KR20170134701A - Apparatus for loading material into blast furnace - Google Patents

Abstract

It is an object of the present invention to improve the segregation precision that intentionally segregates the grain size of the blast furnace raw material in the hearth bunker. A slope plate 11 disposed in the hearth bunker 10 for guiding the blast furnace material introduced into the hearth bunker 10 toward the wall surface and a slope plate 11 for guiding the portion P of the acid of the blast furnace material stored in the hearth bunker 10, And a tilt angle adjusting unit for changing the tilt angle of the swash plate in a direction to be continuously or intermittently decreased in accordance with a change in the height determined by the normal determining unit, (14). The first blast furnace raw material, which is in the range of 1/10 or less of the initial charge, is an ore raw material containing no coke.

Description

[0001] APPARATUS FOR LOADING MATERIAL INTO BLAST FURNACE [0002]

The present invention relates to a technique for segregating and storing a blast furnace raw material in a bunker top furnace for charging a blast furnace raw material into a blast furnace disposed above the blast furnace.

Recently, CO ₂ reduction has been demanded from the viewpoint of preventing global warming.

In the steel industry, about 70% of the CO ₂ emission amount is caused by the blast furnace, and it is required to reduce the CO ₂ emission amount in the blast furnace. CO ₂ reduction in the blast furnace is possible by reducing the reducing materials (coke, pulverized coal, natural gas, etc.) used in the blast furnace.

However, when the reducing material used in the blast furnace, in particular, the coke is reduced, the coke securing the air permeability in the furnace is reduced, so that the aeration resistance in the blast furnace increases. That is, in a general blast furnace, when the ore charged from the furnace reaches the temperature at which the softening starts, the blast furnace is deformed by filling the gap with the load of the blast furnace material present at the top. Therefore, in the lower part of the blast furnace, a fusion bond is formed in which the air resistance of the ore layer is very large and gas hardly flows. The air permeability of the fused block largely affects the air permeability of the entire blast furnace, and the productivity in the blast furnace is controlled.

In order to improve the ventilation resistance of the fusing belt, it is known that it is effective to use a mixed raw material in which coke is mixed in the ore layer. Many inventions have been reported for mixing coke in the ore layer.

For example, in Patent Document 1, a coke is charged in a hopper on the downstream side of an ore hopper, a coke is deposited on an ore on a conveyor, and the coke is charged into a runoff bunker, To be charged into the blast furnace. Patent Document 2 discloses three methods of storing coke and ore separately in a reclamation bunker and mixing the coke and ore at the same time so that the coke can be placed in a general charging manner, At the same time. In Patent Document 3, in order to prevent unstable fusing belt shape in the blast furnace operation and the lowering of the gas utilization rate in the vicinity of the central portion, and to stabilize the operation and improve the thermal efficiency, the blast furnace raw material charging In the method, the entire ore and the entire coke are thoroughly mixed and then charged into the furnace.

Further, in order to enjoy the effect of reducing the ventilation resistance in the fused portion by the mixed raw material, it is necessary to appropriately control the loading position of the mixed raw material in the blast furnace. For this reason, segregation techniques for blast furnace raw materials, which are conventionally charged into a blast furnace bunker, have been developed. This is a technique for controlling the timing of discharge of the mixed raw material from the blast furnace bunker by segregating the coke in the blast furnace bunker in order to arbitrarily mix the coke at the point where the amount of ore is large and the air permeability is poor.

As such a segregating technique, Patent Document 4 proposes that a tilting plate capable of tilting freely to change the falling direction of the blast furnace raw material is formed, and the loading position of the blast furnace raw material is set so that the grain size of the blast furnace raw material is intentionally segregated have. Patent Document 4 discloses that, by segregating the particle size of the blast furnace material in the run-down bunker, the coke can be charged into the furnace at a preferable timing for discharging the blended raw material.

Patent Document 5 discloses that an segregation induction cylinder which does not interfere with the inner wall of the run-down bunker is employed to form a blast furnace dropping hole near the inner wall surface near the center of the furnace body to improve the segregation effect of the blast furnace raw material .

Patent Document 6 discloses a segregation device for segregating and charging a blast furnace raw material into a hearth bunker formed in a hearth of a blast furnace, wherein the furnace bunker is rotatable around a vertical axis of a central portion of a transverse section of the hearth bunker, And a segregation distributor larger than the angle of repose of the blast furnace raw material is provided in the upper part of the hearth bunker.

