CN116710577A - Method for charging raw materials into blast furnace - Google Patents
Method for charging raw materials into blast furnace Download PDFInfo
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- CN116710577A CN116710577A CN202280009877.XA CN202280009877A CN116710577A CN 116710577 A CN116710577 A CN 116710577A CN 202280009877 A CN202280009877 A CN 202280009877A CN 116710577 A CN116710577 A CN 116710577A
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- charging
- loading
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- 239000002994 raw material Substances 0.000 title claims abstract description 383
- 238000000034 method Methods 0.000 title claims abstract description 35
- 238000003860 storage Methods 0.000 claims abstract description 80
- 239000000463 material Substances 0.000 claims description 38
- 238000007599 discharging Methods 0.000 claims description 10
- 239000002245 particle Substances 0.000 abstract description 58
- 238000009826 distribution Methods 0.000 abstract description 23
- 230000001965 increasing effect Effects 0.000 abstract description 8
- 230000009467 reduction Effects 0.000 abstract description 6
- 238000009423 ventilation Methods 0.000 abstract description 4
- 208000028659 discharge Diseases 0.000 description 21
- 239000000571 coke Substances 0.000 description 15
- 238000005204 segregation Methods 0.000 description 14
- 238000005070 sampling Methods 0.000 description 9
- 238000009825 accumulation Methods 0.000 description 6
- 238000004088 simulation Methods 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 4
- 238000002474 experimental method Methods 0.000 description 4
- 238000009434 installation Methods 0.000 description 4
- 230000002093 peripheral effect Effects 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000005484 gravity Effects 0.000 description 3
- 230000008021 deposition Effects 0.000 description 2
- 238000011439 discrete element method Methods 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- -1 sinter Substances 0.000 description 2
- 239000011800 void material Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 235000019738 Limestone Nutrition 0.000 description 1
- 229910000805 Pig iron Inorganic materials 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000002146 bilateral effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000011362 coarse particle Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 239000006028 limestone Substances 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- 239000008188 pellet Substances 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/18—Bell-and-hopper arrangements
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B5/00—Making pig-iron in the blast furnace
- C21B5/008—Composition or distribution of the charge
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B5/00—Making pig-iron in the blast furnace
- C21B5/001—Injecting additional fuel or reducing agents
- C21B5/003—Injection of pulverulent coal
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21B—MANUFACTURE OF IRON OR STEEL
- C21B7/00—Blast furnaces
- C21B7/18—Bell-and-hopper arrangements
- C21B7/20—Bell-and-hopper arrangements with appliances for distributing the burden
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B1/00—Shaft or like vertical or substantially vertical furnaces
- F27B1/10—Details, accessories, or equipment peculiar to furnaces of these types
- F27B1/20—Arrangements of devices for charging
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27B—FURNACES, KILNS, OVENS, OR RETORTS IN GENERAL; OPEN SINTERING OR LIKE APPARATUS
- F27B3/00—Hearth-type furnaces, e.g. of reverberatory type; Tank furnaces
- F27B3/10—Details, accessories, or equipment peculiar to hearth-type furnaces
- F27B3/18—Arrangements of devices for charging
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/0025—Charging or loading melting furnaces with material in the solid state
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/0033—Charging; Discharging; Manipulation of charge charging of particulate material
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F27—FURNACES; KILNS; OVENS; RETORTS
- F27D—DETAILS OR ACCESSORIES OF FURNACES, KILNS, OVENS, OR RETORTS, IN SO FAR AS THEY ARE OF KINDS OCCURRING IN MORE THAN ONE KIND OF FURNACE
- F27D3/00—Charging; Discharging; Manipulation of charge
- F27D3/10—Charging directly from hoppers or shoots
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Blast Furnaces (AREA)
- Manufacture Of Iron (AREA)
Abstract
The invention provides a raw material charging method for a blast furnace, which realizes raw material particle size distribution in a furnace top bin suitable for positive tilting charging and negative tilting charging respectively, thereby increasing gas flow near the center of the blast furnace regardless of tilting mode and realizing further improvement of ventilation and reduction efficiency. A structure of a predetermined shape is provided in a raw material storage section of a furnace top bin, and a raw material collision position of the structure in the storage step is determined in accordance with a tilting manner in the loading step.
Description
Technical Field
The present invention relates to a method for charging a blast furnace with a raw material.
Background
In a blast furnace, the following operations are generally performed as in fig. 1: ore raw materials such as sinter, pellet, lump ore and the like and coke are alternately layered and filled from the upper part to form a ore layer and a coke layer, and high-temperature reducing gas flows upwards along the front end of a tuyere to obtain pig iron. In the following, the ore-based raw material and coke are collectively referred to as raw materials. In the figure, symbol 1 denotes a blast furnace, 2 denotes a tuyere, 3 denotes a ore layer, 4 denotes a coke layer, and 5 denotes a molten layer.
In such a blast furnace operation, the flow of the gas in the blast furnace affects the reduction efficiency of the ore-based raw material and the heat dissipation to the outside of the blast furnace. In general, in order to increase the reduction efficiency of the ore-based raw material and to reduce the amount of heat released to the outside of the blast furnace, it is desirable to have more gas flow near the center of the blast furnace.
The following 2 causes are mainly given as the causes.
(1) If the gas flow rate near the furnace wall of the blast furnace increases, the heat radiation amount to the outside of the blast furnace increases, and the energy efficiency decreases.
(2) In the lower part of the blast furnace, the ore raw material charged into the blast furnace is heated and reduced by a reducing gas to form a molten zone. The melting zone is a region where a rock-disk-like structure of molten layers and coke gaps, in which coke is present alone, are alternately present, in which particles of an ore-based raw material are melted with each other. The molten layer has a rock-disk structure in which the particles of the ore-based raw material are fused with each other, and thus the void ratio in the layer is extremely low. On the other hand, the void fraction of the coke gap is higher than that of the molten layer. Therefore, the gas flowing from the lower side in the vertical direction in the molten zone selectively flows through the coke slit. Here, if the amount of gas flowing near the center portion of the blast furnace increases, the height region of the molten zone expands. As a result, the number of coke slits in the molten zone increases, and the gas permeability increases.
For increasing the gas flow rate near the center of the blast furnace, it is effective to provide a large-particle-diameter raw material near the center in the radial direction of the blast furnace and a small-particle-diameter raw material near the furnace wall.
This is because the packed layer of large-sized particles has a smaller total specific surface area of particles packed therein than that of small-sized particles, that is, friction between the gas flowing in the packed layer and the particles is reduced, and the gas flow rate is increased.
