KR101316382B1 - Integrated iron and steelmaking system and method - Google Patents

Abstract

The present invention relates to an integrated steel making system and a co-milling method, and more particularly, to an integrated steel making system and an integrated steel making method which are capable of reducing the amount of environmental pollutants generated in a raw material processing and a ladle- And a consistent steel making method.
According to an aspect of the present invention, each of the reduced flow iron ore, including one or more flow reduction reactor to reduce the reduced iron ore manufacturing reduced iron ore comprising a first flow reduction reactor facility and a second flow reduction reactor facility configured to produce reduced iron ore Device; A first bulking device and a second bulking device configured to produce the bulk reducing iron by receiving and bulking the reduced iron ore from the first and second flow reducing facility; And a steelmaking apparatus including a melting furnace for melting molten mass reduced iron that is agglomerated in the first massaging apparatus and a molten iron for producing molten iron; and a steelmaking apparatus for receiving molten iron and mass reduced iron produced in the apparatus for manufacturing molten steel. An integrated steelmaking system is provided.
According to the present invention, it is possible to provide an integrated steelmaking system and an integrated steelmaking method using the same, which can flexibly cope with the raw material environment and can significantly reduce environmental pollution.

Description

[0001] INTEGRATED IRON AND STEELMAKING SYSTEM AND METHOD [0002]

The present invention relates to an integrated steelmaking system and an integrated steelmaking method, and more particularly, to an environmentally friendly integrated steelmaking system by not only significantly reducing the amount of environmental pollutants generated in raw material processing and steel making processes, but also reducing energy consumption. And an integrated steelmaking method.

Generally, molten steel is manufactured by refining in a converter using molten iron produced in a blast furnace as a main raw material.

Currently, there has been no development of a boiler process that exceeds the blast furnace process in terms of energy efficiency and productivity in the production of charcoal. However, in such blast furnace process, the carbon source used as the fuel and the reducing agent should be dependent on the coke treated with the specific cokes, Is largely dependent on sinter ores that have undergone a series of agglomerating processes.

In other words, the present blast furnace process necessarily involves raw material pre-treatment equipment such as coke making equipment and sintering equipment, which inevitably necessitates the construction of additional facilities in addition to the blast furnace facility, resulting in a great cost burden for the equipment.

Further, in the raw material preliminary treatment facility as described above, since environmental pollutants such as SOx, NOx, or dust are generated considerably, a separate facility for purification treatment thereof is required, and in particular, And the cost of investment for disposal facilities to cope with this, the competitiveness of charcoal production through current blast furnace process is decreasing.

Meanwhile, many other processes have been researched and developed in order to solve the problems occurring in the above-mentioned blast furnace process. In the currently-developed refining process, general coal is directly used as a fuel and a reducing agent, % Of iron ore is used as a raw material to produce molten iron, which is known as an excellent production process.

However, the quantity of molten iron that can be supplied by one unit equipment implementing the process is still large enough to produce molten blast furnace, for example, 3 million tons or more, preferably 4 million tons or more. There is a disadvantage in that it is not enough compared to the blast furnace, and therefore, in order to produce the same amount of molten iron as the blast furnace, a plurality of melt reduction facilities must be installed, and accordingly, there may be a problem in that there is a shortage of steelworks.

In addition, the melt reduction facility or blast furnace facility is a facility for reducing ore using coal-based reducing agent, and a large amount of carbon dioxide is emitted as a result of the reduction reaction, which is often pointed out as a cause of accelerating global warming.

According to one aspect of the present invention, there is provided an environment-friendly integrated steelmaking system and integrated steelmaking method by varying the route of pig iron supplied in the molten reduction process, which is a molten iron manufacturing equipment, and by treating the pig iron supplied from it with energy efficiency.

Further, according to another aspect of the present invention, there is provided an integrated steel making system and an integrated steel making method for obtaining a steel sheet by performing casting and rolling in a single process of molten steel produced from the above-described integrated steel making system and integrated steel making method.

According to yet another aspect of the present invention, there is provided a highly productive integrated steelmaking system and an integrated steelmaking method having a production capacity of 3 million tons or more, preferably 4 million tons or more.

According to yet another aspect of the present invention, there is provided an environment-friendly integrated iron and steel manufacturing system and minimized carbon dioxide emissions.

One embodiment of the integrated steelmaking system for solving the problems of the present invention is reduced iron ore comprising a first flow reduction reactor facility configured to reduce the iron ore to reduce iron ore including one or more flow reduction reactors to produce reduced iron ore Manufacturing apparatus; A hydrogen reducing gas supply facility connected to the first flow reducing reactor facility in a gas communication relationship to supply hydrogen reducing gas; A first bulking device configured to produce a bulky reducing iron by agglomerating and receiving the reduced iron ore from the first flow reduction facility; And a smelting furnace including a melting furnace for melting molten mass reduction iron massified in the first massaging apparatus to produce molten iron.

It may include a steel making apparatus for manufacturing molten steel by receiving the molten iron manufactured by the iron making apparatus.

Another embodiment of the integrated steelmaking system of the present invention includes a first flow reduction reactor facility and a second flow reduction reactor facility configured to produce reduced iron ore by reducing the iron ore, respectively, including one or more flow reduction reactors. Reduced iron ore manufacturing apparatus; A hydrogen-based reducing gas supply facility connected to the first flow-reduction facility or the second flow-reduction facility in a gas communication relationship to supply hydrogen-based reducing gas; A first bulking device and a second bulking device configured to produce the bulk reducing iron by receiving and bulking the reduced iron ore from the first and second flow reducing facility; And a steelmaking apparatus including a melting furnace for melting molten mass reduced iron that is agglomerated in the first massaging apparatus and a molten iron for producing molten iron; and a steelmaking apparatus for receiving molten iron and mass reduced iron produced in the apparatus for manufacturing molten steel. can do.

At this time, the final flow path of the first flow path and the furnace is connected to the gas communication through the gas supply pipe, the first flow path of the first flow path and the second flow path of the second flow path equipment The flow reduction path is preferably connected in a gas communication relationship through a reducing gas connecting pipe.

And at least one of the first flow return reactor and the second flow return reactor includes a circulation pipe, and an initial flow reduction path of the at least one facility includes the final flow of the at least one facility through the circulation pipe. It is advantageous to be connected in a gas communication relationship to the flow return path.

In addition, the final flow path and the melting furnace of the first flow path reactor equipment is connected in a gas communication relationship through the gas supply pipe, the flow path of the flow path of the first flow path equipment and the second flow path reduction equipment The furnace is connected in a gas communication relationship through a reducing gas connecting pipe, the reducing gas connecting pipe is preferably connected to the circulation pipe of at least one facility.

In addition, it is preferable that three or four flow reduction paths of the first flow reduction reactor are made, and four flow reduction paths of the second flow reduction path are provided.

In addition, it is advantageous that at least one of the circulation tubes is provided with at least one of a carbon dioxide remover and a heater.

In addition, it is preferable that the exhaust gas of the first flow reduction reactor is supplied to the second flow reduction reactor through a reducing gas connecting pipe.

At this time, it is more preferable that the damping device is further provided with the reducing gas connection pipe.

In addition, at least one of the circulation pipes is preferably provided with at least one of a carbon dioxide removal device and a heater.

In addition, the steelmaking apparatus includes a converter or an electric furnace, and the converter or the electric furnace and the second blocker are effectively connected in a block of reduced iron communication through the block of reduced bulk iron transfer pipe.

In addition, the bottom of the converter is preferably provided with a nozzle configured to supply fuel and oxygen (O ₂ ), the upper portion of the converter is preferably provided with a lance for supplying an oxygen-containing gas.

And, the oxygen-containing gas is advantageously heated air.

In addition, it is preferable to further include a slab casting apparatus is directly connected to the continuous casting machine and the rolling device for casting molten steel produced in the steelmaking apparatus.

In addition, the continuous casting machine is effective to produce a slab with a thickness of 30 ~ 150mm.

And, the peripheral speed of the continuous casting machine is advantageously 4 ~ 15mpm.

In addition, the rolling apparatus includes a roughing mill and a finishing mill, it is preferable that the steel sheet heating means is further included between the roughing mill and the finishing mill.

In addition, the coil box for winding and storing the steel sheet in the coil state between the steel plate heating means and the finishing mill is preferably further included.

In accordance with yet another embodiment of the present invention, the integrated steelmaking method includes reducing iron ore in a first flow reduction reactor, and manufacturing reduced iron ore, respectively, in the first flow reduction reactor. Using hydrogen-based reducing gas as part; In the first block device, the step of receiving the powdered iron ore reduced in the first flow reduction facility to agglomerated to produce a bulk reducing iron; And a steelmaking step including a molten iron manufacturing step of melting molten mass reduced iron in the first massifying device to produce molten iron and a steelmaking step of receiving molten iron prepared in the ironmaking step. It may include.

