KR102062969B1 - Apparatus for loading material into blast furnace - Google Patents

Abstract

It aims at improving the segregation precision which intentionally segregates the particle size of blast furnace raw material in a top bunker. An inclined sloping plate 11 arranged in the top bunker 10 and guiding the blast furnace raw material introduced into the top bunker 10 toward the wall surface, and the peak of the mountain of the blast furnace raw material stored in the top bunker 10 (P). The normal determination part 13 which determines the height of the inclination, and the inclination angle adjustment part which changes the inclination-angle (theta) of the inclination board 11 to the direction which becomes small continuously or intermittently according to the change of the height which the normal determination part 13 judged. 14 is provided. The blast furnace raw material input for the first time which is the quantity of 1/10 or less of initial stage inputs is an ore raw material which does not contain coke.

Description

Raw material charging device to blast furnace {APPARATUS FOR LOADING MATERIAL INTO BLAST FURNACE}

TECHNICAL FIELD This invention relates to the technique which arrange | positions blast furnace raw material and accumulate | stores in the bunker bunker which is arrange | positioned at the upper part of a blast furnace for charging blast furnace raw material in a blast furnace.

In recent years, the CO ₂ reduction is required in terms of global warming.

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

However, when the reducing material used for a blast furnace, especially coke, is reduced, since the coke which ensures air permeability in a furnace reduces, the ventilation resistance in a blast furnace increases. That is, in the general blast furnace, when the ore charged from the top reaches the temperature which starts softening, it deforms, filling the space | gap by the load of the blast furnace raw material which exists in the upper part. Therefore, in the lower part of the blast furnace, a fusion zone in which the airflow resistance of the ore layer is very large and gas hardly flows is formed. The air permeability of this fusion zone greatly affects the air permeability of the entire blast furnace, and the productivity in the blast furnace is kept at a constant rate.

In order to improve the air permeation resistance of a fusion | melting band, it is known that it is effective to use the mixed raw material which mixed coke to the ore layer, and many inventions are reported in order to mix coke to this ore layer.

For example, in Patent Literature 1, in a belly-type blast furnace, coke is charged into a hopper downstream of an ore hopper, and coke is deposited on an ore on a conveyor, then charged into a top bunker, and the ore and coke are turned into a chute. It is charged in the blast furnace through the interposition. In Patent Literature 2, ores and coke are separately stored in a top bunker, and coke and ore are mixed and charged at the same time, thereby providing three methods of a normal charging batch of coke, a central charging batch of coke, and a batch for mixing charging. At the same time. Moreover, in patent document 3, in order to prevent the instability of a fusion | melting zone shape in blast furnace operation, and the fall of the gas utilization rate in the vicinity of central part, and to aim at stable operation and the improvement of thermal efficiency, the blast furnace raw material charging in a blast furnace is carried out. In the method, the whole ore and the whole coke are mixed thoroughly and then charged in a furnace.

Moreover, in order to smell the effect of reducing the airflow resistance in the fusion zone by the mixed raw materials, it is necessary to appropriately control the charging position of the mixed raw materials in the blast furnace. For this reason, the segregation technique of the blast furnace raw material currently charged to blast furnace top bunker is developed. This is a technique for controlling the discharge timing of the mixed raw material from the blast furnace top bunker by segregating the coke in the blast furnace top bunker in order to arbitrarily mix the coke at the point where the amount of ore is charged and the air permeability is poor.

As such a technique for segregation, Patent Document 4 proposes to intentionally segregate the particle size of the blast furnace raw material by forming a tiltable plate that can be freely tilted to change the fall direction of the blast furnace raw material, and setting the charging position of the blast furnace raw material. have. Patent document 4 describes that by segregating the blast furnace raw material particle size in the top bunker as described above, coke can be charged into the furnace at a timing at which discharge of the mixed raw material is desirable.

