JP2005291537A - Sintered raw material charging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a grain size segregating charging device capable of accurately segregating the grain size of a sintered raw material by the fine grain size distribution in the layer thickness direction on the chute lower side. <P>SOLUTION: This charging device is constituted in a screen shape by juxtaposing a plurality of rods 4 substantially parallel to the pallet width direction at an interval, and has a screen-like chute 3 for narrowing the interval between the adjacent rods toward the chute upper side. A diameter of a plurality of rods B on the chute lower side, is formed smaller than a diameter of a plurality of rods A on the chute upper side. Thus, since the rod interval number per unit length increases in the chute longitudinal direction, fine classification can be performed in the chute longitudinal direction. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a raw material charging apparatus for charging a sintered raw material in a state of particle segregation onto a moving sintering pallet in a sintering machine for producing sintered ore used as a blast furnace raw material.

  As a manufacturing facility for sintered ore which is a main raw material of a blast furnace, an endless moving grate type sintering machine such as a Dwytroid type is widely used. In the production of sintered ore using this sintering machine, in general, raw materials charging equipment is used for sintering raw materials (hereinafter simply referred to as “raw materials”) that are granulated by mixing iron ore with coke powder and lime powder. In this way, the surface of the raw material packed layer is flattened by the raw material leveling mechanism and the packing density is made uniform, and then the surface of the raw material packed layer is ignited and subjected to the sintering process. enter. Here, the flatness of the surface of the raw material packed layer and the uniformity of the packing density have a great influence on the quality and yield of the product sintered ore and also on the productivity.

  The conventional sinter production process in the above-mentioned sintering machine will be described more specifically. First, a pseudo-particle raw material (granulated material) of about 5 mm or less is placed on a pallet by a charging chute of the raw material charging device. The raw material filled layer is formed by charging. After this raw material packed layer is leveled by the raw material leveling mechanism as described above, the coke powder contained in the surface layer portion of the raw material packed layer is ignited in an ignition furnace. On the other hand, iron ore is fired from the upper layer to the lower layer while air is sucked from below the pallet with a blower and the coke powder in the raw material packed bed is burned. In such a firing process, good air permeability in the raw material packed bed is ensured, and ensuring uniform air permeability in the width direction and the longitudinal direction of the pallet is an important factor in operation.

  In order to improve the air permeability of the raw material packed layer, it is effective to control the particle size distribution of the raw material in the raw material packed layer, and specifically, a state in which a finer raw material is deposited on the upper layer side. It is preferable to become. As a device for realizing such a particle size distribution, a raw material charging device as shown in FIG. 4 is known (for example, Patent Document 1). This raw material charging apparatus is provided with a screen-like chute 11 for charging particle size segregation, which is inclined downward with respect to the anti-pallet moving direction, below a raw material supply mechanism 10 such as a roll feeder. 11 has a structure in which a large number of rods 12 parallel to the pallet width direction are arranged in parallel at intervals, and the intervals between the rods 12 are narrowed toward the upper side of the chute. The multiple rods 12 are integrally held by a rod holding member (not shown) at a plurality of locations in the pallet width direction so as to maintain a predetermined interval.

According to such a raw material charging apparatus, since the raw material that is discharged from the raw material supply mechanism 10 and slides down on the screen-like chute 11 has a smaller interval between the rods 12 constituting the screen-like chute 11, When falling onto the pallet P through the gap between the rods 12, it is sieved (classified) according to the particle size, and the raw material with a larger particle size is charged to the raw material charging start end side of the pallet P. As a result, the raw material packed layer after charging is in a state where the raw material particle size is segregated finer toward the upper layer side.
Japanese Patent Laid-Open No. 5-1335

  When the raw material is charged on the pallet using the raw material charging device described above, the fine particle size distribution in the thickness direction of the raw material packed layer is as accurate as possible with the original purpose of improving air permeability by particle size segregation. Although it is preferable to segregate well, since this charging device classifies the raw material in the gap of the rod, there is a limit to the accuracy of classification and the accuracy of particle size segregation associated therewith. However, since the dropping speed of the raw material is increased, there is a problem that it is difficult to obtain a fine grain size segregation state as intended.

