KR101607254B1 - Combiner Ironmaking facilities - Google Patents

Abstract

The present invention provides a complex iron manufacturing apparatus. According to the present invention, an iron manufacturing apparatus based on a flow reducing furnace and a coal-fillable melting gas brazier and an iron manufacturing apparatus based on a melting bath-type melting reducing furnace are joined by a separate flow reducing furnace additionally arranged as a medium. The iron manufacturing apparatus based on the flow reducing furnace and the coal-fillable melting gas brazier uses conventional gas and raw materials for metallurgy to stably produce iron, and the iron manufacturing apparatus based on the melting bath-type melting reducing furnace and connected to the iron manufacturing apparatus based on the flow reducing furnace and the coal-fillable melting gas brazier uses low quality gas and raw materials unsuitable for conventional metallurgy to stably produce iron.

Description

[0001] Combination Ironmaking facilities [

The present invention relates to an apparatus for manufacturing a composite molten iron, and more particularly, to a method for manufacturing molten iron by directly using iron-containing ores in powdered or bulk form, And a reactor for performing a reduction and dissolution of a plurality of iron-containing materials having a shape and function.

Currently, about 60% of the world's iron production is produced from the blast furnace, which was developed from the 14th century. The blast furnace method is a method in which molten iron is produced by introducing iron ores and sintered cokes, which have been sintered, into a blast furnace and blowing oxygen to reduce iron ore to iron.

As described above, the blast furnace method, which is a type of the molten iron production apparatus, requires raw materials having a particle size capable of securing a certain level of strength or more and ensuring air permeability in the furnace. Therefore, The carbon source used depends on the coke treated with a specific coking coal, and the iron source mainly depends on the sintered ores that have undergone a series of agglomeration processes.

Accordingly, since the present blast furnace method necessarily involves raw material pre-treatment facilities such as coke production facilities and sintering facilities, it is necessary not only to construct additional facilities other than the blast furnace, but also to make various environmental pollutants There is a problem that the investment cost is consumed in a large amount due to the necessity of installation of the environmental pollution prevention equipment for Korea, and the manufacturing cost is rapidly increased.

In order to solve the problems of the blast furnace method, steel mills in the world have used general coal directly as a fuel and reducing agent, and as a steel source, they use a spectroscope that occupies more than 80% We are making a lot of efforts to develop the seasonal law.

European Patent Publication No. 1,689,892 discloses an apparatus for manufacturing molten iron directly using iron-containing ores in powdered or granular coal and pulverized coal, and a method for producing molten iron.

In the above-mentioned European patent, a molten iron manufacturing apparatus for directly using iron-containing ores in powdered or bulk form of general coal and powder is characterized by comprising a multi-stage fluidized-bed reactor for reducing and burning iron- ; A high temperature compacting device for compacting the reduced iron discharged from the fluidized-bed reactor to produce a high-temperature compacted compact; The coal and the massive general coal produced by bulking from the general coal of powder is continuously supplied to form a coal filler layer of a certain height inside the coal filler layer, and through the plurality of tuyere formed at the bottom of the outer wall of the coal filler layer, oxygen And the pulverized coal is blown by the oxygen, the pulverized coal and the coarse coal in the coal-packed bed are burned by the oxygen, and the hot gas formed by the burning rises in the packed bed and is produced in the hot compacting apparatus as sensible heat, The hot-rolled compacted irons descending in the coal-filled layer after being charged to the top of the coal-filled layer, and the sub-materials charged into the upper portion of the coal-packed bed together with the hot-rolled compacted material are heated, melted and slagged to manufacture molten iron and slag The molten iron and slag are periodically discharged to the outside after being accumulated under the coal filling layer, A melting gasification furnace for discharging a high temperature gas passed through the molten coal filling layer and supplying it as a reducing gas for reducing iron ore containing ore in the multistage fluidized-bed reactors; And the like.

In addition, the gas discharged to the multi-stage fluidized-bed reactor is cooled through a collecting device, and then a part of the gas is branched and compressed to remove CO ₂ , and then mixed with a high-temperature reducing gas discharged from the melter- The exhaust gas reforming circulation device is provided so as to additionally supply a reducing gas to the reducing furnace. In the exhaust gas reforming circulation device, the CO ₂ -removed gas corresponds to the lowermost part of the multi-stage flow reducing furnace, Is supplied to the upstream end of the final fluidized-bed reduction reactor.