Accordingly, various techniques have been proposed for increasing the gas flow rate near the center of the blast furnace by controlling the particle size distribution, the layer thickness, and the like, with respect to the ore layer and the coke layer formed in the blast furnace.
For example, patent document 1 proposes a method for charging a blast furnace with a silo and a bell-less charging device, which is a method for charging a blast furnace with a bell-less charging device having a rotating chute with a silo disposed in parallel on a furnace roof,
temporarily storing raw materials loaded into a blast furnace, and when the raw materials are loaded into the furnace through a furnace top bin discharged to a rotary chute arranged below the furnace top bin,
a movable plate which can be tilted freely is provided in the furnace top bin, the raw material loaded in the furnace top bin is collided with the movable plate, when the front end of the rotary chute tilts from the periphery to the center direction in the blast furnace, the movable plate is operated to make the falling direction of the raw material be the discharge port direction of the furnace top bin, the falling position of the raw material loaded in the furnace top bin is set to be right above the raw material discharge port, fine particles are accumulated near the discharge port and coarse particles are accumulated at a far position in the furnace top bin due to the accumulation characteristic of the raw material,
When the front end of the rotary chute is tilted from the center in the blast furnace to the surrounding direction, the movable plate is operated so that the falling direction of the raw material is the opposite direction to the discharge port of the furnace top bin, the falling position of the raw material charged into the furnace top bin is the side wall away from the discharge port, coarse raw material is collected near the discharge port, fine particles are collected away from the discharge port,
coarse grains are deposited in the central portion of the blast furnace. "
Prior art literature
Patent literature
Patent document 1: japanese patent No. 4591520
Disclosure of Invention
However, in the bell-less blast furnace shown in fig. 2, a top bin for temporarily storing the raw material charged into the blast furnace is provided at the top portion of the blast furnace. Then, the raw materials discharged from the top bin of the furnace by opening the flow regulating door are charged into the blast furnace through the collecting hopper and the rotary chute. At this time, the position of the tip in the radial direction of the rotating chute (hereinafter, also referred to as tilting) may be changed to adjust the position of the material falling in the radial direction of the blast furnace.
In the drawing, reference numeral 6 denotes a furnace top bin, 7 denotes a flow rate adjustment gate, 8 denotes a collection hopper, and 9 denotes a rotating chute.
That is, when charging a raw material into a blast furnace, the rotating chute rotates at a constant speed in the circumferential direction of the blast furnace with the shaft center of the blast furnace as a rotation shaft, and tilts at a constant interval. The tilting system is roughly classified into two types, and the case of tilting from the vicinity of the furnace wall of the blast furnace to the center of the blast furnace is called positive tilting loading, and the case of tilting from the center of the blast furnace to the vicinity of the furnace wall of the blast furnace is called negative tilting loading.
Among them, the anti-tilting charging has an effect of suppressing the inflow of the raw material into the central portion of the blast furnace after the raw material is charged and deposited into the blast furnace. Therefore, the material accumulation shape is easily stabilized, and the control of the material particle size distribution in the blast furnace is facilitated, as compared with the positive tilting charging.
As described above, from the viewpoint of increasing the gas flow rate in the vicinity of the central portion of the blast furnace, it is effective to provide a large-particle-diameter raw material in the vicinity of the central portion and a small-particle-diameter raw material in the vicinity of the furnace wall of the blast furnace in the radial direction of the blast furnace. In the present specification, auxiliary raw materials such as coke, ore (including agglomerated ore), and limestone, which are charged from the top of a blast furnace, are collectively referred to as raw materials. It is most preferable to provide a large-particle-diameter raw material in the center of the blast furnace for all of these raw materials, but it is also effective to provide a large-particle-diameter raw material in the center of any one or more of coke, ore, and a mixture of coke and ore. A batch of raw materials is typically stored in a top bin. Therefore, when the reverse tilting loading is performed, it is preferable to discharge a large amount of large-particle-size raw material in the top bin at the initial stage of raw material discharge from the top bin.
In this regard, the technology of patent document 1 intentionally segregates the raw material stored in the furnace roof bin by using a tiltable movable plate (hereinafter, also referred to as a segregation control plate) provided in the furnace roof bin. Thus, a preferred particle size distribution of the raw material in the furnace roof silo is achieved according to the tilting mode.
However, the technique of patent document 1 is not sufficient to achieve a raw material particle size distribution suitable for the counter-tilting loading in the top bin. That is, there is a case where a certain amount of large-particle-size raw material is mixed with the raw material discharged from the top bin from the middle to the end of the raw material discharge, and as a result, a certain amount of large-particle-size raw material may be mixed near the furnace wall of the blast furnace.
The present invention has been made in view of the above-described circumstances, and an object of the present invention is to provide a method for charging raw materials into a blast furnace, which can achieve a particle size distribution of raw materials in a top bin suitable for forward tilting charging and reverse tilting charging, respectively, thereby increasing a gas flow rate in the vicinity of a central portion of the blast furnace regardless of the tilting system, and further improving ventilation and reduction efficiency.
Accordingly, the inventors have conducted intensive studies to achieve the above object.
First, the inventors have examined the cause of insufficient achievement of the particle size distribution of the raw material in the furnace top bin suitable for the reverse tilting loading in some cases in the technique of patent document 1.
In general, from the viewpoint of downsizing a collection hopper that receives raw materials discharged from a top bin and from the viewpoint of enhancing grain size segregation in the bin, as shown in fig. 3, a raw material discharge port of the top bin is provided eccentrically from the center of a raw material storage unit to the shaft center side of a blast furnace on a horizontal plane (projection plane in the vertical direction). Fig. 3 is a schematic view showing the arrangement of each part of the furnace top bin when viewed from above in the vertical direction. In the figure, 6-1 is a raw material storage unit, and 6-2 is a raw material discharge port.
Here, the eccentric direction refers to a direction from the center of the raw material storage portion toward the center of the raw material discharge port on the horizontal plane, and a direction rotated 90 ° clockwise from the eccentric direction when viewed from above in the vertical direction is referred to as a 1 st direction, a direction rotated 180 ° is referred to as an opposite direction of the eccentric direction, and a direction rotated 270 ° is referred to as a 2 nd direction. The material discharge port of the top bin is provided eccentrically from the center of the material storage unit to the shaft center side of the blast furnace on the horizontal plane (projection plane in the vertical direction). Therefore, in a state where the top bin is provided at the top of the blast furnace, the eccentric direction is generally the same direction as the direction from the center of the raw material storage unit toward the shaft center of the blast furnace (hereinafter, also referred to as the shaft center direction of the blast furnace).
