JP2024000617A - Method for manufacturing sintered ore and apparatus for manufacturing sintered ore - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a sintered ore capable of obtaining a yield improvement effect of the sintered ore by using an air fuel supply device and an apparatus for manufacturing the sintered ore.

SOLUTION: A method for manufacturing sintered ore comprises: a granulation step in which sintering raw materials including iron-containing raw materials, carbon-containing raw materials, and CaO-containing raw materials are granulated using a granulator to form granulated particles; a charging layer forming step of charging grain particles into an endless movable pallet with a raw material supply device of a sintering machine to form a charging layer; a sintering step for igniting the carbon-containing raw material contained in a surface layer of the charging layer in an ignition furnace provided on a downstream side of the raw material supply device, and supplying gaseous fuel to the charging layer from a gaseous fuel supply device provided on the downstream side of the ignition furnace, and sucking air in the charging layer with a wind box provided below the pallet to ignite the carbon-containing raw material to form the charged layer into a sintered cake; and a crushing step for crushing the sintered cake into a sintering ore, wherein in the charging layer forming step, the charging layer is formed such that dry standard charging density of the charging layer is 1.80 dry-ton/m³ or less.

SELECTED DRAWING: Figure 1

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present invention relates to a method for producing sintered ore, which is a raw material for a blast furnace, and equipment for producing sintered ore.

Sintered ore, which is a raw material for blast furnaces, is generally made up of iron-containing raw materials such as iron ore powder, recovered powder in steel works, and sintered ore unsieved powder, CaO-containing raw materials such as limestone and dolomite, and charcoal such as coke powder and anthracite. It is manufactured using a Dwight Lloyd sintering machine (hereinafter referred to as "sintering machine"), which is an endless moving sintering machine, using a solid fuel as a sintering raw material.

The sintering raw material is charged into an endlessly movable pallet of the sintering machine, and a charging layer of the sintering raw material is formed. The thickness (height) of the charging layer is approximately 400 to 800 mm. Thereafter, the coal material in this charging layer is ignited by an ignition furnace installed above the charging layer. By suctioning air downward through a wind box installed under the pallet, the carbonaceous material in the charging layer is sequentially combusted. This combustion gradually progresses to the lower layer and forward as the pallet moves. The combustion heat generated at this time burns and melts the sintering raw material, producing a sintered cake. The obtained sintered cake is then crushed in an ore discharge section to become sintered ore.

In the above-mentioned sintering machine, it is important to improve the yield of sintered ore. As a technique for improving the strength and yield of sintered ore, Patent Document 1 discloses a sintering machine that is provided with a gaseous fuel supply device on the downstream side of an ignition furnace and supplies gaseous fuel from above the charging layer. ing. According to Patent Document 1, gaseous fuel is supplied into the charging layer by sucking air downward by a wind box, and the gaseous fuel is combusted, which tends to cause insufficient sintering due to lack of heat. It is said that not only the yield of sintered ore in the upper layer of the layer, but also the yield of sintered ore in the middle and lower layers of the charged layer will be increased.

Japanese Patent Application Publication No. 2010-107154

However, even if the sintering machine disclosed in Patent Document 1 is used, there is a problem that the yield of sintered ore may not be improved. An object of the present invention is to provide a method for producing sintered ore and equipment for producing sintered ore, which can improve the yield of sintered ore by using a gaseous fuel supply device.