According to another preferred aspect of the present invention, there is provided a method for manufacturing a reduced iron ore by reducing iron ore in each of the first and the second flow reduction reactor facilities. Using the hydrogen-based reducing gas as part or all of the reducing gas in the facility or the second flow reduction reactor facility; In the first block and the second block, the first flow reducing facility and the second flow reducing facility is reduced by receiving the iron ore reduced by the step of producing the mass reduction iron; And a molten iron manufacturing step including a molten iron manufacturing step of melting the bulky reduced iron which has been agglomerated in the first blocker to produce molten iron and receiving molten steel and the reduced iron which are manufactured in the iron making step to manufacture molten steel. It may include a steel making step.

In this case, it is preferable that the reduction of iron ore in the first flow reduction reactor is performed so that the reduction rate is 50 to 80%, and the reduction of iron ore in the second flow reduction reactor is performed so that the reduction rate is 80 to 95%.

In addition, it is effective that the molten iron and the bulk reduction iron supplied to the steelmaking step is charged at a charge of 40 to 80% by weight molten iron and 20 to 60% by weight of the bulk reduction iron.

In addition, the steelmaking step is advantageously performed by a converter or an electric furnace.

In addition, it is preferable to supply the exhaust gas discharged from the first flow reduction reactor to the second flow reduction reactor to use as reducing gas.

At this time, it is more preferable to further include the step of removing the exhaust gas discharged from the first flow reduction reactor.

In addition, circulating the exhaust gas discharged from at least one of the first flow reduction reactor facility and the second flow reduction reactor facility to the reducing gas, removing the circulated gas by the carbon dioxide removal unit and the temperature by the heater After processing by one of the steps of adjusting the, it is preferable to supply the at least one facility or another facility.

In addition, the bulk reducing iron is effectively charged in the melting furnace or steelmaking step at a high temperature of 500 ~ 800 ℃.

In addition, when there is a failure in the first flow reduction facility, it is advantageous to manufacture a molten iron by supplying some or all of the bulk reducing iron produced in the second flow reduction facility.

It is also advantageous to supply fuel and oxygen (O ₂ ) at the bottom of the converter, and to supply heated oxygen-containing gas at the top of the converter when manufacturing molten steel in the converter.

In addition, the oxygen-containing gas is preferably heated air.

In addition, it is effective to further include a slab casting step is directly connected to the continuous casting step and the rolling step of casting the molten steel produced in the steelmaking step.

At this time, the continuous casting machine is preferably to produce a slab of 30 ~ 150mm thickness.

The rolling step may include a rough rolling step and a finishing rolling step, and a steel sheet heating step may be further included between the rough rolling step and the finishing rolling step.

In addition, it is advantageous to further include a storage step of winding and storing the steel sheet in a coil state between the steel sheet heating step and the finishing rolling step.

According to the present invention, it is possible to provide an integrated steelmaking system and an integrated steelmaking method using the same, which can flexibly cope with the raw material environment and can significantly reduce environmental pollution.

In addition, even when compared to an integrated steelmaking system or an integrated steelmaking method including an existing blast furnace, it is possible to provide an integrated steelmaking system and an integrated steelmaking method using the same. In addition, there is an advantage that the generation of carbon dioxide can be reduced by replacing a portion of coal-based fuel with hydrogen-based fuel in the integrated steelmaking system.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic diagram that schematically illustrates one embodiment of a consistent steel making system in accordance with the present invention.
Figure 2 is a schematic diagram schematically illustrating another embodiment of an integrated steel making system in accordance with the present invention.
Figure 3 is a schematic diagram that schematically illustrates yet another embodiment of an integrated steel making system in accordance with the present invention.
4 is a schematic diagram schematically showing another example of the implementation of the integrated steel making system in accordance with the present invention.
5 is a schematic diagram schematically showing another example of the implementation of the integrated steel making system in accordance with the present invention.
6 is a schematic diagram schematically showing another example of the implementation of the integrated steel making system in accordance with the present invention.
FIG. 7 is a schematic diagram illustrating a system in which a slab casting apparatus is further included in the integrated steelmaking system of FIG. 1.
FIG. 8 is a schematic diagram illustrating a system in which a slab casting apparatus is further included in the integrated steelmaking system of FIG. 2.
FIG. 9 is a schematic diagram illustrating a system in which a slab casting apparatus is further included in the integrated steelmaking system of FIG. 3.
FIG. 10 is a schematic diagram illustrating a system in which a slab casting apparatus is further included in the integrated steelmaking system of FIG. 4.
FIG. 11 is a schematic diagram illustrating a system in which a slab casting apparatus is further included in the integrated steelmaking system of FIG. 5.
FIG. 12 is a schematic diagram illustrating a system in which a slab casting apparatus is further included in the integrated steelmaking system of FIG. 6.

Hereinafter, the present invention will be described.

As used herein, the term "integrated steel" refers to a steelmaking method including both a process of producing molten iron from iron ore as a raw material and a process of producing molten steel from the molten iron, wherein the integrated steelmaking system comprises: And the steelmaking process for producing molten steel.

The steelmaking step is performed by a melting reduction facility (melting furnace) for reducing molten iron ore to produce molten iron. The melting furnace is subjected to flow reduction of the iron-iron ore and then agglomerated to produce agglomerated reduced iron, and to produce molten iron by reducing the agglomerated reduced iron in a melting furnace.

One preferred embodiment of the integrated steelmaking system of the present invention is shown in FIG.

As shown in FIG. 1, the integrated steelmaking system 1 of the present invention includes a steelmaking apparatus 10 and a steelmaking apparatus 20 (in the drawing, a converter is taken as one preferred example, which will be mainly described below).

The iron making apparatus 10 includes a reduced iron ore manufacturing apparatus 11 configured to reduce the iron ore to produce reduced iron ore; An agglomerating device (13) for agglomerating the reduced iron ores in the reduced iron ore producing device; And a melting furnace (12) for melting the agglomerated reduced iron in the agglomerating device (13) to produce a molten iron.

The reduced iron ore manufacturing apparatus 11 includes a first flow reduction reactor (111), each of the first flow reduction reactor (111) includes at least one flow reduction reactor.

The first flow reduction reactor (111) is a facility for reducing spectroscopic stones while flowing with gas. The minute ores undergo a stepwise reduction process in a series of fluidization furnaces constituting the fluidization facility. That is, the fluidization furnace is a place where the injected spectroscopy is reduced in stages by the reducing gas, but the number is not limited, but it is preferable that two or more are included for sufficient reduction, and more than three are included. desirable. As described above, the first flow reduction reactor (111) is thereafter for supplying the reduced reduction iron to the melting furnace (melting reduction facility) 12 through the first bulking device (13), in the melting furnace (12) Since additional reduction is made, three flow reduction paths 1111, 1112, 1113, and 1114 are sufficient, and four are more preferable.

However, as mentioned above, it is not necessary to limit the number of the flow reduction path of the flow reduction facility (111).

In FIG. 1, the first flow reduction path facility 111 includes four flow reduction paths 1111, 1112, 1113, and 1114.

In the fluidized-bed reactors 1111, 1112, 1113 and 1114, a gas distributor (not shown) for dispersing the gas as in a conventional fluidized-bed reactor may be provided.

The bulking device 13 is configured to massify by receiving the reduced iron ore reduced in the first flow reduction facility (111).

The first blocker 13 is provided with a first hopper 131 for storing reduced iron ore and supplying it to the first blocker 13, and the first hopper 131 has a first reduced iron supply pipe. Through 132, the final flow reduction path 1111 of the first flow reduction path facility 111 is connected to the reduced iron ore communication relationship.

The melting furnace 12 is configured to melt agglomerated reduced iron that is agglomerated in the first agglomeration apparatus 13 to produce molten iron.

The melting furnace 12 is connected in a gas communication relationship through the gas supply pipe 121 and the final flow reduction path 1111 of the first flow reduction facility (111) of the reduced iron ore manufacturing apparatus (11), 1 The flow reduction paths 1111, 1112, 1113 and 1114 of the flow return path facility 111 are interconnected in a gas communication relationship through a gas supply pipe (not shown).

The reducing gas supplied to the final fluidized-bed reactor 1111 through the gas supply pipe 121 is supplied to the first fluidized-bed reactor 1114 through the fluidized-bed reactors 1111, 1112, 1113, and 1114 in order.

On the other hand, the iron ore is first supplied to the first flow reduction path (1114), and then supplied to the final flow reduction path (1111) through the flow reduction paths (1114, 1113, 1112, 1111), thus the flow reduction paths ( Through 1114, 1113, 1112, 1111, the iron ore is reduced by the reducing gas.