In addition, Patent Document 5 discloses that a segregation induction cylinder which does not interfere with the inner wall of the top bunker is adopted, the blast furnace raw material dropping port is formed near the inner wall surface near the center of the furnace body, and the segregation effect of the blast furnace raw material is described. It is.

In addition, Patent Literature 6 discloses a segregation apparatus for segregating and charging blast furnace raw materials in a top bunker formed in a blast furnace, which is rotatable about a vertical axis in the center of the cross section of the top bunker, and receives a blast furnace raw material charged from above. A segregation distributor larger than the angle of repose of the blast furnace raw material is provided in the upper part of the top bunker.

Moreover, in the apparatus of patent document 7, the freely tiltable segregation control panel which arranges a blast furnace raw material and changes a fall direction is formed in the inside of a top bunker, and the side of the segregation control panel on the opposite side to the surface which abuts blast furnace raw materials abuts. A magnet is placed on the surface to reduce the amount of charge per unit area of the blast furnace raw material on the blast furnace raw material deposition surface. According to this configuration, when the blast furnace raw material supplied to the top bunker contacts the segregation control panel, the contact width of the blast furnace raw material to the segregation control panel is expanded by the suction force of the magnet. This reduces the amount of charge per unit area of the blast furnace raw material to the blast furnace raw material deposition surface, prevents collapse and collapse on the deposition surface, strengthens segregation of granules and granulation in the top bunker, Patent Literature 7 describes controlling the blast furnace raw material discharge particle size distribution in a desired pattern.

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

However, neither of the patent documents considers a change in the deposition shape of the blast furnace raw material stored in the top bunker. For this reason, the segregation accuracy of the blast furnace raw material stored in the top bunker is not so good.

This invention is made paying attention to the above points, It aims at improving the segregation precision which intentionally segregates the particle size of blast furnace raw material.

As a result of the inventor's examination, when the particle size segregation in the top bunker is carried out by the inclined plate, if the position of the top of the mountain of the material deposited in the top bunker is separated from the top bunker wall when viewed from the top, the wall surface It was found that the skirt portion of the raw material deposited at two points on the side opposite to the side and the wall surface is generated, and the segregation of the mixed coke is promoted as the skirt portion is longer, so that particle size segregation is promoted. In other words, it is difficult to inject the raw materials with good precision so as to be biased to either side of the acid on the blast furnace raw material deposition surface.

In addition, even when the position of the top of the mountain of the blast furnace raw material deposited in the top bunker is close to the top bunker wall when viewed from the top, the material reaches the top bunker wall near to the top of the mountain. When it was higher than predetermined | prescribed height more than predetermined | prescribed height, rebound from the top bunker wall surface became large and discovered that it also causes the precision of segregation to worsen.

That is, in order to solve the subject, the raw material charging apparatus to the blast furnace of one aspect of this invention is a raw material charging apparatus to the blast furnace for segregating and storing the blast furnace raw material thrown into the top bunker for charging into the blast furnace. A slope inclined plate disposed in the top bunker and receiving the blast furnace raw material introduced into the top bunker and directed toward the wall surface of the top bunker, and detecting the height of the mountain of the blast furnace raw material stored in the top bunker or When the blast furnace raw material is stored above the steady-state judging unit determined by the estimation and the initial input amount preset in the top-end bunker, the wall surface position or the wall surface position of the top-side bunker at the same height as that determined by the top-determination unit and From the wall position toward the wall position located in the upper position range by a predetermined margin The blast furnace which is initially introduced is an amount in the range of at least 1/10 of the initial input amount among the initial input amounts, including an inclination angle adjusting unit for changing the inclination angle of the inclined plate according to the height determined by the top determination unit so that the raw material is guided. The raw material is an ore raw material which does not contain coke.

In the state in which the inclined plate is inclined at an inclined angle in the same direction, when the introduced blast furnace raw material is guided from the inclined plate, the blast furnace raw material is exposed in the state in which the government of the blast furnace raw material is deposited on the wall side of the side guided by the inclined plate Is stored in the bunker.