The means for solving the above problems are as follows.
[1] A granulation step in which a sintering raw material containing an iron-containing raw material, a carbon-containing raw material, and a CaO-containing raw material is granulated into granulated particles using a granulator, and an endlessly movable a charging layer forming step of charging the granulated particles into a pallet to form a charging layer of the sintering raw material; The carbon-containing raw material is ignited, gaseous fuel is supplied to the charging layer from a gaseous fuel supply device provided downstream of the ignition furnace, and a wind box provided below the pallet is used to fill the charging layer. a sintering step in which the carbon-containing raw material is combusted by suctioning air to form a sintered cake from the charging layer; and a crushing step in which the sintered cake is crushed to form sintered ore. . A method for producing sintered ore, wherein in the charging layer forming step, the charging layer is formed so that the dry standard charging density of the charging layer is 1.80 dry-ton/m ³ or less.
[2] The method for producing sintered ore according to [1], further comprising a calculation step of calculating a dry reference charging density of the charging layer.
[3] When the dry standard charge density calculated in the calculation step is higher than 1.80 dry-ton/m ³ , the charge layer is formed by changing the conditions of the charge layer forming step. The method for producing sintered ore according to [2], wherein the charging density of the sintered ore is lowered.
[4] When the dry standard charging density calculated in the calculation step is higher than 1.80 dry-ton/m ³ , the conditions of the granulation step are changed so that the granulated particles are The method for producing sintered ore according to [2] or [3], wherein the width of the particle size distribution is narrowed.
[5] The method for producing sintered ore according to [4], wherein the amount of the CaO-containing raw material in the sintering raw material is increased.
[6] A granulator that granulates a sintered raw material containing an iron-containing raw material, a carbon-containing raw material, and a CaO-containing raw material to form granulated particles using a granulator; a raw material supply device that charges grain particles to form a charging layer of the sintering raw material; an ignition furnace that ignites the carbon-containing raw material contained in the surface layer of the charging layer; and a downstream side of the ignition furnace. a gaseous fuel supply device that is provided and supplies gaseous fuel to the charging layer; and a wind box that is provided below the pallet and sucks air in the charging layer; a sintering machine for sintering into a sintered cake; a crushing machine for crushing the sintered cake into sintered ore; and a control device for controlling the operations of the granulator, sintering machine, and crushing machine. , wherein the control device controls the sintering machine so that the dry standard charging density of the charging layer is 1.80 dry-ton/m ³ or less.
[7] The sintered ore manufacturing equipment according to [6], wherein the control device calculates a dry reference charging density of the charging layer.
[8] When the calculated dry standard charging density is higher than 1.80 dry-ton/m ³ , the control device changes the operating conditions of the sintering machine to increase the charging density of the charging layer. The sintered ore manufacturing equipment according to [7], which lowers the sintered ore production equipment.
[9] When the calculated dry standard charging density is higher than 1.80 dry-ton/m ³ , the control device changes the granulation conditions of the granulator to adjust the particle size distribution of the granulated particles. The sintered ore manufacturing equipment according to [7] or [8], which narrows the distribution width of the sintered ore.

By carrying out the method for producing sintered ore according to the present invention, a charging layer with a charging density of 1.80 dry-ton/m3 or less is formed. yield improvement effect can be obtained.

FIG. 1 is a schematic diagram showing a sintered ore manufacturing facility in which the sintered ore manufacturing method according to the present embodiment can be carried out. FIG. 2 is a schematic cross-sectional view of the sintering test apparatus used in the sintering test. FIG. 3 is a graph showing the relationship between the dry standard charging density of the charging layer and the LNG yield improvement effect. FIG. 4 is a schematic diagram showing the state of granulated particles in the charging layer. FIG. 5 is a graph showing the relationship between the high temperature retention time of 1200° C. or higher and the LNG yield improvement effect. FIG. 6 is a graph showing the relationship between dry standard charging density and high temperature retention time of 1200° C. or higher.

Hereinafter, the present invention will be explained through embodiments of the present invention. FIG. 1 is a schematic diagram showing a sintered ore manufacturing facility in which the sintered ore manufacturing method according to the present embodiment can be carried out. The sintered ore manufacturing facility 10 includes a granulator 16, a sintering machine 20, a crusher 30, and a control device 40.

The granulator 16 granulates the sintered raw material 12 containing an iron-containing raw material, a carbon-containing raw material, and a CaO-containing raw material to form granulated particles 18 . When the granulator 16 granulates the granulated particles 18, granulating water 14 is added to the sintering raw material 12. This process becomes the granulation step. Granulated particles 18 granulated by the granulator 16 are conveyed to a sintering machine 20. Note that the iron-containing raw material is, for example, iron ore or dust generated in a steel mill. The carbon-containing raw material is, for example, coke powder or anthracite coal. Further, the CaO-containing raw material is, for example, quicklime, limestone, or slag.

The sintering machine 20 is, for example, a Dwight Lloyd type sintering machine. The sintering machine 20 includes a raw material supply device 21 , a pallet 22 , a cutoff plate 23 , an ignition furnace 24 , a gaseous fuel supply device 25 , and a wind box 26 . The raw material supply device 21 charges the granulated particles 18 into a pallet 22 .