In the present invention, the hydrogen-based reducing gas supplied from the hydrogen-based reducing gas supply facility 15 may be used as part or all of the reducing gas of the first flow reducing reactor equipment 111. In this case, there is an advantage that can reduce the amount of coal-based reducing agent used in the flow furnace. That is, when the reducing gas for reducing the iron ore of the first flow reduction reactor (111) is covered with only the flue gas of the melting furnace, the amount of coal-based reducing agent used in the melting furnace is increased in order to leave a large amount of reducing gas in the flue gas of these facilities. Inevitably, there is a problem that the amount of carbon dioxide generated throughout the facility increases. Therefore, in the present invention, the hydrogen-based reducing gas supplied from the hydrogen-based reducing gas supply facility 15 is used as all or part of the reducing gas of the first flow reduction / reduction facility 111. Therefore, the hydrogen-based reducing gas supply facility 15 is connected to the first flow reduction path facility 111 through the hydrogen-based reducing gas supply pipe 151 in a gas communication relationship. Preferably, the hydrogen-based reducing gas supply facility (15) is connected to the final flow reduction path 1111 of the first flow reduction reactor (111). In the present invention, the hydrogen-based reducing gas supplied by the hydrogen-based reducing gas supply facility 15 means a gas containing 70% or more of hydrogen in a volume ratio. As the hydrogen-based reducing gas, in addition to pure hydrogen, hydrogen may be modified by reforming one or more kinds of reformed gases such as coke flue gas (COG), liquefied natural gas (LNG), and Finex flue gas (FOG). Reforming gas may be used so that it contains 70% or more by volume ratio.

If all of the reducing gas of the first flow reduction reactor (111) is not the reducing gas supplied from the hydrogen-based reducing gas supply (15), the remaining reducing gas is supplied directly from the melting furnace or a separate reduction It can be supplied by a gas supply line. However, even in such a case, the reducing gas by the above-described hydrogen-based reducing gas may be supplied to the first flow reduction reactor facility 111.

In addition, through the more efficient use of the exhaust gas, as described later, the first flow return path 1114 and the final flow return path 1111 of the first flow return path facility 111 are connected to the gas by the circulation pipe 1115. It is preferable that the flue gas generated in the first flow reduction reactor of the at least one facility is connected to the final flow reduction reactor. In this case, the hydrogen-based reducing gas supply pipe 151 may also be connected to the circulation pipe 1115.

That is, in one preferred embodiment of the present invention, the final flow return path 1111 and the first flow return path 1114 of the first flow return path facility 111 are connected to the gas communication path through the first circulation pipe 1115. Can be connected.

The first circulation pipe 1115 may further include a carbon dioxide removal device 118, and the carbon dioxide removal device 118 may be provided with an exhaust gas discharge pipe 1181 for discharging the exhaust gas.

In addition, the first circulation pipe 1115 between the carbon dioxide removal unit 118 and the final flow reduction path 1111 may be further provided with a heater (not shown) for raising the temperature of the circulating gas.

As described above, the exhaust gas discharged from the first flow reduction reactor 111 is provided to the final flow reduction reactor 1111 after the carbon dioxide removal device 118 is provided in the first circulation pipe 1115 to reduce gas. To be recycled. Further, if necessary, the temperature of the circulating gas can be controlled by providing the heater as described above.

The steelmaking step after the above-mentioned steelmaking step may be carried out by a steelmaking apparatus including a refining facility such as a converter or an electric furnace.

The converter is a device for converting oxygen into molten steel by supplying oxygen or an oxygen-containing gas into the furnace to burn the carbon in the molten iron to convert the molten iron into the molten steel at the carbon saturation level. The carbon or other oxidizing component is converted into molten steel by the combustion heat, Is also a device for simultaneously raising temperature.

There are various kinds of converters, but they are all usable in the present invention. That is, the present invention can be used in the present invention regardless of the difference in the manner of cigarettes, such as the outcrossing, the low-odor or the upside-down combination, and the different styles depending on the design method of each steelmaker.

However, since the main raw material supplied in the steelmaking step includes not only hot molten iron but also a bulk reducing iron as in another preferred embodiment of the present invention described below, or may include scrap as in another embodiment, It is more preferable to use a method with higher thermal efficiency, and in a preferred embodiment of the present invention, the steelmaking apparatus more preferably includes a converter in the following manner.

That is, in a more preferable example of the present invention, the converter 20 is configured to manufacture molten steel using the molten iron manufactured in the apparatus 10 as described above as a main raw material, respectively, in the upper and lower portions of the converter 20. 21 and the nozzle 22 are provided. At this time, if necessary, in addition to the molten iron, additional raw materials such as scrap may be charged. The nozzle provided in the lower portion of the converter serves to refine the molten steel by blowing oxygen. At this time, fuel which can act as a heat source together with oxygen can be blown. The fuel may include coal, combustible gas, etc., but is not necessarily limited thereto. In addition, the fuel may be blown together with oxygen, or may be blown by a carrier gas such as nitrogen to a separate nozzle. In the lower part of the converter, in addition to the fuel, it is possible to control the base of slag such as quicklime and the like, which may act as a nucleus for decarburization, and may be blown with oxygen or by a separate carrier gas.

In addition, the lance 21 may inject a gas containing oxygen, preferably air into the furnace. The oxygen-containing gas injected into the furnace serves to additionally supply heat to the molten steel by post combustion of carbon monoxide produced by the decarburization reaction of the molten steel. At this time, a heating means may be added to the supply path of the oxygen-containing gas in order to further increase the thermal efficiency of the oxygen-containing gas, as the heating means may be any one that is commonly used, more preferably discharged from the converter A heat exchanger type heating device 211 for exchanging heat of waste gas may be used.

The converter may have a method of blowing oxygen through the nozzle 22 at the bottom as described above, but may also refine the molten steel by blowing oxygen through the above-described lance 21 or a separate lance (not shown). Has already been revealed earlier.

Another example of the integrated steelmaking system of the present invention is shown in FIGS. 2 and 3.

The integrated steel making system 2 shown in FIG. 2 is similar to the integrated steel making system 1 shown in FIG. 1 except that the first fluidized-bed reactor facility 111 includes three fluidized-bed reactors 1111, 1112, (1).

The integrated steelmaking system 3 shown in FIG. 3 is substantially the same as the integrated steelmaking system 1 shown in FIG. 1 except that an electric furnace 20-1, rather than the converter 20, is used as the steelmaking apparatus. In addition, the number of melt reduction furnaces described in the integrated steelmaking system 3 shown in FIG. 3 may be changed to be the same as in FIG. 2.

However, as described above, since the amount of molten iron that can be produced in the smelter is not sufficient compared to the blast furnace, when only the molten iron produced in the smelting furnace is used, it is necessary to install a plurality of facilities, so that the productivity is not bad and the site of the steelworks is difficult to secure. Secondary problems can arise.

In one preferred embodiment of the present invention, the steelmaking apparatus may further have one or more processes for bulking the iron ore after mass reduction to overcome these disadvantages. In other words, the reduced reduction iron produced by the additional agglomeration process is not melted in the melting furnace and further reduction occurs in this process to produce molten iron, but undergoes a process of reduction in a subsequent steelmaking step, resulting in molten steel. .

Therefore, embodiments of the present invention described below are prepared by agglomerated the reduced iron ore prepared by reducing the iron ore to produce a bulk reducing iron, and then the molten iron prepared by melting a part of the bulk reducing iron and the rest of the mass reduced iron. The present invention relates to an integrated steelmaking system for producing molten steel using a main raw material in a converter and an integrated steelmaking method using the same.

Another embodiment of the integrated steelmaking system of the present invention is shown in FIG.

As shown in FIG. 4, the integrated steelmaking system 1 of the present invention includes a steelmaking apparatus 10 and a steelmaking apparatus 20 (which includes a converter as one preferred example in the drawing, which will be described below).

The iron making apparatus 10 includes a reduced iron ore manufacturing apparatus 11 configured to reduce the iron ore to produce reduced iron ore; Agglomeration apparatus (13, 14) for massifying the reduced iron ore reduced in this reduced iron ore manufacturing apparatus; And a melting furnace 12 for melting molten iron which has been agglomerated in the bulking devices 13 and 14 to produce molten iron.

The reduced iron ore manufacturing apparatus 11 includes a first flow reduction reactor (111) and a second flow reduction reactor (112), and the first flow reduction reactor (111) and the second flow reduction reactor (11) 112 each includes one or more flow reduction reactors.

The first 111 and the second flow reduction reactor facility 112 is a facility for reducing spectroscopy while flowing with gas. The minute ores undergo a stepwise reduction process in a series of fluidization furnaces constituting the fluidization facility. That is, the fluidization furnace is a place where the injected spectroscopy is reduced in stages by the reducing gas, but the number is not limited, but it is preferable that two or more are included for sufficient reduction, and more than three are included. desirable. As described above, the first flow reduction reactor (111) is thereafter for supplying the reduced reduction iron to the melting furnace (melting reduction facility) 12 through the first bulking device (13), in the melting furnace (12) Since additional reduction is made, three flow reduction paths 1111, 1112, 1113, and 1114 are sufficient, and four are more preferable.