When the reverse tilting loading is performed according to the technique of patent document 1, as shown in fig. 4, the segregation control plate is operated so that the falling direction of the raw material is in the vicinity of a wall portion (hereinafter, also referred to as an eccentric opposite side wall portion) on the opposite side of the raw material discharge port of the top bin, that is, on the horizontal plane. Therefore, the raw material layer in the furnace top bin has a shape in which the raw material layer surface is inclined downward in the vertical direction (from the eccentric opposite side wall portion toward the wall portion on the eccentric direction side (hereinafter, also referred to as eccentric side wall portion)). In the figure, 6-3 is a segregation control plate.
When the particle size distribution of the raw material in the top bin and the discharge order of the raw material at the time of discharge from the top bin (discharge time of each raw material storage position in the top bin) in this case are calculated by numerical simulation called the discrete element method, as shown in fig. 5, more than half of the raw material with large particle size is accumulated in the vicinity of the raw material discharge port, that is, in the region of initial discharge of the raw material. However, it has been found that most of the large-particle-diameter raw material remaining is located near the wall portions (hereinafter also referred to as 1 st wall portion and 2 nd wall portion) on the 1 st and 2 nd sides, which are directions perpendicular to the eccentric direction of the top bin, that is, the region from the middle to the end of the raw material discharge. That is, it is found that when the charging is performed by reverse tilting, a certain amount of large-particle-diameter raw material is mixed in the vicinity of the furnace wall of the blast furnace.
Based on this, the inventors have further studied and found that the following are effective:
the falling positions of the raw materials loaded in the furnace top bin are dispersed not only near the eccentric opposite side wall part but also near the 1 st wall part and the 2 nd wall part,
therefore, as shown in fig. 6, the raw material layer in the top bin is inclined downward in the vertical direction from the 1 st wall portion and the 2 nd wall portion toward the raw material discharge port, in other words, the raw material layer is formed in a substantially mortar shape.
Moreover, it was found that the large-particle size raw material was more densely collected near the raw material discharge port.
The inventors consider the following reasons for the above reasons.
That is, the large-particle-diameter raw material tends to roll on the deposition surface more easily than the small-particle-diameter raw material. Accordingly, the material deposition layer inclined downward in the vertical direction from the 1 st wall portion and the 2 nd wall portion toward the material discharge port is formed by dispersing the falling position of the material charged into the top bin not only in the vicinity of the eccentric opposite side wall portion but also in the vicinity of the 1 st wall portion and the 2 nd wall portion. Then, the large-particle-diameter raw material gradually charged is rolled on the accumulation surface, while the small-particle-diameter raw material is accumulated at the falling position, so that the large-particle-diameter raw material is more densely accumulated near the raw material discharge port.
Then, based on the findings described above, the inventors studied a method of dispersing the falling position of the raw material charged into the top bin not only in the vicinity of the eccentric opposite side wall portion but also in the vicinity of the 1 st wall portion and the 2 nd wall portion, and found that the following is effective:
a structural body having a raw material collision surface is provided in the raw material storage section of the top bin,
the shape of the material collision surface is inclined downward from the top of the structure toward the end of the material collision surface in the opposite direction of the eccentricity, and in the 1 st and 2 nd directions perpendicular to the opposite direction of the eccentricity and the vertical direction, respectively.
Further, the inventors have further studied and found that: as shown in figure 8 of the drawings,
the shape of the material collision surface is inclined downward from the top of the structure toward the end of the material collision surface in the eccentric direction in addition to the 1 st and 2 nd directions in the eccentric opposite direction and in the direction perpendicular to the eccentric opposite direction and the vertical direction,
by determining the position of the collision of the raw material in the structure (provided inside the raw material storage unit of the top bin) according to the tilting system when the raw material is charged into the blast furnace, it is possible to realize the particle size distribution of the raw material in the top bin suitable for the forward tilting charging and the reverse tilting charging, respectively. In the figure, 6-4 is a structural body and 6-5 is a raw material collision surface.
The present invention has been completed based on the above findings and further repeated studies.
That is, the main constitution of the present invention is as follows.
1. A method for charging raw materials into a blast furnace,
the blast furnace is provided with a furnace top bin at the furnace top,
at least one of the furnace top bins is provided with:
a raw material storage part,
A raw material loading port for loading the raw material into the raw material storage part from above the raw material storage part, a structural body which is arranged in the raw material storage part and is provided with a raw material collision surface for collision with the raw material loaded from the raw material loading port, and
a raw material discharge port for discharging the raw material in the raw material storage portion from below the raw material storage portion,
the raw material discharge port is eccentrically provided from the center of the raw material storage unit in a horizontal plane,
the material collision surface of the structure is inclined downward from the top of the structure toward the end of the material collision surface in at least the eccentric direction, the opposite eccentric direction, and the 1 st and 2 nd directions perpendicular to the eccentric direction and the vertical direction,
the method for charging raw materials into a blast furnace further comprises the steps of:
a storage step of loading a raw material into the raw material storage unit from the raw material loading port of the top bin, causing the raw material to collide with the structure, and then storing the raw material in the raw material storage unit;
A charging step of discharging the raw material stored in the raw material storage unit from the raw material discharge port, and charging the discharged raw material into the blast furnace via a rotating chute of the blast furnace;
and determining a material collision position in the structure of the storing step according to a tilting manner of the loading step.
Here, the eccentric direction is a direction in which the raw material discharge port is eccentric from the center of the raw material storage portion on the horizontal plane. The opposite direction of the eccentricity is a direction opposite to the direction of the eccentricity on the same horizontal plane.
2. The method for charging a blast furnace raw material according to item 1, wherein inclination angles α and α' between a line segment connecting the top of the structure and the end of the raw material collision surface in the eccentric direction and the opposite eccentric direction and the horizontal direction are 25 to 45 °.
3. The method for charging a blast furnace raw material according to 1 or 2, wherein inclination angles β and γ between a line segment connecting the top of the structure and the end of the raw material collision surface in the 1 st direction and the 2 nd direction and a horizontal direction are 25 to 45 °.
4. The method for charging a blast furnace raw material according to any one of the above 1 to 3, wherein the top of the structure is located in a range of 0 to 0.6 in a dimensionless distance (R/R) from the center of the raw material storage unit on a horizontal plane.
Here, the dimensionless distance (R/R) refers to a value obtained by dividing a distance (R) from the center of the raw material reservoir section on a horizontal plane by an inner diameter (R) of the raw material reservoir section.
According to the present invention, it is possible to realize a raw material particle size distribution in a furnace top bin suitable for forward tilting loading and reverse tilting loading, respectively.