In the molten steel manufacturing process, 60 to 70% of the reduction of iron ore is progressed by the indirect reduction by the reducing gas supplied from the melt gasification in the multistage fluidized-bed reduction reactor, and the remainder of 30 to 40% And the coal is heated in the coal gasification furnace so that the carbon content of the coal in the coal gasification furnace can be reduced by indirect reduction by the coal combustion gas rising in the coal gasification bed in the coal gasification furnace, And direct reduction by coal combustion gas.

Therefore, it is important to smoothly contact the hot coal combustion gas in the reducing gas / iron ores and the melter-gasifier in the fluidized-bed reactor so that the reduction of the iron ores is smoothly performed.

The gas / spectral contact in the above-mentioned flow path is considered to have no problem considering the high mixing efficiency of the fluidized-bed reduction reactor, but the contact of the gas / high-temperature reduction compacted material inside the coal- Is influenced by the gas flow distribution in the coal filling layer, and the factor determining the gas flow distribution is the air distribution in the coal filling layer.

In addition, the pore distribution in the coal-fired bed is such that molten iron and slag produced by heating, melting and slagging the hot-reduced compacted material and the subsidiary material in the coal-fired bed are passed through the coal-filled bed and discharged to the lower portion of the coal- But also serves as a decisive factor for smoothly maintaining the molten steel / slag flow.

The distribution of voids in the coal-filled layer is greatly affected by the high-temperature properties of coal forming the coal-filled layer, thereby limiting the rank of coal that can be used in the above-described molten iron manufacturing apparatus .

In addition, as described above, the molten iron and the slag must pass through the coal-filled layer in order to discharge the molten gas to the outside of the melting and gasifying furnace. Of the molten iron and slag, the amount and flowability of the slag are particularly important. The above-mentioned slag characteristic is determined by the amount and composition of gangue in the ore used as a raw material in the above-mentioned molten iron manufacturing apparatus, and the quality of the ore usable in the molten iron manufacturing apparatus is limited.

In addition, when the ore containing a large amount of phosphorus is used in accordance with the high reducing atmosphere in the coal-filled layer, there is a problem that a large amount of phosphorus component which is difficult to refine in the produced molten iron is contained, , There is a restriction on the raw ore used.

The published data on the actual operation result of the molten iron manufacturing apparatus disclosed in the above-mentioned European Patent Publication No. 1,689,892 shows that the molten iron manufacturing apparatus is operated stably and the range of available ore grade and rank of the coal is However, the grade of ore that can be used in the above-described molten iron manufacturing apparatus and the rank of coal are reported to be limited.

 On the other hand, other examples of the melt reduction method are disclosed in U.S. Patent Nos. 6332745B1, 6379422B1, and 6602321B1.

In the above-mentioned US patent, a molten iron manufacturing apparatus includes a molten iron type reactor, a molten bath type reactor composed of a slag layer formed on the molten iron layer, a gas layer formed on the slag layer, and the like; A secondary combustion lance formed from the upper portion of the molten bath type reactor to the upper portion of the slag layer and capable of blowing hot hot air with oxygen enriched above the slag layer; Type reactor and penetrates the slag layer in the molten bath-type reactor to form an upper portion of the molten iron layer below the slag layer, that is, to the boundary of the slag layer and the molten iron layer, A coal blowing lance and a coal ore receiving lance which are configured to be individually blown from the coal lance; A preliminary reducing furnace formed to preheat / preliminarily reduce the ore ore taken in the molten bath-type reactor using a part of the hot gas discharged from the molten bath-type reactor; A scrubber for cooling / cleaning gas discharged from the preliminary reducing furnace; A scrubber for cooling / cleaning the exhaust gas to the molten bath-type reactor other than the gas supplied to the preheating furnace; And a hot air furnace provided to form hot air supplied through the secondary-side lance.

In the apparatus for producing molten iron described above, the reduction of iron ore proceeds in a molten state in a molten bath formed in the molten bath type reactor, and coal for supplying the reducing agent necessary for the reduction is supplied into the molten bath, The gas generated by the reduction reaction of iron ore and coal in the molten bath is supplied as combustion generated by combustion of the oxygen-enriched air hot air supplied from the secondary combustion lance, that is, heat generated in the secondary combustion.

The use of air hot air as the combustion and oxidizing gas causes the reducing gas of the hot gas discharged from the molten bath-type reactor to be supplied to the preliminary reducing furnace to be extremely low, and the reduction of the ore that proceeds in the preliminary reducing furnace 20% or less. The above-mentioned ores and coals are pulverized to 1 mm or less so that rapid melting and reaction can proceed in the molten bath, and then they are blown. The molten iron and slag produced by the reaction are discharged continuously or periodically through separate outlets respectively.

