METHOD OF MANUFACTURING MOLTEN IRON USING IMPROVED CHARGING METHOD AND APPARATUS FOR MANUFACTURING MOLTEN
IRON USING THE SAME
CROSS-REFERENCE TO RELATED APPLICATION
This application claims priority to and the benefit of Korean Patent Application No. 10-2014-0186551 filed in the Korean Intellectual Property Office on December 22, 2014, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
(a) Field of the Invention
A method of manufacturing molten iron using an improved charging method and an apparatus for manufacturing molten iron using the same are disclosed. More particularly, a method of manufacturing molten iron and an apparatus for manufacturing molten iron using the same, which control amounts of reduced materials and lump carbon materials charged into a melting gasification furnace and uniformize charging distribution, are disclosed.
(b) Description of the Related Art
In general, the steel industry is a core industry that supplies basic materials to various other industries such as the automobile industry, the shipbuilding industry, the consumer electronics industry, and the construction industry, and is one of the oldest industries that have been developed along with

the history of humanity. A steel mill, which plays a pivotal role in the steel industry, manufactures molten iron, that is, molten pig iron by using iron ore and coal as raw materials, manufactures steel from the molten iron, and then supplies the steel to respective demanders.
Currently, about 60 % of iron production in the whole world takes place through a blast furnace process that was developed in the 14th century. The blast furnace process is a method of manufacturing molten iron by putting coke, which is manufactured using sintered iron ore and free-burning coal as raw materials, into a blast furnace, blowing hot air into the blast furnace, and reducing iron ore to iron. However, there are problems in that the blast furnace process requires accessory facilities for manufacturing coke and sintered ore, and environmental pollution due to the accessory facilities is serious.
In order to solve the problems with the blast furnace process, there are great world wide efforts to develop a direct iron ore smelting reduction process. The direct iron ore smelting reduction process manufactures molten iron in a melting gasification furnace by directly using coal for general use as fuel and a reduction agent, and directly using ore as an iron source. Here, oxygen is blown into the melting gasification furnace through a plurality of tuyeres installed in an outer wall of the melting gasification furnace, thereby combusting a coal packed bed in the melting gasification furnace. The coal packed bed is formed by coal such as lump coal or briquette coal that is charged into the melting gasification furnace. The oxygen blowing into the melting gasification furnace is converted into high-temperature reduction gas, and the reduction gas is sent to a reduction furnace to reduce and fire fine iron ore and auxiliary raw materials.

and is then discharged to the outside. Reduced iron reduced in the reduction furnace is conveyed to the melting gasification furnace and melted, and then is manufactured as molten iron.
An operation of the melting gasification furnace is greatly affected by distribution of coal and reduced iron that are charged into the melting gasification furnace and constitute a melting furnace bed. The distribution of coal and reduced iron, which constitute the melting furnace bed, is determined based on how to charge the coal and the reduced iron. In order to effectively charge the coal and the reduced iron while controlling distribution of the coal and the reduced iron, a distributor is installed in the melting gasification furnace. A method of charging the coal and the reduced iron is classified into a method of charging the coal and the reduced iron by using distributors that distribute the coal and the reduced iron, respectively, and a method of charging the coal and the reduced iron by using a single distributor after mixing the coal and the reduced iron.
In a case in which the coal and the reduced iron are charged into the melting gasification furnace by using the respective distributors, the coal and the reduced iron are input through different charging holes, and are charged by the distributors that are installed in the charging holes, respectively. Therefore, in order to control distribution of charging materials, devices capable of adjusting drop positions are required. A drop position of coal has been adjusted by a plurality of coal distributors, and a drop position of reduced iron has been adjusted by a plurality of reduced iron distributors. Accordingly, since the plurality of coal distributors and the plurality of reduced iron distributors are

required, there are problems in that the apparatus is complicated, and it is difficult to manage the apparatus. In addition, since the reduced iron is discharged through the plurality of reduced iron distributors, it is difficult to accurately meter an amount of reduced iron that is discharged. Accordingly, there are problems in that it is not possible to accurately know an amount of reduced iron charged into the melting gasification furnace, and it is difficult to control a production speed of molten iron.
In the case of the method of mixing and charging the coal and the reduced iron using a single distributor, the coal and the reduced iron are mixed in advance and charged by the single distributor, such that distribution thereof is controlled. However, even in this structure, there is a problem in that the coal is dropped farther from a center of the melting gasification furnace than the reduced iron, which makes distribution non-uniform.
In order to smoothly melt the reduced iron, it is necessary to stabilize a gas flow to allow a reduction reaction and heat exchange of the reduced iron to be sufficiently carried out, thereby allowing the reduced iron to be easily melted down. Gas is difficult to flow to a central portion of the melting gasification furnace because of a structure of the melting gasification furnace. Moreover, in a case in which a large amount of reduced iron is charged at the central portion, as the reduced iron is melted, a gap through which gas may flow is filled with the reduced iron, such that gas is more difficult to flow. Therefore, gas flow is unstable, and the reduced iron at the central portion is not heated, and as a result, the temperature is decreased. Accordingly, there are problems in that operating efficiency is decreased, and operating costs are increased.

