JP2015224390A - Granulation installation for sintered ore - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a granulation installation for sintered ores which gives an appropriate grain size distribution even when fine ore is used and can keep and improve the productivity of sintered ores simply and effectively.SOLUTION: A stirring crusher 30A is arranged at a segregation position 24 of coarse grains and includes a rotation shaft 31 nearly in parallel with the rotation shaft of a disk 21 and a head part 32A attached to the rotation shaft 31. The head part 32A has a rod-like fixation member 33A fixed to the tip of the rotation shaft 31 and a rod-like stirring blade 34A which is attached to the fixation member 33A and extends downward. The stirring blade 34A including the fixation member 33A is caused to come in contact with a sintering raw material 1 during granulation and pellets 2 after granulation by adjusting the height position of the stirring crusher 30A, while the rotation shaft 31 is prevented from coming in contact with them.

Description

  The present invention relates to a granulation facility for sintered ore that granulates a sintered raw material to obtain a sintered raw material granulated product (pellet).

  Generally, in the iron making process, the powdered ore that is the raw material for sintering is mixed with the limestone powder raw material and other auxiliary raw materials, and the drum mixer (drum granulator equipped with a cylindrical rotating body) or disc pelletizer (dish) A disk-type granulator equipped with a rotating body in the form of a granule while adding water to form a sintered raw material granulated product (pellet), which is then sintered with a sintering machine as a sintered ore. Used in blast furnace. This sintered raw material granulated product is obtained by attaching a powder having a diameter of 1 mm or less to a core having a diameter of several millimeters, and is called “pseudo particle”.

  Due to recent raw material supply circumstances, there is an increasing need to use fine ores (average diameter of about 40 to 150 μm) such as iron-making dust and fine ore having a smaller particle size than conventional powder ores (average diameter of about 1 to 3 mm). ing. In this case, in the conventional granulation method, coarse “adhesion particles” with weak strength in which fine powders adhere to each other increase, the ratio of pseudo particles decreases, uniform granulated material is not formed, and the productivity of sintered ore There is a problem that cannot be maintained.

  Therefore, as an improvement plan for the conventional granulation method, Patent Document 1 discloses that a lime slurry is added to a part of a sintering raw material, and then granulated by a high-speed stirring mixer, and the remainder of the sintering raw material is a primary drum mixer. A method has been proposed in which these sintered raw materials are finely adjusted with a secondary drum mixer to enhance the granulation.

  In Patent Document 2, the sintering raw material is classified into a fine-grained sintering raw material and a coarse-grained sintering raw material by classification, and the fine-grained sintering raw material is conditioned and granulated with a high-speed mixer, and then coarsely divided. There has been proposed a method of granulating a mixture of granulated sintered raw materials.

  Further, in Patent Document 3, by introducing an Eirich mixer (agitating blade) into a granulating apparatus, even a sintered raw material containing fine powder and difficult-to-granulate particles can be simulated with simple equipment. Methods have been proposed that allow the particles to be produced.

JP-A-10-121153 JP 2004-360002 A JP 2002-317228 A

  However, in the case of the method of Patent Document 1, an increase in operating cost and equipment cost is unavoidable due to the use of three mixers: a high-speed stirring mixer, a primary drum mixer, and a secondary drum mixer.

  Further, in the case of the method of Patent Document 2, the route is complicated because it is classified at the time of transportation, and an extra binder for pre-granulating fine particles is required.

  In the case of the method of Patent Document 3, moisture is oozed out at a low speed at the contact portion between the stirring blade and the particle at the time of granulation for increasing the strength, so that the adhesion of the particle to the stirring blade side is increased and maintenance is performed. There is a problem that is difficult. Moreover, since the rotation speed of the stirring blade is restricted by the moisture state of the sintering raw material, there is a problem that coarse particles are generated by low-speed rotation.

  The present invention has been made in view of the above circumstances, and even when fine ore is used, an appropriate particle size distribution is obtained, and the productivity of sintered ore is easily and effectively maintained and improved. An object of the present invention is to provide a granulation facility for sintered ore.

  In order to solve the above problems, the present invention has the following features.