The above-described apparatus for producing molten iron is characterized in that all the reactions and the discharge of molten iron / slag are carried out in a molten state, so that the restrictions on the quality of the coal and ore usable in comparison with the molten iron manufacturing apparatus disclosed in the above-mentioned European Patent Publication No. 1,689,892 As mentioned above, it is considered that the thermal efficiency is very high as the melting and reduction reactions proceed simultaneously and the secondary combustion is actively utilized.

However, various equipment problems and operational problems have been reported from published data on actual operation results of the molten iron manufacturing apparatus disclosed in US 6332745B1.

The problem that most affects the operation rate and the productivity in the above problems is that the connection operation of the molten bath-type reactor and the preliminary reducing furnace connected thereto is not smoothly performed. This is because the following problems occur in the molten bath- The temperature and the property of the gas are unstable. Accordingly, the fluctuation of the ore heating and reduction reaction in the preliminary reducing furnace using the gas becomes severe, so that the property of the preliminary reducing light supplied to the molten bath- And thus a vicious cycle in which the ore-melting reduction reaction and the secondary combustion reaction in the molten bath-type reactor become unstable occurs.

Further, even when the coal-fired operation is temporarily smooth, the reduction rate of the preliminary reducing light supplied to the molten bath-type reactor in the preliminary reducing furnace is too low, so that the consumption of coal consumed for melting and reducing the preliminary reducing light is too high relative to the target, It has been reported that the concentration of slag iron oxide in the molten bath-type reactor is too high to cause the molten bath-type reactor refractory material to be excessively eroded.

Although various methods for solving the above problems are applied, it is reported that the improvement effect is insignificant, and the thermal efficiency and the reaction efficiency are gradually decreased due to the above methods, thereby lowering the economical efficiency.

As described above, in order to replace the blast furnace, various melting and reducing steelmaking processes have been independently developed, and operation results of the molten iron manufacturing devices according to the respective melting and reducing steelmaking methods have been continuously reported. Technical achievements, and so on.

Accordingly, there is a need for a composite molten iron manufacturing process (apparatus) in which a plurality of molten iron manufacturing processes (apparatuses) are combined with a new intermediate process (apparatus) so as to maximize the advantages of each molten iron manufacturing apparatus at present .

The present invention relates to a molten iron producing apparatus based on a molten salt bath type melt-gasification furnace based on the above-mentioned fluidized-bed reactors and coal-filled type melting and gasifying furnaces, And more particularly, to a molten iron production apparatus based on a fluidized-bed reactor and a coal-filled type melter-gasifier, and a molten bath-type molten-iron reduction furnace-based molten iron manufacturing apparatus, In the apparatus for manufacturing molten iron based on the fluidized-bed reactors and the coal-filled type melter-gasifier, the molten iron can be stably produced using conventional metallurgical furnaces and raw materials, In the molten bath type melt-reduction furnace-based molten iron manufacturing apparatus, And to provide a composite apparatus for manufacturing molten iron, which uses the charge to produce a molten iron in a stable manner.

According to an embodiment of the present invention, there is provided a method for producing a high-temperature compacted irons, comprising: a first fluidized-bed reactor composed of multi-stages, A compacting device for continuously feeding the high-temperature reducing compacted material conveyed by the conveying device to the melter-gasifier, and a massive general-purpose compacting device for continuously feeding the compacted high- A massive general purpose charging device for continuous supply to the gasification furnace, a massive general charger supplied from the massive general purpose charging device, and a high-temperature combustion gas generated by burning the fine granular material injected from the bottom, A reducing furnace for melting the high-temperature reducing compact fed from the compacting material charging device and for reducing the spectral content in the first fluidized- Gas which supplies a reducing gas to the first fluidized-bed reactor in addition to a reducing gas supplied from the melter-gasifier after a part of the exhaust gas of the first fluidized-bed reactor is branched to remove CO ₂ , ₂ dust removing device, a dust circulating device for separating dust contained in a reducing gas generated in the melter-gasifying furnace and re-introducing the dust into the melter-gasifying furnace, a gas circulating device for removing gas generated in the melter- A first sensible heat recovering device for recovering the sensible heat of the exhaust gas discharged from the first fluidized-bed reacting device; and a second sensible heat recovering device for recovering the sensible heat of the exhaust gas discharged from the first fluidized- A first dry dust collecting device for separating scattered dust contained in the exhaust gas discharged from the first fluidized-bed reactors, A first molten steel producing device including a first gas cooling device for cooling the exhaust gas discharged from the first fluidized-bed reacting furnace;