In addition, for additional reduction and preheating in the reduction furnace, reduction gas generated in the melting gasification furnace is supplied to the reduction furnace through a bustle of the reduction furnace. However, in the related art, the bustle is installed not at a lower end of the reduction furnace, but above the reduced iron distributor so as to be spaced apart from the distributor. The reason is to minimize the reduction gas flowing directly into the reduction furnace through the reduced iron distributor. Since the bustle is moved upward from the lower end of the reduction furnace and then installed as described above, there are problems in that additional reduction by the reduction gas and efficiency of heat exchange deteriorate, and a size of the reduction furnace needs to be increased.
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. SUMMARY OF THE INVENTION
The present invention has been made in an effort to provide a method of manufacturing molten iron and an apparatus for manufacturing molten iron using the same, which may accurately meter an amount of reduced materials or coal that is charged into a melting gasification furnace.
The present invention has been made in an effort to provide a method of manufacturing molten iron and an apparatus for manufacturing molten iron using the same, which more uniform ize charging distribution of reduced materials and coal in a melting gasification furnace.

The present invention has been made in an effort to provide a method of manufacturing molten iron and an apparatus for manufacturing molten iron using the same, which block an inflow of reduction gas through a reduced iron distributor and improve a reduction rate by reduction gas.
The present invention has been made in an effort to provide a method of manufacturing molten iron and an apparatus for manufacturing molten iron using the same, which may minimize a size of a reduction furnace.
The present invention has been made in an effort to provide a method of manufacturing molten iron and an apparatus for manufacturing molten iron using the same, which may reduce manufacturing costs and maintenance costs by simplifying a structure of a distributor.
An exemplary embodiment of the present invention provides a method of manufacturing molten iron, including: preparing iron-containing materials; converting the iron-containing materials into reduced materials in a reduction furnace; preparing lump carbon materials which are supplied to a melting gasification furnace connected to the reduction furnace; measuring a weight of the reduced materials which are discharged from the reduction furnace and charged into the melting gasification furnace; charging the reduced materials and the lump carbon materials into the melting gasification furnace; and blowing oxygen into the melting gasification furnace and manufacturing molten iron.
The method may further include supplying reduction gas discharged from the melting gasification furnace into the reduction furnace.
The method may further include measuring a weight of the lump carbon materials to be charged before the charging of the lump carbon materials into

the melting gasification furnace.
The charging of the reduced materials and the lump carbon material may include dropping the reduced materials, and dropping the lump carbon materials from a lower height than a height from which the reduced materials are dropped.
The charging of the reduced materials and the lump carbon materials may alternately drop the reduced materials and the lump carbon materials and charge the reduced materials and the lump carbon materials into the melting gasification furnace.
In the charging of the reduced materials and the lump carbon materials, the reduced materials and the lump carbon materials may be mixed and charged into the melting gasification furnace.
Another exemplary embodiment of the present invention provides an apparatus for manufacturing molten iron, including: a reduction furnace which reduces iron-containing materials and converts the iron-containing materials into reduced materials; a melting gasification furnace which charges the reduced materials therein and manufactures molten iron; a reduced material hopper which is connected to the reduction furnace, accommodates the reduced materials, and measures a weight of the reduced materials that are charged into the melting gasification furnace; a reduced material discharge pipe which conveys the reduced materials from the reduced material hopper; a carbon material hopper which accommodates lump carbon materials; a carbon material discharge pipe which conveys the lump carbon materials from the carbon material hopper; a charging material conveying pipe which is connected to the reduced material discharge pipe and the carbon material discharge pipe, is

installed to the melting gasification furnace, and supplies the reduced materials and the lump carbon materials to the melting gasification furnace; and a distributor which is installed in the melting gasification furnace, is connected to the charging material conveying pipe, and charges the reduced materials and the lump carbon materials into the melting gasification furnace.
The carbon material hopper may measure a weight of the lump carbon materials that are charged into the melting gasification furnace.
The apparatus may further include a reduction gas supply pipe which supplies reduction gas discharged from the melting gasification furnace into a fluidized reduction furnace.
The carbon material discharge pipe may be disposed below the reduced material discharge pipe.
The charging material conveying pipe may extend in a vertical direction, the reduced material discharge pipe may be connected to an upper portion of the charging material conveying pipe, and the carbon material discharge pipe may be connected to a lower portion of the charging material conveying pipe at an interval from the reduced material discharge pipe.
The apparatus may have a structure in which the reduced materials from the reduced material hopper and the lump carbon materials from the carbon material hopper are mixed in the charging material conveying pipe and supplied to the distributor.
The apparatus may have a structure in which the reduced materials from the reduced material hopper and the lump carbon materials from the carbon material hopper are alternately conveyed to the charging material conveying

