WO2017052112A1

WO2017052112A1 - Molten iron manufacturing apparatus and molten iron manufacturing method

Info

Publication number: WO2017052112A1
Application number: PCT/KR2016/009974
Authority: WO
Inventors: 권기웅; 배진찬
Original assignee: 주식회사 포스코
Priority date: 2015-09-21
Filing date: 2016-09-06
Publication date: 2017-03-30
Also published as: WO2017052112A9

Abstract

Provided is a molten iron manufacturing method manufacturing molten iron by rapidly heating coal after charging the coal in a dome part of a melting and gasifying furnace of a molten iron manufacturing apparatus, so as to form char in a large size by reducing the degradation of coal briquettes charged in the melting and gasifying furnace, the molten iron manufacturing apparatus comprising: the melting and gasifying furnace charging reduced iron; and a reducing furnace connected to the melting and gasifying furnace, and providing the reduced iron, and the method comprising the steps of: i) carbonizing the coal and providing the carbonized coal; ii) providing the reduced iron obtained by reducing iron ore in the reducing furnace; and iii) providing the molten iron by charging the carbonized coal and the reduced iron in the melting and gasifying furnace.

Description

【Specification】

[Name of invention]

Molten iron manufacturing apparatus and molten iron manufacturing method

Technical Field

Disclosed are a molten iron manufacturing apparatus and a manufacturing method.

[Technique to become background of invention]

In the molten iron reduction method, a reduction furnace for reducing iron ore and a melt gasification furnace for melting reduced iron ore are used. When iron ore is melted in a melt gasifier, coal briquettes are charged into the melt gasifier as a heat source for melting iron ore. The reduced iron is melted in the molten gasifier and then converted to molten iron and slag and then discharged to the outside. The coal briquettes charged into the melt gasifier form a coal seam layer. Oxygen is blown through the tuyere provided in the melt gasifier, and then burns the coal seam layer to generate combustion gas. The combustion gas is converted into a high temperature reducing gas while rising through the coal seam bed. The high temperature reducing gas is discharged to the outside of the melt gasification furnace and supplied to the reduction furnace as reducing gas.

Coal briquettes used in the molten iron reduction method are made of briquettes by molding powdered coal, and are supplied to a molten gasifier to provide heat required for melting reduced iron. The coal briquettes charged into the melt gasifier are converted into char by pyrolysis reaction. The particle size of the fin has the greatest effect on the productivity and efficiency of the melt gasification furnace. In the process of converting the coal briquettes charged into the molten gas into molten gas, a lot of differentiation occurs, and as the size of the seat decreases, air permeability and liquid permeability decrease and productivity and efficiency decrease. In addition, a complicated process is required to deal with the hot dust generated as the coal briquettes are differentiated.

[Content of invention]

Problem to be solved

Provided is a molten iron manufacturing apparatus and a molten iron manufacturing method that can reduce the differentiation of the coal briquettes charged in the melt gasifier to form a large size of the char.

In addition, by omitting the process for dust reprocessing, it provides an efficient and simplified molten iron manufacturing apparatus and molten iron manufacturing method compared to the existing processes. In addition, it is possible to minimize the waste of fuel due to reducing gas cooling Provided is a molten iron manufacturing apparatus and a molten iron manufacturing method.

[Measures of problem]

In the molten iron manufacturing method according to an embodiment of the present invention, the molten gasifier is charged with a reduced iron, and the dome part of the molten gasifier of the molten iron manufacturing apparatus including a reducing furnace connected to the molten gasifier, and providing the reduced iron. A method of manufacturing molten iron by charging coal and rapidly heating the coal, the method comprising the steps of: i) drying and providing coal; ii) providing reduced iron from which iron ore is reduced in a reduction furnace; and iii) melting the carbonized coal and reduced iron. Charging the gasifier to provide molten iron.

In the step of providing the reduced iron, the reducing furnace may be a fluidized bed reduction furnace or a layered bed reduction furnace.

In the step of providing the coal by distilling, it can be charged into the molten gasifier by providing the hot distilled coal.

The molten iron manufacturing method according to an embodiment of the present invention may further include a step of directly supplying the reducing gas generated from the molten gasifier to the reduction furnace. In the step of directly supplying the reduced gas generated in the melt gasification furnace to the reduction furnace, it may not include the step of removing the fine powder from the reducing gas and the step of re-injecting the fine powder into the melt gasifier to combust.

The method may further include bypassing and discharging at least a portion of the reducing gas supplied to the reducing furnace in the step of directly supplying the reducing gas generated from the melting gasifier to the reducing furnace.