An iron-bath type melting furnace for producing molten iron and slag through a reaction such as dissolution, combustion, and melt reduction inside the pulverized iron-containing material and pulverized coal introduced into the furnace and discharging it to the outside; A second molten iron manufacturing apparatus including a hot air furnace for producing hot air to be blown, and a cleaning device for cooling and cleaning the gas exhausted from the melting and reducing furnace; And

Wherein the first molten steel producing device is provided between the first molten iron producing device and the second molten iron producing device to connect the first molten iron producing device and the second molten iron producing device, And a third molten steel producing device for diverting a part of the reducing gas supplied to the fluidized-bed reduction reactor and supplying the reduced molten iron to the iron source of the second molten iron producing device by reducing the molten iron to a predetermined level by using the reduced reducing gas. A manufacturing apparatus can be provided.

The third molten iron producing device is provided on a conduit for supplying a high-temperature reducing gas to the first fluidized-bed reduction reactor through a dust circulating device of the first molten iron manufacturing device, in,

A conduit provided at a downstream end of the oxygen mixing passage for diverting a portion of the reducing gas, and

And a second fluidized-bed reactor connected to the conduit and supplied with a reducing gas partially branched from the conduit to convert the converted spectrogram into a powder form.

The second fluidized-bed reactors may be composed of two or more stages or three or more stages.

And a second sensible heat recovery device connected to a downstream end of the second fluidized-bed reactors for recovering exhaust gas heat discharged from the second fluidized-bed reactors.

And a second dry dust collecting device connected to a rear end of the second sensible heat collecting device to separate scattered dust in the exhaust gas.

And a second gas cooling device connected to a downstream end of the second dry type dust collector to cool the exhaust gas.

And a pulverizer reservoir connected to the lowermost second fluidized-bed reactor in the second fluidized-bed reactor to store the pulverized material discharged from the second fluidized-bed reactor through a conduit.

Wherein the reducing agent storage tank is connected to a lower end of the reducing agent storage tank so that the reducing agent is introduced into the iron bath type reducing reducing furnace through a reducing agent reducing agent tank connecting the reducing agent storage tank and the iron- And may include a powder body transfer device for blowing.

The first dry dust collecting apparatus is provided at its lower end with a dust collecting body which is separated from the first dry dust collecting apparatus and discharged from the second fluidized-bed reduction reactor so as to be introduced into the iron- And a first conveyance pipe connecting the first conveyance device and the powder reduction source conveyance pipe.

At the lower end of the second dry dust collecting apparatus, dusts separated from the second dry dust collecting apparatus are introduced into the iron bath type melting and reducing furnace of the second molten iron manufacturing apparatus together with the pulverizing source discharged from the second flow reducing reactor And a second conveyance pipe for connecting the second conveyance device and the powder reduction source conveyance pipe to each other.

The first flow reducing reactor of the first molten steel producing device and the exhaust gas of the second flow reducing reactor are combined to supply the fuel for the hot wind path, and then branched at the rear end of the line branched to the by-product gas line, And may include a hot air furnace furnace gas supply conduit connected thereto.

In the apparatus for manufacturing a composite molten iron which is constituted by a plurality of reaction furnaces in which the iron-containing ores in the form of pulverized or lumpy general coal and powder are directly used according to the embodiment of the present invention, a conventional fluidized- Molten iron is produced in a molten steel production facility based on a coal-fired melt gasification furnace, and a stable or low-grade ore is stably reduced by using a part of the reducing gas stably generated. As a result, the molten iron- It is possible to manufacture molten irons steadily and efficiently using coal.

Therefore, molten iron can be produced at the same time by using ore and coal, which are conventionally known to be unsuitable for metallurgy, as well as conventional ore or coal for metallurgy by the apparatus for manufacturing composite molten iron according to the embodiment of the present invention.

1 is a schematic structural view of a composite molten iron manufacturing apparatus according to an embodiment of the present invention.
2 is a schematic process flow chart showing a material flow in a composite molten iron manufacturing apparatus as an embodiment of a composite molten iron manufacturing apparatus according to an embodiment of the present invention.
FIG. 3 is a table showing a gas property ratio according to a material flow in an apparatus for manufacturing a composite molten iron as an embodiment of the apparatus for manufacturing a composite molten iron according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, so that those skilled in the art can easily carry out the present invention. As will be readily understood by those skilled in the art, the following embodiments may be modified in various ways within the scope and spirit of the present invention. Wherever possible, the same or similar parts are denoted using the same reference numerals in the drawings.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified, and that other specific features, regions, integers, steps, operations, elements, components, and / And the like.