As a result, in the operation of the blast furnace, the gas flow rate in the vicinity of the center portion of the blast furnace can be increased in any tilting mode, and the ventilation and reduction efficiency can be further improved.
In addition, the present invention is excellent in operability and maintainability because it does not require strict control and a complex structure therefor.
Drawings
Fig. 1 is a schematic view showing a flow of gas in a blast furnace.
FIG. 2 is a schematic diagram showing the charging procedure of raw materials into a blast furnace.
Fig. 3 is a schematic view showing the arrangement of each part of the furnace top bin when viewed from above in the vertical direction.
Fig. 4 is a schematic diagram showing the material accumulation in the furnace top bin when the material is charged into the furnace top bin (assuming the reverse tilting charging) provided with the segregation control plate. (a) A schematic view when viewed from the eccentric direction, and (b) a perspective view.
Fig. 5 is a numerical simulation result of the particle size distribution of the raw material in the top bin when the raw material is charged into the top bin (assuming inverse tilting charging) provided with the segregation control plate, and the raw material discharge sequence (discharge time per raw material storage position in the top bin) when the raw material is discharged from the top bin.
Fig. 6 is a schematic view showing a material accumulation state in a furnace top bin, which is preferable when the reverse tilting loading is performed. (a) A schematic view when viewed from the eccentric direction, and (b) a perspective view.
Fig. 7 is a schematic view showing a material accumulation state in a furnace top bin which is preferable when the positive tilting loading is performed. (a) A schematic view when viewed from the eccentric direction, and (b) a perspective view.
Fig. 8 is a schematic diagram showing an example of the principle of storing a raw material in a top bin by a raw material charging method of a blast furnace according to an embodiment of the present invention.
Fig. 9 is a schematic view showing an example of the shape (outer peripheral shape) from the top of the structure to the end of the raw material collision surface.
Fig. 10 is a schematic view showing an example of a structure provided in the top bin.
Fig. 11 shows a schematic view of a preferred region at the top of the structure.
Fig. 12 is a numerical simulation result of the feed particle size distribution in the top bin and the feed discharge sequence (discharge time for each feed storage position in the top bin) at the time of discharging the feed from the top bin when feeding the feed to the top bin, assuming that the feed is reversely tilted under conditions 1 and 2.
Fig. 13 is a schematic view of an apparatus used in a model experiment.
Fig. 14 is a schematic view showing the particle size distribution (positive tilting loading) of the raw material obtained by the model experiment.
Fig. 15 is a schematic view showing the particle size distribution (anti-tilting loading) of the raw material obtained by the model experiment.
FIG. 16 is a schematic view showing the gist of adjusting the collision position of the raw material in the structure.
Detailed Description
The present invention will be described based on the following embodiments.
The method for charging a blast furnace with a raw material according to one embodiment of the present invention is performed in a blast furnace having 1 or more furnace top bins provided at the furnace top, and comprises the steps of:
a storage step of loading raw materials from a raw material loading port of a furnace top bin, causing the raw materials to collide with a structure of a predetermined shape, and then storing the raw materials in a raw material storage section of the furnace top bin;
and a loading step of discharging the raw material stored in the raw material storage unit of the top bin and loading the discharged raw material into the blast furnace through the rotating chute of the blast furnace.
Here, as shown in fig. 2, a furnace top bin is provided at the furnace top of the blast furnace, and temporarily stores raw materials charged into the blast furnace. The number of the furnace top bins provided at the top of the blast furnace is not particularly limited, and may be appropriately set according to the number of the types of raw materials and the volume required for the furnace top bins, and is usually 2 to 4.
The following describes a furnace top bin used in a method of charging raw materials into a blast furnace according to an embodiment of the present invention, and a storage step and a charging step of the method of charging raw materials into a blast furnace according to an embodiment of the present invention.
[ furnace roof silo ]
In the method for charging raw materials into a blast furnace according to one embodiment of the present invention, at least 1 of the furnace top bins uses a furnace top bin as shown in fig. 8, and the method includes:
a raw material storage part,
A raw material loading port (not shown) for loading the raw material into the raw material storage part from above the raw material storage part,
A structure body provided in the raw material storage part and having a raw material collision surface against which the raw material loaded from the raw material loading port collides, and
a raw material discharge port for discharging the raw material in the raw material storage portion to the lower side of the raw material storage portion.
The above-mentioned furnace top bins are preferably used for the furnace top bins provided at the furnace top of the blast furnace.
The terms upper, lower, upper and lower refer to the terms upper, lower, upper and lower in the vertical direction unless otherwise specified.
Here, the raw material charging port is provided at an upper portion of the raw material storage portion. The position of the raw material charging port on the horizontal plane is not particularly limited, but is generally located closer to the shaft center side of the blast furnace (in the same direction as the raw material discharging port) than the center position of the raw material storage portion.
The raw material charged from the raw material charging port falls to the raw material storage portion when the raw material collides with a raw material collision surface of a structure provided in the raw material storage portion, and is temporarily stored in the raw material storage portion. The raw materials temporarily stored in the raw material storage unit are usually in a batch. The raw material storage portion has a main body portion having a cylindrical shape, a truncated cone shape, or a combination thereof, and a reduced diameter portion having a diameter reduced downward.
The maximum diameter (outer diameter) of the furnace top bin is usually about 4000 to 5000mm, and the height of the furnace top bin is about 9000 to 13000 mm.
Then, as the blast furnace is operated, the flow rate regulating gate is opened, and the raw material is gradually discharged from the raw material discharge port at the lower end of the reduced diameter portion of the raw material storage portion by its own weight, and is charged into the blast furnace via the collecting hopper and the rotating chute.
As shown in fig. 3, the raw material discharge port is eccentric in the horizontal plane from the center of the raw material storage portion, and in general, the center-to-center distance (eccentric amount) between the raw material storage portion and the raw material discharge port in the horizontal direction: a is the inner diameter of the raw material storage section: r is 0.60 to 0.70 times of that of the base material. In addition, the inner diameter of the raw material discharge port: b is typically the inside diameter of the feedstock reservoir: r is 0.10 to 0.30 times of R. The center position and the inner diameter of the raw material storage portion are based on the height position at which the top portion of the structure is provided, which will be described later. The center position and the inner diameter of the raw material discharge port are based on the height position connected to the lower end of the raw material storage portion. This is also true thereafter.
In fig. 3, the example in which the horizontal cross section of the material storage portion is circular is described, and in other shapes, the center of the material storage portion is the center of gravity of the horizontal cross section having the largest area. In this case, the eccentric direction is a direction connecting the center of the raw material discharge port and the center of the raw material storage portion on the horizontal cross section (horizontal cross section of the maximum area) from the center of the raw material storage portion toward the center of the raw material discharge port, and R is 1/2 of the length of the raw material storage portion in the eccentric direction of the horizontal cross section.