[1] A granulation facility for granulating a sintered raw material mainly composed of powdered iron ore into pellets,
A granulator equipped with a dish-like or cylindrical rotating body, and an agitation crushing device for agitating and crushing the sintered raw material during granulation and / or pellets after granulation in the granulator,
The stirring and crushing apparatus includes a rotating shaft and a stirring and crushing member attached to the rotating shaft, and the rotating shaft does not contact the sintered raw material during the granulation and / or the pellet after granulation. Sinter ore granulation equipment.

  [2] The granulation facility for sintered ore according to [1], wherein the stirring and crushing member is at least one rod-like member or at least one plate-like member.

  [3] The granulation of sintered ore according to [1] or [2], wherein the stirring crushing device is installed so that a rotating shaft thereof is substantially parallel to a rotating shaft of the rotating body. Facility.

  [4] The sintered ore according to any one of [1] to [3], wherein the rotation direction of the rotation shaft of the stirring and crushing device is opposite to the rotation direction of the rotating body. Granulation equipment.

  [5] The sintered ore granulation facility according to the above [1] or [2], wherein the stirring crushing device is installed so that a rotation axis thereof is substantially horizontal.

  In the present invention, even when fine ore is used, an appropriate particle size distribution can be obtained, and the productivity of sintered ore can be easily and effectively maintained and improved.

It is a figure which shows a disk pelletizer. It is a figure which shows Embodiment 1 of this invention. It is a figure which shows the head part in Embodiment 1 of this invention. It is a figure which shows Embodiment 2 of this invention. It is a figure which shows the head part in Embodiment 2 of this invention. It is a figure which shows Embodiment 3 of this invention. It is a figure which shows the head part in Embodiment 3 of this invention. It is a figure which shows the particle size distribution of the granulated material in the Example of this invention. It is a figure which shows the productivity of the sintered ore in the Example of this invention.

  Embodiments of the present invention will be described with reference to the drawings.

  The inventors mixed powder ore, fine ore, limestone powder raw material, and other auxiliary raw materials that are sintering raw materials, and performed granulation while adding water with a disk pelletizer (or drum mixer). Experienced a particle size distribution that contains a large amount of coarse particles (coarse particles with weak strength with fine particles adhering), which reduces the proportion of pseudo particles in the appropriate particle size range and deteriorates the air permeability of the sintering machine. did.

  FIG. 1 is a view showing a disk pelletizer. FIG. 1A is a schematic top view of the disk pelletizer viewed from the bottom, and FIG. 1B is a longitudinal sectional view. The disk pelletizer 20 includes a disk (a dish-shaped rotating body) 21 and rotates in the direction of an arrow 22. Thereby, the sintered raw material 1 and the sintered raw material granulated material (pellet) 2 mainly flow in the direction 23 of the arrow.

  Then, when the inside of the disk pelletizer 20 is observed, there is a characteristic in the position where the coarse particles are present, and in a plan view, it is an area indicated by 24 in FIG. 1 and the surface layer of pellet 2).

  Therefore, the present inventors place a stirring crushing device (rotary shaft, stirring blade) at the segregation position 24 of the coarse particles, and selectively pulverize the coarse particles to regulate the sintered raw material granulated product. Thought to do.

  Specifically, it is necessary to appropriately crush the coarse particles generated in the granulation process, but when the coarse particles are crushed by the contact force between the coarse particles and the stirring blade, fine particles are generated, and the fine particles are stirred and crushed. It is necessary to prevent the rotating shaft from coming into contact with the particle layer (sintered raw material layer). If fine powder particles adhere to the rotating shaft, it will hinder the sizing of the pellet (sintered raw material granulated product). This point is not considered at all in the prior art (Patent Documents 1 to 3, etc.).

  Therefore, in the embodiment of the present invention, the granulation equipment for granulating a sintered raw material mainly composed of powdered iron ore into pellets is a disk pelletizer (a granulator equipped with a dish-like rotating body). And a stirring and crushing device for stirring and crushing the sintered raw material being granulated and the pellets after granulation by the granulator, the stirring and crushing device comprising a rotating shaft and a stirring blade attached to the rotating shaft The stirring blade is in contact with the sintered raw material during granulation and the pellet after granulation, and the rotating shaft is not in contact with the material.