All terms including technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the present invention belongs. Predefined terms are further interpreted as having a meaning consistent with the relevant technical literature and the present disclosure, and are not to be construed as ideal or very formal meanings unless defined otherwise.

1 is a schematic structural view of a composite molten iron manufacturing apparatus according to an embodiment of the present invention.

Referring to FIG. 1, the apparatus for manufacturing molten iron according to an embodiment of the present invention comprises a plurality of reaction furnaces that directly use iron-containing ores in powdered or bulk form,

A plurality of high-temperature compacting apparatuses (B) for producing powdered iron discharged from the first fluidized-bed reactor (A) as a high-temperature compacted compact, a first fluidized- ), A conveying device (D) for conveying the high-temperature reduction compacted material having been crushed to a predetermined size, a compacting device for continuously feeding the high-temperature reducing compacted material conveyed by the conveying device (D) (F) for continuously feeding a charging device (E) and a massive general purpose coal to the melter-gasifier (G), a massive general-purpose coal firing device (F) supplied from the massive general- And the high-temperature reducing compact fed from the compacting material charging device (E) is melted using the high-temperature combustion gas generated by burning the fine carbonaceous material blown from the bottom of the furnace Reduction for spectral reduction The melter-gasifier to supply the switch (G), the first flow is branched to the exhaust gas portion of the reducing furnace (A) to remove the CO ₂ in addition to the reducing gas supplied from (G) to the melter-gasifier of the first flow A CO ₂ removing device M for supplying a reducing gas to the reducing furnace A, a dust removing device for removing dust contained in the reducing gas generated in the melting and gasifying furnace G, The circulation device H partially branches the gas generated in the melter-gasifier G according to the pressure fluctuation of the melter-gasifier G and then discharges the gas to the by-product gas line, A first sensible heat recovery device (J) for recovering the sensible heat of the exhaust gas discharged from the first fluidized-bed reactor (A), a first fluidized- To separate the fly ash contained in the exhaust gas discharged from the For it may include a first dry dust collector (K), and the first gas-cooling device (L) for cooling the exhaust gas discharged from the first fluidized-bed reactor with (A).

Further, the second molten iron producing apparatus of the above-

(A) an iron bath-type melting furnace (a) in which a pulverulent iron-containing material and pulverized coal injected into the furnace are produced as molten iron and slag through a reaction such as dissolution, combustion,

A hot air path (b) for producing hot air blown into the melting and reducing furnace (a) as an oxidant for secondary combustion, and

And a cleaning device (d) for cooling and cleaning the gas discharged from the melting and reducing furnace (a).

The composite molten iron manufacturing apparatus is provided between the first molten iron manufacturing apparatus and the second molten iron manufacturing apparatus to connect the first molten iron manufacturing apparatus to the second molten iron manufacturing apparatus, A part of the reducing gas supplied to the first fluidized-bed reactor (G) is branched off and the reducing ore is reduced to a predetermined level by using the branched reducing gas, And a third molten iron producing device for supplying the molten iron.

The third molten iron producing device comprises a conduit (30) for supplying a high-temperature reducing gas to the first fluidized-bed reactor (A) of the first molten iron producing device via the dust circulating device (H) of the first molten iron manufacturing device (2) for introducing oxygen into the high-temperature reducing gas,

A conduit 31 provided at the rear end of the oxygen mixing furnace 2 to divert a portion of the reducing gas,

And a second fluidized-bed reactor (1) connected to the conduit (31) and supplied with a reducing gas partially branched from the conduit to convert the converted spectrogram into a powder form.

The second fluidized-bed reactors (1) may be composed of two or more stages.

A second sensible heat recovery device (3) connected to a downstream end of the second fluidized-bed reactors (1) for recovering exhaust gas heat discharged from the second fluidized-bed reactors (1)

A second dry dust collecting device (4) connected to the rear end of the second sensible heat recovery device (3) for separating scattered dust in the exhaust gas, and

A second gas cooling device 5 connected to the rear end of the second dry dust collecting device 4 for cooling the exhaust gas, and the like.