Since the second flow reduction reactor facility 112 manufactures the bulk reducing iron through the second bulking device 14 and directly inputs it to the converter 20 without additional melt reduction in the melting furnace 12, the second flow reducing reactor facility 112 is used. More preferably, four flow reduction paths 1121, 1122, 1123, and 1124 included in the flow reduction path facility 112 are disposed for a sufficient reduction.

However, as mentioned above, it is not necessary to limit the number of flow reduction paths of each flow reduction facility (111, 112).

In FIG. 4, the first flow reduction path facility 111 includes four flow reduction paths 1111, 1112, 1113 and 1114, and the second flow reduction path facility 112 includes four flow reduction paths 1121. , 1122, 1123, and 1124 are shown.

In the flow reduction paths 1111, 1112, 1113 and 1114 and the flow reduction paths 1121, 1122, 1123 and 1124, gas dispersion plates (not shown) for dispersing gas are provided as in the general flow reduction paths. It may be provided.

The mass converters 13 and 14 are configured to mass-reduce the reduced iron ore reduced by the first fluidized-circuit reactor 111 and the second fluidized-bed reactor. And a second bulking device 14 configured to receive and massify the reduced reduced iron ore from the facility 112.

The first blocker 13 is provided with a first hopper 131 for storing reduced iron ore and supplying it to the first blocker 13, and the first hopper 131 has a first reduced iron supply pipe. Through 132, the final flow reduction path 1111 of the first flow reduction path facility 111 is connected to the reduced iron ore communication relationship.

In addition, the second blocker 14 is provided with a second hopper 141 for storing reduced iron ore and supplying the second blocker 14 to the second blocker 141. Through the supply pipe 142 is connected to the reduced flow iron ore and the final flow reduction path 1121 of the second flow reduction facility (112).

The melting furnace 12 is configured to melt agglomerated reduced iron that is agglomerated in the first agglomeration apparatus 13 to produce molten iron.

The melting furnace 12 is connected in a gas communication relationship through the gas supply pipe 121 and the final flow reduction path 1111 of the first flow reduction facility (111) of the reduced iron ore manufacturing apparatus 10, 1 The flow reduction paths 1111, 1112, 1113 and 1114 of the flow return path facility 111 are interconnected in a gas communication relationship through a gas supply pipe (not shown).

The reducing gas supplied to the final fluidized-bed reactor 1111 through the gas supply pipe 121 is supplied to the first fluidized-bed reactor 1114 through the fluidized-bed reactors 1111, 1112, 1113, and 1114 in order.

On the other hand, the iron ore is first supplied to the first flow reduction path (1114), and then supplied to the final flow reduction path (1111) through the flow reduction paths (1114, 1113, 1112, 1111), thus the flow reduction paths ( Through 1114, 1113, 1112, 1111, the iron ore is reduced by the reducing gas.

In each of the flow reduction paths 1121, 1122, 1123, and 1124 of the second flow reduction path facility 112, as described below, the iron ore in the same manner as each flow reduction path of the first flow reduction path facility 111; Reduction may occur.

That is, the flow reduction paths 1121, 1122, 1123, and 1124 of the second flow reduction path facility 112 are interconnected in a gas communication relationship through a gas supply pipe (not shown).

The reducing gas is first supplied to the final flow reduction path 1121 and then to the initial flow reduction path 1124 via the flow reduction paths 1121, 1122, 1123, and 1124.

On the other hand, the iron ore is first supplied to the first flow reduction path (1124), and then supplied to the final flow reduction path (1121) through the flow reduction paths (1124, 1123, 1122, 1121), thus the flow reduction paths ( Through 1124,1123,1122,1121, the iron ore is reduced by the reducing gas.

In one embodiment of the present invention, the hydrogen-based reducing gas supplied from the hydrogen-based reducing gas supply facility 15 as part or all of the reducing gas of the first flow-reducing reactor 111 or the second flow-reducing reactor 112 is used. It is available. In this case, there is an advantage that can reduce the amount of coal-based reducing agent used in the flow furnace. That is, when the reducing gas for reducing the iron ore of the first flow reduction reactor (111) or the second flow reduction reactor (112) is covered by only the exhaust gas of the melting furnace or the first flow reduction reactor (111). The amount of coal-based reducing agent used in the melting furnace has to be increased in order to leave a large amount of reducing gas in the flue gas. Accordingly, in the present invention, the hydrogen-based reducing gas supplied from the hydrogen-based reducing gas supply facility 15 is used as all or part of the reducing gas of the first flow-reducing reactor facility 111 or the second flow-reducing reactor facility 112. . Therefore, the hydrogen-based reducing gas supply facility 15 is connected in a gas communication relationship with the first flow-reduction path facility 111 or the second flow-reduction path facility 112 through the hydrogen-based reducing gas supply pipe 151. Preferably, the hydrogen-based reducing gas supply facility 15 is connected to the final flow reduction path 1121 of the first flow reduction reactor (111) or the second flow reduction reactor (112). In the present invention, the hydrogen-based reducing gas supplied by the hydrogen-based reducing gas supply facility 15 means a gas containing 70% or more of hydrogen in a volume ratio. As the hydrogen-based reducing gas, in addition to pure hydrogen, hydrogen may be modified by reforming one or more kinds of reformed gases such as coke flue gas (COG), liquefied natural gas (LNG), and Finex flue gas (FOG). Reforming gas may be used so that it contains 70% or more by volume ratio.

If not all of the reducing gas of the first flow reduction reactor (111) or the second flow reduction reactor (112) is the reducing gas supplied from the hydrogen-based reducing gas supply facility (15), the remaining reducing gas May be supplied directly from the melting furnace or by a separate reducing gas supply line. However, in a more preferred embodiment to enable the efficient use of reducing gas, the first flow reduction path 1114 of the first flow reduction reactor (111) is the gas communication through the reducing gas connecting pipe (1116) It is connected to the flow return path of the two flow return path equipment (112). Through this, the exhaust gas of the first flow reduction reactor (111) can be supplied to the second flow reduction reactor (112), thereby enabling efficient use of reducing gas. However, even in this case, the reducing gas by the hydrogen-based reducing gas described above may be supplied to the first flow reduction reactor (111) or the second flow reduction reactor (112).

The reducing gas connecting pipe 1116 connects the first flow return path 1114 of the first flow return path facility 111 and the final flow return path 1121 of the second flow return path facility 112 by the first flow path. The exhaust gas of the reduction furnace equipment 111 may be supplied to the second flow reduction reactor equipment 112.

When the first flow reduction reactor (111) and the second flow reduction reactor (112) is connected in a gas communication relationship through a reducing gas connecting pipe 1116, the hydrogen-based reducing gas supply pipe 151 is the It may be connected to the final flow reduction path 1121 of the second flow reduction path facility 112 via the reducing gas connecting pipe 1116.

In addition, through more efficient use of the exhaust gas, as described below, the first flow return paths 1114 and 1124 of at least one of the first flow return path facility 111 and the second flow return path facility 112, and the The final flow return paths 1111 and 1121 of the at least one facility are connected in gas communication by circulation pipes 1115 and 1125 so that the exhaust gas generated from the first flow return path of the at least one facility is transferred to the final flow return path. It is preferred to be supplied. If the first flow reduction reactor (111) or the second flow reduction reactor (112) has a circulation pipe (1115, 1125), the reducing gas connecting pipe (1116) to the circulation pipe (1115, 1125) By being connected, the first flow reduction path 1114 of the first flow reduction path facility 111 and the final flow reduction path 1121 of the second flow reduction path facility 112 may be connected in a gas communication relationship. At this time, the hydrogen-based reducing gas supply pipe 151 may also be connected to the circulation pipe (1115, 1125). The hydrogen-based reducing gas supply pipe 151 may be directly connected to the circulation pipes 1115 and 1125, but may be connected to the second circulation pipe 1125 via the reducing gas connection pipe 1116. In addition, the reducing gas connecting pipe 1116 or the hydrogen-based reducing gas supply pipe 151 is not connected to the circulation pipe even if the circulation pipes (1115, 1125), the first of the first flow reduction facility (111) The flow reduction path 1114 and the final flow reduction path 1121 of the second flow reduction facility (112) may be directly connected, or may be connected only to some circulation pipes.

That is, in one preferred embodiment of the present invention, the final flow return path 1111 and the first flow return path 1114 of the first flow return path facility 111 are connected to the gas communication path through the first circulation pipe 1115. Can be connected.

The first circulation pipe 1115 may further include a carbon dioxide removal device 118, and the carbon dioxide removal device 118 may be provided with an exhaust gas discharge pipe 1181 for discharging the exhaust gas.

In addition, the first circulation pipe 1115 between the carbon dioxide removal unit 118 and the final flow reduction path 1111 may be further provided with a heater (not shown) for raising the temperature of the circulating gas.

