JPH0523568A - Raw material granulation and its device - Google Patents

Abstract

PURPOSE:To improve granulation properties and processing capability without kneading for pressure-tight plasticizing process to secure the durability of a main machine system and deal with the vibration of a bracket when a raw material is granulated. CONSTITUTION:A raw material granulation device is composed of two functional parts; one is a stirring blender which adds an adequate amount of water for granulating a raw material depending on the type of said material, and the other is a vibration granulating machine 5 which loads a raw material moistened by stirring and blending action of the stirring blender in a container with a traverse arc crose-section 35, preliminarily granulating the raw material under the effect of a circular vibration given in a direction alonge the discharge direction of the raw material, further conducting the preliminarily granualated product to a container with a flat bottom 45 and giving a circular vibration in a direction along the discharge direction of said product, and finally rotating/ pelletizing the product to obtain mini-pellets.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a raw material granulating method and apparatus.

[0002]

2. Description of the Related Art FIG. 13 is a schematic view showing a conventional sintering process. In this conventional technique, a raw material charged in a fine ore tank 1 is cut out in a fixed amount by a lower constant feeder 2, which is conveyed by a belt conveyor 3, and a mini pellet is manufactured through a kneading machine 4 and a vibrating granulator 5. There is. On the other hand, after the normal sintering raw material quantitatively cut out by the lower constant feeder 7 of the mixing tank 6 is layered and mixed on the belt conveyor 8, the above-mentioned vibration-granulated mini-pellets and the above-mentioned normal sintering raw material are mixed. Are mixed in a drum mixer 9, and these are mixed from a belt chute 12 through a feed hopper 10 and a drum feeder 11 to a pallet 14 of a DL type sintering machine 13.
Charging into the ignition furnace 15, the coke in the raw material is ignited,
Sinter.

Here, the applicant of the present invention discloses, in Japanese Patent Application No. 1-269416, the construction of the above-mentioned kneader 4 and vibration granulator 5 as shown in FIG.
The following two are disclosed.

That is, the kneading machine 4 has a large number of rods (consolidation media) 41 housed in a drum 40, a vibrator 42 is attached to both sides of the drum 40, and these are placed on a spring 43. There is. The shaker 42 is attached to both sides of the drum 40 so as to be balanced and synchronized with each other so as to rotate synchronously, and cooperates with the spring 43 to impart circular vibration to the drum 40 and the consolidation medium 41.

Further, the vibrating granulator 5 is provided with a vibrating mechanism in which a vibrating machine 52 and a spring 53 are arranged around the drum 50, similar to the kneading machine 4, and circular vibration can be applied to the drum 50. It is a thing.

Therefore, in the prior art, when the sintering raw material is pre-granulated, the raw material is kneaded in the kneading machine 4 in the first step.
Water is added to obtain a proper granulation water content, and the consolidation medium 41 in the drum 42 exerts a comprehensive action on the material particles such as consolidation, shearing, rolling, crushing, kneading by kneading, etc. Squeezing and uniform spreading of surface water, and thus the compacted and plasticized flakes are supplied to the vibrating granulator 5 in the second step, which is tumbled and granulated by the circular vibration of the drum 50. Manufactured mini pellets.

[0007]

However, the prior art has the following problems.

As a first step for granulation, a vibrating kneader using a compaction medium is used. In the case of a large amount of processing, the weight of the vibrating body becomes large and the resulting inertial force becomes large. It is a problem to secure the durability of and the measures against the vibration of the stand.

As the second step for granulation, a vibrating granulator which vibrates a drum mounted on a spring by a vibrating machine is used, and the amplitude is 7 to 8 mm from the stable vibration region of the spring. The above cannot be obtained so much, and there is a limit in improving the granulation property and the processing capacity. That is, the yield of particles having a particle size of 2 to 10 mm is as low as 60% by weight or less.