In addition, in the second fluidized-bed reactor (1) having a multi-stage structure, a powder-reducing material connected to the lowermost second fluidized-bed reactor and discharged through the conduit (19) from the second fluidized- A reducing agent storage tank 20,

 And is connected to the lower end of the pulverizer reservoir 20 so as to discharge the pulverizer from the pulverizer reservoir 20 to the pulverizer reservoir 20 and the iron bath type molten- And a powder-reducing material conveying device 21 for passing the powder-reducing material conveying device 21 into the iron bath-type melting and reducing furnace (a) of the second molten iron producing device through a powder-reducing material conveying pipe 10 connecting the powder-

In addition, at the lower end of the first dry dust collecting apparatus K, dusts separated from the first dry dust collecting apparatus K are discharged from the second fluidized-bed reactor 1 together with the powder- A first conveying device 6 and a first conveying device 6 for connecting the first conveying device 6 and the powder conveying device conveying pipe 10 so that they can be taken into the iron bath type melting and reducing furnace (7) may be provided.

The dust collecting apparatus according to claim 1, wherein the second dry dust collecting apparatus (4) has a dust collecting body (5), which is separated from the second dry dust collecting apparatus (4) A second conveying device 8 and a second conveying pipe 9 for connecting the second conveying device 8 and the powder conveying device conveying pipe 10 so as to be taken into the iron bath type melting and reducing furnace a, .

In order to supply the fuel required for the hot air path (b) in the second molten iron manufacturing apparatus, the first and second fluidized-bed reactors (A) and (2) of the second fluidized- And a hot-air furnace fuel gas supply conduit 18 branching from the rear end of the line branched to the by-product gas line and connected to the hot air path b.

Hereinafter, the operation of the composite molten iron manufacturing apparatus according to one embodiment of the present invention will be described with reference to FIG.

The reducing gas generated in the melter-gasifier (G) of the first molten steel producing device is combined with the CO ₂ removing gas supplied from the CO ₂ removing device (M) and then passes through the dust circulating device (H) Dust in the gas is removed. A part of the reducing gas from which the dust is removed is branched to the pressure control device I and the remainder is supplied as a high temperature reducing gas to the first fluidized-bed reactor A of the first molten iron producing device through the conduit 30 do.

An oxygen mixing furnace 2 is provided on the conduit 30 and oxygen is blown into the oxygen mixing furnace 2 to burn a part of the hot reducing gas flowing in the oxygen mixing furnace 2 The temperature of the high temperature reducing gas is raised.

At this time, the temperature of the hot reducing gas at the downstream end of the oxygen mixing furnace (2) is lower than the temperature of the first fluidized-bed reactor (A) to which the high-temperature reducing gas is supplied and the second fluidized- It is preferable to set the temperature to about 700 to 780 캜.

The high-temperature reducing gas heated to the temperature at the downstream end of the oxygen mixing furnace (2) is branched to the conduit (31) from the conduit (30) and then supplied to the second flow reduction reactor (1).

The first and second fluidized-bed reactors (1) and (2) are connected to each other. The second fluidized-bed reactors (1) are composed of multiple stages The multi-stage second fluidized-bed reactor (1) The high temperature gas supplied to the lowermost second fluidized-bed reactor and the counter flow system, that is, the spectroscopic and subsidiary materials are supplied from the uppermost stage to the lowermost stage, So that the spectral and subsidiary materials are reduced and fired and converted into the powder-reduced material.

The pulverizing material is discharged from the second low-temperature second fluidized-bed reactor of the second fluidized-bed reactor 1 and stored in the powdered-material storage tank 20, and then transferred to the conveyor device 21 provided at the lower end of the powdered- (A) in the second molten steel producing device through the powder-reducing body conveying pipe (10), dissolving in the iron bath type melting and reducing furnace (a) and then melting and slagging And is converted into charcoal and slag by reaction or the like.

It is preferable that the reduction ratio of the powder light source contained in the pulverizing source discharged from the lowermost end of the second fluidized-bed reactor 1 is about 60 to 70%, which means that at a reduction rate of 60 to 70% or more, And the energy required for melting and slagging of the pulverizing material in the iron bath type melting and reducing furnace (a) in the second molten iron manufacturing apparatus is excessively increased at a reduction ratio of 60 to 70% or less. In order to maintain such a reduction ratio, the second fluidized-bed reactors 1 are preferably composed of, for example, two or three stages.

The exhaust gas discharged from the second fluidized-bed reactor (1) is cooled through the second sensible heat recovery device (3), and the dust contained in the exhaust gas is separated through the second dry dust collector (4) And is discharged from the first fluidized-bed reactor (A) of the first molten iron manufacturing apparatus after being cooled to room temperature in the second gas cooling apparatus (5), and is discharged to the first sensible heat recovery apparatus (J) (K), and the first gas cooling device (L). A portion of the combined gas is supplied to the CO ₂ removal unit M and the remainder is combined with the gas discharged through the pressure control unit I and discharged to the byproduct gas line.