The pallet 22 is an endlessly movable pallet. When the granulated particles 18 are charged into the pallet 22 from the raw material supply device 21, a charged layer of the sintering raw material 12 is formed within the pallet 22. The cutoff plate 23 flattens the surface layer of the charged layer and adjusts the thickness of the charged layer to a preset target layer thickness. This process becomes the charge layer forming step.

The ignition furnace 24 is provided downstream of the raw material supply device 21 and ignites the carbon-containing raw material contained in the surface layer of the charging layer. The gaseous fuel supply device 25 supplies gaseous fuel to the surface side of the charging layer. For example, city gas (LNG) is supplied as the gaseous fuel. The gaseous fuel supplied from the gaseous fuel supply device 25 is not limited to city gas, but also includes blast furnace gas, coke oven gas, blast furnace/coke oven mixed gas, converter gas, natural gas, methane gas, ethane gas, propane gas, and shale gas. Any combustible gas selected from among these gases may be used.

The wind box 26 is provided below the pallet 22 and sucks air in the charging layer formed within the pallet 22 downward. When the air in the charge layer is sucked downward by the wind box 26, the combustion and melting zone in the charge layer moves below the charge layer. Further, by sucking the air in the charging layer downward, the gaseous fuel supplied from the gaseous fuel supply device 25 is introduced into the charging layer from the surface layer of the charging layer. As the pallet 22 moves, the combustion and molten zone within the charge layer moves downward, so that the sintered raw material 12 in the charge layer is sintered. By sintering the sintering raw material 12, a sintered cake is obtained. This process becomes the sintering step.

The crusher 30 crushes the sintered cake discharged from the sintering machine 20 to produce crushed sintered cakes. The crushed sintered cake is cooled and sized to produce sintered ore 32. This process becomes the crushing step.

The control device 40 is, for example, a general-purpose computer such as a workstation or a personal computer, which has a control section 41 and a storage section 42 . The control unit 41 is, for example, a CPU or the like, and controls the operations of the granulator 16, sintering machine 20, and crushing machine 30 by executing a program read from the storage unit 42. The storage unit 42 is, for example, an information recording medium such as an update-recordable flash memory, a built-in hard disk or a hard disk connected via a data communication terminal, a memory card, and a read/write device thereof. The storage unit 42 stores programs for the control unit 41 to execute various functions, data used in the programs, and the like.

The control unit 41 calculates the dry standard charging density of the charging layer formed in the pallet 22 of the sintering machine 20 . The control unit 41 obtains raw material conveyance speed data on a wet basis from the sintering machine 20, and calculates the raw material conveyance speed on a dry basis by subtracting the moisture content of the sintering raw material measured in advance. Furthermore, the control unit 41 calculates the dry standard charging density by dividing the dry standard raw material conveyance speed by the machine width of the sintering machine 20, the layer thickness of the charging layer, and the pallet speed. This process becomes a calculation step. The control unit 41 may display the calculated dry reference charging density.

When the calculated dry standard charging density is higher than 1.80 dry-ton/m ³ , the control unit 41 changes the granulation conditions of the granulator 16 and the operating conditions of the sintering machine 20 to reduce the charging layer. The charging density of the charging layer is lowered so that the dry standard charging density of the charging layer is 1.80 dry-ton/m ³ or less.

When changing the granulation conditions of the granulator 16, the control unit 41 changes the granulation conditions of the granulator 16 so that the distribution width of the particle size distribution of the granulated particles 18 becomes narrower. When the distribution width of the particle size distribution of the granulated particles 18 becomes narrower, the packing density of the granulated particles 18 charged into the pallet 22 becomes lower, so that the charging density of the charging layer decreases. The granulation conditions for narrowing the distribution width of the particle size distribution of the granulated particles 18 include changing the rotational speed of the granulator 16, the amount of sintering raw material 12 charged into the granulator 16, the amount of granulation water 14 added, etc. By conducting a granulation experiment and confirming the distribution width of the particle size distribution of the granulated particles 18, granulation conditions that narrow the distribution width of the particle size distribution of the granulated particles 18 can be determined.