Since the vibration-granulated mini-pellets and ordinary sintering raw materials are mixed in the drum mixer, the shearing force generated between the moving layer and the stationary layer of the raw materials in the mixer causes the mini-pellets to collapse. However, the residual rate is low. Therefore, when sintering the sintering raw material on the pallet, the air permeability is poor,
This leads to reduced productivity and excessive power consumption of the main exhaust fan.

It is an object of the present invention to improve the granulating property and the processing capacity without performing the consolidation plasticization kneading which requires the durability of the machine body and the measures against the vibration of the gantry during the granulation.

Another object of the present invention is to prevent the granulated mini-pellets from collapsing during handling during sintering.

[0013]

The present invention according to claim 1 comprises a first step of adding the amount of water necessary for granulating the raw material, which is determined according to the raw material, and stirring and mixing the raw material. The raw material moistened by stirring and mixing in the first step is charged into a lateral arcuate cross-section container, and subjected to circular vibration in a direction along the discharge direction of the raw material to carry out preliminary granulation, and further the preliminary granulated product. Is introduced into a flat bottom container, circular vibration is applied in a direction along the discharging direction of the raw material, and the raw material is tumbled and agglomerated to obtain mini pellets. .

The present invention according to claim 2 is the method according to claim 1, wherein the raw material is a sintering raw material supplied to a DL type sintering machine, and a raw material layer in a flat bottom container. With the thickness of 10 mm or less, a circular vibration with an amplitude of 10 to 30 mm in the direction along which the raw material is discharged is applied for 4 seconds or more.

According to a third aspect of the present invention, in the method of the present invention according to the second aspect, the raw material is only fine iron ore containing 60% by weight or more of particles having a particle size of less than 63 μm. It is a thing.

The present invention according to claim 4 provides the invention according to claims 1 to 3.
In the method of the present invention according to any one of the above, further the amount of water added is from the amount of water necessary to make the yield of particles having a particle size of 2 to 10 mm by granulation of the raw material determined according to the raw material 80% by weight. The water content of the raw material is deducted from the water content.

According to a fifth aspect of the present invention, the amount of water required for granulating the raw material, which is determined according to the raw material, is added, and the raw material is stirred and mixed by stirring and mixing with the stirring mixer. The moistened raw material is loaded into a horizontal arc-shaped cross-section container, preliminarily granulated by applying circular vibration in a direction along the discharge direction of the raw material, and then the preliminarily granulated product is introduced into a flat bottom container. And a vibrating granulator that imparts circular vibration in a direction along the discharge direction of the raw material and roll-agglomerates the raw material to obtain mini pellets.

According to a sixth aspect of the present invention, in the apparatus of the present invention according to the fifth aspect, the agitating mixer further comprises two spiral blade shafts rotating in opposite directions in a container. The container is provided with a raw material inlet on the spiral blade shaft starting end side, a raw material discharging port on the spiral blade shaft end side, and a humidifying device downstream of the raw material charging port. is there.

According to a seventh aspect of the present invention, in the apparatus of the present invention according to the fifth aspect, the vibrating granulator further has eccentricity corresponding to each of the horizontal arcuate cross-section container and the flat bottom container. It is configured to be supported by a shaft and to impart circular vibration due to rotation of an eccentric shaft corresponding to the raw material in each container.

The present invention according to claim 8 is defined by claims 1 to 4.
The mini-pets that have been vibrated and granulated by the granulation method of the raw material according to any one of 1 above, are directly sent without passing through a drum mixer,
This is a method of sintering raw materials to be charged into a pallet of a sintering machine.

[0021]

The principle of the present invention will be described with reference to the raw material water content and the binding state in a single particle due to vibration energy shown in FIG.

As shown in FIG. 2, it is known that when a fine powder raw material having a certain water content is stored in a container and vibration acceleration is applied in the direction of compressing the raw material, the density of the fine powder in the container increases. At this time, the filling state of the particles changes depending on the water content of the fine powder raw material in the container and the magnitude of the excitation energy, and the density increases according to the filling state. The graph of FIG. 2 shows this.