As described above, the exhaust gas discharged from the first flow reduction reactor 111 is provided with the carbon dioxide removal unit 118 in the first circulation pipe 1115, after the carbon dioxide is removed, the final flow reduction reactor 1111 or the second flow reduction reactor. It is supplied to the furnace facility 112 and recycled as reducing gas. Further, if necessary, the temperature of the circulating gas can be controlled by providing the heater as described above.

Also, the final flow return path 1121 and the first flow return path 1124 of the second flow return path facility 112 may be connected in a gas communication relationship through the second circulation pipe 1125.

The second circulation pipe 1125 may be provided with a carbon dioxide removal device 116, and the carbon dioxide removal device 116 may be provided with an exhaust gas discharge pipe 1161 for discharging the exhaust gas.

In addition, the second circulation pipe 1125 between the carbon dioxide removal unit 116 and the final flow reduction path 1121 may be provided with a heater 117 for raising the temperature of the circulating gas.

By providing the carbon dioxide removal unit 116 in the second circulation pipe 1125 as described above, the exhaust gas discharged from the second flow reduction reactor facility is supplied to the final flow reduction reactor after carbon dioxide is removed and recycled as reducing gas. In addition, by providing the heater 117 as described above, the temperature of the circulating gas can be controlled.

In addition, in another preferred embodiment of the present invention, a dedusting device, preferably wet, in a reducing gas connecting pipe, ie, an exhaust gas path, connecting the first flow reducing reactor facility 111 and the second flow reducing reactor facility 112. It is more preferable to provide a vibration damper (not shown) so that dust, sulfur, and other impurities of the exhaust gas can be removed (vibrated).

The steelmaking step after the above-mentioned steelmaking step may be carried out by a steelmaking apparatus including a refining facility such as a converter or an electric furnace.

The converter is a device for converting oxygen into molten steel by supplying oxygen or an oxygen-containing gas into the furnace to burn the carbon in the molten iron to convert the molten iron into the molten steel at the carbon saturation level. The carbon or other oxidizing component is converted into molten steel by the combustion heat, Is also a device for simultaneously raising temperature.

There are various kinds of converters, but they are all usable in the present invention. That is, the present invention can be used in the present invention regardless of the difference in the manner of cigarettes, such as the outcrossing, the low-odor or the upside-down combination, and the different styles depending on the design method of each steelmaker.

However, since the main raw material supplied in the steelmaking step contains not only hot molten iron but also massively reduced iron, it is more preferable to use a method with higher thermal efficiency, and in a preferred embodiment of the present invention, the steelmaking apparatus is as follows. It is more preferable to include the converter of.

That is, in a more preferred example of the present invention, the converter 20 is formed of molten steel using the molten iron produced in the iron making apparatus 10 as described above and the massively reduced reduced iron agglomerated in the second bulking apparatus 14 as the main raw materials. As configured, the upper and lower portions of the converter 20 are provided with a lance 21 and a nozzle 22, respectively. Oxygen is blown into the nozzle provided in the lower portion of the converter to perform the role of refining molten steel. At this time, fuel which can act as a heat source together with oxygen can be blown. The fuel may include coal, combustible gas, etc., but is not necessarily limited thereto. In addition, the fuel may be blown together with oxygen, or may be blown by a carrier gas such as nitrogen to a separate nozzle. In the lower part of the converter, in addition to the fuel, it is possible to control the base of slag such as quicklime and the like, which may act as a nucleus for decarburization, and may be blown with oxygen or by a separate carrier gas.

In addition, the lance 21 may inject a gas containing oxygen, preferably air into the furnace. The oxygen-containing gas injected into the furnace serves to additionally supply heat to the molten steel by post combustion of carbon monoxide produced by the decarburization reaction of the molten steel. At this time, a heating means may be added to the supply path of the oxygen-containing gas in order to further increase the thermal efficiency of the oxygen-containing gas, as the heating means may be any one that is commonly used, more preferably discharged from the converter A heat exchanger type heating device 211 for exchanging heat of waste gas may be used.

The converter 20 and the second block device 14 may be connected in a block-shaped reduced iron communication relationship through the block-shaped reduced iron transfer pipe 23, which can be moved. In this way, the converter 20 and the second blocker 14 are connected in a block of reduced iron transfer via a block of reduced iron transfer tube 23 to prevent oxidation of the reduced block of reduced iron. The mass reduction reduced iron transfer pipe 23 can maintain a nitrogen gas atmosphere. The converter may have a method of blowing oxygen through the nozzle 22 at the bottom as described above, but may also refine the molten steel by blowing oxygen through the above-described lance 21 or a separate lance (not shown). Has already been revealed earlier.

Another example of the integrated steelmaking system of the present invention is shown in FIGS. 5 and 6.

The integrated steelmaking system 2 shown in FIG. 5 is the integrated steelmaking system shown in FIG. 4 except that the first flow reduction and returning equipment 111 includes three flow reducing and returning paths 1111, 1112 and 1113. It is substantially the same as (1).

The integrated steelmaking system 2 shown in FIG. 6 is substantially the same as the integrated steelmaking system 1 shown in FIG. 4 except that an electric furnace 20-1 is used instead of the converter 20 as the steelmaking apparatus. Do. In addition, the number of melt reduction furnaces described in the integrated steelmaking system 2 shown in FIG. 6 may be changed to be the same as in FIG. 5.

In another preferred embodiment of the present invention, a slab casting apparatus for casting molten steel produced in the steelmaking apparatus behind the steelmaking apparatus as viewed in the molten steel flow direction may be arranged. At this time, in order to more compact equipment configuration, the slab casting apparatus preferably includes a continuous casting machine and a rolling device, it is preferable that the continuous casting machine and the rolling device are directly connected to each other. In the present invention, the direct connection means that the slab discharge portion of the casting portion and the slab inlet of the rolling apparatus are the same and are substantially spatially connected.

7 to 12 illustrate a system in which the slab casting device 30 is included in the integrated steelmaking system, which is a preferred embodiment of the present invention of FIGS. 1 to 6, respectively. As can be seen from the drawing, the slab casting apparatus 30 casts the slab by continuous casting in the continuous casting machine 31 and discharges the molten steel produced in the converter 20 or the electric furnace 20-1. If the thickness of the slab is too thick, the rolling burden of the rolling apparatus increases. Therefore, in order to immediately roll the slab cast in the continuous casting machine 31, the slab produced in the continuous casting machine 31 has a thickness of 30 to 150 mm desirable. More preferable thickness is 120 mm or less, most preferably 100 mm or less. As an example of a more preferable method for this, the thickness of the slab discharged from the mold 313 of the continuous casting machine 31 is preferably 40 ~ 200mm, then liquid core reduction (liquid core reduction) located before the discharge of the continuous casting machine 31 Up to 30% liquid phase reduction may be performed in region 314. When the thickness is satisfied, the liquid pressure may not be applied.

The slab discharged from the continuous casting machine (31) is rolled by the rolling device (32). A slab cutting device 315 may be included between the continuous casting machine and the rolling device to ensure continuity between the continuous casting machine 31 and the rolling machine 32, which may have different processing speeds.

The rolling device is divided into a rough rolling mill 322 and the finishing mill 326 to roll to produce a steel sheet. Heating means 324 may be added between the roughing mill 322 and the finishing mill 326. The heating means 324 may be an induction furnace, a tunnel furnace, or the like, and the induction furnace system is preferable for a more compact facility configuration. Further, it is more preferable that the slab discharging means 323 is provided at one or more of the front and rear of the heating means (the shape provided in front of the figure). The slab discharging means 323 discharges the slab in the vertical direction (lateral direction) of the slab advancing direction, and discharges the slab, which can not be processed, from the production line when an operation failure occurs in the previous and subsequent processes . It is preferable that the length of the slab discharging means corresponds to the length of one to two slabs (for example, 5.5 to 11 m).

The rough rolled and heated slab is then reduced to the desired thickness through finishing rolling to become the final product. At this time, the thickness of the product and the demand may be wound in the form of a coil according to the demand. The finishing mill 326 is preferably composed of 3 to 8 rolling mills, and more preferably 4 to 7 rolling mills. There may further be a cooling device 328 at the end of the finishing mill.

In addition, a coil box 325 may be further included at the front of the finishing mill 326, preferably at the rear of the heating unit 324, to wind and store the roughly rolled steel sheet. The coil box 325 may serve as a buffer for resolving inconsistency in the processing speed between the rough mill 322 and the finishing mill 326, to uniform the temperature in the steel sheet, or to secure a time margin in the process. At this time, it is more preferable that the coil box 325 is insulated. During continuous continuous rolling, the steel plate may not pass through the coil box 325. It is preferable that the scale removing device 321 is disposed in front of at least one of the roughing mill 322 and the finishing mill 326 so that rolling is performed on the surface of the steel plate with the scale removed, Do. A cutter 327 is located behind the finishing mill to cut the product to a desired size. A preferred example of the cutter 327 is a shearing machine.