  Hereinafter, Embodiments 1 to 3 of the present invention will be described.

[Embodiment 1]
FIG. 2 is a diagram showing Embodiment 1 of the present invention. 2A is a schematic top view corresponding to FIG. 1, and FIG. 2B is a longitudinal sectional view. FIG. 3 is an enlarged view of a main part of FIG. FIG. 3A is a schematic top view, and FIG. 3B is a schematic front view.

  As shown in FIGS. 2A and 2B, in the first embodiment, the granulation facility 10 includes a disk pelletizer 20 (disk 21) and a stirring and crushing device 30 (30A).

  The stirring and crushing device 30A is installed at the coarse grain segregation position 24, and has a rotating shaft 31 substantially parallel to the rotating shaft of the disk 21 (substantially perpendicular to the rotating surface of the disk 21), and the rotating shaft. And a head portion 32 (32 </ b> A) attached to 31.

  As shown in FIGS. 3A and 3B, the head portion 32A includes a rod-shaped fixing member 33A fixed to the tip of the rotating shaft 31, and a rod-shaped extending downwardly attached to the fixing member 33A. A stirring blade 34 (34A) is provided.

  Then, by adjusting the height position of the stirring crushing device 30A, the stirring blade 34A (including the fixing member 33A) is in contact with the sintered raw material 1 during granulation and the pellet 2 after granulation, The rotating shaft 31 is not in contact.

  As described above, since coarse particles are present in the surface layer of the particle layer, the stirring blade 34A needs to have a length including the surface layer of the particle layer, but it is not necessary to stir the entire particle layer. On the other hand, the rotation shaft 31 needs to be separated from the surface of the particle layer so that fine powder particles do not adhere to the rotation shaft 31, but if it is too far away, the crushing efficiency of the coarse particles decreases. Considering the above, the length of the stirring blade 34A is preferably ¼ to 3 times the depth of the disk 21 of the disk pelletizer 20. Further, the stirring crushing device 30A is installed so that the stirring blade 34A reaches a depth of 1/3 or less from the surface of the particle layer in the region where the coarse particles are present.

  This prevents fine particles from adhering to the rotating shaft 31 and allows the pellets (sintered raw material granulated product) to be smoothly sized.

[Embodiment 2]
FIG. 4 is a diagram showing Embodiment 2 of the present invention. 4A is a schematic top view corresponding to FIG. 1, and FIG. 4B is a longitudinal sectional view. FIG. 5 is an enlarged view of a main part of FIG. FIG. 5A is a schematic top view, and FIG. 5B is a schematic front view.

  As shown in FIGS. 4A and 4B, in the second embodiment, the granulation equipment 10 includes a disk pelletizer 20 (disk 21) and a stirring and crushing device 30 (30B).

  The stirring and crushing device 30B is installed at the coarse grain segregation position 24, and has a rotating shaft 31 substantially parallel to the rotating shaft of the disk 21 (substantially perpendicular to the rotating surface of the disk 21), and the rotating shaft thereof. And a head portion 32 (32 </ b> B) attached to 31.

  As shown in FIGS. 5A and 5B, the head portion 32B includes a flat plate-like fixing member 33B fixed to the tip of the rotating shaft 31, and a downwardly attached plate attached to the fixing member 33B. Shaped stirring blade 34 (34B).

  Then, by adjusting the height position of the stirring crushing device 30B, the stirring blade 34B (including the fixing member 33B) is in contact with the sintered raw material 1 during granulation and the pellet 2 after granulation, The rotating shaft 31 is not in contact.

  As described above, since coarse particles are present in the surface layer of the particle layer, the stirring blade 34B needs to have a length including the surface layer of the particle layer, but it is not necessary to stir the entire particle layer. On the other hand, the rotation shaft 31 needs to be separated from the surface of the particle layer so that fine powder particles do not adhere to the rotation shaft 31, but if it is too far away, the crushing efficiency of the coarse particles decreases. Considering the above, the length of the stirring blade 34B is preferably ¼ to 3 times the depth of the disk 21 of the disk pelletizer 20. Further, the stirring crushing device 30B is installed so that the stirring blade 34B reaches a depth within 1/3 from the surface of the particle layer in the region where the coarse particles are present.