When the water content of the fine powder raw material is low, voids with air exist between the particles of the powder, and the powder is in a dry mixture. When the water content of the fine powder raw material is increased and vibrated, the water is uniformly and uniformly spread on the surface of the particles, voids in the air layer are eliminated, and the entire granules are in a sticky plasticized state, resulting in a dry density of the fine powder raw material. Approaches a curve with zero porosity.

When the water content further increases, the powder becomes a thick slurry. The plastic state in which the water content is less than that in the slurry state and the voids in the air layer are the smallest is called a capillary region, and the powder has the highest dry density and a high density flake state.

In order to obtain the powder in the capillary region, it is possible to obtain it by applying the vibration of the most appropriate water content and the appropriate energy according to the properties of the particles of the granules. The present invention is a method of granulating a raw material using this principle, in which in the first step, stirring and mixing are performed to add an appropriate amount of water to moisturize to an appropriate granulated water state, and A powder moistened with uniform water is obtained. Then, in a second step, circular moisture is applied to the powder that has been mixed with the proper granulation water and moistened with uniform water to cause the water in the particles to permeate to the surface. Adhesion and growth are caused, and rolling granulation is performed.

Next, the operation of using the lateral arcuate cross-section container and the flat bottom container in the second step of the present invention will be described using the flat bottom container with the arc surface shown in FIG. . That is, FIG. 9 shows that a raw material is charged into a flat bottom container having an arc surface, and a circular vibration having an amplitude of 15 mm and a frequency of 678 times / minute or more is counterclockwise in the direction along the longitudinal direction of the container. FIG. 3 schematically shows the granulation phenomenon occurring in the container when applied to the container.

Here, the container is arranged with a downward gradient of 10 degrees from the arc surface side toward the downstream side of the flat plate-shaped bottom surface, and the granulation area I on the arc surface side, and the upstream part of the flat plate-shaped bottom surface. The following granulation action is exhibited in each of the granulation region II, which is the above, and the granulation region III, which is the downstream portion of the flat bottom surface. The rotation direction of the circular vibration acting on the raw material in the container is that the upper half direction is toward the upstream side of the flat plate-shaped bottom surface, so the fine granules move to the upstream side and the granules at the upstream end It is inverted and stirred on the arc surface of zone I, and core particles are formed. On the other hand, the grown particles move to the downstream side due to gravity and are unevenly distributed in the granulation region III which is the downstream end.

(A) In the granulation region I, the ungranulated powder and the fine particles circulate integrally to form fine core particles.

(B) In the granulation zone II, the core particles are granulated, and the balls that have grown to a certain size or larger are recycled to the granulation zone III, and the fine particles are recycled to the granulation zone I. Therefore, here, in addition to granulation and growth of grains, a grain size regulating action is performed.

(C) In the granulation region III, the balls grown to have a grain size of 2 mm or more circulate in this region and are struck by the vibration of the container to improve the strength.

(D) In the flat bottoms of the granulation regions II and III, the raw material layer thickness is smaller than that of the cylindrical bottom, and the individual balls can freely fly and roll. Is good. Further, balls having a particle size of 2 mm or more are separated and do not recirculate to the granulation region I, so that the particle sizes are uniform and the particle size distribution is sharp as shown in FIG.

However, in the second step of the present invention, the above-mentioned granulation area I is constituted by the lateral arcuate cross-section container, and the above-mentioned granulation areas II, III are constituted by the flat bottom container. . That is, by constructing the granulation area I with a transverse arcuate cross-section container and making it into a transverse arcuate cross-section container such as a half cylinder, the circulation speed is increased and the granulation speed is improved. .. Then, the fine core particles formed in the horizontal arcuate cross-section container, which is the granulation area I, are loaded into the flat bottom container that is the granulation areas II and III, and circular vibration occurs in the direction along the discharge direction of the raw material. By this, it is possible to granulate mini pellets having a grain size of 2 to 10 mm and a yield of 80% by weight or more due to rolling agglomeration and grain adjusting action.

