of the torrefied biomass raw material is mixed so that the content of the torrefied biomass raw material is greater than the content of the carbon-containing by-product in the entire mixture. The method of any one of claims 9 to 14,
The first compacted body manufactured by molding is reacted with a reaction gas to convert the iron (Fe) contained in the metallic iron and iron oxide contained in the first compacted body into iron carbide (Fe ₃ C), thereby producing iron carbide ( A method for producing a compacted material comprising the step of producing a second compacted material containing Fe ₃ C). A process of producing compacted material using a mixture containing reduced iron and torrefied biomass raw materials; and
A method of manufacturing molten iron comprising the process of introducing the compacted material into a melting device and melting the compacted material. In claim 16,
The process of producing the compacted material includes reacting the compacted material with a reaction gas containing hydrocarbon to produce a compacted material containing iron carbide (Fe ₃ C),
A method of producing molten iron, wherein the compacted material containing iron carbide (Fe ₃ C) is introduced into the melting device. In claim 17,
The reaction gas is a method of producing molten iron including a by-product gas generated when torrefaction of biomass raw materials. In claim 16,
Including the process of introducing iron ore into the melting device,
A method of producing molten iron in which the iron ore is melted together in melting the compacted material.

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