pipe and supplied to the distributor.
The number of reduced material hoppers may be at least two.
The number of carbon material hoppers may be at least two.
The reduction furnace may have an inclined surface so that a bottom surface of the reduction furnace becomes gradually narrower toward a tip, and a bustle for blowing reduction gas into the reduction furnace may be installed onto the inclined surface.
The reduction furnace may be a packed bed reduction furnace. The iron-containing materials may include iron ore. The apparatus may further include a hot compacted iron manufacturing apparatus which is connected to the packed bed reduction furnace and supplies the iron-containing materials to the packed bed reduction furnace, in which the iron-containing material is compacted by the hot compacted iron manufacturing apparatus.
The apparatus may further include a fluidized bed reduction furnace which is connected to the hot compacted iron manufacturing apparatus and supplies the iron-containing materials to the hot compacted iron manufacturing apparatus, in which the fluidized bed reduction furnace preliminarily reduces the iron-containing materials.
According to the present apparatus as described above, input amounts of the reduced materials and the lump carbon materials may be accurately metered, thereby more easily and accurately controlling a production speed of molten iron.
The lump carbon materials are dropped to a position closer to a central portion of the melting furnace in comparison with a position where the reduced

materials are dropped, such that a gas flow is further stabilized and efficiency of heat exchange is enhanced, thereby increasing productivity.
A reduction rate is improved by smoothly blowing the reduction gas into the reduction furnace by using the bustle, thereby improving efficiency of the reduction furnace and stabilizing operations.
The bustle may be positioned at a lower end of the reduction furnace, thereby minimizing a size of the reduction furnace.
Manufacturing costs and maintenance costs are reduced by simplifying a structure of a reduced material distributor.
The reduced materials and the coal may be charged into the melting gasification furnace after mixing the reduced materials and the coal or the reduced materials and the coal may be alternately charged into the melting gasification furnace, as necessary. BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view illustrating a molten iron manufacturing apparatus according to a first exemplary embodiment of the present invention.
FIG. 2 is a schematic view illustrating a molten iron manufacturing apparatus according to a second exemplary embodiment of the present invention.
FIG. 3 is a schematic view illustrating a structure for charging reduced iron and lump carbon materials for the molten iron manufacturing apparatus in FIGS. 1 and 2.
FIG. 4 is a schematic view illustrating a state in which the reduced iron and the lump carbon materials are charged into a melting gasification furnace of

the molten iron manufacturing apparatus in FIGS. 1 and 2.
FIG. 5 is a schematic view illustrating another exemplary embodiment of a reduction furnace of the molten iron manufacturing apparatus in FIGS. 1 and 2. DETAILED DESCRIPTION OF THE EMBODIMENTS
The technical terms used herein are merely for the purpose of describing a specific exemplary embodiment, and are not intended to limit the present invention. Singular expressions used herein include plural expressions unless they have definitely opposite meanings. The terms "comprises" and/or "comprising" used in the specification specify particular features, regions, integers, steps, operations, elements, and components, but do not preclude the presence or addition of other particular features, regions integers, steps, operations, elements, components, and/or groups thereof.
Hereinafter, an exemplary embodiment of the present disclosure will be described with reference to the accompanying drawings so that those skilled in the technical field to which the present disclosure pertains may carry out the exemplary embodiment. It can be easily understood by those skilled in the art to which the present invention pertains that the following exemplary embodiments may be modified to various forms without departing from the concept and the scope of the present invention. Accordingly, 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.
An iron-containing material may be iron itself, or all materials including iron. For example, the iron-containing material may further include an auxiliary

raw material. The iron-containing material includes iron ore. The iron may be pure iron, an iron oxide, or reduced iron. A grain size of the iron-containing material is not limited. Therefore, the iron-containing material may include a pellet, fine grain iron ore, coarse grain iron ore, hot compacted iron, and the like.
The reduction furnace means a manufacturing apparatus for reducing the iron-containing material. The reduction furnace includes a fluidized bed reduction furnace or a packed bed reduction furnace.
FIG. 1 schematically illustrates a molten iron manufacturing apparatus according to a first exemplary embodiment of the present invention. A molten iron manufacturing apparatus 100 illustrated in FIG. 1 is merely for exemplifying the present invention, and the present invention is not limited thereto. Therefore, the molten iron manufacturing apparatus 100 may be modified to other forms.
The molten iron manufacturing apparatus 100 illustrated in FIG. 1 includes a reduction furnace 20 and a melting gasification furnace 40. Other devices may be included in addition to the furnaces, as necessary. In order to reduce iron-containing materials, the iron-containing materials are charged into the reduction furnace 20. The iron-containing materials to be charged into the reduction furnace 20 are dried and prepared in advance. Powdered raw materials may be mixed therein as necessary. The iron-containing material is converted into a reduced material in the reduction furnace 20. The reduction furnace 20 is a packed bed reduction furnace having a packed bed formed therein, and reduces and fires the iron-containing materials by being supplied with reduction gas from the melting gasification furnace 40. Therefore, the

iron-containing material is converted into the reduced material while passing through the packed bed.
The melting gasification furnace 40 manufactures the reduced material as molten iron. In order to form a coal packed bed in the melting gasification furnace 40, lump carbon materials are prepared and then charged into the melting gasification furnace. For example, the lump carbon material may be lump coal or briquette coal. The briquette coal is manufactured by pressing powdered coal. In addition, coke may be charged as necessary. The melting gasification furnace 40 has a structure in which a plurality of tuyeres are formed in an outer wall thereof. Oxygen is blown into the melting gasification furnace 40 through the tuyeres.
The reduced materials and the lump carbon materials are charged into the melting gasification furnace 40 after accurately metering an amount of the reduced materials and the lump carbon materials which are input from the outside of the melting gasification furnace 40. Therefore, it is possible to accurately check an amount of reduced materials that are charged into the melting gasification furnace 40. Accordingly, it is possible to accurately and easily adjust a production speed of molten iron produced in the melting gasification furnace.
To this end, as illustrated in FIG. 1, the present molten iron manufacturing apparatus includes a reduced material hopper 50 and a carbon material hopper 60 that accurately meter charging amounts of reduced materials and lump carbon materials that are charged into the melting gasification furnace 40.