In the apparatus described in Patent Document 7, a segregation control plate capable of tilting freely changing the falling direction due to the contact of the blast furnace material with the interior of the hearth bunker is disposed, and the segregation control plate on the opposite side And a magnet for reducing the amount of the blast furnace raw material charged per unit area as the raw material deposition surface is disposed on the side of the blast furnace. According to this configuration, when the blast furnace raw material supplied to the run-down bunker comes into contact with the segregation control plate, the abutting width of the blast furnace raw material to the segregation control plate is expanded by the attracting force of the magnet. As a result, the amount of the blast furnace raw material deposited per unit area relative to the blast furnace deposition surface is reduced to prevent collapse or collapse on the deposition surface, and the segregation phenomenon of fine and coarse grains in the hearth bunker is strengthened, To control the powder particle size distribution of the blast furnace to a desired pattern.

Japanese Patent Application Laid-Open No. 3-211210 Japanese Patent Application Laid-Open No. 16-107794 Japanese Laid-Open Patent Publication No. 53-152800 Japanese Patent Application Laid-Open No. 2008-179899 Japanese Laid-Open Patent Publication No. 2011-132597 Japanese Laid-Open Patent Publication No. 2012-132056 Japanese Laid-Open Patent Publication No. 2012-72471

However, none of the patent documents consider the change in the deposition shape of the blast furnace material stored in the hearth bunker. Therefore, the precision of the segregation of the blast furnace material stored in the hearth bunker is not so good.

The present invention has been made in view of the above-described points, and aims to improve the segregation precision in which the grain size of the blast furnace raw material is intentionally segregated.

As a result of the investigation by the inventors of the present invention, it has been found that when the position of the top of the mountain of the material deposited in the runner bunker is apart from the runner bunker wall when viewed from the top surface, And the segregation of the mixed coke is promoted as the skirt portion is longer, so that particle size segregation is promoted. That is, it is difficult to inject the raw material with a good precision so as to be deviated to one side of the acid in the blast furnace deposition surface.

Even if the position of the top of the acid in the blast furnace material accumulated in the runner bunker is close to the wall of the runner bunker when viewed from the top surface and the material comes into contact with the side of the runner bunker wall close to the top of the runner bunker, It is found that the recoil from the wall surface of the hearth bunker becomes large, which also causes a deterioration in the accuracy of segregation.

That is, in order to solve the problem, the raw material charging apparatus for a blast furnace according to an embodiment of the present invention comprises a raw material charging device for blast furnace for segregating and storing the blast furnace raw material charged into the furnace bunker for charging into the blast furnace, A slope plate disposed in the hearth bunker for receiving the blast furnace material introduced into the hearth bunker and guiding the blast furnace material toward a wall surface in the hearth bunker, and a control unit for detecting the height of the peak of the furnace material in the furnace bunker, A normal judgment section for judging whether or not the level of the blast furnace bunker is higher than an initial injection amount set in advance in the normal bunker, From the wall surface position toward the wall surface position located in the range of the position above the predetermined margin And an inclination angle adjusting section for changing the inclination angle of the swash plate in accordance with the height judged by the normal judging section so that the raw material is guided to the first inclined angle, The raw material is characterized by being an ore raw material containing no coke.

In the state where the inclined plate is inclined at a depression angle in the same direction and the introduced blast furnace raw material is guided in the swash plate, the blast furnace slope is located at the side of the wall side of the blast furnace, It is stored in the bunker.

At this time, in the present invention, by introducing the blast furnace raw material charged toward the wall surface position in the range of the margin from the same height as that of the retained acid, control of the position of the accumulated acid to the position of the wall surface or the wall surface It is possible to suppress the adverse effect caused by the repulsion from the wall surface and the protrusion.

Therefore, the acid of the deposited blast furnace raw material is deposited in a state of inclined slopes only in one direction from the wall surface, so that grain size segregation can be generated with better precision.