At this time, in the present invention, the blast furnace raw material introduced into the wall position in the range of the margin portion is induced from the same height as that of the stored mountain, thereby controlling the government of the stored acid to the wall position or the position close to the wall surface. In addition, it becomes possible to suppress the adverse effect by repulsion and rebound from a wall surface small.

For this reason, the acid of the blast furnace raw material deposited is deposited in the state which has a slope inclined only in one direction from the said wall surface, and it becomes possible to generate particle size segregation with more precision.

For this reason, according to this invention, since the mixed raw material can be sent out from the blast furnace furnace in the order of granulation and fine granulation, it becomes possible to charge a large amount of coke at arbitrary positions in a blast furnace. This can improve the reactivity in a furnace, and can lead to reduction of a reducing material cost.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram explaining the top bunker and raw material charging apparatus which concern on embodiment based on this invention.
2 is a diagram illustrating an example of raw material deposition situation in a blast furnace.
3 is a view for explaining the problem of the deposition state of a conventional blast furnace raw material.
4 is a view showing a change in the amount of mixed material in the blast furnace raw material discharged from the top bunker of the blast furnace.
5 is a diagram showing standard deviation of respective mixing degrees in the invention example and the comparative example.
It is a figure explaining the time course of an inclination board.

Next, embodiment of this invention is described, referring drawings.

Here, the drawings are schematic, and the dimensions and the like are different from those in reality. Moreover, embodiment shown below illustrates the structure for actualizing the technical idea of this invention, and, as for the technical idea of this invention, a structure etc. are not specified to the following. The technical idea of the present invention can be modified in various ways within the technical scope defined by the claims described in the claims.

(Configuration)

As shown in FIG. 1, the raw material charging apparatus to the blast furnace is a drive part which changes the inclination angle (theta) of the inclined bunker 10, the tiltable inclination plate 11 arrange | positioned in the top bunker 10, and the inclination plate 11 ( 12), the normal determination part 13, and the inclination-angle adjustment part 14 are provided.

The top bunker 10 is disposed at the top of the blast furnace 20.

In the top bunker 10 of this embodiment, as shown in FIG. 1, while the inlet port 10a is formed in the upper end part, the discharge port 10b is provided in the lower end part by shifting to one side. In FIG. 1, the discharge port 10b is formed to the left side.

And the blast furnace raw material conveyed by the belt conveyor 15 to the inlet opening 10a of the top bunker 10 is made to sequentially inject into the top bunker 10 from the inlet 10a.

Here, the blast furnace raw material on the belt conveyor 15 is conveyed in the state which the ore raw material 16 was deposited in the lower layer, and the coke 17 was deposited on it as shown in FIG. However, about the initial stage part into the top bunker 10, the coke 17 is not deposited on the ore raw material 16, and only the ore raw material 16 is initially in the top bunker 10 by a predetermined amount. It inputs ("1" part of FIG. 1). Thereby, the first blast furnace raw material thrown into the top bunker 10 can be used as an ore raw material only. Thereafter, the mixed raw material composed of the mixed material of the ore raw material 16 and the coke 17 is set to be introduced into the top bunker 10 (parts of "2" and "3" in FIG. 1). The ore raw material 16 is an ore raw material such as sintered ore, lump ore and pellets.

The inclined plate 11 is disposed below the position at which the blast furnace raw material introduced from the inlet 10a falls, and the blast furnace raw material introduced from the inlet 10a abuts on the upper surface of the inclined plate 11.

The inclined plate 11 is inclined at a predetermined inclination with respect to the horizontal direction, and the inclined direction of the inclined plate 11 is located at the wall surface 10c side of the top bunker 10 located on the side away from the discharge port 10b. It is inclined down. In FIG. 1, the inclined plate 11 is inclined to the wall surface 10c side on the right side. The inclination angle θ of the inclined plate 11 is defined as an incidence angle with respect to the horizontal direction.