In the method for charging a blast furnace with a raw material according to an embodiment of the present invention, the shape of the raw material collision surface of the structure is extremely important.
Specifically, it is important that the shape of the material collision surface as shown in fig. 8 be inclined downward from the top of the structure (material collision surface) toward the end of the material collision surface in at least the eccentric direction, the opposite eccentric direction, and the 1 st and 2 nd directions perpendicular to the eccentric and vertical directions.
That is, in the case of performing the reverse tilting loading, as shown in fig. 6, the falling position of the raw material loaded into the top bin is dispersed not only in the vicinity of the eccentric opposite side wall portion but also in the vicinity of the 1 st wall portion and the 2 nd wall portion. In this way, it is important to incline the shape of the raw material layer in the top bin downward in the vertical direction from the 1 st wall portion and the 2 nd wall portion toward the raw material discharge port, in other words, the shape of the raw material layer is substantially mortar-shaped. Thus, large-particle-diameter raw materials are more densely collected near the raw material discharge port. Therefore, it is important that the shape of the material collision surface (the outer peripheral shape of the vertical cross section) of the structure be inclined downward from the top of the structure toward the end of the material collision surface not only in the direction opposite to the eccentricity but also in the 1 st and 2 nd directions.
In the case of the forward tilting loading, as shown in fig. 7, the position where the raw material loaded into the top bin falls is dispersed not only in the vicinity of the eccentric side wall portion (i.e., in the vicinity of the raw material discharge port) but also in the vicinity of the 1 st wall portion and the 2 nd wall portion. In this way, it is important that the shape of the raw material layer in the furnace roof bin is inclined downward in the vertical direction not only from the eccentric side wall portion but also from the 1 st wall portion and the 2 nd wall portion toward the eccentric opposite side wall portion. Thereby, the large-particle-diameter raw material is collected at a position distant from the raw material discharge port. That is, the large-particle-size raw material is discharged at the end of the discharge of the top bin. Therefore, it is important that the shape of the material collision surface (the outer peripheral shape of the vertical cross section) of the structure be inclined downward in the eccentric direction from the top of the structure toward the end of the material collision surface.
Here, the inclination downward from the top of the structure toward the end of the raw material collision surface in the eccentric direction and the opposite eccentric direction means that the inclination downward from the top of the structure toward the end of the raw material collision surface is performed when the vertical cross section of the structure passing through the top position of the structure is viewed from the 1 st direction as shown in fig. 8. Similarly, the inclination downward from the top of the structure toward the end of the raw material collision surface in the 1 st and 2 nd directions means that the inclination downward from the top of the structure toward the end of the raw material collision surface in the 1 st and 2 nd directions is performed when the vertical cross section of the structure passing through the top position of the structure is viewed from the deflection direction as shown in fig. 8. Alternatively, the cross section of the structure along the 1 st and 2 nd directions is inclined downward from the highest position of the raw material collision surface toward the end.
The material collision surface is on the upper surface of the structure (the region of the structure when viewed from above). Therefore, the top of the structure is the highest position in the vertical direction of the raw material collision surface. Here, when there are a plurality of highest positions on the raw material collision surface, the highest position is at the top of the point farthest from the raw material discharge port in the eccentric direction. In addition, the member for fixing the structure and the like are also discharged outside the raw material collision surface. The material collision surface may be formed of 1 surface in succession, or may be formed of a plurality of surfaces.
Further, the inclination angles α and α' of the line segment connecting the top of the structure and the end of the raw material collision surface in the eccentric direction and the opposite eccentric direction with respect to the horizontal direction are preferably 25 to 45 °, respectively. More preferably, α and α' are each 40 to 43 °.
Further, the inclination angles β and γ of the line segment connecting the top of the structure and the end of the raw material collision surface in the 1 st and 2 nd directions and the horizontal direction are preferably 25 to 45 °, respectively. Beta and gamma are more preferably 40 to 43 deg., respectively.
Similarly, it is preferable that the shape from the top of the structure to the end of the raw material collision surface in the direction from the 1 st direction to the 2 nd direction (the direction from the eccentric direction to the 90 ° to 270 ° clockwise) is inclined downward from the top of the structure toward the end of the raw material collision surface. The preferred angles of inclination of the line segment connecting the top of the structure and the end of the raw material collision surface in these directions from the horizontal direction are also the same as the angles of inclination α, α', β, and γ described above.
The shape (outer peripheral shape) from the top of the structure to the end of the raw material collision surface in each vertical cross section of the structure need not be a constant gradient in any direction, and may be a shape in which the gradient varies variously, for example, a circular arc shape, and a shape in which the gradient varies stepwise, as shown in fig. 9.
The shape from the top of the structure to the end of the raw material collision surface in the direction from the 1 st direction to the 2 nd direction (the direction between 0 to 90 ° and 270 ° to 360 ° clockwise from the eccentric direction, but the 1 st direction and the 2 nd direction) is not particularly limited.
For example, the structure may be inclined downward from the top toward the end of the raw material collision surface in the same direction as the opposite direction of eccentricity, the 1 st direction, and the 2 nd direction. In this case, the shape of the structure is, for example, a conical shape, an oblique conical shape, an elliptical conical shape, a shape in which a cone is bonded to the upper part of a truncated cone (shape 1), a shape in which a bisected cone and a bisected elliptical cone are bonded to each other at a cutting surface (shape 2), a polygonal body such as a dome shape, a quadrangular pyramid, a hexagonal pyramid, or an octagon shape in which the collision surface of the raw material is spherical, a shape in which these shapes are cut in the vertical direction at arbitrary positions, or the like, as shown in fig. 10. The inside of the structure may be hollow, or no member may be provided on a surface other than the raw material collision surface, such as the bottom surface and the side surfaces. The shape described above also includes a shape that is changed by providing a member on the bottom surface or the like, as long as the area of the raw material collision surface does not change.
The length (distance between the ends of the raw material collision surface in the horizontal direction when the structure is viewed from the 1 st direction) a of the structure is preferably the inner diameter of the raw material reservoir portion: r is 0.4 to 0.8 times (see FIG. 8, which is the same for the width and height of the structure to be described later). The width (distance between the ends of the raw material collision surface in the horizontal direction when the structure is viewed from the eccentric direction) b of the structure is preferably the inner diameter of the raw material reservoir section: r is 0.4 to 0.8 times of R. The height of the structure (the distance from the lower end to the top of the raw material collision surface) is preferably the length of the structure: a is 0.47 to 1.0 times of a.