Therefore, according to the present invention, it becomes possible to discharge the mixed raw materials from the furnace furnace in the order of granulation and granulation, so that it becomes possible to charge a large amount of coke at an arbitrary position in the blast furnace. This makes it possible to improve the reactivity in the furnace, leading to reduction of the reducing cost.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic diagram for explaining a lumber bunker and a raw material charging apparatus according to an embodiment based on the present invention. Fig.
2 is a view showing an example of a raw material deposition situation in a blast furnace.
3 is a view for explaining the problem of the deposition state of the conventional blast furnace raw material.
4 is a graph showing the change in the amount of the mixed material in the blast furnace raw material discharged from the hearth bunker on the upper part of the blast furnace.
5 is a graph showing standard deviations of mixing degrees in the inventive example and comparative example.
6 is a view for explaining a change in warpage of the swash plate.

Next, an embodiment of the present invention will be described with reference to the drawings.

Here, the drawings are schematic, and the dimensions and the like are different from the reality. It should be noted that the embodiments described below exemplify the structure for embodying the technical idea of the present invention, and the technical idea of the present invention is not limited to the following structure and the like. The technical spirit of the present invention may be modified in various ways within the technical scope defined by the claims in the claims.

(Configuration)

As shown in Fig. 1, the apparatus for charging raw materials into the blast furnace is provided with a furnace bunker 10, a tiltable tilting plate 11 disposed in the furnace bunker 10, a driving unit (not shown) for changing the tilting angle? 12, a steady-state determining section 13, and a tilt angle adjusting section 14.

The hearth bunker 10 is disposed in the hearth of the blast furnace 20.

As shown in Fig. 1, the hearth bunker 10 of this embodiment is provided with a charging port 10a at its upper end and a discharging port 10b at its lower end. In Fig. 1, the discharge port 10b is biased to the left.

The blast furnace raw material transferred by the belt conveyor 15 to the inlet 10a of the furnace bunker 10 is sequentially introduced into the furnace bunker 10 from the inlet 10a.

Here, as shown in Fig. 1, the blast furnace material on the belt conveyor 15 is conveyed in the state that the ore raw material 16 is deposited on the lower layer and the coke 17 is deposited thereon. It should be noted that the coke 17 is not deposited on the ore raw material 16 in the initial portion of the feed into the hearth bunker 10 and only a predetermined amount of the ore raw material 16 is fed into the hearth bunker 10 (&Quot; 1 " portion in Fig. 1). As a result, the first blast furnace raw material to be fed into the hearth bunker 10 can be made only from the ore raw material. Thereafter, the mixed raw material composed of the mixed material of the ore raw material 16 and the coke 17 is set to be injected into the hearth bunker 10 (the portion of "2" and "3" in FIG. 1). The ore raw material 16 is an ore raw material such as sintered ores, ore or pellets.

The swash plate 11 is disposed below the position where the blast furnace material charged from the inlet 10a falls down and the blast furnace material charged from the inlet 10a abuts the upper surface of the swash plate 11. [

The inclined plate 11 is inclined at a predetermined incline angle with respect to the horizontal direction and the inclined direction is set such that the side of the wall surface 10c of the runner bunker 10 located on the side remote from the discharge port 10b It is inclined to be below. In Fig. 1, the swash plate 11 is inclined toward the right wall surface 10c side. The inclination angle [theta] of the swash plate 11 is defined as a rising angle with respect to the horizontal direction.

Further, rising portions (not shown) rising upwards on both sides in the width direction of the swash plate 11 may be formed so that the blast furnace material is hardly overflowed from both sides in the width direction.

The swash plate 11 has a shaft portion oriented to the left and right axes and is supported on the runner bunker 10 via the shaft portion. The swash plate 11 is capable of tilting with its shaft portion as a rotation axis.

And a driving unit 12 for axially rotating the shaft is connected to the shaft. The driving unit 12 is, for example, a stepping motor. This driving unit 12 is located outside the hearth bunker 10.

The normal judgment section 13 is a device for judging the height of the mountain portion P of the blast furnace raw material 1 accumulated in the runner bunker 10 by detection or estimation.

1, the blast furnace raw material 1 is guided toward the right side. Therefore, the blast furnace raw material 1 stored in the hearth bunker 10 is deposited on the right side of Fig. 1 with the blast furnace P of the raw material 1 shifted Goes. Therefore, by detecting the deposition state of the blast furnace raw material on the right side, the height of the peak P of the blast furnace raw material 1 can be detected.

