DESCRIPTION】
【Technical Field5 】
The present invention relates to an apparatus for manufacturing molten
iron and a method for manufacturing the same. More particularly, the present
invention relates to an apparatus for manufacturing molten iron using reduced
iron that is reduced by a multi-layered reducing furnace, and a method for
10 manufacturing the same.
【Background Art】
A PINEX process that has been recently developed is a technology that
produces iron ore powder into small-sized briquetted iron through a fluidized
bed furnace, and produces bituminous coals into small-sized coal briquettes to
15 produce molten iron by putting the bituminous coals into a melting furnace.
In the PINEX process, particles are removed from common coal (fine
coal) and powder-type iron ore (fine ore) in the initial natural state, and the fine
coal and fine ore passed through a fluidized bed reducing furnace are directly
used. Thus, a sintering process and a coke manufacturing process can be
20 omitted, and accordingly investment cost can be reduced compared to a
conventional blast furnace, and since neither sulfates nor nitrous oxides are
produced, environmental pollution can be prevented.
In addition, since fine ores which account for most of the world’s ore
3
deposits are used, supply and demand of the raw material are free from any
intervention and manufacturing cost is inexpensive compared to a conventional
blast furnace process.
In such a FINEX process, direct reduced iron (DRI) in the fine ore state
is supplied to the fluidized bed reducing furnace, and the direct reduced iro5 n
includes carbon particles.
The carbon particles included in the direct reduced iron deteriorate
transfer efficiency of a screw provided for transferring a raw material, and
deteriorates productivity, thereby causing hardship in continuous production.
10 The above information disclosed in this Background section is only for
enhancement of understanding of the background of the invention and therefore
it may contain information that does not form the prior art that is already known
in this country to a person of ordinary skill in the art.
【DISCLOSURE】
15 【Technical Problem】
The present invention has been made in an effort to provide an
apparatus for manufacturing molten iron that can minimize deterioration of
transfer efficiency of a screw due to carbon particles and improve productivity
with continuous production.
20 【Technical Solution】
An apparatus for manufacturing molten iron according to an exemplary
embodiment of the present invention includes: a plurality of reducing furnaces
manufacturing reduced iron with an iron-containing mixture introduced thereinto;
4
a supply bin connected with the reducing furnaces and to which the reduced
iron is introduced; a reduced iron compressor connected with the supply bin and
manufacturing compacted iron by compressing the reduced iron; and a meltergasifier
manufacturing molten iron by receiving the compacted iron, wherein the
supply bin includes a combustion portion generating flames5 .
The supply bin may include an intake hole through which the reduced
iron is introduced and an exhaust hole through which gas is discharged, and the
combustion portion may be provided below the intake hole.
The supply bin may include an intake hole through which the reduced
10 iron is introduced and an exhaust hole through which gas is discharged, and the
combustion portion may include a first combustion portion provided below the
intake hole and a second combustion portion provided neighboring the exhaust
hole.
The second combustion portion may be provided in an upper portion of
15 the supply bin.
The apparatus for manufacturing molten iron may further include a
screw that enables the reduced iron transferred to the reduced iron compressor
from the supply bin to be moved while being rotated.
Another exemplary embodiment of the present invention provides a
20 method for manufacturing molten iron. The method includes: manufacturing
reduced iron by supplying an iron-containing mixture to a reducing furnace;
eliminating carbon in the reduced iron; supplying carbon-eliminated reduced
iron to a reduced iron compressor; manufacturing compacted iron by
compressing the reduced iron; and manufacturing molten iron by melting the
5
compacted iron.
The eliminating carbon and the supplying of the reduced iron may be
simultaneously performed in a supply bin connected with the reducing furnace.
The eliminating carbon may be performed at a temperature between
1000 °C and 1300 °C5 .
The reduced iron may move downward while rotating in the supply bin
due a speed generated when the reduced iron is supplied to the supply bin and
then supplied to the reduced iron compressor.
【Advantageous Effects】
10 When molten iron is manufactured according the present invention,
deterioration of transfer efficiency of a screw due to an impurity such as carbon
can be prevented.
Thus, molten iron is manufactured by continuously injecting compacted
iron into a melter-gasifier, thereby improving productivity.