Hereinafter, a structure for charging the reduced materials and the lump carbon materials into the melting gasification furnace will be described in more detail.
The reduced materials reduced in the reduction furnace 20 are discharged from the reduction furnace through a reduced material discharge screw 52. A plurality of reduced material discharge screws 52 may be provided, and the reduced materials, which pass through each of the reduced material discharge screws 52, are charged into the reduced material hopper 50 through reduced material conveying pipes 54.
The reduced material hopper 50 measures a weight of the reduced materials that are discharged from the reduction furnace 20 and charged into the reduced material hopper 50. For example, a load cell installed in the reduced material hopper 50 may be used to measure the weight of the reduced materials, but the present invention is not particularly limited thereto. Therefore, when the reduced materials are completely charged into the reduced material hopper, the load cell measures the weight of the reduced materials. Based on measured values from the load cell, it is possible to know an amount of reduced materials which will be supplied to the melting gasification furnace from the reduced material hopper later.
In the present exemplary embodiment, the two reduced material hoppers 50 are provided and disposed in parallel. While FIG. 1 illustrates the two reduced material hoppers 50, one or more than two reduced material hoppers may be used, and the number of reduced material hoppers is not particularly limited. In a case in which the two or more reduced material hoppers 50 are

provided, even if one reduced material hopper has a defect, the facility may be continuously operated through the remaining reduced material hoppers, thereby ensuring stability. In the present exemplary embodiment, the reduced material conveying pipes 54, which are connected to the reduced material discharge screws 52, diverge and are connected to the respective reduced material hoppers 50. The reduced materials, which are discharged through the reduced material discharge screws 52, may be sequentially or simultaneously charged into the respective reduced material hoppers 50 through the reduced material conveying pipes 54.
A reduced material discharge pipe 56, through which the reduced materials of which the weight is completely measured are conveyed, is installed at a lower end of the reduced material hopper 50. Each of the reduced material discharge pipes 56, which is connected to each of the reduced material hoppers 50, is connected to a charging material conveying pipe 70 that is installed at an upper end of the melting gasification furnace 40.
The lump carbon materials are conveyed by a lump carbon material conveying screw 62, and charged into the carbon material hopper 60 through a lump carbon material conveying pipe 64. In the present exemplary embodiment, the two carbon material hoppers 60 are provided and disposed in parallel. While FIG. 1 illustrates the two carbon material hoppers 60, one or more than two carbon material hoppers may be used, and the number of carbon material hoppers is not limited. In a case in which two or more carbon material hoppers are provided, even if one carbon material hopper has a defect, the facility may be continuously operated through the remaining carbon material

hoppers, thereby ensuring stability. In the present exemplary embodiment, the lump carbon material conveying pipe 64, which is connected to the lump carbon material conveying screw 62, diverges and is connected to each of the carbon material hoppers 60. The lump carbon materials, which are discharged through the lump carbon material conveying screw 62, may be sequentially or simultaneously charged into the respective carbon material hoppers 60 through the lump carbon material conveying pipe 64.
The present carbon material hopper 60 measures a weight of the lump carbon materials that are discharged from the lump carbon material conveying screw 62 and charged into the carbon material hopper 60. For example, a load cell installed in the carbon material hopper 60 may be used to measure the weight of the lump carbon materials, but the present invention is not particularly limited thereto. Therefore, when the lump carbon materials are completely charged into the carbon material hopper, the load cell measures the weight of the lump carbon materials. Based on measured values from the load cell, it is possible to know an amount of lump carbon materials, which will be supplied to the melting gasification furnace from the carbon material hopper later.
A carbon material discharge pipe 66, through which the lump carbon materials of which the weight is completely measured are conveyed, is installed at a lower end of the carbon material hopper 60. Each of the carbon material discharge pipes 66, which are connected to each of the carbon material hoppers 60, is connected to the charging material conveying pipe 70 that is installed at the upper end of the melting gasification furnace 40.
The upper end of the charging material conveying pipe 70 is connected