The first dry dust collecting device K and the second dry dust collecting device 4 are respectively provided with a first conveying device 6 and a second conveying device 7, And the second conveying device 7 are connected to the first fluidized-bed reactor A and the second fluidized-bed reactor 1 exhaust gas from the first dry type dust collector K and the second dry type dust collector 4, (10) through the first and second conveying pipes (7, 9), respectively, and the powder is mixed with the powder-reducing material in the powder-reducing material conveying pipe (10) It is blown into the iron bath type melting reduction furnace (a).

An embodiment of producing molten iron using a composite molten iron manufacturing apparatus comprising a plurality of reaction furnaces that directly use iron-containing ores in powdered or massive coals and pulverized coal according to an embodiment of the present invention will be described. In order to meet the object of the present invention, the first molten iron manufacturing apparatus generally has a relatively iron content as shown in [Table 1] to [Table 3] in order to produce molten iron stably and efficiently, Large high-grade ore and high cohesion metallurgical coal were used.

[Table 1] Composition of ore used in the first molten iron manufacturing apparatus

[Table 2] Composition of the coal used in the first molten iron manufacturing apparatus

[Table 3] Composition of Ingredient Used in the First Melting Apparatus

Unlike the first molten iron producing device, the second molten iron producing device uses low-grade ore having a high gangue content and low-cost anthracite having no integrity as shown in [Table 4] to [Table 5].

[Table 4] Composition of ore used in the second molten iron manufacturing apparatus

[Table 5] Composition of the coal used in the second molten iron manufacturing apparatus

In addition, the third molten iron manufacturing apparatus used an additive having the same composition as that of the first molten iron manufacturing apparatus.

FIG. 2 and FIG. 3 show that the first molten iron producing apparatus according to the embodiment of the present invention produces a molten iron of 180 ton per hour and the second molten iron producing apparatus produces 100 ton per hour As a working example of the production process of the present invention.

The following [Table 6] to [Table 9] are the composition table showing the contents of major components of molten iron and slag produced in the first molten iron manufacturing apparatus and the second molten iron manufacturing apparatus according to an embodiment of the present invention .

[Table 6] Composition of production molten iron of the first molten iron manufacturing apparatus

[Table 7] Composition of the production slag of the first molten iron manufacturing apparatus

[Table 8] Composition of production molten iron of the second molten iron manufacturing apparatus

[Table 9] Composition of the production slag of the second molten iron manufacturing apparatus

In the case of the second molten iron manufacturing apparatus, the amount of impurities such as S and P in bar steel using low-cost flue gas and raw material is higher than that of the first molten iron manufacturing apparatus, but the level can be removed in the refining process in general.

As described above, in the first molten iron manufacturing apparatus, molten iron is produced stably and efficiently using a relatively expensive raw material, and as a result, the high-temperature reducing gas stably generating in the first molten iron manufacturing apparatus is used , It shows that the second fluidized-bed reactor (1) produces a stable powdered powder at a level of about 60 to 70% by using lower-order spectral and subsidiary materials.

In addition, this pulverizing material is supplied to the iron source of the iron bath type melting and reducing furnace (a) in the second molten iron producing device, whereby the molten iron is stably produced even by using the low cost anthracite coal as described above in the second molten iron producing device .

A: first fluidized-bed reactor B: high-temperature compacting apparatus
D: Feeding device E: Compacting device
F: Bulk general charge device G: Melting-gasification furnace
H: Dust circulation device I: Pressure control device
J: first sensible heat recovery device K: first dry dust collector
L: first gas cooling apparatus a: iron bath type melting reduction furnace
b: Hot air path d: Cleaning device
1: second fluidized-bed reactor 2:
3: second sensible heat recovery device 4: second dry dust collecting device
5: second gas cooling device 6, 8: first and second feed devices
7, 9: first and second conveying pipes 10: powder reducing conveying pipe
19, 30, 31: conduit 20: atomizer body reservoir
21: Pelletizer transmission pipe

Claims (11)