15 【Description of the Drawings】
FIG. 1 is a schematic diagram of an apparatus for manufacturing molten
iron according to an exemplary embodiment of the present invention.
FIG. 2 is a schematic cross-sectional view of a supply bin according to
the exemplary embodiment of the present invention.
20 FIG. 3 is a flowchart provided for description of a method for
manufacturing molten iron according to an exemplary embodiment of the
present invention.
【Mode for Invention】
6
The present invention will be described more fully hereinafter with
reference to the accompanying drawings, in which exemplary embodiments of
the invention are shown. 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. Like referenc5 e
numerals are used for like components in the drawings.
The terminologies used hereafter are only for describing a specific
exemplary embodiment and are not intended to limit the present invention.
Singular terms used herein include plural terms unless phrases clearly express
10 opposite meanings. The term ‘including’ used herein refers to concrete
specific characteristics, regions, positive numbers, steps, operations, elements,
and/or components, without limiting existence or addition of other specific
characteristics, regions, positive numbers, steps, operations, elements, and/or
components.
15 All the terms, including technical terms and scientific terms used
hereafter, have the same meanings as those that those skilled in the art
generally understand. The terms defined in dictionaries should be construed
as having meanings corresponding to the related prior art documents and those
stated herein, and are not to be construed as being ideal or official, if not
20 defined otherwise.
FIG. 1 is a schematic diagram of an apparatus for manufacturing molten
iron according to an exemplary embodiment of the present invention, and FIG. 2
is a schematic cross-sectional view of a supply bin according to the exemplary
embodiment of the present invention.
7
As shown in FIG. 1, a molten iron manufacturing apparatus 1000
according to an exemplary embodiment of the present invention includes a
melter-gasifier 120, a plurality of fluidized bed reducing furnaces (hereinafter
referred to as reducing furnaces) 110, and a reduced iron compressor 130.
Here, a compressed reduced iron storage bin may be omitted. The molten iro5 n
manufacturing apparatus 100 may include other devices as necessary.
A drier 60 is provided for drying ore supplied to the reducing furnace 110,
the ore may be fine ore for manufacturing the molten iron and a mine-extracted
iron-containing mixture, which is a fine sub-material, and the iron-containing
10 mixture may be iron ore or coal. In this case, fine iron ore may be used as the
iron ore, and a sub-material such as limestone, dolomite, and the like may be
mixed as necessary.
The reducing furnace 110, receives the iron-containing mixture dried by
the drier 60, reduces the iron-containing mixture through multi-stages, and
15 discharges the reduced iron-containing mixture to the supply bin 200. The
plurality of reducing furnaces 110 may be connected in series by connection
pipes, and the iron-containing mixture is reduced through multi-stages by the
plurality of reducing furnaces 110.
For example, as shown in FIG. 1, if three reducing furnaces 110 are
20 connected, a first reducing furnace where the iron-containing mixture is
primarily reduced for manufacturing molten iron, a second reducing furnace
where the primarily reduced iron-containing mixture is secondarily reduced, and
a final reducing furnace where the secondarily reduced iron-containing mixture
is finally reduced to fine direct reduced iron may be included.
8
The respective reducing furnaces may be connected with each other by
connection pipes.
In FIG. 1, three reducing furnaces 110 are illustrated for multi-stage
reduction, but this is not restrictive, and at least one fluidized bed reducing
furnace may be used. Further, the reducing furnace shown in FIG. 1 is 5 a
fluidized bed reducing furnace, but the present invention is not limited thereto.
A different type of reducing furnace may also be used.
The supply bin 200 stores reduced iron reduced through the reducing
furnaces 110. The supply bin 200 includes an inclined surface, and the
10 reduced iron may be discharged to the outside through the inclined surface. In
this case, the reduced iron may be discharged in several directions (not shown)
through a plurality of outlets (not shown) provided in a lower side of the supply
bin 200.
Specifically, as shown in FIG. 2, the supply bin 200 includes an intake
15 hole 27 through which reduced iron is introduced from the reducing furnaces
110 and an exhaust hole 29 through which gas is discharged. In addition, the
supply bin 200 may include a first combustion portion 31 disposed below the
intake hole 27 and a second combustion portion 33 disposed neighboring the
exhaust hole 29.