to the reduced material discharge pipe 56 and the carbon material discharge pipe 66. Therefore, the reduced materials, which are conveyed through the reduced material discharge pipes 56, and the lump carbon materials, which are conveyed through the carbon material discharge pipes 66, may be mixed in the charging material conveying pipe 70. A lower end of the charging material conveying pipe 70 is connected to the melting gasification furnace 40, such that the reduced materials and the lump carbon materials may be charged into the melting gasification furnace. A distributor 72, which inputs the charging materials to the melting gasification furnace 40 while turning, is installed at the lower end of the charging material conveying pipe 70. The distributor 72 uniformly distributes the reduced materials and the lump carbon materials, which are conveyed through the charging material conveying pipe 70, in all directions of the melting gasification furnace 40.
The molten iron manufacturing apparatus 100 according to the present exemplary embodiment may mix the reduced materials and the lump carbon materials through the charging material conveying pipe 70 as described above, and then charge the reduced materials and the lump carbon materials into the melting gasification furnace 40. Otherwise, the present molten iron manufacturing apparatus 100 may alternately charge the reduced materials and the lump carbon materials into the melting gasification furnace 40. That is, the molten iron manufacturing apparatus may mix and charge the reduced materials and the lump carbon materials, or may separately charge the reduced materials and the lump carbon materials. This is determined based on whether the reduced materials and the lump carbon materials are conveyed together, or are

alternately conveyed to the charging material conveying pipe 70. To this end, the reduced material discharge pipe 56 and the carbon material discharge pipe 66 may have, for example, a gate for opening and closing a pipeline or the conveying screw. Accordingly, by controlling the gates and the conveying screws installed in the reduced material discharge pipe 56 and the carbon material discharge pipe 66, it is possible to convey only the reduced materials or only the carbon materials, or convey the reduced materials and the carbon materials together to the charging material conveying pipe 70, thereby selectively changing the manner in which the reduced materials and the carbon materials are charged.
When the reduced materials and the lump carbon materials are conveyed to the charging material conveying pipe 70 through the reduced material discharge pipe 56 and the carbon material discharge pipe 66, the reduced materials and the lump carbon materials are mixed in the charging material conveying pipe 70, and then supplied to the distributor 72. Otherwise, when the conveyance of the reduced materials through the reduced material discharge pipe 56 is blocked and only the conveyance of the lump carbon materials through the carbon material discharge pipe 66 is performed, only the lump carbon materials are supplied to the charging material conveying pipe 70. Therefore, the distributor 72 charges only the lump carbon materials into the melting gasification furnace. When the lump carbon materials are completely charged according to a set value, the conveyance of the lump carbon materials through the carbon material discharge pipe 66 is blocked, and the reduced materials are conveyed through the reduced material discharge pipe 56.

Accordingly, only the reduced materials are supplied to the charging material conveying pipe 70, such that the distributor 72 charges only the reduced materials into the melting gasification furnace. As described above, by controlling the reduced material discharge pipe 56 and the carbon material discharge pipe 66, a method of charging the reduced materials into the melting gasification furnace through the discharge pipe is changed.
As described above, the reduced materials charged into the melting gasification furnace are melted while passing through the coal packed bed. A combustion zone is formed by oxygen blown into the melting gasification furnace 40, such that the reduced materials are melted and molten iron is manufactured. A tap hole is formed at a lower side of the melting gasification furnace 40, thereby discharging the molten iron and slag to the outside.
Reduction gas is produced from the coal packed bed formed in the melting gasification furnace 40. The reduction gas discharged from the melting gasification furnace 40 is supplied to the reduction furnace 20 through a reduction gas supply pipe 42. A bustle 44, which is connected to the reduction gas supply pipe 42, is installed to the reduction furnace, such that the reduction gas is blown into the reduction furnace 20 through the bustle 44. Therefore, fine iron ore and auxiliary raw materials may be reduced and fired by the reduction gas.
Here, the present molten iron manufacturing apparatus has the reduced material hopper 50 as described above, thereby preventing the reduction gas in the melting gasification furnace from flowing directly into the reduction furnace 20 through the reduced material conveying pipe 54. Therefore, the bustle 44

may be maximally moved toward a lower end of the reduction furnace 20, and installed to be close to the reduced material discharge screw 52. Accordingly, it is possible to minimize a size of the reduction furnace 20, and to maximize additional reduction by the reduction gas and efficiency of heat exchange.
FIG. 2 illustrates a molten iron manufacturing apparatus according to a second exemplary embodiment of the present invention. Because a molten iron manufacturing apparatus 200 illustrated in FIG. 2 is similar to the molten iron manufacturing apparatus 100 illustrated in FIG. 1, the same constituent elements are designated by the same reference numerals, and a detailed description thereof will be omitted.
As illustrated in FIG. 2, the molten iron manufacturing apparatus includes at least one fluidized bed reduction furnace 10, a hot compacted iron manufacturing apparatus 30, and a melting gasification furnace 40. In addition, the molten iron manufacturing apparatus may further include high-temperature equalizing and relief systems 20 and 38 for conveying hot compacted iron manufactured by the hot compacted iron manufacturing apparatus 30 to the melting gasification furnace 40. The high-temperature equalizing and relief system 20 at the lowermost end may be used as a reduction furnace. The high-temperature equalizing and relief system 38 pumps the hot compacted iron manufactured by the hot compacted iron manufacturing apparatus 30 to the melting gasification furnace 40. The hot compacted iron manufacturing apparatus 30 and the high-temperature equalizing and relief system 38 may be omitted as necessary.
The fluidized bed reduction furnace 10 allows iron ore, which is supplied