In the present invention, the self-structure of each of the fluidized-bed reactors, the agglomerating device and the melting furnace is not particularly limited, and any of them can be used as long as it is commonly used.

As used herein, the terms " first " and " second " do not mean a sequence, but merely used to distinguish members.

The term " initial " and " final ", as used herein, are defined based on the direction of movement of the minute iron ore. For example, the first and second fluidized-bed reactors, And the supplied fluidized-bed reactor is referred to as a final-fluidized-bed reactor.

In addition, as an apparatus for converting molten iron into molten steel in the steelmaking step of the present invention has been described by way of example, it is necessary to note that an electric furnace may be used. Further, in the steelmaking step described above, an additional secondary refining process may be further included after the converting process. The secondary refining process is a process of controlling the components of the molten steel discharged from the converter or electric furnace to be suitable for the final product and controlling the temperature of the molten steel to be suitable for casting. The bubbling facility, the vacuum refining facility, The present invention is not limited thereto since it may further include any process as long as it is a secondary refining process used in the technical field to which the present invention belongs. That is, in one preferred embodiment of the present invention, the steelmaking step may further include a secondary refining facility subsequent to the converter.

In addition, in the steelmaking step, at least one of a desulfurizer, a talliner, and a desulfurization talliner to desulfurize or degas the molten iron produced in the melting furnace between the converter and the melting furnace to convert the desulfurized and / or talline- It can also be put into an electric furnace. Other pretreatment processes that can be carried out before a converter or furnace process, so-called primary refining in the field of steel, may all be included in the present invention. Accordingly, it is noted that the steelmaking apparatus of the present invention is a systematic concept that can include both a converter or an electric furnace, as well as a hot metal pretreatment device and a secondary refining device that can be disposed before or after the hot metal pretreatment device have. Of course, these devices are not necessarily included.

Hereinafter, another embodiment of the integrated steelmaking method of the present invention will be described with reference to FIG. 1.

As shown in FIG. 1, one preferred embodiment of the present invention includes a reduced iron ore manufacturing apparatus 11 having a first flow reduction reactor facility 111, a first bulking apparatus 13, and a melting furnace 12. A wire making apparatus 10; And molten steel is manufactured using the steelmaking apparatus 1 containing the converter 20.

In the present invention, reduced iron ore is reduced by producing the reduced iron ore in the first flow reduction facility (111), respectively.

That is, the iron ore or the like is charged into the fluidized-bed reactor, and the charged iron ores are reduced while forming the gas fluidized bed by the reducing gas introduced into the gas supply pipe to produce the reduced iron ore. The iron ores to be charged have a sufficiently large specific surface area so that the reduction is easy and the particle size is not too large so as to be flowed by the fluidizing gas. In this invention, it is preferable that it is 12 mm or less, It is more preferable that it is 10 mm or less, It is most preferable that it is 8 mm or less.

In the first flow reduction reactor (111), it is preferable that the reduction of iron ore is performed so that the reduction rate is 50 to 80%. This is in the preferred embodiment of the present invention, reducing the iron ore using the reducing gas discharged from the melting furnace 12, the reducing gas discharged from the melting furnace 12 (also called 'FOG') is dust or sulfur content If the high reduction rate of the iron ore is high, there is a problem that the sticking phenomenon occurs in the interior, because the additional reduction can be made in the melting furnace. However, when the reducing gas is supplied by the hydrogen-based reducing gas supply facility 151 as described below, the reduction rate may be higher, and in some cases, may be 80 to 95%.

As described above, the reduced iron ore reduced in the first flow reduction facility (111) is supplied to the first blocker 13, and then agglomerated to produce block iron. The method of producing the agglomerated reduced iron by the agglomerating device 13 is a method already known in the technical field of the present invention, for example, Korean Patent Laid-Open Nos. 10-2005-0068319, 10-2003-0085795 , And various other techniques in the technical field of the present invention can be used in addition to the above.

Thereafter, the mass reduced reduced iron, which is agglomerated in the first mass converter 13, is supplied to the melting furnace 12 to melt to prepare molten iron.

It is preferable that the mass reduction reduced iron massified by the said 1st mass converter 13 is charged to a melting furnace in the high temperature state of 500-800 degreeC. The molten reduced iron can be further reduced by charging a reducing agent for reducing the agglomerated reduced iron to the melting furnace 12. As the reducing agent, a carbon-based reducing agent may be used, and among these, a coal-based reducing agent such as molded charcoal, algae, coke or the like is more preferably used.

As described above, the molten iron produced in the melting furnace 12 is supplied to the converter 20 to manufacture molten steel. In some cases, other raw materials such as scrap may be charged together with the molten iron. The molten iron may be passed through one or more of the desulfurization, talline, or simultaneous desulfurization talline processes prior to feeding to the converter 20, or may be through other pretreatment processes.

In addition, the bulk reduction iron produced in the first flow reduction reactor (111) does not necessarily need to be introduced into the melting furnace, and some may be directly introduced into the steelmaking apparatus.

In the integrated steelmaking method, the hydrogen-based reducing gas supply facility 15 supplies all or part of the reducing gas required by the first flow reduction and reactor facility 111.

In the first flow reduction reactor (111) it is possible to circulate the discharged exhaust gas to the reducing gas. At this time, the circulated exhaust gas after the at least one of the step of removing the carbon dioxide by the carbon dioxide removal device 118 and the temperature control by a heater (not shown) after the first flow reduction reactor ( It is preferred to be supplied to 111.

When the molten steel is manufactured in the converter 20, it is preferable to supply fuel and oxygen (O ₂ ) from the bottom of the converter 20 to heat the molten steel. In addition, particles of a material such as quicklime may be blown together to control the basicity of slag and serve as a nucleus for decarburization.

In addition, when the molten steel is manufactured in the converter 20, it is preferable to inject the gas containing oxygen from the upper part of the converter 20, preferably air, into the furnace for secondary combustion of carbon monoxide in the furnace. Further, in order to further increase the thermal efficiency of the oxygen-containing gas, the oxygen-containing gas is more preferably heated and injected. As a more preferable method for this, it is possible to heat the oxygen-containing gas by heat-exchanging the heat of the waste gas discharged from the converter.

In the aforementioned steelmaking step, after the converter process, an additional secondary refining process may be further included. The secondary refining process may be any secondary refining process used in the art to which the present invention belongs, so that it is not particularly limited in the present invention. That is, in one preferred embodiment of the present invention, the steelmaking step may further include a secondary refining step subsequent to the converter.

Hereinafter, another embodiment of the integrated steelmaking method of the present invention will be described with reference to FIG. 4.

As shown in FIG. 4, in one preferred embodiment of the present invention, a reduced iron ore manufacturing apparatus 11 having a first flow reduction reactor facility 111 and a second flow reduction reactor facility 112 and a first bulking device are provided. (13), an iron making apparatus (10) including a second bulking apparatus (14) and a melting furnace (12); And molten steel is manufactured using the steelmaking apparatus 1 containing the converter 20.

In the present invention, reduced iron ore is reduced in the first flow reduction reactor (111) and the second flow reduction reactor (112), respectively.

That is, the iron ore or the like is charged into the fluidized-bed reactor, and the charged iron ores are reduced while forming the gas fluidized bed by the reducing gas introduced into the gas supply pipe to produce the reduced iron ore. The iron ores to be charged have a sufficiently large specific surface area so that the reduction is easy and the particle size is not too large so as to be flowed by the fluidizing gas. In this invention, it is preferable that it is 12 mm or less, It is more preferable that it is 10 mm or less, It is most preferable that it is 8 mm or less.

In the first flow reduction reactor (111), it is preferable that the reduction of iron ore is performed so that the reduction rate is 50 to 80%. This is in the preferred embodiment of the present invention, reducing the iron ore using the reducing gas discharged from the melting furnace 12, the reducing gas discharged from the melting furnace 12 (also called 'FOG') is dust or sulfur content If the high reduction rate of the iron ore is high, there is a problem that the sticking phenomenon occurs in the interior, because the additional reduction can be made in the melting furnace. If, when the hydrogen-based reducing gas is supplied to the first flow reduction reactor (111), the reduction rate may be high, in some cases, may reach 80 to 95%. In addition, it is preferable that the reduction of iron ore in the second flow reduction reactor is performed so that the reduction rate is 80 to 95%. This is, in another preferred embodiment of the present invention, as a reducing gas used in the first flow reduction reactor (111) or the second flow reduction reactor (112) or exhaust gas of the first flow reduction reactor (111) or the like. Hydrogen-based reducing gas is used through a separate supply line, because at this time, dust or sulfur is purified, or since the dust or sulfur is supplied from the beginning, the risk of the above-described problems may be reduced.