The shape of the structure may be symmetrical in the 1 st and 2 nd directions or asymmetrical.
Further, as shown in fig. 11, the top of the structure is preferably located at a non-dimensional distance (R/R) from the center of the raw material storage section in the range of 0 to 0.6 with respect to the installation position of the structure in the horizontal direction.
Here, the dimensionless distance (R/R) is a value obtained by dividing a distance (R) from the center of the raw material storage unit on a horizontal plane (projection plane in the vertical direction) by an inner diameter (R) of the raw material storage unit.
The installation position of the structure in the vertical direction is not particularly limited, but the non-vector height (H'/H) of the top of the structure is preferably in the range of 0.75 to 0.85.
Here, the dimensionless height (H'/H) refers to a distance (height) from a lower end of the furnace roof bin (height position of the raw material discharge port) to a top of the structure in the vertical direction: h' divided by the height of the top bin: h.
The above-described structure is preferably arranged in bilateral symmetry with respect to a plumb line passing through the center of the raw material storage unit when viewed from the eccentric direction. However, if the structure is inclined downward from the top to the ends in the 1 st and 2 nd directions, the structure may not be laterally symmetrical.
The material of the structure is not particularly limited, and a common steel material or the like may be used. The method of installing the structure is not particularly limited, and for example, the beam member may be fixed to the inner wall of the furnace top bin by a metal component, welding, or the like, and the structure may be fixed to the beam member by a metal component, welding, or the like. The above-described structure may further include a position adjustment mechanism for changing the position thereof, and a setting angle adjustment mechanism for changing the setting angle.
[ storage Process ]
The method for charging a blast furnace with a raw material according to one embodiment of the present invention is a method for charging a raw material into a raw material storage unit from a raw material charging port of a top bin, causing the raw material to collide with a structural body, and storing the raw material in the raw material storage unit.
It is important to determine (set) the material collision position in the structure in the present step according to a tilting system used in the loading step described later.
As described above, the preferable particle size distribution of the raw material in the top bin differs depending on the tilting mode. For example, when the raw material is reversely tilted, as shown in fig. 6, it is important to tilt the shape of the raw material layer in the top bin downward in the vertical direction not only from the eccentric opposite side wall portion but also from the 1 st wall portion and the 2 nd wall portion toward the raw material discharge port, in other words, to make the shape of the raw material layer substantially mortar-shaped (large-particle-diameter raw material is accumulated in the vicinity of the raw material discharge port). Therefore, in the case of the reverse tilting loading, the raw material collision position in the structure is set on the eccentric opposite direction side of the top of the structure.
On the other hand, when the furnace is tilted forward, it is important that the shape of the raw material layer in the furnace top bin be inclined downward in the vertical direction not only from the eccentric side wall portion but also from the 1 st wall portion and the 2 nd wall portion toward the eccentric opposite side wall portion, as shown in fig. 7. Therefore, in the case of positive tilting loading, the raw material collision position in the structure is set on the eccentric direction side of the top of the structure.
Here, the raw material collision position in the structure is determined to be the side of the opposite direction of the eccentricity or the side of the direction of the eccentricity based on the representative position in the opposite direction of the eccentricity of the raw material collision range in the structure.
That is, the collision position (range) of each particle of the raw material in the structure (raw material collision surface) viewed from above in the vertical direction is plotted with the top of the structure as the origin, the distance from the top of the structure in the direction opposite to the eccentricity as the horizontal axis (X axis), the distance from the top of the structure in the 1 st direction as the vertical axis (Y axis) (the distance to the direction opposite to the eccentricity and the 1 st direction is positive, and the distance to the direction eccentric and the 2 nd direction is negative). Then, the center of gravity position in the opposite direction of the eccentricity, that is, the average value of the opposite direction of the eccentricity (X-coordinate) in the drawing of the collision position of each particle is taken as the representative position in the opposite direction of the eccentricity of the raw material collision range in the structure (hereinafter, simply referred to as the representative position in the opposite direction of the eccentricity). Similarly, the center of gravity position in the 1 st direction, that is, the average value of the 1 st direction (Y coordinate) in the drawing of the collision positions of the particles is taken as a representative position in the 1 st direction of the raw material collision range in the structure (hereinafter, also simply referred to as a representative position in the 1 st direction).
For example, if the collision representative position in the opposite direction of eccentricity is a positive value (greater than 0), the raw material collision position in the structure is on the opposite direction side of eccentricity of the top of the structure, and if the collision representative position in the opposite direction of eccentricity is a negative value (less than 0), the raw material collision position in the structure is on the opposite direction side of eccentricity of the top of the structure.
In the case of reverse tilting, it is preferable that the eccentric portion is eccentricThe collision representative position in the opposite direction is a 1 /4～a 1 Range of/2. Here, a 1 Is the distance between the top of the structure and the end of the raw material collision surface in the direction opposite to the eccentricity (the distance between the top of the structure and the end of the raw material collision surface in the direction opposite to the eccentricity when the structure is viewed from the 1 st direction, refer to fig. 8).
In the case of positive tilting loading, it is preferable that the collision representative position in the opposite direction of eccentricity be-a 2 /2～－a 2 Range of/4. Here, a 2 Is the distance between the top of the structure and the end of the raw material collision surface in the eccentric direction (the distance between the top of the structure and the end of the raw material collision surface in the eccentric direction when the structure is viewed from the 1 st direction, refer to fig. 8).
The collision range in the 1 st direction of the raw material in the structure is not particularly limited, but it is preferable that the representative position in the 1 st direction of the collision range of the raw material in the structure (hereinafter, also referred to as collision representative position in the 1 st direction) is in the range of-b/10 to b/10. Particularly, the collision representative position in the 1 st direction is preferably 0.
The collision position of the raw material in the structure is adjusted so that 80% or more, preferably 90% or more of the number (number) of particles of the raw material falling from the raw material loading port collides with the structure (raw material collision surface) (that is, the ratio of collision of the structure with the raw material (= [ number of raw material colliding with the structure (raw material collision surface ]/[ number of raw material loaded into the furnace top bin ] ×100)) is 80% or more, preferably 90% or more. The collision ratio of the structure to the raw material may be 100%.
The position and angle of the raw material collision in the structure can be adjusted by, for example, providing a movable control plate 17 in the raw material passage from the receiving hopper to the raw material loading port of the top bin as shown in fig. 16, and changing the position and angle. Fig. 16 shows an example in which the raw material collision surface of the movable control plate 17 is fixed perpendicular to the horizontal plane, and the movable control plate 17 is moved in the direction opposite to the eccentric direction of the stove top bin 6, but the present invention is not limited thereto. For example, the position and angle of the raw material collision surface of the movable control plate 17 may be changed by changing the angle, so that the raw material collision position and collision angle in the structure can be adjusted more finely.