Furthermore, the control unit 41 may increase the amount of the CaO-containing raw material mixed into the sintering raw material 12. Since CaO functions as a binder, it causes ungranulated powder that is difficult to be granulated to adhere to granulated particles, thereby reducing fine particles in the particle size distribution. Therefore, when the amount of the CaO-containing raw material is increased, the width of the particle size distribution of the granulated particles 18 becomes narrower. In addition, in the method for producing sintered ore according to the present embodiment, an increase in the amount of the CaO-containing raw material is also included in changing the granulation conditions.

Further, when changing the operating conditions of the sintering machine 20, the control unit 41 changes the opening degree of the charging gate of the raw material supply device 21 and the position of the cutoff plate 23. When changing the opening degree of the charging gate, the control unit 41 narrows the opening degree of the charging gate to reduce the amount of granulated particles 18 charged into the pallet 22. By reducing the amount of granulated particles 18 charged, the charging density of the charging layer is reduced.

Furthermore, when changing the position of the cutoff plate 23, the control unit 41 raises the position of the cutoff plate 23 to reduce the charging density of the charging layer. The cut-off plate 23 forces the granulated particles 18 downward to level the surface of the charge layer and adjust the thickness of the charge layer to a preset thickness. Therefore, by raising the position of the cut-off plate 23, the amount of granulated particles 18 pushed downward is reduced, so that the charging density of the charging layer is reduced.

Furthermore, when the raw material supply device 21 has a magnetic brake, the control unit 41 may strengthen the magnetic brake to reduce the amount of granulated particles 18 charged into the pallet 22. By reducing the amount of granulated particles 18 charged, the charging density of the charging layer is reduced.

In this way, the control unit 41 changes the granulation conditions of the granulator 16 and the operating conditions of the sintering machine 20 so that the dry standard charging density becomes 1.80 dry-ton/m ³ or less. Reduce the charging density of the inlet layer. Thereby, the effect of improving the yield of sintered ore by supplying gaseous fuel can be obtained.

Next, a sintering test that confirmed the relationship between the dry standard charging density of the charging layer, the yield improvement effect by gaseous fuel supply, and the high temperature retention time of 1200° C. or higher will be described. FIG. 2 is a schematic cross-sectional view of the sintering test apparatus used in the sintering test. The sintering test device 50 includes an ignition hood 51, a sintering pot 52, and a wind box 53. An ignition burner 54 is provided in the ignition hood 51 and ignites the coke powder contained in the surface layer of a charging layer 55 formed in the sintering pot 52.

The sintering pot 52 is a cylindrical container with a diameter of 300 mm and a height of 600 mm. Thermocouples 56 are provided in the upper, middle, and lower layers of the sintering pot 52 to measure the temperature at each location, and a grate bar 57 is provided at the lower end. Granulated particles of the sintering raw material were charged into the sintering pot 52 to form a charged layer 55 having a layer thickness of 600 mm. As a sintering raw material, granulated particles of a sintering raw material consisting of 89% by mass of iron ore, 11% by mass of lime, and 4.0% by mass of coke powder were used. A negative pressure of 10 kPa is sucked from the wind box 53, and air containing 0.4% by volume of city gas (LNG) is supplied from the ignition hood 51 for about 1/3 of the entire firing time from immediately after the ignition ends. Then, a sintering test was conducted in which the charge layer 55 of the sintering raw material was sintered. During the sintering test, three thermocouples 56 were used to measure the temperatures of the upper, middle, and lower layers of the charge layer 55. When city gas was supplied, coke powder equivalent to the calorific value of city gas was deducted from the sintering raw material. In addition, the yield is determined by dropping the sample after sintering from a height of 2 m four times, sieving the dropped sample with a 5 mm sieve, and calculating the mass of the sample on the sieve after sintering. Calculated by dividing by the sample mass.

FIG. 3 is a graph showing the relationship between the dry standard charging density of the charging layer and the LNG yield improvement effect. In FIG. 3, the horizontal axis is the dry standard charging density (dry-ton/m ³ ), and the vertical axis is the LNG yield improvement effect (point). Here, the LNG yield improvement effect is a value obtained by subtracting the yield of sintered ore sintered without supplying city gas from the yield of sintered ore sintered with city gas supplied. For example, if the yield of sintered ore increases from 80.0% by mass to 81.7% by mass by supplying city gas, the LNG yield improvement effect will be 1.7 points.