As described above, the reduced iron ore reduced in the first flow reduction reactor facility 111 and the second flow reduction reactor facility 112 is respectively provided to the first blockage device 13 and the second blockage device 14. Agglomerated reduced iron is produced by agglomeration by supplying. The method for manufacturing the iron reduction reduced by the massing device (13, 14) is a method already known in the art to which the present invention belongs, for example, Korean Patent Publication No. 10-2005-0068319, 10-2003 The method of manufacturing a block reduced iron using the apparatus of -0085795 is mentioned, In addition, various techniques in the technical field of this invention can be used.

Thereafter, the mass reduced reduced iron, which is agglomerated in the first mass converter 13, is supplied to the melting furnace 12 to melt to prepare molten iron.

It is preferable that the mass reduction reduced iron massified by the said 1st blocker 13 and the said 2nd blocker 14 is loaded in a melting furnace or steelmaking apparatus in the high temperature state of 500-800 degreeC. The molten reduced iron can be further reduced by charging a reducing agent for reducing the agglomerated reduced iron to the melting furnace 12. As the reducing agent, a carbon-based reducing agent may be used, and among these, a coal-based reducing agent such as molded charcoal, algae, coke or the like is more preferably used.

As described above, the molten iron produced in the melting furnace 12 and the block reduced iron masses agglomerated in the second block 14 are supplied to the converter 20 to manufacture molten steel. The molten iron may be passed through one or more of the desulfurization, talline, or simultaneous desulfurization talline processes prior to feeding to the converter 20, or may be through other pretreatment processes.

For efficient converter operation, the molten iron and the bulk reducing iron supplied to the converter are preferably charged at a charge of 40 to 80% by weight molten iron and 20 to 60% by weight of the bulk reducing iron.

In FIG. 4, the molten iron was manufactured by using agglomerated reduced iron ore manufactured in the first flow reduction reactor facility 111, but it was manufactured by agglomerating reduced iron ore manufactured in the second flow reduction reactor facility 112. It will be appreciated that it can be manufactured using. In addition, the bulk reduction iron produced in the first flow reduction reactor (111) does not necessarily need to be all put into the melting furnace, and some may be directly put into the steel making apparatus, which is in the second flow reduction reactor (112) It is the same as that the manufactured bulk reducing iron can be introduced into the melting furnace without the need of directly feeding into the steelmaking apparatus. If there is a failure in one of the flow reduction furnace equipment (111,112), the process may be carried out by sending some or all of the iron oxide produced in the other one to the melting furnace.

In the integrated steelmaking method, the hydrogen-based reducing gas supply facility 15 supplies all or part of the reducing gas required by the first flow reduction reactor facility 111 or the second flow reduction reactor facility 112. If additional gas other than the reducing gas supplied from the hydrogen-based reducing gas supply facility 15 is required in the second flow reduction reactor facility 112, according to another preferred aspect of the present invention, the first flow reduction reactor facility The exhaust gas of 111 can be used as additional reducing gas. In this case, the exhaust gas discharged from the first flow reduction reactor (111) is supplied to the second flow reduction reactor (112) through the reducing gas connection pipe 1116 and used as a part of reducing gas, and Supplying the hydrogen-based reducing gas supplied from the hydrogen-based reducing gas supply facility 15 to the second flow reducing reactor facility 112 through the hydrogen-based reducing gas connecting pipe 151 to use as another part of the reducing gas. desirable.

In at least one of the first flow reduction reactor (111) and the second flow reduction reactor (112), the discharged exhaust gas may be circulated to the reducing gas. At this time, the circulated exhaust gas is at least one of the step of removing the carbon dioxide by the carbon dioxide removal device (116,118) and the temperature control by the heater (117, the heater of the first flow-reduction facility side is not shown). After the step, it is preferable to be supplied to the at least one flow reduction reactor (111, 112) or the other one (112, 111).

When the molten steel is manufactured in the converter 20, it is preferable to supply fuel and oxygen (O ₂ ) from the bottom of the converter 20 to heat the molten steel. In addition, particles of a material such as quicklime may be blown together to control the basicity of slag and serve as a nucleus for decarburization.

In addition, when the molten steel is manufactured in the converter 20, it is preferable to inject the gas containing oxygen from the upper part of the converter 20, preferably air, into the furnace for secondary combustion of carbon monoxide in the furnace. Further, in order to further increase the thermal efficiency of the oxygen-containing gas, the oxygen-containing gas is more preferably heated and injected. As a more preferable method for this, it is possible to heat the oxygen-containing gas by heat-exchanging the heat of the waste gas discharged from the converter.

In the aforementioned steelmaking step, after the converter process, an additional secondary refining process may be further included. The secondary refining process may be any secondary refining process used in the art to which the present invention belongs, so that it is not particularly limited in the present invention. That is, in one preferred embodiment of the present invention, the steelmaking step may further include a secondary refining step subsequent to the converter.

In a further preferred embodiment of the integrated steel making method of the present invention, subsequent to the steelmaking step, a slab casting may follow. At this time, it is preferable that the slab casting step is performed by a slab casting step including a continuous casting step and a rolling step, and the continuous casting step and the rolling step are preferably directly connected to each other for a more compact equipment configuration.

The invention will be described through a system further comprising the slab casting apparatus illustrated in FIGS. 7 to 12. As can be seen in the drawing, the slab is cast and discharged in a continuous casting process in a continuous casting process. If the thickness of the slab is too thick, the rolling burden of the rolling apparatus 32 increases. Therefore, in order to immediately roll the slab cast in the continuous casting step, it is preferable that the slabs produced in the continuous casting step have a thickness of 30 to 150 mm Do. More preferable thickness is 120 mm or less, most preferably 100 mm or less. As an example of a more preferable method for this, the thickness of the slab discharged from the continuous casting machine 31 mold 313 used in the continuous casting step is preferably 40 ~ 200mm, and then the liquid pressure drop (before the continuous casting step discharge) 25% or less of liquid reduction can be performed in a liquid core reduction) region. When the thickness is satisfied, the liquid pressure may not be applied. In addition, the casting speed in the continuous casting step is preferably 4.5mpm ~ 15mpm.

The slab discharged from the continuous casting step is rolled by a subsequent rolling step. At this time, the slab may be cut and fed to the rolling step after the continuous casting step to ensure continuity between the continuous casting step and the rolling step, which may have different processing speeds.

The rolling step is divided into rough rolling step and finishing rolling step to roll the slab to produce a steel sheet. In order to secure the temperature required in the finishing rolling step, a heating step may be added between the rough rolling step and the finishing rolling step. The heating means used in the heating step may be an induction furnace, a tunnel furnace, or the like, and the induction heating furnace is preferable for a more compact facility configuration. Further, in an emergency, the slab discharging step may be further included before or after the heating means.

The rough and heated slab is then pressed to the desired thickness through the finishing rolling step to become the final product. At this time, the thickness of the product and the demand may be wound in the form of a coil according to the demand. After the finish rolling step, a cooling step may be further included.

In addition, before the finishing rolling step, a storage step of winding the rough rolled steel sheet and storing the coil box 325 may be further included. The coil box may serve as a buffer for resolving inconsistency in processing speed between the rough mill 322 and the finishing mill 326, to uniform the temperature in the steel sheet, or to secure a time margin in the process. The thickness of the steel sheet wound on the coil box is more preferably 20 mm or less. At the time of continuous continuous rolling, the steel sheet may not include the storing step. In addition, it is more preferable for the steel sheet or the roll protection to carry out the rolling with the scale removed on the surface of the steel sheet after the descaling step is placed before at least one of the rough rolling step and the finishing rolling step. The cutting stage is located behind the finishing mill to cut the product to a desired size. The cutting step may be performed before or after the cooling step.

As described above, the integrated steelmaking system of the present invention can produce not only molten iron but also agglomerated reduced iron at the same time in one iron making apparatus, so that the amount of molten iron that can be supplied by one unit is one large blast furnace. For example, it may have a productivity high enough to be comparable to a blast furnace capable of producing a molten iron of 3 million tons or more, preferably 4 million tons or more.

In other words, the molten iron produced through the melting furnace is produced in an amount of 1.3 to 2.5 million tons per year, and similarly, the bulk reducing iron, which is directly injected into the converter from the bulking apparatus, can also be produced in an amount of 1.3 to 2.5 million tons per year. Product mixes have high productivity comparable to large blast furnaces.

In addition, according to a preferred aspect of the steelmaking apparatus, by maximizing the thermal efficiency in the converter can be operated under a low molten iron ratio (HMR) compared to the conventional has the effect that can be flexibly managed in the molten steel manufacturing environment.