[ procedure for mounting ]
In the above-described storage step, the raw material stored in the raw material storage portion of the top bin is discharged from the raw material discharge port, and the discharged raw material is charged into the blast furnace through the rotating chute of the blast furnace by reverse tilting charging or forward tilting charging.
That is, in the case of performing the anti-tilting loading, the raw material is discharged from a top bin, which is a raw material particle size distribution suitable for the anti-tilting loading, and the discharged raw material is loaded into the blast furnace.
On the other hand, in the case of performing positive tilting charging, the raw material is discharged from a top bin as a raw material particle size distribution suitable for positive tilting charging, the discharged raw material is charged into a blast furnace,
as a result, when both the forward tilting loading and the reverse tilting loading are performed, the gas flow rate in the vicinity of the center portion of the blast furnace is increased, and the ventilation and the reduction efficiency are improved.
Conditions other than the above are not particularly limited. The preparation method is carried out according to a conventional method.
Examples
The furnace top bin was modeled according to the following conditions 1 and 2, and the particle size distribution of the raw material in the furnace top bin when the raw material was charged into the furnace top bin and the raw material discharge sequence (discharge time for each raw material storage position in the furnace top bin) when the raw material was discharged from the furnace top bin were calculated by the discrete element method.
Condition 1 (inventive example)
[ shape of Structure disposed in roof silo ]
Inclination angle: α=42°, α' =42°, β=42°, γ=42°
Width: a=r×0.5, length: b=r×0.5, height: h=a×0.5
[ position of installation of Structure in roof silo ]
Position of top of structure: a position along the eccentric direction R/r=0.53 from the center position of the raw material reservoir portion
Set height at top of structure: h'/h=0.82
[ raw material collision position in Structure in roof silo ]
At the time of positive tilting loading
Eccentric direction side
(collision representative position of opposite direction of eccentricity: -a) 2 Collision representative position in 1 st direction: 0. raw material collision ratio: 100%)
At the time of reverse tilting loading
Eccentric opposite direction side
(collision representative position of eccentric opposite direction: a) 1 Collision representative position in the 1 st direction/2: 0. raw material collision ratio: 100%)
Condition 2 (comparative example)
[ shape of Structure disposed in roof silo ]
Plate-like (segregation control panel mentioned in patent document 1)
Inclination angle:
α=80°, β=0°, γ=0° during positive tilting loading
α=155° (α' =25°), β=0°, γ=0° at the time of anti-tilting loading
Width: r×0.31, length: r×1.0, thickness: 160mm
[ position of installation of Structure in roof silo ]
Center position of segregation control panel: a position along the eccentric direction R/r=0.37 from the center position of the raw material reservoir portion
Setting height of center position of segregation control plate: h'/h=0.42
[ raw material collision position in Structure in roof silo ]
Approximately central position of the segregation control plate, raw material collision ratio: 100 percent of
(Forward and reverse tilting loads are the same)
The structures of conditions 1 and 2 are each arranged symmetrically with respect to a plumb line passing through the center of the raw material storage unit when viewed from the eccentric direction.
The shapes of the raw material storage portion, the raw material loading port, and the raw material discharge port of the top bin were modeled based on the actual machine under the same conditions as those of conditions 1 and 2 (r=2350 mm, h=12000 mm, a center-to-center distance (eccentricity) between the raw material storage portion and the raw material discharge port: a=r×0.64, and an inner diameter of the raw material discharge port: b=r×0.35).
The raw material charging conditions were the same as those in conditions 1 and 2. Specifically, the raw material mentioned here means ore, and the raw material charge amount corresponds to a batch. The particle size is represented by 3 types of large particles, medium particles and small particles according to the particle size distribution in the actual raw material, and the particle size ratio of the large particles, medium particles and small particles is set to 3.8 according to the actual raw material: 2.0:1.0. the large particles, the medium particles and the small particles each have the same mass. At this time, the same bin was used for coke under conditions 1 and 2, and the charging conditions were the same.
Fig. 12 shows the average result of the reverse tilting loading.
As shown in fig. 12, in condition 1 (invention example), a raw material particle size distribution suitable for the counter-tilting loading in the top bin can be achieved. That is, when the large particles are charged in a reverse tilting manner, the large particles are accumulated near the raw material discharge port, and a large number of the large particles can be discharged at the initial stage of discharge from the top bin. In addition, the particle size distribution of the raw material in the furnace top bin suitable for positive tilting loading can be realized. That is, when the material is loaded in a positive tilting motion, large particles are collected at a position distant from the material discharge port, and a large number of large particles can be discharged at the end of discharge from the top bin.
On the other hand, in condition 2 (comparative example), large particles cannot be sufficiently collected near the raw material discharge port during the anti-tilting loading, and the raw material particle size distribution in the top bin suitable for the anti-tilting loading cannot be achieved.
Based on the condition of the condition 1 (invention example), substantially the same results as the condition 1 (invention example) were obtained even when the shape of the structure was variously changed in the range of α=25 to 45 °, β=25 to 45 °, γ=25 to 45 °. In addition, even when the position of the top of the structure was variously changed in the range of R/r=0 to 0.6, substantially the same results as in the condition 1 (inventive example) were obtained. Further, as the shape of the structure, the same results as those of the condition 1 (invention example) can be obtained even in the other shapes such as the oblique conical shape and the elliptic conical shape described above.
In addition, in order to confirm the accuracy of the particle size distribution in the furnace roof bin by the above numerical simulation, a model experiment was performed.
Specifically, as shown in fig. 13, a furnace top bin model of a size of 1/17.8 of the actual machine corresponding to the condition 1 (invention example) and the condition 2 (comparative example) was prepared. In the figure, reference numeral 10 denotes a loading conveyor, 11 denotes a furnace top bin model, 12 denotes a collection hopper model, 13 denotes a sampling box, 14 denotes a roller conveyor, 15 denotes a sampling box conveyor, and 16 denotes a segregation control panel model or a structural body model.