The molten iron manufacturing method according to an embodiment of the present invention may further include a step of mixing with the reducing gas supplied to the reduction after removing the exhaust gas co ₂ discharged from the reduction furnace.

Apparatus for manufacturing molten iron according to an embodiment of the present invention, the melter-gasifier is reduced iron is charged, and to connect to said melter-gasifier is provided with the reduced iron-ring-membered ^ Four-hamhi "W eu ⁱ for sangkkeo eu melting ^"as an apparatus for manufacturing molten iron is charged into the coal is rapidly heated to deumbu to the gasifier, connecting the melter-gasifier to the dry distillation of coal, and may further include a coal dry distillation provided in the melter-gasifier. The reduction furnace may be a fluidized bed reduction furnace or a layered bed reduction furnace. The coal distillation unit may have a structure in which coal is dried to provide high temperature steam to a molten gasifier.

The apparatus for manufacturing molten iron according to an embodiment of the present invention may further include a reducing gas line which is directly connected between the melting gasifier and the reducing furnace to directly supply the reducing gas generated in the melting gasifier to the reducing furnace.

The molten iron manufacturing apparatus according to an embodiment of the present invention, the remover is connected to the exhaust gas line is connected to the reducing furnace to remove the exhaust gas, the remover to remove the co ₂ from the exhaust gas, the remover and the reducing gas line is connected to the remover It may further include a recycling line for supplying the rough gas to the reducing gas line. The molten iron manufacturing apparatus according to an embodiment of the present invention, the

It may further include a branching line which is branched from the reducing gas line is connected to the exhaust gas line of the reducing furnace to bypass at least a portion of the reducing gas supplied to the reducing furnace to discharge.

【Effects of the Invention】

By reducing the differentiation of the coal briquettes charged into the melt gasifier to form a larger size of the furnace, the productivity and efficiency of molten iron in the melt gasifier is improved.

In addition, there is no need to treat dust, which simplifies the process.

In addition, by minimizing waste of fuel, production costs are reduced.

[Brief Description of Drawings]

1 is a schematic diagram of a molten iron manufacturing apparatus according to the present embodiment.

2 is a schematic view of a molten iron manufacturing apparatus according to another embodiment.

[Specific contents to carry out invention]

Terms such as first, second, and third are used to describe various parts, components, regions, layers, and / or sections, but are not limited to these. These terms are only used to distinguish one part, component, region, layer or section from another part, component, region, layer or section. Thus, the eu minutes to describe components in less than ₇ _ ^ ^ region eucheung ^ eu addition section - is eu of the present invention eu eu-pan-eu above beotkkeo - a second part, component, region within a range that does Dodge eu, It may be referred to as a layer or section.

The terminology used herein is for reference only to specific embodiments and is not intended to limit the invention. Singular used here The forms also include the plural forms unless the phrases clearly indicate the opposite. As used herein, the meaning of "comprising" embodies a particular characteristic, region, integer, step, operation, element and / or component, and the presence of another characteristic, region, integer, step, operation, element and / or component or It does not exclude the addition.

Although not defined otherwise, all terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. Commonly defined terms used are additionally interpreted to have a meaning consistent with the related technical literature and the presently disclosed contents, and are not interpreted in an ideal or very formal sense unless defined.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

1 schematically shows a molten iron manufacturing apparatus 100 using coal produced according to the present embodiment. The structure of the apparatus for manufacturing molten iron 100 of FIG. 1 is merely for illustrating the present invention, and the present invention is not limited thereto. Thus

1, the apparatus for manufacturing molten iron 100 can be modified in various forms.

As shown in FIG. 1, the apparatus for manufacturing molten iron 100 is used for distilling coal into a molten gasifier by distilling coal 10 into a molten gasifier 10, a plurality of fluidized-bed reduction furnaces 20, a reduced iron compression device 30, and coal. Coal distiller 40.

The coal distilled from the coal distillation unit 40 is charged into the melt gasifier 10. The iron ore is supplied to a plurality of reducing furnaces 20 having a fluidized bed, and is made of reduced iron while flowing by the reducing gas supplied from the melt gasifier 10 to the fluidized-bed reduction furnace 20. Reduced iron is reduced by the reduced iron compression device (30).