1,2: Integrated Steelmaking System
10: Welding machine
11: Reduced iron ore production equipment
111: first flow return reactor
112: second flow reduction reactor
1111,1112,1113,1114,1121,1122,1123,1124
1115: first circulation tube
1125: second circulation tube
116: carbon dioxide removal unit
1161: exhaust gas discharge pipe
117: burner
12: Melting furnace
121: gas supply pipe
13: first blocker
131: Hopper 1
132: first reduced iron supply pipe
14: second block device
141: Hopper 2
142: second reduced iron supply pipe
20: Converter
20-1: Electric furnace
21: Lance
211: heating device
22: Nozzle
23: Mass reduction reduced iron transfer pipe
30: Slab casting device
31: Continuous casting machine
311:
312: Turn Dish
313: Mold
314: Liquid pressure reduction area
315: Slab cutting device
32: Rolling device
321: Scale removal device
322: rough rolling mill
323: slab discharge means
324: Heating means
325: Coil box
326: Finishing mill
327: Cutter
328: Cooling unit
329: Coil

Claims (34)

A reduced iron ore manufacturing apparatus comprising a first flow reduction reactor facility configured to reduce the iron ore including one or more flow reduction furnaces to produce reduced iron ore;
A hydrogen reducing gas supply facility connected to the first flow reducing reactor facility in a gas communication relationship to supply hydrogen reducing gas;
A first bulking device configured to produce a bulky reducing iron by agglomerating and receiving the reduced iron ore from the first flow reduction facility; And
A steelmaking apparatus including a melting furnace for melting molten iron reduced in mass in the first massaging apparatus to produce molten iron;
Consolidated steel making system comprising a steel making device for receiving molten steel produced in the steel making equipment to manufacture molten steel. A reduced iron ore manufacturing apparatus including a first flow reduction reactor facility and a second flow reduction reactor facility, each configured to reduce the iron ore including one or more flow reduction reactors to produce reduced iron ore;
A hydrogen-based reducing gas supply facility connected to the first flow-reduction facility or the second flow-reduction facility in a gas communication relationship to supply hydrogen-based reducing gas;
A first bulking device and a second bulking device configured to produce the bulk reducing iron by receiving and bulking the reduced iron ore from the first and second flow reducing facility; And
A steelmaking apparatus including a melting furnace for melting molten iron reduced in mass in the first massaging apparatus to produce molten iron;
Consolidated steelmaking system comprising a steelmaking apparatus for receiving molten iron and a mass reduction reduced iron produced in the iron making apparatus to produce molten steel. According to claim 1 or 2, wherein the final flow path and the melting furnace of the first flow reduction reactor is connected in a gas communication relationship through a gas supply pipe, the first flow path and the first flow reduction path of the first flow reduction facility The final flow return path of the second flow return path facility is an integrated steelmaking system connected in a gas communication relationship through a reducing gas connection pipe. According to claim 1 or claim 2, wherein at least one of the first flow-reduction reactor facility and the second flow-reduction reactor facility comprises a circulation pipe and the initial flow reduction path of the at least one facility to the circulation pipe. And an integrated steelworks system connected in a gas communication relationship to a final flow return path of the at least one facility. [5] The flow path of the first flow reduction reactor and the melting furnace are connected to each other in a gas communication relationship through a gas supply pipe, and the flow path and the second flow reduction path of the first flow reduction facility. The flow reduction path of the facility is connected in a gas communication relationship through a reducing gas connecting pipe, the reducing gas connecting pipe is connected to the circulation pipe of the at least one equipment integrated steelmaking system. The integrated steelmaking system according to claim 1 or 2, wherein three or four flow reduction paths of the first flow reduction path facility and four flow reduction paths of the second flow reduction path facility. The integrated steelmaking system according to claim 4, wherein at least one of the circulation pipes is provided with at least one of a carbon dioxide removal device and a heater. The integrated steelmaking system according to claim 5, wherein at least one of the circulation pipes is provided with at least one of a carbon dioxide removal device and a heater. 3. The integrated steelmaking system according to claim 1 or 2, wherein the exhaust gas of the first flow reduction reactor is supplied to the second flow reduction reactor through a reducing gas connecting pipe. 10. The integrated steelmaking system according to claim 9, wherein the reducing gas connecting pipe is further provided with a wet damping device. The steelmaking apparatus of claim 1 or 2, wherein the steelmaking apparatus includes a converter or an electric furnace, wherein the converter or the electric furnace and the second bulkhead are connected to the bulk reducing iron through a bulk reducing iron transfer pipe through which the bulk reducing iron is movable. Connected integrated steelmaking system. The integrated steelmaking system according to claim 11, wherein a bottom of the converter is provided with a nozzle configured to supply fuel and oxygen (O ₂ ), and a lance for supplying an oxygen-containing gas is provided at the top of the converter. 13. The integrated steelmaking system of claim 12, wherein the oxygen containing gas is heated air. The integrated steelmaking system according to claim 1 or 2, further comprising a slab casting apparatus in which a continuous casting machine for casting molten steel manufactured in the steelmaking apparatus and a rolling apparatus are directly connected. 15. The integrated steelmaking system according to claim 14, wherein the continuous casting machine manufactures slabs having a thickness of 30 to 150 mm. The integrated steelmaking system according to claim 15, wherein the circumferential speed of the continuous casting machine is 4 to 15mpm. The integrated steelmaking system according to claim 14, wherein the rolling apparatus includes a rough rolling mill and a finishing mill, and further comprising a steel plate heating means between the rough rolling mill and the finishing mill. 18. The integrated steelmaking system according to claim 17, further comprising a coil box between the steel sheet heating means and the finishing mill to wind and store the steel sheet in a coil state. In the first flow reduction reactor, reducing iron ore, respectively, to produce reduced iron ore, wherein the first flow reduction facility using a hydrogen-based reducing gas as part or all of the reducing gas;
In the first block device, the step of receiving the powdered iron ore reduced in the first flow reduction facility to agglomerated to produce a bulk reducing iron; And
In the smelting furnace, the steelmaking step comprising a molten iron manufacturing step of manufacturing the molten iron by melting the mass of the reduced iron mass in the first mass converter;
Consolidated steelmaking method comprising the step of manufacturing molten steel by receiving the molten iron prepared in the steelmaking step. Reducing the iron ore in the first flow reduction reactor facility and the second flow reduction reactor facility, respectively, to produce reduced iron ore, in the first flow reduction facility or the second flow reduction facility, all or less of the reducing gas Using hydrogen-based reducing gas as part;
In the first block and the second block, the first flow reducing facility and the second flow reducing facility is reduced by receiving the iron ore reduced by the step of producing the mass reduction iron; And
In the smelting furnace, the steelmaking step comprising a molten iron manufacturing step of manufacturing the molten iron by melting the mass of the reduced iron mass in the first mass converter;
Consolidated steelmaking method comprising the step of manufacturing molten steel by receiving the molten iron and block reduced iron produced in the steelmaking step. 21. The method according to claim 19 or 20, wherein the reduction of the iron ore in the first flow reduction reactor facility is carried out so that the reduction rate is 50 to 80%, and the reduction rate of the iron ore in the second flow reduction reactor facility is 80 to 95. Integrated steel making method to be%. 21. The method of claim 19 or 20, wherein the molten iron and the bulk reducing iron supplied to the steelmaking step are charged at a charge ratio of 40 to 80 wt% of the molten iron and 20 to 60 wt% of the bulk reducing iron. 21. The method of claim 19 or 20, wherein the steelmaking step is performed by a converter or an electric furnace. 21. The method of claim 19 or 20, wherein the exhaust gas discharged from the first flow reduction reactor is supplied to the second flow reduction reactor and used as the remaining portion of the reducing gas. 25. The method of claim 24, further comprising the step of removing the exhaust gas discharged from the first flow reduction reactor. 21. The exhaust gas according to claim 19 or 20, wherein the exhaust gas discharged from at least one of the first and second flow reduction reactors is circulated to a reducing gas, and the circulated gas is discharged by a carbon dioxide removal device. The process of one of the steps of removing and adjusting the temperature by a heater, and then supplying the at least one facility or the other facility. 21. The method of claim 19 or 20, wherein the bulk reducing iron is charged to a melting furnace or a steelmaking step at a high temperature of 500 ~ 800 ℃. 21. The integrated steelmaking method according to claim 19 or 20, wherein when there is a failure in the first flow reduction reactor, a molten iron is manufactured by supplying some or all of the bulk reducing iron produced in the second flow reduction reactor to the melting furnace. 21. The integrated steelmaking method according to claim 19 or 20, wherein when producing molten steel in the converter, fuel and oxygen (O ₂ ) are supplied at the bottom of the converter, and a heated oxygen-containing gas is supplied at the top of the converter. 30. The method of claim 29, wherein the oxygen containing gas is heated air. 21. The method of claim 19 or 20, further comprising a slab casting step in which a continuous casting step of casting molten steel manufactured in the steelmaking step and a rolling step are directly connected. 32. The method of claim 31, wherein the continuous casting machine manufactures slabs having a thickness of 30 to 150 mm. 32. The method of claim 31, wherein the rolling step includes a rough rolling step and a finishing rolling step, and a steel sheet heating step is further included between the rough rolling step and the finishing rolling step. 34. The method of claim 33, further comprising a storage step of winding and storing the steel sheet in a coil state between the steel sheet heating step and the finishing rolling step.

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