Moreover, the rising part (not shown) may be formed in the width direction both sides of the inclination plate 11, and it may make it hard to flow the blast furnace raw material from both width direction sides.

The inclined plate 11 has a shaft portion facing left and right, and is supported by the top bunker 10 via the shaft portion. And the inclination plate 11 is tiltable by making the shaft part into a rotating shaft.

The drive part 12 which axially rotates the axial part with respect to the axial part is connected. The drive part 12 consists of a stepping motor, for example. This drive part 12 is located outside the top bunker 10.

The top determination unit 13 is a device that determines, by detection or estimation, the height of the peak portion P of the acid of the blast furnace raw material 1 deposited in the top bunker 10.

Here, since the blast furnace raw material is guide | induced toward the right side in FIG. 1, the blast furnace raw material 1 stored in the top bunker 10 is deposited in the right side of FIG. Goes. For this reason, the height of the peak part P of the acid of the blast furnace raw material 1 can be detected by detecting the deposition state of the blast furnace raw material of the right side.

The normal determination part 13 of this embodiment is comprised with rangefinders, such as a laser rangefinder. The top determination part 13 is arrange | positioned above the wall surface 10c side from which the material is guide | induced in the inclination plate 11, and measures the distance to the position of the blast furnace raw material 1 located below, and thus, the top of the mountain ( The height of P) is detected. The laser rangefinder may be arranged in a plurality so as to be arranged in the inclined direction of the inclined plate 11, and the mountain range P may be detected from the detected values of the plurality of laser rangefinders. For example, the distance is measured along the inclined surface of the deposition surface to be formed, and the position where the extension lines of the detected plurality of points intersect with the top bunker 10 wall surface is regarded as the height of the peak portion P of the mountain. In FIG. 1, although the case of two telemeters is illustrated, 3 or more may be sufficient.

The structure of the normal determination part 13 is not limited to this. For example, the relationship between the input amount and the weight of the blast furnace raw material to the top bunker 10 and the height of the peak of the mountain P of the blast furnace raw material 1 deposited is determined in advance from experiment or theory, and the top bunker 10 ), The height of the government P may be determined by estimating the input amount into the tank, the weight of the open-air bunker 10, and the government P of the mountain accumulated from the above relationship.

The inclination-angle adjustment part 14 is a position upwards by the wall surface position of the said top bunker 10 of the same height as the height judged by the top determination part 13, or the margin set in advance from the wall surface position and the wall surface position. The inclination angle θ of the inclined plate 11 is changed to be continuously or intermittently small in accordance with the change in the height determined by the top determination unit 13 so that the blast furnace raw material is guided to the wall surface position located in the range of. .

The margin is at most 1 m. It is because it confirmed that the problem by rebounding and rebounding when colliding with a wall surface in the range within 1 m from the height of the government part P was small. The margin is preferably 0.5 m.

Here, from the experiment or theory, the blast furnace raw material falling and contacting the inclined plate 11 is guided along the inclined plate 11, and the trajectory of the free fall from the inclined plate 11 is obtained in relation to the inclination angle θ. Then, the relationship between the inclination angle θ and the average position where the blast furnace raw material guided by the inclination plate 11 abuts on the wall surface is obtained and stored in the storage unit in a state such as a table or a relational expression.

And the inclination-angle adjustment part 14 calculate | requires the inclination angle (theta) which can guide | induce the blast furnace raw material to the wall surface position of the said top bunker 10 of the same height as determined by the top determination part 13, based on the information of a memory | storage part, The inclination angle θ of the inclination plate 11 is changed so as to obtain the obtained inclination angle θ. Since there is a variation in the induction of blast furnace raw material from the inclined plate 11, for example, a position 10 cm to 20 cm higher than the wall surface position of the top bunker 10 at the same height as that determined by the top determination unit 13. It is preferable to obtain the inclination angle θ aiming at to obtain the blast furnace raw material. The inclination angle may be adjusted continuously at a predetermined sampling time, or may be changed each time the height change of the step P changes by more than a predetermined value.