20 The first combustion portion 31 and the second combustion portion 33
may be provided as a type of burner that throws a flame of a high temperature
between 1000 °C and 1300 °C to eliminate carbon from the reducing iron.
Since the reduced iron is introduced to the supply bin 200 at a constant
velocity through the intake hole 27, the reduced iron moves downward while
9
rotating in the supply bin 200 by a rotation force generated as the reduced iron
is being introduced into the supply bin 200 and then supplied to a reduced iron
compressor.
In this case, an impurity included in the reduced iron, such as carbon
and the like, is eliminated by being burned by the first and second combustio5 n
portions 31 and 33.
That is, the reduced iron introduced through the intake hole 27 moves
downward while rotating in the supply bin 200, and the impurity included in the
reduced iron is eliminated when the reduced iron moving downward while
10 rotating in the supply bin 200 and passes through the high-temperature flame
thrown toward the reduced iron from the first combustion portion 31.
A supply amount of reduced iron may be adjusted in consideration of the
amount of reduced iron being burned by the first combustion portion 31.
In addition, the second combustion portion 33 is disposed neighboring
15 the exhaust hole 29 through which gas is discharged, and burns the reduced
iron in an upper portion of the supply bin 200.
Power of the flame thrown from the first combustion portion 31 may be
unstable compared to that of the second combustion portion 33, but has a
higher burning rate than the second combustion portion 33.
20 Thus, either the first combustion portion 31 or the second combustion
portion 33 may be omitted as necessary.
Meanwhile, the reduced iron supplied to the supply bin 200 may be
supplied to the reduced iron compressor 130 through a screw.
In the present exemplary embodiment, the impurity of the reduced iron,
10
particularly, carbon attached to the screw and thus deteriorating transfer
efficiency, is eliminated in the supply bin, and therefore deterioration of transfer
efficiency due to the impurity such as carbon can be prevented.
The reduced iron compressor 400 includes a hopper 150 and a pair of
rolls 170. The hopper 150 is connected with the exhaust hole 29 of the suppl5 y
bin 200 and includes the screw for transferring the reduced iron to the pair of
rolls 170, and the pair of rolls 170 briquette the reduced iron supplied from the
hopper 150 by compressing the same. The reduced iron compressor 400 may
further include a crusher crushing compacted iron compressed by the pair of
10 rolls 170 into a constant size, and a storage bin temporarily storing the crushed
compacted iron and then supplying the crushed compacted iron to the meltergasifier
300.
Lump coal or shaped coal realized by compressing fine coal is supplied
to the melter-gasifier 300 to form a coal packed bed. The compacted iron is
15 melted using the coal packed bed as a heat source such that molten iron is
manufactured.
Meanwhile, high-temperature reduction gas generated from a
combustion reaction of oxygen supplied to the melter-gasifier 120 and the coal
packed bed is connected with a rear end of the final reducing furnace 110
20 through a reduction gas supply pipe. In addition, the high-temperature
reduction gas supplied to the final reducing furnace 110 is sequentially supplied
to the reducing furnaces 110 so as to be used as a reducing agent and fluidized
gas. In this case, a cyclone may be provided to prevent fine powder included
in the reduction gas discharged from the melter-gasifier 120 from being
11
scattered. The fine powder collected by the cyclone is introduced back to the
melter-gasifier 120.
A detailed structure of the melter-gasifier 120 can be readily understood
by those skilled in the art, and therefore more detailed description is omitted.
FIG. 3 is a flowchart provided for description of a method fo5 r
manufacturing molten iron according to an exemplary embodiment of the
present invention. The method shown in FIG. 3 manufactures molten iron
using the apparatus for manufacturing the molten iron of FIG. 1 and FIG. 2.
As shown in FIG. 3, the method for manufacturing the molten iron
10 according to the present exemplary embodiment includes: putting an ironcontaining
mixture into a reducing furnace (S100); manufacturing reduced iron
(S102); supplying the reduced iron to a supply bin (S104); eliminating carbon
(S106); manufacturing compacted iron (S108); and manufacturing molten iron
by injecting the compacted iron into a melter-gasifier.