The steady determining portion 13 of the present embodiment is constituted by a distance meter such as a laser distance meter. The normal determining section 13 is disposed above the side of the wall surface 10c from which the material is guided in the swash plate 11 and measures the distance to the position of the blast furnace 1 located below, P is detected. A plurality of laser rangefinders may be arranged so as to be aligned in the oblique direction of the swash plate 11 and the peak P of the acid may be detected from the detection values of the plurality of laser rangefinders. For example, the distance is measured along the slope of the deposition surface to be formed, and the position where the extension line of the detected plurality of points intersects with the wall surface of the hearth bunker 10 is regarded as the height of the peak P of the peak. Although FIG. 1 exemplifies the case where there are two distance meters, there may be three or more.

The configuration of the normal judgment section 13 is not limited to this. For example, the relationship between the input amount or weight of the blast furnace raw material to the run-of-the-mill bunker 10 and the height of the peak P of the accumulated blast furnace raw material 1 is obtained from experiments and theories, The height of the portion P may be determined by estimating the amount P of the acid to be deposited on the basis of the amount of the supplied amount of the unburned bunker 10 and the peak P of the acid deposited from the above relationship.

The inclination angle adjusting section 14 adjusts the position of the wall surface of the reclamation bunker 10 at the height equal to the height determined by the normal judgment section 13 or the position The inclination angle? Of the swash plate 11 is changed so as to continuously or intermittently decrease in accordance with the change in the height determined by the normal determination section 13 so that the blast furnace material is induced at the wall position in the range of .

The margin is at most 1 m. This is because it is confirmed that if the height is within 1 m from the height of the portion P, there is little problem caused by collision with the wall surface and repulsion. The margin is preferably 0.5 m.

Here, from the experiment or the theory, the trajectory of the free fall from the inclined plate 11 is obtained in association with the inclination angle?, While the blast furnace material falling and coming into contact with the inclined plate 11 is guided along the inclined plate 11. [ The relationship between the inclination angle? And the average position at which the blast furnace material derived from the swash plate 11 abuts against the wall surface is obtained and stored in a storage unit in the form of a table, relational expression or the like.

The inclination angle adjusting section 14 obtains an inclination angle? Capable of guiding the blast furnace material at the position of the wall surface of the reclamation bunker 10 at the height equal to the height determined by the normal judgment section 13 on the basis of the information of the storage section , And changes the inclination angle [theta] of the swash plate 11 to be the obtained inclination angle [theta]. The position of the wall surface of the hearth bunker 10 at the height equal to the height judged by the normal judging section 13 is 10 cm to 20 cm higher than the wall surface position of the hearth bunker 10 because there is a variation in the induction of the blast furnace material from the swash plate 11. [ To obtain the inclination angle &thetas; and to derive the blast furnace raw material. The adjustment of the inclination angle may be performed continuously at a predetermined sampling time or may be changed every time the height change of the portion P changes by a predetermined amount or more.

The inclination angle adjusting section 14 starts when it is judged that the blast furnace material having the amount equal to or higher than the initial charging amount set in advance in the runoff bunker 10 is charged and stored. For example, when the normal judgment section 13 detects an increase in the material layer, it is judged that the blast furnace material in the furnace bunker 10 is stored in the blast furnace higher than the initial charging amount. Even if it is determined by the other means that the raw material of the blast furnace exceeding the initial charged amount has been stored, for example, by determining the weight of the hearth bunker 10 and detecting the increase in weight corresponding to the initial charged amount, do.

Here, the blast furnace raw material charged in the range of the first 1/10 or more of the initial amount of the input amount of the raw material layer is used as the ore raw material containing no coke. Since the blast furnace material in the area initially put into the hearth bunker 10 is discharged from the hearth bunker at the earliest stage, it is charged in the center of the blast non-dimensional radius. On the other hand, it is necessary to improve the reactivity of the ore layer by the mixed coke, which is the middle part of the ore layer with a large amount of ore. From such a viewpoint, it is preferable that the mixed coke is most mixed in the middle of the discharge. This is because it is necessary to reduce coke to be mixed at the initial stage of discharge. Therefore, it is preferable that no mixed coke is contained in the initial stage of raw material discharge. In this way, only the ore raw material is deposited in the initial portion including the discharge port 10b of the run-of-the-mill bunker 10. In this case, too, the coarse ore having a large particle diameter is segregated and stored mainly on the side of the discharge port 10b since it is once stored after coming into contact with the swash plate 11. [ Half of the initial charge, or even all, may be raw ores that do not contain coke.