The inclination-angle adjustment part 14 starts when it determines with the blast furnace raw material more than the initial stage input amount set previously in the top bunker 10 being stored. For example, when the top determination part 13 detects the increase of a raw material layer, it determines with the blast furnace raw material more than initial stage in the top bunker 10 being stored. Moreover, even if it determines with the blast furnace raw material more than an initial loading amount being stored by other means, such as determining the blast furnace raw material more than an initial loading amount by storing the weight of the top bunker 10 and detecting the increase of the weight corresponding to an initial loading amount, do.

Here, the blast furnace raw material thrown in the initial 1/10 or more range among the initial injection amounts of the input amount of a raw material layer is used as the ore raw material which does not contain coke. Since the blast furnace raw material of the area | region put into the top bunker 10 for the first time is discharged | emitted from the top bunker at the earliest, it will be charged in the center of a blast furnace dimensionless radius. On the other hand, it is necessary to improve the reactivity of the ore layer by the mixed coke in the middle of the ore layer having a large amount of ore. From this, it is preferable that the mixed coke be mixed most in the middle of the discharge. This is because it is necessary to reduce the coke mixed at the beginning of discharge. Therefore, it is preferable not to contain mixed coke at the beginning of raw material discharge | release. In this way, in the initial part including the discharge port 10b of the top bunker 10, only the ore raw material is deposited. Also in this case, since storage is performed after contacting the inclined plate 11 once, ore having a rough particle diameter mainly segregates and is stored on the discharge port 10b side. Ore raw material which does not contain coke may be 1/2 of an initial stage feed amount, and also all.

Moreover, the initial angle with respect to the horizontal direction of the inclination-angle (theta) of the inclination board 11 is 45 degree | times. In addition, in this embodiment, when it determines with the inclination-angle (theta) being less than 25 degree | times, charging of the blast furnace raw material to the top bunker 10 is complete | finished. The charging end conditions of the blast furnace raw material may adopt other conditions.

However, when the inclination angle θ is too large, there is a possibility that the material cannot be guided to the wall surface. On the contrary, when the inclination angle θ is too small, the raw material may easily fall from the side of the inclination angle θ by a predetermined amount or more, and the drop speed may not be obtained and the material may not be guided to the wall surface. From this point of view, the inclination angle θ is in the range of 45 degrees to 25 degrees in this embodiment. Moreover, since the inclination angle (theta) becomes small, so that an acid becomes high, in this embodiment, the case where it becomes less than 25 degree is made charging end.

(Movement and others)

In recent years, in the blast furnace operation, the particle size distribution in the furnace is appropriately adjusted, the flow rate distribution in the furnace radial direction of the gas rising in the blast furnace 20 is adjusted, and the air permeability in the furnace and the reduction of the blast furnace raw material and the furnace body. Heat load and the like are in a desired state. Specifically, it is considered that operation in which a large amount of gas flows in the center of the furnace is preferable. In addition, this is called central flow oriented or central flow operation.

Such a flow rate distribution of gas (hereinafter also referred to simply as a gas flow distribution) mainly depends on the thickness ratio of the ore layer and the coke layer formed in the furnace or the particle size distribution in the furnace radial direction adjusted at the time of their charging. Is determined. In particular, in the case of using the bellows-type charging device having the swing chute 21 and arranging the top bunker 10 in parallel, the blast furnace raw material is charged into the top bunker 10, whereby Classified on the slope, ubiquitous by particle size occurs. In short, the blast furnace raw material that has fallen to the right side in the top bunker 10 moves to the discharge port 10b side, which is the center portion away from the drop position, so that fine grains are segregated and deposited on the right wall side of the drop position, and the assembly is discharge port 10b. It segregates to the left side of the side and is deposited.