As shown in FIG. 3, the LNG yield improvement effect decreased as the dry standard charging density of the charging layer 55 increased. In particular, when the dry standard charging density was around 1.80 dry-ton/m ³ , there was a tendency for the LNG yield improvement effect to disappear. From this result, it was confirmed that as the dry standard charging density of the charging layer increases, the yield improvement effect by supplying gaseous fuel decreases. Furthermore, from FIG. 3, if the dry standard charging density is set to 1.70 dry-ton/ ^m3 or less, the LNG yield improvement effect increases, so the dry standard charging density of the charging layer is set to 1.70 dry-ton/m3 or less. /m ³ or less is preferable. Furthermore, if the dry standard charging density is set to 1.60 ry-ton/m ³ or less, the LNG yield improvement effect can be maximized, so the dry standard charging density of the charging layer is set to 1.60 ry-ton/m ³ It is more preferable to do the following.

FIG. 4 is a schematic diagram showing the state of granulated particles in the charging layer. FIG. 4(a) is a diagram showing the state of the granulated particles 18 in a charging layer with a low charging density, and FIG. 4(b) is a diagram showing the state of the granulated particles 18 in a charging layer with a high charging density. FIG. Unlike solid fuels such as coke breeze, gaseous fuel burns only in the voids that allow gas to pass through. When the charging density of the charging layer is low, as shown in FIG. 4(a), the combustion space for the gaseous fuel is wide and the local flow velocity of the gaseous fuel in the combustion space is slow. On the other hand, when the charging density of the charging layer is high, as shown in FIG. 4(b), the combustion space for the gaseous fuel is narrow and the local flow velocity of the gaseous fuel in the combustion space becomes high.

In other words, when the charging density of the charging layer is low, the gaseous fuel combustion space is wide and the local gaseous fuel flow velocity is slow, so the gaseous fuel is sufficiently combusted and the heat of combustion is used for granulation. A relatively long time for heat transfer to the particles 18 can be secured. As a result, the combustion heat of the gaseous fuel was transferred to the granulated particles 18, and the high temperature retention time of 1200° C. or higher was extended, which is considered to have the effect of improving the yield of sintered ore. On the other hand, when the charging density of the charging layer is high, the gaseous fuel combustion space is narrow and the local gaseous fuel flow velocity is high, so the gaseous fuel cannot be sufficiently combusted, and the combustion heat is not produced. It is not possible to secure enough time for heat to transfer to the particles. As a result, the combustion heat of the gaseous fuel could not be transferred to the granulated particles 18, and the high temperature retention time of 1200° C. or higher was not extended, making it difficult to exhibit the effect of improving the yield of sintered ore.

FIG. 5 is a graph showing the relationship between the high temperature retention time of 1200° C. or higher and the LNG yield improvement effect. In FIG. 5, the horizontal axis is the high temperature holding time (sec) of Δ1200° C. or more, and the vertical axis is the LNG yield improvement effect (point). Here, Δ1200℃ or higher high temperature retention time indicates the amount of change in high temperature retention time of 1200℃ or higher, "50" means that the high temperature retention time of 1200℃ or higher is extended by 50 seconds, and "-50 ” means that the high temperature holding time of 1200° C. or higher was shortened by 50 seconds.

As shown in FIG. 5, the LNG yield improvement effect increased as the high temperature holding time of 1200° C. or higher became longer. From this result, it was confirmed that the yield improvement effect by supplying gaseous fuel increases as the high temperature holding time of 1200° C. or higher becomes longer.

FIG. 6 is a graph showing the relationship between dry standard charging density and high temperature retention time of 1200° C. or higher. In FIG. 6, the horizontal axis is the dry standard charging density (dry-ton/m ³ ), and the vertical axis is the high temperature retention time (sec) of Δ1200° C. or more.

As shown in FIG. 6, when the dry standard charging density was higher than 1.80 dry-ton/m ³ , the high temperature holding time of 1200° C. or higher was hardly extended. On the other hand, it was confirmed that if the dry standard charging density is 1.80 dry-ton/m ³ or less, the high temperature holding time of 1200° C. or higher can be extended by supplying gaseous fuel. If the high-temperature holding time of 1200°C or higher can be extended, the strength of the sintered cake will improve, so the yield of sintered ore can be improved by setting the dry standard charging density of the charging layer to 1.80 dry-ton/ ^m3 or less. It can be seen that this can be achieved.