  Furthermore, the screen-like chute 11 of the raw material charging device obstructs the uniformity of the raw material flow in which the rod holding members holding the rods at a plurality of locations in the pallet width direction flow downward from the gap of the rod 12. As a result, there is a problem that the deposition amount and the charging density of the raw material packed layer are not uniform in the pallet width direction. This will be described with reference to FIG. 5. In FIG. 5, reference numeral 13 denotes a rod holding member that holds the rod group of the screen-like chute 11 at a plurality of locations in the pallet width direction. The raw material flowing down the screen-like chute 11 falls onto the pallet from the gaps between the rods 12, but the raw material flow is divided into both sides by the rod holding member 13 at a place where the rod holding member 13 is present (see FIG. F in the middle shows the flow of the raw material divided by the rod holding member 13). For this reason, the amount of raw material deposited immediately below the rod holding member 13 is smaller than other portions where the rod holding member 13 is not provided, and a groove-like portion e (raw material deposition defect portion) is formed in the surface layer portion of the raw material filled layer S. Will be formed. Although the surrounding raw material flows into the groove portion e to some extent during the formation process, the amount of the raw material is not sufficient due to the short falling distance of the raw material. As a result, a raw material deposition layer having a low raw material filling density, that is, a low density filling region is generated below the groove portion e, and such a low raw material filling density region is also eliminated by the raw material leveling mechanism. It is not possible.

  In the low-density filling region, the ventilation resistance is smaller in the other regions (deposition layer region below the flat portion other than the groove portion e), and there is a variation in the ventilation resistance in the pallet width direction inside the raw material layer. Arise. When such a variation in ventilation resistance increases, air suction concentrates in the low-density filling region where the ventilation resistance is relatively small, so that the combustion speed of the coke powder in the combustion zone increases locally, An unburned part is generated in a region other than the low density filling region, and firing is delayed. As a result, problems such as a decrease in yield and quality of the product sintered ore and an increase in the basic unit of coke occur, and the productivity of the sintered ore also decreases.

Accordingly, an object of the present invention is to accurately segregate the sintered raw material with a fine grain size distribution in the layer thickness direction in the raw material charging apparatus for charging the sintered raw material onto the pallet in the grain thickness segregated state in the layer thickness direction. An object of the present invention is to provide a charging device that can be used.
Another object of the present invention is to provide a charging device capable of obtaining a uniform raw material filling density in the pallet width direction by minimizing the formation of the low density filling region by the rod holding member for holding the screen chute rod. Is to provide.

In order to solve the above-mentioned problems, the present inventor has studied the structure of a screen-like chute comprising a plurality of rods and a rod holding member that holds these rods integrally in the chute longitudinal direction. Got.
(1) For the problem that the accuracy of the particle segregation state tends to decrease on the lower side of the chute, it is effective to make the diameter of the multiple rods on the lower side of the chute smaller than the diameter of the multiple rods on the upper side of the chute It turned out that. This is because even if the rod interval is the same, if the rod diameter is small, the number of rod intervals per unit length in the chute longitudinal direction increases, and fine classification in the chute longitudinal direction becomes possible.

 (2) In order to prevent the formation of a low-density filling area by the rod holding member as much as possible and to ensure a uniform raw material filling density in the pallet width direction, the rod holding member (pallet raw material charging) The number of installed rod holding members located above the portion may be reduced. However, if the number of rod holding members is reduced, the rods bend due to the weight and impact of the raw material falling on the chute, and the rod spacing is distorted, making it impossible to classify accurately. As a result, the particle size segregation charging itself is hindered. In order to prevent such bending of the rod, the rod diameter may be increased. However, if the rod diameter is simply increased, the size and weight of the chute are greatly increased, which becomes impractical. Accordingly, as a result of examining the structure of the chute in view of these points, it has been found that the rods constituting the chute have different strengths depending on their positions in the chute longitudinal direction. Specifically, the rod on the upper side of the chute needs to have a certain diameter so as not to bend because a large amount of raw material passes through it. Since the passing amount is small, it has been found that the diameter does not have to be increased toward the upper side of the chute. This reduces the diameter of the rod on the lower side of the chute to be smaller than the diameter of the rod on the upper side of the chute, thereby increasing the weight and size of the entire chute and without impairing the original function of the chute. It was found that the number of installations can be reduced.