Thereby, the blast furnace raw material can be sent out from the discharge port 10b of the top bunker 10 in order of granulation, neutrality, and fine grains. In this way, by stacking the granules in the blast furnace 20 for each particle size, it is possible to deposit granules in the center of the blast furnace 20, so that the gas flow distribution with the central flow developed is obtained stably.

Here, when the blast furnace raw material is sent from the top bunker 10 to the slewing chute 21 in the blast furnace 20 disposed below at the time of charging the blast furnace raw material into the blast furnace 20 from the center side, In other words, depositing the blast furnace raw material from the lower side of the mortar on the mortar has no phenomenon such as collapse of the blast furnace raw material than depositing the blast furnace raw material from the upper side of the mortar on the mortar. , The desired deposition shape is obtained. In consideration of this, in the present embodiment, the tip of the swing chute 21 is pivoted while moving in the circumferential direction from the center of the furnace to set the blast furnace raw material (reverse tilt charging).

That is, the reverse side of the turning chute 21 is rotated while gradually tilting from the center of the blast furnace 20 toward the periphery, whereby the sidewall away from the blast furnace raw material falling position of the blast furnace raw material in the top bunker 10 is discharged. The inclined plate 11 is tilted to obtain a predetermined blast furnace raw material particle size distribution. And by sending out to the turning chute 21 similarly to the above, granulation is gathered in the center part of the blast furnace 20, and a fine grain collects in the periphery part.

In addition, although the above description is for obtaining a gas flow distribution in which the central flow is developed, in order to develop the peripheral flow at the intention of the operator, the order of turning while gradually tilting toward the center from the periphery of the blast furnace 20 is described. It is also possible to arrange the assembly on the periphery side by applying tilt loading.

In addition, a plurality of top bunkers are arranged above the blast furnace 20, and blast furnace raw materials of the respective top bunkers 10 are charged into the blast furnace 20 in a predetermined order. The present invention is particularly effective when charging a mixed material.

Here, in order that the top determination part 13 detects the increase of a raw material layer, it is the thing which started control of the inclination plate 11 after the blast furnace raw material more than the initial-loading amount set previously in the top bunker 10 is stored. This is because it is difficult to induce the material toward the government P of the blast furnace raw material deposited.

Example

2, the deposition shape of the general blast furnace raw material in the blast furnace 20 is shown. The stock line of FIG. 2 is a position used as a reference | standard which charges blast furnace raw material, and is a position used as a raw material loading reference plane. 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 at a dimensionless radius. The ore has a particle size of about 1/3 smaller than that of coke, and it is difficult to flow gas, so the reactivity of the ore in this part needs to be improved, and it is considered that it is effective to mix coke in this part. Since the ore 1 is charged toward the dimensionless radius 0 to 1, in order to mix the coke in this part, it is considered that it is effective to discharge the mixed raw material from the discharge initial stage to the middle stage.

3, the top bunker 10 of the comparative example arrange | positioned above the blast furnace 20 is shown. In this top bunker 10, the blast furnace raw material of the part of "1" of the discharge port 10b vicinity is discharged first. In addition, in the comparative example 2, the part of "1" also becomes mixed coke. Subsequently, the blast furnace raw material of the part of "2" located just above the discharge port 10b is discharged, and the part of "3" is discharged after that. Moreover, in the top bunker 10, granulation segregates below the deposition surface according to the particle size of the blast furnace raw material. Here, since the coke charged into the top bunker 10 is larger than the ore, it segregates under the skirt. That is, if coke can segregate to the part of "2" in FIG. 3, it becomes possible to concentrate and charge a mixed raw material in 0.3-0.7 vicinity in a dimensionless radius.

However, when the angle of the inclination plate 11 is not adjusted according to the government part P of the blast furnace raw material deposition surface (upper surface of the deposited blast furnace raw material 1) during one time of blast furnace raw material charging, as shown in FIG. A skirt part is generated also in the part of raw material "3", and the blast furnace raw material which segregates in the part of "3" exists.