into the fluidized bed reduction furnace 10, to flow. As the iron ore, iron ore with a small grain size may be used, and the iron ore may be mixed with auxiliary raw materials and then used as necessary. A fluidized bed is formed in the fluidized bed reduction furnace 10 and reduces the iron ore. The fluidized bed reduction furnace 10 includes a first fluidized reduction furnace 12, a second fluidized reduction furnace 14, a third fluidized reduction furnace 16, and a fourth fluidized reduction furnace 18. While FIG. 2 illustrates four fluidized reduction furnaces, this is merely for exemplifying the present invention, and the present invention is not limited thereto. Therefore, three or more than four fluidized reduction furnaces may be used.
The first fluidized reduction furnace 12 preheats the iron ore using the reduction gas discharged from the second fluidized reduction furnace 14. The second fluidized reduction furnace 14 and the third fluidized reduction furnace 16 preliminarily reduce the preheated iron ore. Further, the fourth fluidized reduction furnace 18 finally reduces the preliminarily reduced iron ore, and converts the iron ore into reduced iron. The iron ore is reduced and heated while passing through the fluidized reduction furnaces. For this purpose, the reduction gas produced by the melting gasification furnace 40 is supplied to the fluidized reduction furnace through a reduction gas supply pipe 43. The reduced iron is manufactured as the hot compacted iron by the hot compacted iron manufacturing apparatus 30.
The hot compacted iron manufacturing apparatus 30 includes a charging hopper 32, a pair of roller 34, and a crusher 36. In addition, the hot compacted iron manufacturing apparatus 30 may further include other devices as necessary.

The charging hopper 32 stores the reduced iron. The pair of roller 34 compress the reduced iron charged from the charging hopper 32, and manufactures the hot compacted iron in the form of a strip. The hot compacted iron is crushed by the crusher 36, and conveyed to the high-temperature equalizing and relief system 38.
The high-temperature equalizing and relief system 38 adjusts pressure between both ends thereof, and charges the hot compacted iron into the packed bed reduction furnace 20. The hot compacted iron is converted into the reduced material by the packed bed reduction furnace 20.
The aforementioned reduced materials are charged into the melting gasification furnace 40. Meanwhile, as a heat source for melting the iron-containing material, lump carbon materials containing volatile substances are charged into the melting gasification furnace 40. When the reduced iron is melted in the melting gasification furnace by combustion of the lump carbon materials, the molten iron is manufactured and discharged to the outside.
Here, the reduced materials and the lump carbon materials are charged into the melting gasification furnace 40 after accurately metering an amount of the reduced materials and the lump carbon materials which are input from the outside of the melting gasification furnace 40. Therefore, it is possible to accurately check an amount of reduced materials that are charged into the melting gasification furnace 40. Accordingly, it is possible to accurately and easily adjust a production speed of molten iron produced in the melting gasification furnace.
To this end, as illustrated in FIG. 2, the present molten iron

manufacturing apparatus includes a reduced material hopper 50 and a carbon material hopper 60 that accurately meter charging amounts of reduced materials and lump carbon materials that are charged into the melting gasification furnace. Because a structure in FIG. 2, in which the reduced material hopper 50 and the carbon material hopper 60 are included, and the reduced materials and the lump carbon materials are charged into the melting gasification furnace from the packed bed reduction furnace, is the same as the structure for charging the reduced materials and the lump carbon materials as illustrated in FIG. 1, a detailed description thereof will be omitted hereinafter.
FIG. 3 illustrates yet another exemplary embodiment in which in the molten iron manufacturing apparatus in FIGS. 1 and 2, the reduced materials and the lump carbon materials are charged into the melting gasification furnace.
FIG. 3 illustrates a part for charging the charging materials including the reduced materials and the lump carbon materials into the melting gasification furnace, and this part is identically applied to the exemplary embodiments illustrated in FIGS. 1 and 2.
The charging method illustrated in FIG. 3 is merely for exemplifying the present invention, and the present invention is not limited thereto. Therefore, the reduced materials and the lump carbon materials may be charged by other methods from the outside of the melting gasification furnace.
The reduced materials reduced in the reduction furnace are stored in the reduced material hopper 50, and are charged into the melting gasification furnace 40 through the reduced material discharge pipe 56. The reduced material hopper 50 has a structure in which a reduced material storage bin 501,

an intermediate reduced material bin 502, and a reduced material charging bin 503 are substantially and sequentially connected. Therefore, the reduced materials sequentially pass through the reduced material storage bin 501, the intermediate reduced material bin 502, and the reduced material charging bin 503, and then are charged into the melting gasification furnace 20 through the reduced material discharge pipe 56.
The reduced materials passing through the reduced iron discharge pipe 56 are dropped through the charging material conveying pipe 70 and charged into the melting gasification furnace 20. The charging material conveying pipe 70 is installed in a vertical direction and thus may drop the reduced materials at a high speed, and position the reduced materials in the vicinity of the melting gasification furnace 20 via the distributor. The reduced materials are dropped from a relatively higher position compared to the lump carbon materials.
The lump carbon materials are stored in the carbon material hopper 60, and charged into the melting gasification furnace 40 through the carbon material discharge pipe 66. The carbon material hopper 60 has a structure in which a lump carbon material storage bin 601, an intermediate lump carbon material bin 602, and a lump carbon material charging bin 603 are substantially and sequentially connected. Therefore, the lump carbon materials sequentially pass through the lump carbon material storage bin 601, the intermediate lump carbon material bin 602, and the lump carbon material charging bin 603, are conveyed by the carbon material discharge pipe 66, and are then charged into the melting gasification furnace 40 after passing through the charging material conveying pipe 70. The reduced material discharge pipe 56 and the carbon