The raw material, here ore, is then charged from a charging conveyor into a furnace top silo model. The loading position of the raw material (the collision position of the raw material in the segregation control plate model and the structure model) is adjusted by changing the position of the loading conveyor. After the furnace top bin model is installed, a valve of a discharge port connected with the lower end of the furnace top bin model is opened, and raw materials are discharged from the discharge port. Then, the discharged raw material is collected with a plurality of sampling boxes. At this time, the sampling box is gradually moved in the horizontal direction by the sampling box conveyor, and the discharged raw materials are sorted in time series at regular intervals from the start of discharge to the end of discharge. Then, the raw materials collected in each sampling tank are screened, the average particle diameter of the raw materials collected in each sampling tank is calculated, and then the average particle diameter of the raw materials before all the raw materials are loaded into a furnace top bin model is divided, so that the non-dimensionalized particle diameter of the raw materials in each non-dimensionalized discharge time is calculated. The results are shown in fig. 14 and 15.
From fig. 14 and 15, data supporting the above-described numerical simulation results were also obtained in this model test.
That is, in the condition 1 (invention example), when the charging is positively tilted, a large number of large particles are discharged at the end of the discharge of the top bin. In addition, when the reverse tilting is carried out, a lot of large particles are discharged at the initial stage of discharging the top bin.
On the other hand, in condition 2 (comparative example), when the reverse tilting is carried out, a large number of large particles cannot be discharged at the initial stage of discharging the top bin as compared with condition 1 (inventive example).
Description of the reference numerals
1: blast furnace
2: tuyere (wind gap)
3: ore layer
4: coke layer
5: molten layer
6: furnace top stock bin
6-1: raw material storage unit
6-2: raw material discharge port
6-3: segregation control panel
6-4: structure body
6-5: raw material collision surface
6-6: dispersion regulating plate
7: flow regulating door
8: collecting hopper
9: rotary chute
10: loading conveyor
11: furnace top stock bin model
12: collecting hopper model
13: sampling box
14: roller conveyer belt
15: conveyor belt for sampling box
16: segregation control panel model or structure model
17: movable control panel
Claims (4)
1. A method for charging raw materials into a blast furnace,
the blast furnace is provided with a furnace top bin at the top part of the furnace,
At least one of the furnace roof bins is provided with:
a raw material storage part,
a raw material loading port for loading the raw material into the raw material storage portion from above the raw material storage portion,
a structure body provided in the raw material storage portion and having a raw material collision surface against which the raw material charged from the raw material charging port collides, and
a raw material discharge port for discharging the raw material in the raw material storage unit to a lower side of the raw material storage unit;
the raw material discharge port is eccentrically disposed from the center of the raw material storage portion in a horizontal plane,
the material collision surface of the structure is inclined downward from the top of the structure toward the end of the material collision surface in at least the eccentric direction, the opposite eccentric direction, and the 1 st and 2 nd directions perpendicular to the eccentric direction and the vertical direction,
the method for charging raw materials into a blast furnace comprises the following steps:
a storage step of loading a raw material into the raw material storage unit from the raw material loading port of the top bin, causing the raw material to collide with the structure, then storing the raw material in the raw material storage unit, a loading step of discharging the raw material stored in the raw material storage unit from the raw material discharge port, loading the discharged raw material into the blast furnace through a rotating chute of the blast furnace,
Determining a raw material collision position in the structure of the storage step based on a tilting manner of the loading step,
here, the eccentric direction is a direction in which the raw material discharge port is eccentric from the center of the raw material storage portion on the horizontal plane, and the opposite eccentric direction is a direction opposite to the eccentric direction on the same horizontal plane.
2. The raw material charging method for a blast furnace according to claim 1, wherein inclination angles α and α' of a line segment connecting a top of the structural body and an end of the raw material collision surface in the eccentric direction and the opposite eccentric direction with respect to a horizontal direction are 25 to 45 °, respectively.
3. The blast furnace raw material charging method according to claim 1 or 2, wherein inclination angles β and γ of line segments connecting the top of the structure and the end of the raw material collision surface in the 1 st direction and the 2 nd direction with respect to a horizontal direction are 25 to 45 °, respectively.
4. The method for charging a blast furnace raw material according to any one of claims 1 to 3, wherein the top of the structure is located in a range of 0 to 0.6 in a dimensionless distance R/R from the center of the raw material reservoir section on a horizontal plane,
here, the dimensionless distance R/R refers to a value obtained by dividing the distance R from the center of the raw material reservoir section on the horizontal plane by the inner diameter R of the raw material reservoir section.
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| Application Number | Priority Date | Filing Date | Title |
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| JP2021-025657 | 2021-02-19 | ||
| JP2021025657 | 2021-02-19 | ||
| PCT/JP2022/002471 WO2022176518A1 (en) | 2021-02-19 | 2022-01-24 | Method for charging raw material into blast furnace |
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| CN116710577A true CN116710577A (en) | 2023-09-05 |
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| CN202280009877.XA Pending CN116710577A (en) | 2021-02-19 | 2022-01-24 | Method for charging raw materials into blast furnace |
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|---|---|
| EP (1) | EP4276202A4 (en) |
| JP (1) | JP7343052B2 (en) |
| KR (1) | KR20230109743A (en) |
| CN (1) | CN116710577A (en) |
| WO (1) | WO2022176518A1 (en) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS62218507A (en) * | 1986-03-17 | 1987-09-25 | Sumitomo Metal Ind Ltd | Raw material charging method for bell-less blast furnace |
| JP4460661B2 (en) | 1998-12-15 | 2010-05-12 | Ｊｆｅスチール株式会社 | How to use blast furnace top bunker |
| JP4591520B2 (en) | 2008-02-15 | 2010-12-01 | Ｊｆｅスチール株式会社 | Raw material charging method for blast furnace using furnace top bunker and bellless type charging equipment |
| JP5810509B2 (en) * | 2009-11-24 | 2015-11-11 | Ｊｆｅスチール株式会社 | Material segregation equipment for blast furnace top bunker |
| JP2012072471A (en) * | 2010-09-29 | 2012-04-12 | Jfe Steel Corp | Furnace top bunker, and charging method of raw material to blast furnace using the same |
| JP2016053201A (en) * | 2014-09-04 | 2016-04-14 | Ｊｆｅスチール株式会社 | Method for charging raw material into blast furnace |
| JP6304174B2 (en) * | 2015-08-19 | 2018-04-04 | Ｊｆｅスチール株式会社 | Raw material charging method to blast furnace |
-
2022
- 2022-01-24 CN CN202280009877.XA patent/CN116710577A/en active Pending
- 2022-01-24 KR KR1020237021180A patent/KR20230109743A/en unknown
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- 2022-01-24 WO PCT/JP2022/002471 patent/WO2022176518A1/en active Application Filing
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| JP7343052B2 (en) | 2023-09-12 |
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| WO2022176518A1 (en) | 2022-08-25 |
| EP4276202A1 (en) | 2023-11-15 |
| JPWO2022176518A1 (en) | 2022-08-25 |
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