15 That is, an iron-containing mixture dried through a drier is supplied to a
reducing furnace (S100). The mixture may be may fine ore for manufacturing
molten iron and a mine-extracted iron-containing mixture, which is a fine submaterial,
and the iron-containing mixture may be iron ore or coal. In this case,
fine iron ore may be used as the iron ore, and a sub-material such as limestone,
20 dolomite, and the like may be mixed as necessary.
Next, the mixture supplied to the reducing furnace is reduced through
multiple stages by a plurality of reducing furnaces such that reduced iron is
manufactured (S102). The reduced iron is supplied to the supply bin (S104),
and an impurity such as carbon included in the reduced iron is eliminated by
12
first and second combustion portions as the reduced iron is being supplied to
the supply bin (S106).
In this case, the first combustion portion and the second combustion
portion throw flames at a high temperature between 1000 °C and 1300 °C so as
to eliminate carbon in the reduced iron5 .
In addition, the reduced iron of which the impurity is eliminated moves
downward while rotating at the inside of the supply bin at a speed generated as
the reduced iron is being supplied through an intake hole and then supplied to a
reduced iron compressor such that compacted iron is manufactured (S108).
10 After that, the compacted iron is supplied to the melter-gasifier 300 and
then melted by using a coal packed bed as a heat source such that molten iron
is manufactured (S110).
While this invention has been described in connection with what is
presently considered to be practical exemplary embodiments, it is to be
15 understood that the invention is not limited to the disclosed embodiments, but,
on the contrary, is intended to cover various modifications and equivalent
arrangements included within the spirit and scope of the appended claims.
13
We claim:-
【Claim 1】
An apparatus for manufacturing molten iron, comprising:
a plurality of reducing furnaces manufacturing reduced iron with an ironcontaining
mixture introduced thereinto5 ;
a supply bin connected with the reducing furnaces and to which the
reduced iron is introduced;
a reduced iron compressor connected with the supply bin and
manufacturing compacted iron by compressing the reduced iron; and
10 a melter-gasifier manufacturing molten iron by receiving the compacted
iron,
wherein the supply bin comprises a combustion portion for eliminating
carbon in the reduced iron.
15 【Claim 2】
The apparatus for manufacturing molten iron of claim 1, wherein the
supply bin comprises an intake hole through which the reduced iron is
introduced and an exhaust hole through which gas is discharged, and the
combustion portion is provided below the intake hole.
20
【Claim 3】
The apparatus for manufacturing molten iron of claim 1, wherein the
supply bin comprises an intake hole through which the reduced iron is
14
introduced and an exhaust hole through which gas is discharged, and the
combustion portion includes a first combustion portion provided below the
intake hole and a second combustion portion provided neighboring the exhaust
hole.
5
【Claim 4】
The apparatus for manufacturing molten iron of claim 3, wherein the
second combustion portion is provided in an upper portion of the supply bin.
10 【Claim 5】
The apparatus for manufacturing molten iron of claim 4, further
comprising a screw that enables the reduced iron transferred to the reduced
iron compressor from the supply bin to be moved while being rotated.
15 【Claim 6】
A method for manufacturing molten iron, comprising:
manufacturing reduced iron by supplying an iron-containing mixture to a
reducing furnace;
eliminating carbon in the reduced iron;
20 supplying carbon-eliminated reduced iron to a reduced iron compressor;
manufacturing compacted iron by compressing the reduced iron; and
manufacturing molten iron by melting the compacted iron.
15
【Claim 7】
The method for manufacturing molten iron of claim 6, wherein the
eliminating carbon and the supplying of the reduced iron are simultaneously
performed in a supply bin connected with the reducing furnace.
5
【Claim 8】
The method for manufacturing molten iron of claim 7, wherein the
eliminating carbon is performed at a temperature between 1000 °C and 1300 °C.
10 【Claim 9】
The method for manufacturing molten iron of claim 7, wherein the
reduced iron moves downward while rotating in the supply bin due a speed
generated when the reduced iron is supplied to the supply bin and then supplied
to the reduced iron compressor.