material discharge pipe 66 are connected to the charging material conveying pipe 70 while vertically intersecting the charging material conveying pipe 70, and as a result, the reduced materials and the lump carbon materials are easily mixed together, dropped, and charged.
In the present exemplary embodiment, the reduced material discharge pipe 56 and the carbon material discharge pipe 66 are connected to the charging material conveying pipe 70, which is vertically installed to the melting gasification furnace 40, with a difference in height between the reduced material discharge pipe 56 and the carbon material discharge pipe 66. That is, the reduced material discharge pipe 56 is connected to an upper portion of the charging material conveying pipe 70, and the carbon material discharge pipe 66 is connected to a lower portion of the charging material conveying pipe at an interval from the reduced material discharge pipe.
Accordingly, since the reduced material discharge pipe 56 is positioned above the carbon material discharge pipe 66, and the carbon material discharge pipe 66 is positioned relatively below the reduced material discharge pipe 56, the lump carbon materials are charged into the melting gasification furnace 40 at a lower speed than the reduced materials, and as a result, the lump carbon material may be distributed to a central portion of the melting gasification furnace 40.
That is, since there is a difference between a position where the reduced materials begin to be dropped through the reduced material discharge pipe 56 and a position where the lump carbon materials begin to be dropped through the carbon material discharge pipe 66, a large number of lump carbon materials may

be finally distributed to the central portion of the melting gasification furnace 40.
The distributor 72 finally charges the reduced materials and the lump carbon materials into the melting gasification furnace, and a point at which an object discharged from the rotating distributor is finally dropped is determined based on a tilting angle of the distributor and a speed at which the reduced materials and the lump carbon materials are discharged from the distributor. Since the distributor 72 is installed at a center of the melting gasification furnace and has the same tilting angle, the lump carbon materials need to be discharged from the distributor at a lower speed than the reduced materials so that the lump carbon materials are dropped to a position closer to the center of the melting gasification furnace in comparison with a position at which the reduced materials are dropped. In order to lower the speed at which the lump carbon materials are discharged from the distributor, kinetic energy of the lump carbon materials being discharged from the distributor needs to be low. Because potential energy is converted into kinetic energy when the lump carbon materials are freely dropped along the charging material conveying pipe that is vertically disposed, potential energy before the lump carbon materials are dropped needs to be low to lower kinetic energy.
As described above, in the present exemplary embodiment, the position of the carbon material discharge pipe is relatively lower than the position of the reduced material discharge pipe, such that a position where the reduced materials are dropped is relatively high, and a position where the lump carbon materials are dropped is relatively low. Therefore, since the lump carbon materials begin to be dropped from a lower position than the reduced materials.

potential energy of the lump carbon materials is relatively lower than potential energy of the reduced materials.
Accordingly, as illustrated in FIG. 4, since potential energy of the lump carbon materials is relatively low, the lump carbon materials, which are dropped through the distributor, are finally dropped closer to the center of the melting gasification furnace than the reduced materials. That is, since potential energy is converted into kinetic energy as the lump carbon materials begin to be dropped from a lower position and accelerate, a speed at which the lump carbon materials are discharged from the distributor becomes relatively slower than a speed of the reduced materials, and as a result, the lump carbon materials are dropped to a position closer to the center of the melting gasification furnace.
By controlling charging distribution of the lump carbon materials and the reduced materials as described above, a larger number of lump carbon materials are distributed to the central portion of the melting gasification furnace. Since a larger number of lump carbon materials are distributed to the center of the melting gasification furnace, gas flow is stabilized, and efficiency of heat exchange is enhanced, such that productivity is improved and operating costs are reduced.
Meanwhile, FIG. 5 illustrates yet another exemplary embodiment of the reduction furnace of the molten iron manufacturing apparatus illustrated in FIGS. 1 and 2.
As illustrated in FIG. 5, the reduction furnace 20 has an inclined surface 80 so that a lower bottom surface of the reduction furnace 20 becomes gradually narrow toward a tip. The reduced material discharge screw 52 is installed at a

lowermost end of the reduction furnace 20. Therefore, the reduced materials are discharged through the single reduced material discharge screw 52. The bustle 44 for blowing the reduction gas into the reduction furnace is installed onto the inclined surface 80 at the bottom of the reduction furnace.
The reduction furnace according to the present exemplary embodiment discharges the reduced materials by using only the single reduced material discharge screw 52, and as a result, it is possible to reduce the number of reduced material discharge screws to be installed, thereby greatly reducing cost required to manufacture and maintain the facility. In addition, the bustle 44 is installed onto the inclined surface 80, thereby further enhancing additional reduction by the reduction gas and efficiency of heat exchange.
While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be 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.
10: Fluidized bed reduction furnace
20: Packed bed reduction furnace
30: Hot compacted iron manufacturing apparatus
40: Melting gasification furnace
42: Supply pipe 44: Bustle
50: Reduced material hopper
52: Reduced material discharge screw