In the first step, the amount of water added to the raw material is based on the water content (appropriate granulation water) when the yield of mini-pellets having a particle size of 2 to 10 mm is 80% by weight or more. Is the deficit of water that is subtracted from the amount of water originally held by
It depends on the brand of raw material. As an example, Kudrem ore has a water content of 8.8% and an appropriate granulation water content of 10.6%, so the added water content is 1.8%. For MBR ore, the water content is 9.5% and the proper granulation water content is 11.5%, so the added water content is 2.0%.

Therefore, according to the present invention, the following effects (1) to (3) are obtained. The first step for granulation is to perform proper plasticization and kneading by a vibration-type kneader using a compaction medium, etc., and to perform proper water addition and uniform stirring and mixing, without causing vibration. Therefore, it is not necessary to secure the durability of the special machine body or take measures against the vibration of the frame.

The stirring and mixing machine used in the first step is 2
When the raw material is agitated and mixed by the rotation of the spiral blade shaft of the book, a uniform wet body can be obtained in a short staying time, and vibration is not generated.

The second step for granulation is, for example, a particle diameter of 2 mm by preliminary granulation by circular vibration of a transverse arcuate cross-section container.
Increase the granulation rate of the above, further reduce the raw material layer thickness of the flat bottom container to 10 mm or less, and improve the granulation property and processing capacity by circular vibration that increases the amplitude to 10 to 30 mm,
For example, using only fine iron ore containing 60% by weight or more of particles having a particle size of less than 63 μmm as a raw material, the yield of particles having a particle size of 2 to 10 mm can be increased to 80% by weight or more.

When the vibrating granulator used in the second step imparts circular vibration due to the rotation of the eccentric shaft to the raw materials in each of the lateral arcuate cross-section container and the flat bottom container, By adjusting the amount of eccentricity of the eccentric shaft, the amplitude can be more than doubled compared to the conventional one.

Since no excessive load is applied to each container of the vibrating granulator, the weight of the vibrating body can be reduced, and the vibration transmitted to the gantry can be reduced by providing the balance weight. And the vibration of the gantry can be prevented, which simplifies the equipment and improves the reliability of the machine.

Since the vibrating granulator is directly placed without passing through the drum mixer by placing the vibrating granulator in close proximity to the ore feeding section of the sintering machine or the like, it is charged into the pallet of the sintering machine. , It is possible to prevent the collapse of the mini pellet during handling. As a result, the remaining rate is high and the strength of the green ball can be secured at 100 to 120 g. Therefore, when the sintering raw material is sintered on the pallet, the air permeability is good, the productivity is improved, and the power consumption of the main air exhauster can be reduced.

As a result of improving the air permeability during sintering, a large amount of PF can be blended, and the raw material cost can be reduced.

[0041]

EXAMPLE FIG. 1 is a sintering process diagram showing an embodiment of the method of the present invention, FIG. 2 is a schematic diagram showing the bonding state between single particles due to the water content of raw materials and vibration energy, and FIG. FIG. 4 is a side sectional view showing an example of a vibrating granulator, FIG. 6 is a front view of FIG. 5, and FIG. 7 is a horizontal circle. FIG. 8 is a schematic view showing an arcuate cross-section container, FIG. 8 is a side view showing a multilayer vibrating granulator, FIG. 9 is a schematic view showing a granulation phenomenon by a flat bottom container having an arc surface, and FIG. Fig. 11 is a schematic diagram showing the particle size distribution of the product by a machine, Fig. 11 is a diagram showing the granulation results by the method of the present invention, Fig. 12 is a perspective view showing a conventional vibrating granulator, and Fig. 13 is a sintering process diagram of the conventional method. Is.