  This prevents fine particles from adhering to the rotating shaft 31 and allows the pellets (sintered raw material granulated product) to be smoothly sized.

[Embodiment 3]
FIG. 6 is a diagram showing Embodiment 3 of the present invention. 6A is a schematic top view corresponding to FIG. 1, and FIG. 6B is a longitudinal sectional view. FIG. 7 is an enlarged view of a main part of FIG. FIG. 7A is a schematic top view, and FIG. 7B is a schematic front view.

  As shown in FIGS. 6A and 6B, in the third embodiment, the granulation equipment 10 includes a disk pelletizer 20 (disk 21) and a stirring and crushing device 30 (30C).

  The stirring and crushing device 30C is installed at the coarse particle segregation position 24, and has a rotating shaft 31 that is substantially horizontal and a head portion 32 (32C) attached to the rotating shaft 31.

  And as shown to Fig.7 (a), (b), 32 C of head parts are equipped with the plate-shaped stirring blade 34 (34C (34C1-34C4)) attached to the front-end | tip of the rotating shaft 31, and the middle. .

  Then, by adjusting the height position of the stirring crushing device 30C, the stirring blade 34C is in contact with the sintered raw material 1 during granulation and the pellet 2 after granulation so that the rotating shaft 31 is not in contact. It has become.

  As described above, since coarse particles are present in the surface layer of the particle layer, the stirring blade 34C needs to have a length including the surface layer of the particle layer, but it is not necessary to stir the entire particle layer. On the other hand, the rotation shaft 31 needs to be separated from the surface of the particle layer so that fine particles do not adhere to the rotation shaft 31, but if it is too far away, the crushing efficiency of coarse particles decreases. Considering the above, it is preferable that the length of the stirring blade 34 </ b> C is ¼ to 3 times the depth of the disk 21 of the disk pelletizer 20. Further, the stirring and crushing device 30C is installed so that the stirring blade 34C reaches a depth of 1/3 or less from the surface of the particle layer in the region where the coarse particles are present.

  This prevents fine particles from adhering to the rotating shaft 31 and allows the pellets (sintered raw material granulated product) to be smoothly sized.

  Here, in the first to third embodiments, as described above, since the coarse particles float on the surface of the particle layer, the stirring blade 34 (34A, 34B, 34C) is brought into contact with the bottom surface of the disk 21. There is no need to make them, and a sufficient crushing effect can be obtained within 1/4 of the maximum depth of the disk 21. Further, the number of the stirring crushing devices 30 (30A, 30B, 30C) is not limited to one, and a plurality of them may be used.

  Further, the contact force required for crushing varies depending on the particle size, and the crushing force increases in proportion to the contact speed. Therefore, it is desirable to install the stirring and crushing device 30 so that the rotation direction 35 of the stirring blade 34 is opposite to the moving direction 23 of the particles. That is, in the stirring and crushing devices 30A and 30B, it is desirable to install the stirring blades 34A and 34B so that the rotation direction 35 of the stirring blades 34A and 34B is opposite to the rotation direction 22 of the disk 21. It is desirable to set 35 so that the sintering raw material 1 and the pellets 2 are pushed upward in the inclination of the disk 21.

  Further, the number of the stirring blades 34 may be one or more. However, when the volume occupied by the stirring blades 34 in the rotation range of the stirring blades 34 is excessively increased, the inflow of the sintering raw material is reduced and the crushing effect is also reduced. The number of the stirring blades 34 is preferably 3 to 12 and more preferably 4 to 8 for each head portion 32 (32A, 32B, 32C).

  The coarse grain segregation position is not significantly different from the position 24 shown in FIG. 1 as long as the tilt angle and the rotational speed of the disk 21 are in a range suitable for operation. However, if the details of the coarse grain segregation position 24 are confirmed by visual observation, video or camera video recording, or other methods, the position with the largest coarse grain can be specified and the stirring blade 34 can be arranged.