The present invention has been made on the basis of the above findings, and the features thereof are as follows.
[1] A raw material supply mechanism for supplying a sintered raw material on a pallet, and a chute for charging the sintered raw material supplied from the raw material supply mechanism into a state of particle size segregation in the layer thickness direction on the pallet. And a screen-like chute that is inclined downward with respect to the anti-pallet moving direction, and the screen-like chute is arranged by arranging a plurality of rods substantially parallel to the pallet width direction in parallel at intervals. In the charging apparatus of the sintering raw material having a configuration in which the interval between adjacent rods or / and the interval between rod groups composed of a plurality of adjacent rods is narrowed toward the upper side of the chute,
A sintered raw material charging apparatus, wherein the diameter of the plurality of rods on the lower side of the chute is smaller than the diameter of the plurality of rods on the upper side of the chute.
[2] In the charging device according to [1], the screen-like chute has a structure in which a plurality of rods are integrally held in the chute longitudinal direction by a rod holding member, and is positioned above the raw material charging portion of the pallet. The apparatus for charging a sintered material, wherein the number of rod holding members installed in the chute width direction is 1 or 2.

[3] In the charging device according to [1] or [2] above, the diameter of 20 to 50% of the rods on the lower side of the chute, including the lowermost rod of the chute among all the rods constituting the screen-like chute. Is made smaller than the diameter of the rod on the upper side of the chute.
[4] In the charging device according to [3], the charging raw material charging device is characterized in that the diameter of the rod on the lower side of the chute is 60 to 80% of the diameter of the rod on the upper side of the chute.
[5] In the charging device according to [1] or [2], the diameter of each rod constituting the screen-like chute and / or the diameter of each rod group composed of a plurality of adjacent rods is set on the upper side of the chute. A sintering raw material charging device characterized in that it is gradually reduced from the lower side to the lower side.

According to the charging device of the first aspect of the present invention, since the sintering raw material can be classified with high accuracy on the lower side of the chute, the particle size segregation can be accurately performed with a fine particle size distribution in the layer thickness direction of the raw material packed layer. The effect of particle size segregation charging can be enhanced.
According to the invention of claim 2, in addition to the above effects, the number of rod holding members constituting the screen-like chute without increasing the size and size of the chute and without impairing the original classification function of the chute Therefore, the formation of the low density filling region in the raw material packed layer is suppressed as much as possible, and a uniform raw material filling density in the pallet width direction can be obtained. As a result, the air permeability in the pallet width direction can be made uniform, and a high-quality product sintered ore can be manufactured with high yield and productivity.

1 and 2 show an embodiment of a charging apparatus for a sintered raw material (hereinafter simply referred to as “raw material”) according to the present invention. FIG. 1 is a side view showing a screen-like chute in a longitudinal section. FIG. 2 is a plan view showing a state in which the raw material supply mechanism is omitted.
In the figure, 1 is a roll feeder constituting a part of the raw material supply mechanism, 2 is also an auxiliary roll for buffering the raw material, and 3 is a state in which the raw material supplied from the raw material supply mechanism is segregated on the pallet in the layer thickness direction. It is a screen-like chute for charging (filling). In FIG. 2, P is a pallet passing under the screen-like chute 3, and S is a raw material packed layer formed on the pallet.

  The screen-like chute 3 (hereinafter simply referred to as “chute 3”) is provided at a position almost directly below the roll feeder 1 and inclined downward with respect to the anti-pallet moving direction. A surge hopper (not shown) having a lower end opened and having a raw material discharge gate is disposed at the upper part of the roll feeder 1, and the raw material is discharged from the raw material discharge gate by the rotation of the roll feeder 1. The raw material is once dropped on the auxiliary roll 2 and buffered, and then supplied to the upper end of the chute 3 by the rotating auxiliary roll 2. The basic configuration itself is the same as that of the conventional apparatus.

The main body of the chute 3 includes a plurality of rods 4 that are substantially parallel to the pallet width direction and arranged in parallel at intervals, and a rod holding member 5 that integrally holds the plurality of rods 4 in the chute longitudinal direction. It is configured. The chute 3 is configured such that the gap w between adjacent rods becomes narrower toward the upper side of the chute. The gap between the rods may be narrowed sequentially for each gap between the adjacent rods 4, or a plurality of adjacent rods may be made into one group and gradually narrowed for each gap between the rod groups. You may do it.
The charging device of the present invention is characterized in that the diameter of the plurality of rods 4 on the lower side of the chute is smaller than the diameter of the plurality of rods 4 on the upper side of the chute. Of the 36 rods, including the rod 4 at the bottom of the chute, the diameter of the rod 4 (rod group B) on the lower side of the chute (1/3) (about 33%) (12 rods) The diameter of the side rod 4 (rod group A) is about 25% smaller.