The initial angle of the inclination angle? Of the swash plate 11 with respect to the horizontal direction is 45 degrees. In this embodiment, when it is determined that the inclination angle? Is less than 25 degrees, loading of the blast furnace raw material into the runoff bunker 10 is terminated. Other conditions may be adopted for the charging termination condition of the blast furnace raw material.

However, when the inclination angle? Is excessively large, there is a fear that the material can not be guided to the wall surface. On the contrary, if the inclination angle? Is excessively small, the raw material tends to drop more than a predetermined amount from the side of the inclination angle?, And the falling speed can not be obtained and the material can not be guided to the wall surface. From this viewpoint, in this embodiment, the inclination angle? Is set in the range of 45 degrees to 25 degrees. Further, since the inclination angle? Is made smaller as the acid is increased, in the present embodiment, the case where the inclination angle is less than 25 degrees is set as the charging completion.

(Action and others)

In recent years, in the blast furnace operation, the flow rate distribution in the furnace radial direction of the gas rising in the blast furnace 20 is adjusted by appropriately distributing the particle size distribution in the furnace, and the air permeability in the furnace, The heat load of the heat exchanger is desired. Specifically, it is believed that the operation of flowing a large amount of gas at the center of the furnace is desirable. In addition, this is called central flow or central flow operation.

Such a flow rate distribution of gas (hereinafter simply referred to as a gas flow distribution) is mainly determined by the ratio of the thickness of the ore layer and the coke layer formed in the furnace or the particle size distribution in the furnace radial direction . Particularly, in the case of using a belly type charging device in which the turning chute 21 is provided and the hearth bunkers 10 are arranged in parallel in the furnace, when the furnace bunker 10 is charged with the blast furnace raw material, It is classified on the slope, and the grain is caused by the grain. In other words, the granular material is segregated toward the right side wall, which is the fall position, so that the granules are discharged from the outlet 10b, The side is segregated to the left side and deposited.

As a result, the blast furnace raw material can be discharged from the discharge port 10b of the hearth bunker 10 in the order of assembly, neutralization, fine granulation, and the like. By stacking the granules in the blast furnace 20 in such a manner that the granules are discharged on a granular basis, the granulation can be deposited at the center of the blast furnace 20, and the gas flow distribution in which the central flow is developed can be stably obtained.

When the blast furnace raw material is discharged from the hearth bunker 10 to the orbiting chute 21 in the blast furnace 20 disposed below the furnace bunker 10 when the blast furnace 20 is loaded into the blast furnace 20, There is no phenomenon such as collapse of raw materials in the sedimentation blast furnace rather than depositing the blast furnace raw material from the upper side of slope on the pestle bowl side from the furnace wall side to deposit the blast furnace raw material from the lower side of slope on the pestle bowl , And a desired deposition shape is obtained. In consideration of this, in the present embodiment, the leading end of the swing chute 21 is set so as to be tilted while being tilted in the peripheral direction from the central portion of the furnace, so that the blast furnace material is charged (reversely charged).

That is to say, by carrying out reverse gyro loading in which the leading end of the swivel chute 21 is turned while tilting gradually from the center of the blast furnace 20 to the periphery, the drop position of the blast furnace material in the run- So that a predetermined blast furnace particle size distribution is obtained. Then, by sending out the same to the swing chute 21 as described above, assembling is performed at the center of the blast furnace 20, and fine grains are gathered at the peripheral portion.

In the above description, it is assumed that the distribution of the gas flow in which the central flow is developed is obtained. However, when it is desired to develop the peripheral flow by the intention of the operator, the gas flow is gradually turned from the periphery of the blast furnace 20 toward the center The assembly may be arranged on the peripheral side by tilting.

A plurality of launder bunkers are disposed on the upper part of the blast furnace 20, and the blast furnace materials of the launder bunkers 10 are loaded in the blast furnace 20 in a predetermined order. The present invention is particularly effective when a mixed material is charged.

The fact that the steady-state determination section 13 detects the increase of the raw material layer, that is, the control of the inclined plate 11 is started after the blast furnace raw material having been stored in the furnace bunker 10 in an amount equal to or higher than the initial amount set in advance is stored, This is because it is difficult to guide the material toward the portion P of the accumulated blast furnace raw material.