  In this way, the agitation blade 34 is disposed at the coarse segregation position 24, and the coarse particles are weakly adhered particles in which fine powder is aggregated and are easily broken, so the coarse particles are selectively crushed. The The crushed particles remain in the disk 21 and are adjusted to an appropriate particle size through the granulation process again. On the other hand, the strength of particles that are not crushed increases due to compaction.

  Thus, by pulverizing the coarse particles simultaneously with the granulation, the pellets (sintered raw material granulated product) can be easily sized without increasing the granulation step.

  In addition, although the case where the disk pelletizer (disk type granulator provided with the plate-shaped rotary body) was used was described here, the drum mixer (drum type granulator provided with the cylindrical rotary body) was used. Even when it is used, it can be similarly implemented.

  In order to confirm the effect of the present invention, a granulation test of a sintered raw material was performed based on the above first to third embodiments of the present invention. Table 1 shows the specifications and operating conditions of the disk pelletizer 20 at that time. Table 2 shows the composition of the sintering raw material. As shown in Table 2, 17% by mass of fine ore D was blended.

  And as a comparative example, the sintering raw material was granulated without using the stirring and crushing device 30.

  On the other hand, as the inventive examples 1, 2, and 3, the sintered raw material was granulated based on the above-described Embodiments 1, 2, and 3, respectively. Table 3 shows the specifications of the stirring blades 34 and the number of the stirring crushing devices 30 installed.

  About each example, about 2 kg of samples were taken 10 times every 3 minutes, and the result of having investigated a particle size distribution (total of 10 times) is shown in FIG.

  It can be seen that Invention Example 1, Invention Example 2, and Invention Example 3 have less coarse and fine particles and a larger proportion of sieve particles of 1-4.75 mm (appropriate particle size range) as compared with Comparative Examples.

  In addition, the productivity when the obtained sintered raw material granulated material is sintered (the production amount per unit time of a sintered ore having an appropriate particle size and strength) is standardized as Comparative Example 1. The rate index is shown in FIG.

  It can be seen that the present invention example 1, the present invention example 2 and the present invention example 3 in which the ratio of the particle size is in the proper range are higher in productivity than the comparative example 1.

  Thus, in the present invention, even when fine ore is blended, coarse particles can be crushed simultaneously with granulation using a stirring blade with little differential particle adhesion, and appropriate strength and particle size can be obtained. It was found that the distribution can be realized and the productivity of sintered ore can be maintained.

1 Sintered raw material 2 Pellet (sintered raw material granulated product)
10 Granulating equipment 20 Disc pelletizer (disc type granulator)
21 Disc 22 Rotating direction of disc 23 Main flow direction of sintering raw material 24 Segregation position of coarse particles 30 (30A, 30B, 30C) Stirring crusher 31 Rotating shaft 32 (32A, 32B, 32C) Head portion 33 (33A, 33B) Fixing member 34 (34A, 34B, 34C) Stirring blade (stirring crushing member)
35 Stirring blade rotation direction

Claims (5)

A granulation facility for granulating a sintered raw material mainly composed of powdered iron ore into pellets,
A granulator equipped with a dish-like or cylindrical rotating body, and an agitation crushing device for agitating and crushing the sintered raw material during granulation and / or pellets after granulation in the granulator,
The stirring and crushing apparatus includes a rotating shaft and a stirring and crushing member attached to the rotating shaft, and the rotating shaft does not contact the sintered raw material during the granulation and / or the pellet after granulation. Sinter ore granulation equipment.   The granulation facility for sintered ore according to claim 1, wherein the stirring and crushing member is at least one rod-like member or at least one plate-like member.   The granulation facility for sintered ore according to claim 1 or 2, wherein the rotating shaft of the stirring and crushing device is installed so as to be substantially parallel to the rotating shaft of the rotating body.   The granulation facility for sintered ore according to any one of claims 1 to 3, wherein a rotation direction of a rotation shaft of the stirring and crushing device is opposite to a rotation direction of the rotating body.   The granulation facility for sintered ore according to claim 1, wherein the stirring crusher is installed so that a rotation shaft thereof is substantially horizontal.

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