The number and range of the rods 4 (rod group B) on the lower side of the chute for reducing the rod diameter are not particularly limited. However, in consideration of prevention of rod deflection, chute weight, etc. Of the rods, it is preferable to target 20 to 50%, preferably 25 to 40% of the rods 4 including the rod 4 at the bottom of the chute. The total number of rods is not particularly limited, but is generally about 30 to 60.
Further, the diameter of the rod 4 on the lower side of the chute is not particularly limited. However, in consideration of prevention of rod deflection and the weight of the chute, generally, the diameter is about 60 to 80% of the diameter of the rod 4 on the upper side of the chute. It is preferable. Examples of the diameter of the rod 4 on the lower side and the upper side of the chute include a diameter of the rod on the lower side of the chute: 20 to 30 mm and a diameter of the rod 4 on the upper side of the chute: 12 to 24 mm.

In the charging apparatus of the present invention, various conditions can be adopted for the condition that the diameter of the plurality of rods 4 on the lower side of the chute is smaller than the diameter of the plurality of rods 4 on the upper side of the chute. In addition to the case where the rod diameter is changed in two steps on the upper and lower sides of the chute as in the form, for example, the diameter of each rod 4 constituting the chute 3 and / or each rod group composed of a plurality of adjacent rods 4 The rod diameter may be gradually decreased from the upper side of the chute to the lower side. Specifically, the following forms can be adopted.
(1) The diameter of each rod 4 constituting the chute 3 is gradually reduced from the upper side of the chute to the lower side.
(2) Each rod 4 constituting the chute 3 is divided into three or more rod groups, and the rod diameters of these rod groups are sequentially reduced from the upper side to the lower side of the chute.
In addition to the above (1) and (2), various forms can be adopted.

The rod holding member 5 is formed of an elongated plate-like body, and a plurality of rod insertion holes 50 are provided through the longitudinal direction at appropriate intervals. The rods 4 are inserted through the rod insertion holes 50, so that the plurality of rods 4 are integrally held in the chute longitudinal direction. Each rod holding member 5 has connecting portions 51 and 52 at its upper and lower ends, and is held by a structural member (not shown) via these connecting portions 51 and 52 so that the entire chute including the rod 4 can be obtained. Is supported by the structural member.
In the present embodiment, rod holding members 5a ₁ and 5a ₂ are respectively provided at positions on both sides of the pallet deviated from above the raw material charging portion of the pallet P, and the pallet is located at an intermediate position between them, that is, at the center in the pallet width direction. A rod holding member 5b positioned above the P raw material charging portion is provided. That is, the rod holding member 5b is provided only at one position above the raw material charging portion of the pallet P where the raw material packed layer S is formed.
For the reasons described above, the number of rod holding members 5 positioned above the raw material charging portion of the pallet P on which the raw material packed layer S is formed is preferably as small as possible. For example, FIG. 5b ₁ , 5b ₂ ), it is preferable to have at most two places.

The plurality of rods 4 constituting the chute 3 need to be fixedly held by the rod holding members 5a ₁ and 5a ₂ at least at both ends of the rod, but the material (attachment) adhering to the rod surface is rod-held. In order to scrape off by the member, the rod 4 may be slidable with respect to the rod holding member 5b at the intermediate portion. That is, the rods 4 whose both ends are fixedly held by the rod holding members 5a ₁ and 5a ₂ are slidably inserted into the rod insertion holes 50 of the rod holding member 5b at the intermediate portion, and the plurality of rods 4 and both ends thereof are inserted. The rod holding members 5a ₁ and 5a ₂ that hold the rod can be reciprocated in the pallet width direction by the moving mechanism. In such a structure, the rod 4 can be scraped off by the rod holding member 5b by sliding the rod 4 with respect to the rod holding member 5b at an appropriate time interval.
In the case of the above structure, instead of moving all the rods 4 constituting the chute 3 integrally, the plurality of rods 4 are divided into two or more rod groups, and both ends of each rod group are held by the rods. The members 5a ₁ and 5a ₂ may be fixedly held, and may be configured to be slidable with respect to the intermediate rod holding member 5b for each rod group.