On the other hand, in this embodiment, in order to avoid this, the angle of the inclination plate 11 is controlled in accordance with the government part P of the blast furnace raw material deposition surface, and as shown in FIG. 1, the facing surface directly above the discharge port 10b of the blast furnace raw material. The government part P of the blast furnace raw material deposit 1 was made in the wall surface of the (far side), and it controlled so that the skirt part may be formed toward the discharge port 10b.

According to this embodiment, as shown in FIG. 3, it segregates to the part of deposition blast furnace raw material "3" conventionally, the coke charged at the end of discharge | emission is reduced, and the control of the charging position of a mixed raw material becomes more accurate.

Here, since it was found out that the height of the blast furnace raw material loading position from the blast furnace raw material charging surface and the mixing timing when mixing the mixed raw materials with the ore have a great influence on the coke mixing amount, The operation evaluation of 20) was performed.

Here, Inventive Examples 1 to 4 and Comparative Example 2 are examples of the case where the angle of the inclined plate 11 was adjusted in accordance with the step P of the blast furnace raw material deposition surface (upper surface of the deposited blast furnace raw material 1), and compared. Example 1 is a case where the inclination angle of the inclined plate 11 is fixed at 25 degrees.

Further, Inventive Examples 1 to 4 and Comparative Example 1 are examples of slowing down the mixing course mixing timing, and Inventive Examples 1, 2 and 4 and Comparative Example 1 are ore raw materials in which 1/10 of the initial dose is not containing coke. Invention Example 3 is a case where 2/10 of the initial charge amount is an ore raw material containing no coke. Comparative example 2 is an example when there is no part of the ore raw material that does not contain coke.

The relationship of the discharge ratio and mixing ratio in each invention example and a comparative example at this time is shown in FIG. Moreover, the standard deviation of each degree of mixing in each invention example and a comparative example is shown. As can be seen from these, in the invention example, it can be seen that segregation is significantly suppressed as compared with the comparative example. Specifically, it is found that Inventive Example 3 has the smallest segregation, and that of the Comparative Example 4 has the largest segregation. When segregation is suppressed, the coke charged at the end of discharge decreases, and the charging position of the mixed coke can be controlled more accurately.

Table 1 also shows the results of the operation at that time.

As can be seen from Table 1, when Inventive Examples 1 to 4 and Comparative Example 1 are compared, the inclined plate (in accordance with the rise of the blast furnace raw material deposition surface) is compared with the case where the inclined angle of the inclined plate 11 is fixed (Comparative Example 1). Inventive Examples 1 to 4, which changed the inclination angle of 11), showed that the gas utilization rate was improved and the reducing material cost was lowered.

In addition, as can be seen from Inventive Examples 1 to 3 and Inventive Example 4, the charging height from the raw material surface is larger than 1.0 m by suppressing the charging height from the raw material surface to 1.0 m or less as in the invention examples 1 to 3. As compared with the case, it was found that the gas utilization rate was improved and the reducing material cost was lowered. Here, as in Inventive Example 4, when the charging height from the blast furnace raw material charging surface is raised more than 1.0 m, some blast furnace raw materials repel against the wall and spring up, and the part P of the blast furnace raw material deposition in the top bunker 10 becomes smooth. As a result, segregation of the mixed raw materials is suppressed, and as a result, part of the coke is discharged at the end of the blast furnace raw material discharge, so that the amount of coke mixed is uneven, so that the gas utilization rate decreases and the reducing material cost increases.

From these results, it is thought that it is preferable to change the inclination angle of the inclination plate 11 with the raise of a blast furnace raw material deposition surface, and to set the blast furnace raw material loading position to 1 m or less.