ᅳ 一 "가 了了 ^ 了 ᅳ ᅳ" 了-탄 탄 了了-了 장 장 장 장 장 장 장 입 입 입 입 입 된다 된다 용융 된다 된다. On the outer wall

A blowhole 130 is provided to blow oxygen. Oxygen is blown into the coal packed bed to form a combustion zone. The charged coal is burned in a combustion zone to reduce gas. Can be generated.

The coal distillator 40 distills coal to remove volatiles. The coal distillation unit 40 is applicable to all of the structural surfaces that can coal coal. For example, the coal dryer can use the coke oven of the existing coke manufacturing process. In the molten iron manufacturing apparatus of this embodiment, since the quality of char required is lower than the quality of char required to be used in the blast furnace, it is possible to use inexpensive coal without using expensive coal.

In the present embodiment, the coal distillation unit 40 is carbonized to produce coal in a char state and charged into a molten gasifier. By charging the hot distilled fuel into the molten gasifier in advance, it is possible to prevent the generation of dust. That is, the dome portion 101, which is a larger space than the other portions, is formed in the upper part of the melt gasification furnace 10. In the conventional case, coal charged into the dome portion 101 by hot reducing gas existing in the dome portion is formed. It can be easily differentiated by pyrolysis. However, according to the present embodiment, the coal is charged into the molten gasifier at high temperature through the coal distillation unit 40 and charged into the molten gasifier, thereby suppressing the differentiation of coal in the molten gasifier and minimizing the amount of dust generated.

The coal distillation unit 40 distills coal into a desired temperature rising pattern before charging the coal into a melting gasifier. Accordingly, the differentiation of coal in the melt gasifier is suppressed, so that the size of the fin can be made larger, thereby increasing the productivity and thermal efficiency of the melt gasifier.

The coal is also charged into the molten gasifier 10 in a depleted state with depletion. Since the amount of fuel used in the melt gasifier is determined by the heat balance, it is possible to reduce the fuel consumption of the melt gasifier by the amount of heat contained.

The reducing gas generated in the melt gasifier 10 is supplied to the reduction furnace through the reducing gas line (12). In this embodiment, the reducing gas line (12) is ^u molten large screen ¾ ^ (_16-) - with reduced "eusa-eottyeo i eu remote-connection-eu toemeo melt-7 - ^^

It has a structure of directly supplying the generated reducing gas to the reduction furnace. Here, the direct connection refers to a structure integrated between the melting gasifier and the reduction furnace without going through a separate process or facility. Thus, the gas produced in the melt gasifier The high temperature reducing gas is directly supplied to the reduction furnace through the reducing gas line 12. In the conventional case, in order to treat dust generated when the coal briquettes charged into the melt gasifier is differentiated, a cyclone and a dust burner facility are provided in the melt gasifier. Thus, conventionally, the reducing gas generated in the melt gasifier is first removed through the cyclone dust. Dust collected and removed from the cyclone is blown back into the melt gasifier with oxygen through a dust burner and combusted.

As such, in the related art, a separate facility for treating dust is required, whereas in the present embodiment, a facility for dust treatment is not required. That is, by charging coal pre-dried coal through the coal distillation unit into the molten gasifier, there are no volatile matters generated in the molten gasifier and the cyclones and dust burners necessary for dust collection, combustion, and volatile decomposition. It is not necessary.

Accordingly, in the present embodiment, there is almost no generation of dust in the melt gasifier, so that the reducing gas can be directly supplied to the reduction furnace 20. That is, the manufacturing apparatus of the present embodiment can lower the temperature of the dome portion 101 by melting gasification, because the dust burner connected to the melting gasification furnace is unnecessary. Accordingly, the temperature of the reducing gas discharged from the dome portion of the melt gasification furnace can be lowered as compared with the conventional one. As is known, the temperature of the reducing gas supplied to the reduction furnace should be maintained at around 700 ^° C. In the related art, the temperature of the reducing gas generated in the melt gasifier is too high, and thus, the temperature of the reducing gas cannot be directly supplied to the reducing furnace. However, in the present embodiment, as dust treatment is not necessary

A reducing gas line 12 is directly connected between the melting gasifier and the reducing furnace.

The reducing gas generated in the melt gasifier can be directly supplied to the reduction furnace. In addition to the above-described structure, there一to lower the temperature of the reducing gas supplied to the reducing eu ^ ^ specific command - ^ is the reduced eu ^{^"a"} ^ i ^ eu moans euha dre-eu crude yeokgeo Publications " g ^ f ^ do——For the sake of clarity, the manufacturing apparatus of this embodiment is connected to the exhaust gas line 24 installed in the reduction furnace 20 and removes the remover 50 for removing C0 ₂ from the exhaust gas discharged through the exhaust gas line. And between the remover 50 and the reducing gas line 12. The low temperature cooling gas connected to the remover to the reducing gas line (12)

It may further include a recycling line 52 to supply. Even in such a structure, since the temperature of the reducing gas supplied to the reduction furnace through the reducing gas line 12 is relatively low as compared with the related art, it is possible to further reduce the amount of cooling gas used for temperature control.