Next, the effect of the charging device of the present invention will be described by taking the above embodiment as an example.
Fig. 3 shows the classification of raw materials by the rod group on the lower side of the chute of the charging device in comparison with the device of the present invention (Fig. 3 (a)) and the conventional device (Fig. 3 (b)). , K _{1 to} K ₄ indicate the flow of the raw material falling from the gaps between the rods 4 and 12. As can be seen from the figure, when the rod diameter is reduced as in the device of the present invention, the number of rod gaps per unit length in the chute longitudinal direction increases even if the rod gap is the same as the conventional device. Fine classification of raw materials in the longitudinal direction of the chute is possible.

Further, in the charging device of the present invention, the diameter of the plurality of rods 4 on the lower side of the chute is made smaller than the diameter of the plurality of rods 4 on the upper side of the chute without increasing the size and weight of the chute 3. In addition, the number of the rod holding members 5 constituting the chute 3 can be reduced without impairing the original classification function of the chute.
Therefore, it is possible to minimize the formation of the groove portion (groove portion e shown in FIG. 5) in the surface layer of the raw material filling layer and the formation of the low density filling region thereby, and uniform raw material filling in the pallet width direction Density can be obtained. As a result, the air permeability in the pallet width direction can be made uniform, and a high-quality product sintered ore can be manufactured with high yield and productivity.

The side view which shows one Embodiment of the charging device of the sintering raw material which concerns on this invention in the state which carried out the longitudinal cross-section of the screen-like chute | shoot The top view which shows the charging device shown in FIG. 1 in the state which abbreviate | omitted the raw material supply mechanism Explanatory drawing which compared the classification of the raw material by the rod group on the lower side of the chute of the charging device in comparison with the device of the present invention (FIG. 3A) and the conventional device (FIG. 3B) Explanatory drawing which shows the conventional charging equipment and the raw material charging situation by this Explanatory drawing which shows the raw material charging situation by the screen-like chute of the conventional charging device, and the cross section of the raw material packed bed

Explanation of symbols

1 Roll Feeder 2 auxiliary roll 3 screen-like chute 4 rods _{5,5a 1, 5a 2, 5b,} 5b 1, 5b 2 rod holding member 50 rod insertion holes 51, 52, connecting portions A, B rod group

Claims (5)

A raw material supply mechanism for supplying a sintered raw material on the pallet, and a chute for charging the sintered raw material supplied from the raw material supply mechanism into a state of particle size segregation in the layer thickness direction on the pallet, A screen-like chute that is inclined downward with respect to the direction of movement of the pallet, and the screen-like chute is configured in a screen shape by paralleling a plurality of rods substantially parallel to the pallet width direction at intervals. And a sintering raw material charging device having a configuration in which the interval between adjacent rods or / and the interval between rod groups consisting of a plurality of adjacent rods is narrowed toward the upper side of the chute,
A sintered raw material charging apparatus, wherein the diameter of the plurality of rods on the lower side of the chute is smaller than the diameter of the plurality of rods on the upper side of the chute.   The screen-like chute has a structure in which a plurality of rods are integrally held in the chute longitudinal direction by a rod holding member, and the number of rod holding members positioned above the raw material charging portion of the pallet is 1 in the chute width direction. The charging apparatus for sintering raw materials according to claim 1, wherein the charging apparatus is a sintering raw material.   Of all the rods constituting the screen-like chute, the diameter of 20-50% of the rods on the lower side of the chute including the lowermost rod of the chute is made smaller than the diameter of the rod on the upper side of the chute. The charging apparatus of the sintering raw material according to claim 1 or 2.   4. The apparatus for charging a sintering material according to claim 3, wherein the diameter of the rod on the lower side of the chute is 60 to 80% of the diameter of the rod on the upper side of the chute.   3. The diameter of each rod constituting the screen-like chute and / or the diameter of each rod group composed of a plurality of adjacent rods are sequentially reduced from the upper side to the lower side of the chute. The charging apparatus of the sintering raw material as described in 2.

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