A plurality of high-temperature compacting apparatuses for producing pulverized iron discharged from the first fluidized-bed reactor into a high-temperature reducing compacted body, a high-temperature compacting apparatus for converting the high-temperature compacted pulverized high- A compacting device for continuously feeding the hot reduction compacted material conveyed by the conveying device to the melter-gasifier, and a massive mass for continuous feeding of the massive general coal to the melter-gasifier, And the high-temperature combustion gas generated by burning the pulverized coal which is blown in from the lower part of the massive coal supplied from the massive general-purpose charging device of the massive furnace to the high-temperature combustion gas supplied from the compacting- Melting gasification for melting the reduced compacted material and for supplying a reducing gas required for spectral reduction in the first fluidized- To said first flow after branching the exhaust gas portion of reduced to remove the CO ₂ CO ₂ removed for supplying a reducing gas to said first fluidized-bed reactor, in addition to the reducing gas supplied in to the melter-gasifier apparatus, the molten A dust circulation apparatus for separating dust contained in a reducing gas generated in a gasification furnace and re-introducing the dust into the melter-gasifier; a gas branching part of the gas generated in the melter- A first sensible heat recovery device for recovering the sensible heat of the exhaust gas discharged from the first fluidized-bed reacting device, and a second sensible heat recovering device for recovering the sensible heat of the exhaust gas discharged from the first fluidized- A first dry dust collecting device for separating scattered dust contained in exhaust gas discharged from the first fluidized-bed reactor, A first apparatus for manufacturing molten iron including a first gas cooling device for cooling the exhaust gas;
An iron-bath type melting furnace for producing molten iron and slag through a reaction such as dissolution, combustion, and melt reduction inside the pulverized iron-containing material and pulverized coal introduced into the furnace and discharging it to the outside; A second molten iron manufacturing apparatus including a hot air furnace for producing hot air to be blown, and a cleaning device for cooling and cleaning the gas exhausted from the melting and reducing furnace; And
Wherein the first molten steel producing device is provided between the first molten iron producing device and the second molten iron producing device to connect the first molten iron producing device and the second molten iron producing device, A third molten steel producing device for diverting a portion of the reducing gas supplied to the fluidized-bed reactors, reducing the ore to a predetermined level by using the branched reducing gas, and supplying it to the iron source of the second molten iron producing device
And a second molten iron manufacturing apparatus. The method according to claim 1,
The third molten iron producing device is provided on a conduit for supplying a high-temperature reducing gas to the first fluidized-bed reduction reactor through a dust circulating device of the first molten iron manufacturing device, in,
A conduit provided at a downstream end of the oxygen mixing passage for diverting a portion of the reducing gas, and
And a second fluidized-bed reactor connected to the conduit and supplied with a reducing gas partially branched from the conduit to convert the converted spectrogram into a powdered raw material. 3. The method of claim 2,
Wherein the second fluidized-bed reacting furnace is composed of two or more stages or three or more stages. The method of claim 3,
And a second sensible heat recovery device connected to a rear end of the second fluidized-bed reactors for recovering exhaust gas heat discharged from the second fluidized-bed reactors. 5. The method of claim 4,
And a second dry dust collecting device connected to a rear end of the second sensible heat collecting device to separate scattered dust in the exhaust gas. 6. The method of claim 5,
And a second gas cooling device connected to a downstream end of the second dry dust collecting device for cooling the exhaust gas. The method according to claim 6,
And a pulverizer reservoir connected to the lowermost second fluidized-bed reactor in the second fluidized-bed reactor for storing the pulverized raw material discharged through the conduit from the second fluidized-bed reactor. 8. The method of claim 7,
Wherein the reducing agent storage tank is connected to a lower end of the reducing agent storage tank so that the reducing agent is introduced into the iron bath type reducing reducing furnace through a reducing agent reducing agent tank connecting the reducing agent storage tank and the iron- And a powder feeder for feeding the reduced powder. 9. The method of claim 8,
The first dry dust collecting apparatus is provided at its lower end with a dust collecting body which is separated from the first dry dust collecting apparatus and discharged from the second fluidized-bed reduction reactor so as to be introduced into the iron- And a first conveying pipe connecting the first conveying device and the powder conveying body conveying pipe. 10. The method of claim 9,
At the lower end of the second dry dust collecting apparatus, dusts separated from the second dry dust collecting apparatus are introduced into the iron bath type melting and reducing furnace of the second molten iron manufacturing apparatus together with the pulverizing source discharged from the second flow reducing reactor And a second conveying pipe for connecting the second conveying device and the powder conveying body conveying pipe to each other. 11. The method of claim 10,
The first flow reducing reactor of the first molten steel producing device and the exhaust gas of the second flow reducing reactor are combined to supply the fuel for the hot wind path, and then branched at the rear end of the line branched to the by-product gas line, And a fuel gas supply conduit connected to the hot gas furnace.

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