In the sintering process for the DL type sintering machine using the method of the present invention, as shown in FIG. 1, the fine powder raw material charged in the fine powder ore tank 1 is cut out in a fixed amount by the lower constant feeder 2 and Is conveyed by a belt conveyer 3 and this raw material is supplied to a stirring and mixing machine 4 to be mixed with proper granulation water and stirred and mixed so as to obtain a uniform water content. Further, this raw material is supplied to a vibrating granulator 5 to pre-granulate mini-pellets having a particle size of 2 to 10 mm and a yield of 80% by weight or more. On the other hand, ordinary sintering raw materials (returned ore, limestone, coke, powder ore, etc.) quantitatively cut by the lower constant feeder 7 of the compounding tank 6 are stacked and compounded on the belt conveyor 8 and then mixed in a drum mixer. At 9, the water is added so that the water content of the entire raw material becomes 5 to 7%, mixed by the rotation of the drum, tumbled and granulated, conveyed to the ore hopper 10, and cut out quantitatively by the drum feeder 11. Then, the vibration-granulated mini-pellets and the secondary compounding raw materials are mixed on the belt chute 12, and D
After charging to the pallet 14 of the L-type sintering machine 13, the ignition furnace 1
At 5, the coke in the raw material is ignited and sintered.

Here, the stirring and mixing machine 4 is as shown in FIGS. That is, the agitation mixer 4 has two twin U-shaped containers 18 fixed to a pedestal 17 via a pedestal 16 and two spiral blade shafts 19, which rotate in mutually opposite directions (the upper half is rotated outward). 20 are arranged side by side, and stirring blades 21 are spirally fixed to the spiral blade shafts 19 and 20. The respective spiral blade shafts 19 and 20 are supported by bearings 22 on both side shaft ends, and a drive motor 24 is connected to the shaft ends on the mining side via a shaft joint 23. Further, a raw material inlet 25 is provided on the start side of the spiral blade shafts 19 and 20 of the twin U-shaped container 18, and a raw material discharge port 26 is provided on the end side of the spiral blade shafts 19 and 20.
A humidifier 27 is provided downstream of the raw material charging port 25.

The vibrating granulator 5 is as shown in FIGS. That is, the vibrating granulator 5 is mounted on the pedestal 30.
Two eccentric shafts 33, 34 are rotatably supported via bearings 31, 32, and the eccentric shafts 33, 34 support a half-cylindrical lateral arcuate cross-section container 35. Incidentally, 36 is a main bracket, 37 is a sub bracket, and 38 is a connecting pin.

Further, the vibrating granulator 5 supports two eccentric shafts 43 and 44 on the pedestal 30 via bearings 41 and 42, and these eccentric shafts 43 and 44 form a wide-angle trough shape. The flat bottom container 45 is supported. Incidentally, 46 is a main bracket, 47 is a sub bracket, and 48 is a connecting pin.

The eccentric shafts 33 and 43 are connected to the shaft coupling 4
9, driven by a drive motor 52 connected via an intermediate shaft 51, and the eccentric shafts 43, 44 are connected to the timing belt 5
It is driven synchronously with the eccentric shafts 33, 43 via 3, 54. As a result, the vibrating granulator 5 operates in the respective containers 35, 45.
Circular vibration (amplitude 10 to 30 mm, frequency 600 to 1000 times / frequency) of vibration acceleration 3G to 10G by the eccentric shafts 33, 34, 43, 44 in the direction along the discharge direction of the material concerned.
Minutes).

At this time, as shown in FIG. 7, the lateral arcuate cross-section container 35 has an upper surface connecting the front edge part and the rear edge part of the arcuate cross-section as a forward downward slope surface. A raw material restraint plate 35A is erected in the central portion in the width direction, a rear region of the raw material restraint plate 35A is used as a raw material charging portion 35B, and both side regions of the raw material restraint plate 35A are used as raw material discharge portions 35C to the flat bottom container 45. . And the lateral arcuate cross-section container 3
5 is fed with a raw material from the raw material feeding portion 35B under the condition that the above-mentioned eccentric shafts 33 and 34 are circularly oscillated in the clockwise direction in FIG.
In the rear area of A, let it slip into the container 35 as well.
The inner bottom portion is distributed to the left and right, and the container 35 is made to flow along the arc surface of the container 35 so as to be wound around the trailing edge portion, and then overflowed from the raw material discharge portion 35C. As a result, the raw material in the lateral arcuate section container 35 is agitated and pre-granulated.