As such, the amount of cooling gas used to lower the temperature of the reducing gas may be minimized, or the cooling gas may not be used at all, thereby increasing thermal efficiency and reducing fuel consumption.

2 is a molten iron manufacturing apparatus according to another embodiment of the present invention

Shown schematically. The structure of the apparatus for manufacturing molten iron 200 of FIG. 2 is merely for illustrating the present invention, and the present invention is not limited thereto. Therefore, the apparatus for manufacturing molten iron 200 of FIG. 2 may be modified in various forms. Of FIG. 2

The structure of the apparatus for manufacturing molten iron 200 is the structure of the apparatus for manufacturing molten iron 100 of FIG.

Since they are similar, the same reference numerals are used for the same parts, and detailed description thereof will be omitted.

As shown in FIG. 2, the molten iron manufacturing apparatus 200 includes a molten gasifier 10, a packed-bed reduction reactor 22, and a coal distillator 40 for distilling coal into the molten gasifier. do. In addition, other devices may be included as needed. In the layered layer reduction furnace 22, iron ore is charged and reduced. The iron ore charged into the layered layer reduction furnace 22 is preliminarily dried and then made of reduced iron while passing through the layered layer type reducing furnace 22. Layered Reduction Furnace 22

As a reducing furnace, a reducing gas is supplied from the melting gasifier 10 to form a layered layer therein.

The coal distillation unit 40 produces coal in a high temperature char state by distilling the coal at a high temperature, and charging the coal into a molten gasifier. By charging the hot distilled fuel into the molten gasifier in advance, it is possible to prevent the generation of dust. Thus, in this embodiment an apparatus for manufacturing molten iron 200, back-up "^ eurae-sulfonic-server-to ^{^"} server-compost-turn eu's ^"over-the clone-and一a dust burner is not necessary.

In the case of the molten iron manufacturing apparatus 200 shown in FIG. 2, since the dust burner is not provided, the silver gas of the reducing gas discharged from the molten gasifier is lowered. There is no need for a cooling gas for temperature control of the reducing gas. Thus, as shown in Figure 2, between the melt gasifier 10 and the reduction furnace 22

The reducing gas line 12 is connected directly and has a structure of directly supplying the reducing gas generated in the molten gasifier 10 to the reducing furnace 20. Therefore, it is possible to reduce the fuel cost by reducing the amount of heat that is conventionally discarded for cooling the high temperature reducing gas.

In addition, the molten iron manufacturing apparatus according to the present embodiment, the

And a branching line 14 which is branched from the reducing gas line 12 and connected to the exhaust gas line 24 of the reducing furnace and bypasses and discharges at least a portion of the reducing gas supplied to the reducing furnace.

In this case, if necessary, reducing gas is discharged through the branch line (14).

By discharging to the exhaust gas line 24, the flow of reducing gas can be stabilized more.

Hereinafter, the molten iron manufacturing process according to an embodiment of the present invention will be described. The molten iron manufacturing process described below may be variously modified, and the present invention is not limited thereto.

The molten iron manufacturing process of the present embodiment may include the steps of providing coal by distilling coal, providing reduced iron by reducing iron ore in a reduction furnace, and charging molten coal and reduced iron in a melting gasifier to provide molten iron. have. In the step of providing the coal by distilling off, the prepared coal is distilled off to remove volatiles. The kind of coal is not specifically limited, A single coal type or various types of coal can be mixed and used. Specifically, lignite or sub-bituminous coal, which is a low grade coal, may be used. Coal removed from the volatilization process through a dry distillation process is prepared in a hot char state and is devoted to heat.

It is charged to the melt gasifier. The iron ore is reduced through a fluidized bed reduction furnace or a layered bed reduction furnace and charged into a melt gasifier.

The reduced iron is charged and melted together with the coal that has been distilled into the melt gasifier. As the coal distilled into the molten gasifier is charged, the differentiation of coal in the molten gasifier is suppressed, and the generation of dust is minimized. Therefore, the dust treatment process can be omitted and the temperature of the reducing gas discharged from the molten gasifier is increased. It can be lowered than before. Therefore, the reducing gas generated from the molten gasifier in the melting process without the dust treatment process can be directly supplied to the reduction furnace through the reducing gas line.