54: Reduced material conveying pipe
56: Reduced material discharge pipe
60: Carbon material hopper
62: Lump carbon material conveying screw
64: Lump carbon material conveying pipe
66: Lump carbon material discharge pipe
70: Charging material conveying pipe
72: Distributor
80: Inclined surface

WHAT IS CLAIMED IS:
1. An apparatus for manufacturing molten iron, comprising:
a reduction furnace which reduces iron-containing materials and converts the iron-containing materials into reduced materials;
a melting gasification furnace which charges the reduced materials thereinto and manufactures molten iron;
a reduced material hopper which is connected to the reduction furnace, accommodates the reduced materials, and measures a weight of the reduced materials that are charged into the melting gasification furnace;
a reduced material discharge pipe which conveys the reduced materials from the reduced material hopper;
a carbon material hopper which accommodates lump carbon materials;
a carbon material discharge pipe which conveys the lump carbon materials from the carbon material hopper;
a charging material conveying pipe which is connected to the reduced material discharge pipe and the carbon material discharge pipe, is installed to the melting gasification furnace, and supplies the reduced materials and the lump carbon materials to the melting gasification furnace; and
a distributor which is installed in the melting gasification furnace, is connected to the charging material conveying pipe, and charges the reduced materials and the lump carbon materials into the melting gasification furnace.
2. The apparatus of claim 1, wherein the carbon material discharge

pipe is disposed below the reduced material discharge pipe.
3. The apparatus of claim 2, wherein the charging material conveying pipe extends in a vertical direction, the reduced material discharge pipe is connected to an upper portion of the charging material conveying pipe, and the carbon material discharge pipe is connected to a lower portion of the charging material conveying pipe at an interval from the reduced material discharge pipe.
4. The apparatus of claim 1, wherein the reduction furnace has an inclined surface so that a bottom of the reduction furnace becomes gradually narrower toward a tip, and the reduced material conveying pipe is connected to the tip of the bottom of the reduction furnace.
5. The apparatus of claim 4, wherein a bustle for blowing reduction gas into the reduction furnace is installed onto the inclined surface.
6. The apparatus of claim 5, further comprising a carbon material hopper which is connected to the lump carbon material conveying pipe and measures a weight of the lump carbon materials that are charged into the melting gasification furnace.
7. The apparatus of claim 6, wherein the number of reduced material hoppers or/and the number of carbon material hoppers is at least two.

8. The apparatus of claim 6, wherein the apparatus has a structure in which the reduced materials from the reduced material hopper and the lump carbon materials from the carbon material hopper are mixed in the charging material conveying pipe and supplied to the distributor.
9. The apparatus of claim 6, wherein the apparatus has a structure in which the reduced materials from the reduced material hopper and the lump carbon materials from the carbon material hopper are alternately conveyed to the charging material conveying pipe and supplied to the distributor.
10. The apparatus of claim 6, wherein the reduction furnace is a packed bed reduction furnace.
11. The apparatus of claim 10, further comprising a hot compacted iron manufacturing apparatus which is connected to the packed bed reduction furnace and supplies the iron-containing materials to the packed bed reduction furnace, wherein the iron-containing material is compacted by the hot compacted iron manufacturing apparatus.
12. The apparatus of claim 11, further comprising a fluidized bed reduction furnace which is connected to the hot compacted iron manufacturing apparatus and supplies the iron-containing materials to the hot compacted iron manufacturing apparatus, wherein the fluidized bed reduction furnace

preliminarily reduces the iron-containing materials.
13. A method of manufacturing molten iron, comprising:
preparing iron-containing materials;
converting the iron-containing materials into reduced materials in a reduction furnace;
preparing lump carbon materials which are supplied to a melting gasification furnace connected to the reduction furnace;
measuring a weight of the reduced materials which are discharged from the reduction furnace and charged into the melting gasification furnace;
charging the reduced materials and the lump carbon materials into the melting gasification furnace; and
blowing oxygen into the melting gasification furnace and manufacturing molten iron.
14. The method of claim 13, wherein the charging of the reduced materials and the lump carbon material includes dropping the reduced materials, and dropping the lump carbon materials from a lower height than a height from which the reduced materials are dropped.
15. The method of claim 13, further comprising supplying reduction gas discharged from the melting gasification furnace into the reduction furnace.
16. The method of claim 15, further comprising

measuring a weight of the lump carbon materials to be charged before the charging of the lump carbon materials into the melting gasification furnace.
17. The method of claim 16, wherein the charging of the reduced materials and the lump carbon materials includes preliminarily mixing the reduced materials and the lump carbon materials at the outside of the melting gasification furnace while dropping the reduced materials and the lump carbon materials.
18. The method of claim 16, wherein the charging of the reduced materials and the lump carbon materials alternately charges the reduced materials and the lump carbon materials.