Example

Fig. 2 shows a deposition shape of a common blast furnace raw material in the blast furnace 20. Fig. The stock line shown in Fig. 2 is a position to be a reference for charging the blast furnace raw material and serves as a reference for loading the raw material. As can be seen from Fig. 2, it can be seen that the ore 1 is concentrated and deposited in the vicinity of 0.3 to 0.7 in the dimensionless radius. Since ore is as small as one-third of the coke and the gas is difficult to shed, it is necessary to improve the reactivity of the ore in this portion and it is considered effective to mix the coke in this portion. Since the ore 1 is charged toward a non-dimensional radius of 0 to 1, it is considered effective to discharge the raw material mixture from the initial stage of discharge to the middle stage in order to mix the coke in this portion.

Fig. 3 shows the lumber bunker 10 of the comparative example disposed above the blast furnace 20. Fig. In the furnace bunker 10, the blast furnace material of the portion " 1 " near the discharge port 10b is discharged first. In Comparative Example 2, the portion of "1" is also mixed coke. Subsequently, the blast furnace material of the portion " 2 " located immediately above the discharge port 10b is discharged, and then the portion " 3 " In addition, in the hearth bunker 10, the assembly is segregated in the lower part of the deposition surface depending on the particle size of the blast furnace raw material. Here, the coke to be charged into the hearth bunker 10 is larger than the ore, so that it is segregated in the lower part of the skirt portion. That is, if the coke can be segregated at the portion " 2 " in Fig. 3, it becomes possible to concentrate the mixed raw material in a non-dimensional radius of about 0.3 to 0.7.

However, in the case where the angle of the swash plate 11 is not adjusted in accordance with the portion P of the blast furnace deposition surface (the upper surface of the accumulated blast furnace raw material 1) during the charging of the blast furnace raw material one time, A skirt portion is also generated in the portion of the raw material " 3 ", and there is a blast furnace material segregated in the portion " 3 ".

On the other hand, in the present embodiment, in order to avoid this, the angle of the swash plate 11 is controlled in accordance with the portion P of the blast furnace deposition surface, and as shown in Fig. 1, (P) of the raw material deposit (1) is formed on the wall surface of the discharge port (remote side) so as to form a skirt portion toward the discharge port (10b).

According to this embodiment, as shown in Fig. 3, the coke charged at the end of the discharge is segregated in the portion of the raw material "3" in the sedimentation furnace in the past, and the control of the charging position of the mixed raw material becomes more accurate.

Here, it is found that the height of the blast furnace raw material loading position from the blast furnace raw material entrance face and the blending timing when mixing the blended raw material with the ore greatly affect the coke blending amount. Therefore, the blast furnace 20) were evaluated.

Examples 1 to 4 and Comparative Example 2 are examples in which the angle of the swash plate 11 is adjusted in accordance with the portion P of the blast furnace deposition surface (the upper surface of the accumulated blast furnace raw material 1) Example 1 is a case where the inclination angle of the swash plate 11 is fixed at 25 degrees.

In Inventive Examples 1 to 4 and Comparative Example 1, the mixed-mixing timing was delayed. Examples 1, 2 and 4 and Comparative Example 1 show that when 1/10 of the initial charge amount is an ore raw material containing no coke In Inventive Example 3, 2/10 of the initial charge amount is an ore raw material containing no coke. Comparative Example 2 is an example in which there is no part of the ore raw material containing no coke.

Fig. 4 shows the relationship between the emission ratio and the mixing ratio in each of the inventive examples and comparative examples. The standard deviation of each mixing degree in each of the inventive examples and comparative examples is shown. As can be seen from these, in the inventive example, segregation is significantly suppressed as compared with the comparative example. Specifically, it can be seen that Inventive Example 3 has the smallest segregation and Comparative Example 4 has the largest segregation. When the segregation is suppressed, the coke charged at the end of discharge is reduced, and the control of the charging position of the mixed coke can be more accurately performed.

Table 1 shows the operation results at that time.

As can be seen from Table 1, comparing Examples 1 to 4 and Comparative Example 1 shows that compared with the case where the inclination angle of the swash plate 11 is fixed (Comparative Example 1), as compared with the case where the inclination angle of the swash plate 11 is fixed 11, which are used in Examples 1 to 4 in which the inclination angle is changed, the gas utilization ratio is improved and the reduction ratio is reduced.