Moreover, as can be seen from the comparison between Inventive Examples 1 to 4 and Comparative Example 2, even if the inclination angle of the inclined plate 11 is changed in accordance with the rise of the blast furnace raw material deposition surface, the mixing timing of the mixed raw materials is "0.0" ( Compared with Comparative Example 2), by delaying the mixing timing of the mixed raw materials to 0.1 or more, the coke segregated initially is suppressed and the mixed raw materials can be mixed well in the vicinity of 0.3 to 0.7 at the dimensionless radius. The improvement of utilization rate and the reduction of reducing material cost were confirmed.

In view of the above, by changing the inclination angle of the inclined plate 11 in accordance with the rise of the blast furnace raw material deposition surface and delaying the mixing timing of the mixed raw materials to 0.1 or more, it is possible to improve the gas utilization rate and reduce the reducing material cost. Could know.

Here, FIG. 6 shows a change in the angle of the inclined plate 11 when the discharge ratio of the blast furnace raw material and the charging height from the blast furnace raw material surface are 1 m. In addition, while continuing to load blast furnace raw material into the part in which the wall surface is oblique in the lower part of the top bunker 10, the inclination plate 11 was made constant at 45 degree | times.

As a result, until the discharge ratio was 20%, the angle of the control panel was made constant at 45 degrees, and after that, the discharge ratio was monotonously reduced to 25 degrees as the discharge ratio became 100%. From these, it is preferable that the angle control of the inclination plate 11 monotonously reduces to 45 degrees-25 degrees in the area | region where the blast furnace raw material loading rate is 20% or more.

As described above, the entire contents of Japanese Patent Application No. 2015-108624 (filed on May 28, 2015), to which the present application claims priority, form part of the present disclosure by reference.

Although the description has been made here with reference to a limited number of embodiments, the scope of rights is not limited to them, and modification of each embodiment based on the above disclosure is obvious to those skilled in the art.

1: deposited blast furnace raw material
10: Expedition Bunker
10a: inlet
10b: outlet
10c: wall
11: inclined plate
12: drive unit
13: normal determination unit
14: inclination angle adjustment unit
15: belt conveyor
16: ore raw material
17: coke
20: blast furnace
21: turning suit
P: Government
θ: tilt angle

Claims (5)

As a raw material charging apparatus to the blast furnace for segregating and storing the blast furnace raw material thrown into the blast furnace bunker for charging into the blast furnace,
An inclined sloping plate disposed in the top bunker and receiving the blast furnace raw material introduced into the top bunker and leading to a wall surface in the top bunker;
A normal determination unit that determines, by detection or estimation, the height of the peak of the acid of the blast furnace raw material stored in the top bunker;
If the blast furnace raw material is stored in the said top bunker more than the preset initial input amount, the wall position of the said top bunker of the same height as the height judged by the said normal determination part, or the predetermined margin from the wall position and the wall position It is provided with the inclination-angle adjustment part which changes the inclination-angle of the said inclination plate according to the height determined by the said top determination part so that blast furnace raw material may be guide | induced toward the wall surface position located in the range of an upper position,
The first blast-furnace raw material which is an amount in the range of at least 1/10 of the initial input amount is the ore raw material which does not contain coke, and the initial input amount is a raw material loading to the blast furnace, characterized in that the initial input amount is prescribed by weight Device. The method of claim 1,
The margin is 1 m, the raw material charging device to the blast furnace, characterized in that. The method according to claim 1 or 2,
The blast furnace raw material injected into the said top bunker is a mixed raw material of an ore raw material and coke in the state in which the inclination angle adjustment is performed by the said inclination-angle adjustment part, The raw material charging apparatus to the blast furnace. The method according to claim 1 or 2,
The inclination angle of the inclined plate is 45 degrees to the initial angle of the inclination with respect to the horizontal direction, and when it is determined that the inclination angle is less than 25 degrees, the input of the blast furnace raw material to the top bunker is terminated. Charging device. The method of claim 3, wherein
The inclination angle of the inclined plate is 45 degrees to the initial angle of the inclination with respect to the horizontal direction, and when it is determined that the inclination angle is less than 25 degrees, the input of the blast furnace raw material to the top bunker is terminated. Charging device.

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