In the case of a structure using a fluidized bed reduction furnace, a process for lowering the temperature of the reducing gas supplied to the reduction furnace may be further processed. To this end, the production method of the present embodiment can be supplied to the reduction furnace by mixing the cooling gas of the low temperature cooling gas to the reduction gas after removing C0 ₂ from the exhaust gas discharged from the reduction furnace.

As such, even when the reducing gas is directly supplied to the reduction furnace to use no cooling gas, or when the cooling gas is mixed with the reducing gas to reduce the temperature of the reducing gas, the amount of cooling gas used can be reduced. In addition, in the case of the structure using the layered layer reduction furnace, in the step of directly supplying the reducing gas generated from the molten gasifier to the reduction furnace, it is possible to bypass at least a portion of the reducing gas supplied to the reduction furnace to discharge. . Accordingly, if necessary, by directly exhausting the reducing gas without supplying it to the reduction furnace, the flow of the reducing gas can be more stabilized.

Although the present invention has been described above, it will be readily understood by those skilled in the art that various modifications and variations are possible without departing from the spirit and scope of the claims set out below.

[Explanation of code]

10 Melting Gasifier Reduction Gas Line

20 Fluidized Bed Reduction Furnace Layered Bed Reduction Furnace

24 Exhaust Gas Line Reduced Iron Compressor

40 Coal Dryer Remover

52 recycling line

Claims

[Claim]

[Claim 1]

The molten iron manufacturing apparatus of the molten iron manufacturing apparatus including a molten gasifier to be charged with reduced iron, and a reducing furnace connected to the molten gasifier and providing the reduced iron.

As a method of manufacturing molten iron by charging coal at a dome part of a melt gasifier and rapidly heating it,

i) providing coal by distilling coal, ii) providing reduced iron obtained by reducing iron ore in a reduction furnace, and Hi) charging molten coal and reduced iron into a molten gas furnace to provide molten iron. Manufacturing method.

[Claim 2]

The method of claim 1,

In the step of providing the reduced iron, the reducing furnace is a molten iron manufacturing method is a fluidized bed-type reduction layer or layered layer reduction.

[Claim 3]

The method of claim 1,

In the step of carbonizing and providing the coal, molten coal is supplied to the molten gasifier by providing the coal in a high temperature left state.

[Claim 4]

The method according to any one of claims 1 to 3,

The method for producing molten iron further comprising the step of directly supplying the reduced-gas generated from the melt gasifier to the reduction furnace.

[Claim 5]

The method of claim 4, wherein

In the step of directly supplying the reducing gas generated from the molten gasifier to the reduction furnace, bypassing at least a portion of the reducing gas supplied to the reduction furnace and further comprising the step of discharging.

[Claim 6]

The method of claim 4,

After removing the exhaust gas discharged from the reduction furnace C0 _{2 to} the reduction furnace

The molten iron manufacturing method further comprising the step of mixing with the reducing gas supplied.

[Claim 7]

An apparatus for producing molten iron in which coal is charged into a dome of the molten gasifier and rapidly heated, including a molten gasifier in which reduced iron is charged, and a reducing furnace connected to the molten gasifier and providing the reduced iron.

The molten iron manufacturing apparatus further comprises a coal dryer for supplying the molten gasifier by connecting the molten gasifier to dry coal.

[Claim 8]

The method of claim 7,

The reducing furnace is a molten iron manufacturing apparatus which is a fluidized bed reduction furnace or packed bed reduction furnace.

[Claim 91]

The method of claim 7,

The coal distillation unit is a molten iron manufacturing apparatus having a structure in which coal is dried to provide high temperature steam to a molten gasifier.

[Claim 10]

The method according to any one of claims 7 to 9,

And a reducing gas line directly connected between the melt gasifier and the reduction furnace to directly supply the reducing gas generated in the melt gasifier to the reduction furnace.

[Claim 11]

The method of claim 10,

A remover connected to an exhaust gas line connected to the reducing furnace to remove co ₂ from the exhaust gas, and a recycle line connected between the remover and the reducing gas line to supply a gas passed through the remover to the reducing gas line. A molten iron manufacturing apparatus further comprising.

[Claim 12]

The method of claim 10,

And a branching line which is branched from the reducing gas line and connected to an exhaust gas line of the reducing furnace and bypasses at least a portion of the reducing gas supplied to the reducing furnace.