As can be seen from Examples 1 to 3 and Inventive Example 4, by restricting the charging height from the raw material surface to 1.0 m or less as in Inventive Examples 1 to 3, the charging height from the raw material surface is larger than 1.0 m It was found that the gas utilization ratio was improved and the reduction ratio was decreased. As described in Example 4, raising the loading height from the blast furnace entrance to the blast furnace is more than 1.0 m, a part of the blast furnace material is repelled to protrude from the wall, and the portion P of the blast furnace deposition in the furnace bunker 10 is smoothed The segregation of the mixed raw materials is suppressed. As a result, a part of the coke is discharged at the end of the discharge of the blast furnace raw material, so that the coke mixing amount becomes uneven, so that the gas utilization ratio is reduced and the reduction cost ratio is increased.

From these results, it is considered desirable to change the inclination angle of the swash plate 11 with the raising of the blast furnace deposition surface, and to set the blast furnace material charging position to 1 m or less.

As can be seen from the comparison between the inventive examples 1 to 4 and the comparative example 2, even when the inclination angle of the inclined plate 11 is changed in accordance with the rise of the blast furnace deposition surface, when the mixing timing of the mixed raw material is "0.0" The mixing timing of the mixed raw materials was made to be 0.1 or more so that the cokes segregated at the beginning could be suppressed and the mixed raw materials could be mixed well in the non-dimensional radius of 0.3 to 0.7, It was confirmed that the utilization ratio was improved and the reduction ratio was reduced.

As described above, the inclination angle of the swash plate 11 is changed in accordance with the increase in the blast furnace deposition surface, and the mixing timing of the blended raw materials is made to be 0.1 or more, thereby improving the gas utilization rate and reducing the reduction cost Could know.

Here, FIG. 6 shows the change in the angle of the swash plate 11 when the discharge rate of the raw material and the charging height from the blast furnace surface are 1 m. Further, while the blast furnace material was continuously charged into the portion where the wall surface was inclined at the lower portion of the hearth bunker 10, the swash plate 11 was kept at 45 degrees.

As a result, the angle of the control panel was kept constant at 45 degrees for the emission rate of 20%, and then monotonously decreased to 25 degrees as the emission rate became 100%. From these, it is preferable that the angle control of the swash plate 11 is monotonously decreased from 45 degrees to 25 degrees in the region where the blast furnace charge ratio is 20% or later.

The entire contents of Japanese Patent Application No. 2015-108624 (filed on May 28, 2015), the contents of which are hereby claimed, are hereby incorporated by reference.

While the present invention has been described with reference to a limited number of embodiments, the scope of rights is not limited thereto, and modifications of the embodiments based on the above disclosure will be apparent to those skilled in the art.

1: The blast furnace raw material
10: Open-end bunker
10a:
10b: outlet
10c: wall surface
11:
12:
13:
14:
15: belt conveyor
16: Ore raw material
17: Coke
20: blast furnace
21: turning suit
P: Government
[theta]: inclination angle

Claims (4)

As a raw material charging device for a blast furnace for segregating and storing a blast furnace raw material charged into a furnace bunker for charging the blast furnace into the furnace bunker,
An inclined plate disposed in the reclamation bunker and guiding the blast furnace raw material introduced into the reclamation bunker toward a wall surface in the reclamation bunker,
A normal judgment section for judging the height of the top of the acid of the blast furnace stock stored in the reclamation bunker by detection or estimation;
Wherein when the blast furnace material is stored in an amount equal to or greater than an initial amount set in advance in the runner bunker, the blast furnace is operated by a predetermined margin from the position of the wall of the runner bunker at the height equal to the height determined by the normal decision section, And an inclination angle adjusting section for changing the inclination angle of the swash plate in accordance with the height determined by the normal determination section so that the blast furnace material is directed toward a wall surface position located in a range of an upper position,
Wherein the first amount of the initial amount of the blast furnace raw material, which is the amount of the initial amount of at least 1/10 of the initial amount of the blast furnace, is an ore raw material containing no coke. The method according to claim 1,
And the margin is 1 m. 3. The method according to claim 1 or 2,
Wherein the blast furnace raw material to be supplied to the runoff bunker is a mixed raw material of the ore raw material and the coke in a state where the tilt angle is adjusted by the tilt angle adjusting unit. 4. The method according to any one of claims 1 to 3,
Wherein when the inclination angle of the swash plate is determined to be 45 degrees at an initial angle of incidence relative to the horizontal direction and the inclination angle is less than 25 degrees, the introduction of the blast furnace material into the reconditioning bunker is terminated Charging device.

Images