As described above, in the method for producing sintered ore according to the present embodiment, the charging layer is formed so that the dry standard charging density of the charging layer is 1.80 dry-ton/m ³ or less. By supplying gaseous fuel, a yield improvement effect can be obtained. Moreover, in the method for producing sintered ore according to the present embodiment, the dry standard charging density of the charging layer is calculated. By calculating the dry reference charging density of the charging layer in this manner, it becomes possible to determine whether or not the yield improvement effect can be obtained by supplying the gaseous fuel.

10 Sintered ore manufacturing equipment 12 Sintering raw material 14 Granulation water 16 Granulation machine 18 Granulation particles 20 Sintering machine 21 Raw material supply device 22 Pallet 23 Cut-off plate 24 Ignition furnace 25 Gaseous fuel supply device 26 Wind box 30 Crushing Machine 32 Sintered ore 40 Control device 41 Control section 42 Storage section 50 Sintering test device 51 Ignition hood 52 Sintering pot 53 Wind box 54 Ignition burner 55 Charging layer 56 Thermocouple 57 Great bar

Claims (9)

A granulation step of granulating a sintered raw material containing an iron-containing raw material, a carbon-containing raw material, and a CaO-containing raw material using a granulator to form granulated particles;
a charging layer forming step of charging the granulated particles into an endlessly movable pallet using a raw material supply device of a sintering machine to form a charging layer of the sintering raw material;
The carbon-containing raw material contained in the surface layer of the charging layer is ignited in an ignition furnace provided on the downstream side of the raw material supply device, and the gaseous fuel is charged from the gaseous fuel supply device provided on the downstream side of the ignition furnace. a sintering step in which the carbon-containing raw material is supplied to a layer and the carbon-containing raw material is combusted by sucking air in the charging layer with a wind box provided below the pallet to turn the charging layer into a sintered cake; ,
a crushing step of crushing the sintered cake to produce sintered ore;
has
In the charging layer forming step, the charging layer is formed so that the dry standard charging density of the charging layer is 1.80 dry-ton/m ³ or less. The method for producing sintered ore according to claim 1, further comprising a calculation step of calculating a dry reference charging density of the charging layer. When the dry standard charging density calculated in the calculation step is higher than 1.80 dry-ton/m ³ ,
The method for producing sintered ore according to claim 2, wherein the charging density of the charging layer to be formed is lowered by changing the conditions of the charging layer forming step. When the dry standard charging density calculated in the calculation step is higher than 1.80 dry-ton/m ³ ,
The method for producing sintered ore according to claim 2 or 3, wherein the conditions of the granulation step are changed to narrow the distribution width of the particle size distribution of the granulated particles to be granulated. The method for producing sintered ore according to claim 4, wherein the amount of the CaO-containing raw material added to the sintered raw material is increased. a granulator that granulates a sintered raw material containing an iron-containing raw material, a carbon-containing raw material, and a CaO-containing raw material to form granulated particles;
an endless movable pallet; a raw material supply device that charges the granulated particles into the pallet to form a charge layer of the sintering raw material; and ignites the carbon-containing raw material contained in the surface layer of the charge layer. a gaseous fuel supply device provided on the downstream side of the ignition furnace to supply gaseous fuel to the charging layer; and a window provided below the pallet to suck air in the charging layer. a sintering machine having a box for sintering the charging layer to form a sintered cake;
a crusher that crushes the sintered cake to produce sintered ore;
a control device that controls the operation of the granulator, sinterer, and crusher;
Equipped with
The control device controls the sintering machine so that the dry standard charging density of the charging layer is 1.80 dry-ton/m ³ or less. The sintered ore manufacturing equipment according to claim 6, wherein the control device calculates a dry reference charging density of the charging layer. If the calculated dry standard charge density is higher than 1.80 dry-ton/m ³ , the control device changes the operating conditions of the sintering machine to lower the charge density of the charge layer. The sintered ore manufacturing equipment according to claim 7. When the calculated dry standard charging density is higher than 1.80 dry-ton/m ³ , the control device changes the granulation conditions of the granulator to increase the distribution width of the particle size distribution of the granulated particles. The sintered ore manufacturing equipment according to claim 7 or 8, wherein the sintered ore manufacturing equipment is narrowed.

Images