The flat bottom container 45 is supported substantially horizontally within the pair of left and right main brackets 46, and the eccentric shaft 4 described above is used.
5, the raw material is fed from the raw material feeding portion 45A on the side of the lateral arc-shaped cross-section container 35, and the raw material is fed to the raw material discharging portion 45B. Can be sent to. Here, the raw material in the container 45 is set to have a layer thickness of 10 mm or less. As a result, the raw material in the container 45 is subjected to circular vibration with an amplitude of 10 to 30 mm for 4 seconds or more, rolling-agglomerated, and becomes mini-pellets.

The flat bottom container 45 is the same as that shown in FIG.
As in the flat bottom container of FIG. 5, a downward slope of, for example, 10 degrees is applied from the raw material charging section 45A to the raw material discharging section 45B, and counterclockwise circular vibration in FIG. 5 is applied. May be. According to this, the container 45
In the inside, the fine particles move to the raw material charging section 45A side and are agitated to become core particles, while the grown particles move to the raw material discharging section 45B side by gravity and are discharged in a state where the particle size is made uniform. Become.

The multi-layer vibrating granulator shown in FIG. 8 is obtained by stacking the vibrating granulators 5 shown in FIGS. 5 and 6. Since each of the vibrating granulators 5 has a relatively flat shape, the space efficiency of the equipment can be improved due to the multilayer structure.

Next, the granulation results of the sintering raw material supplied to the DL type sintering machine according to the present invention, particularly the raw material only of fine iron ore containing 60% by weight or more of particles having a particle size of less than 63 μm will be described.

In FIG. 11 (A), circular flat vibration having an amplitude of 16 mm and a frequency of 900 times / minute is applied to the flat bottom container 45 of the vibrating granulator 5, and the trough length is variously changed to keep the staying time. Seeking,
The relationship between the retention time and the yield of green balls with a particle size of 2 to 10 mm in the granulated product is shown. From this, it is recognized that a retention time of 4 seconds or more is required to obtain a yield of 80% by weight or more for particles having a particle size of 2 to 10 mm.

Further, FIG. 11B shows that the flat bottom container 45 of the vibrating granulator 5 was subjected to a circular vibration with a vibration frequency of 900 times / min and a retention time of 5 seconds, and the amplitude was changed variously. The relationship between the amplitude and the yield of green balls with a particle size of 2 to 10 mm in the granulated product is shown. From this, the larger the amplitude, the better the yield of particles with a particle size of 2-10 mm, but
To obtain a yield of 80% by weight of 0 mm, an amplitude of 10-30 m
m, preferably 15 mm or more is considered appropriate.

Further, as shown in FIG. 11 (C), the flat bottom container 45 of the vibrating granulator 5 was subjected to a circular vibration with an amplitude of 16 mm, a vibration frequency of 900 times / minute, and a retention time of 5 seconds, so that the amount of raw material charged was changed. It shows the relationship between the raw material layer thickness and the yield of green balls with a particle size of 2 to 10 mm in the granulated product when variously changed. The thinner the raw material layer, the better, but 10 mm or less is considered appropriate.

According to the above embodiment, the following effects (1) to (3) are obtained. The first step for granulation is to perform proper plasticization and kneading by a vibration-type kneader using a compaction medium, etc., and to perform proper water addition and uniform stirring and mixing, without causing vibration. Therefore, it is not necessary to secure the durability of the special machine body or take measures against the vibration of the frame.

The stirring and mixing machine 4 used in the first step is
When the raw materials are agitated and mixed by the rotation of the two spiral blade shafts 19 and 20, a uniform wet body can be obtained in a short staying time and no vibration is generated.

The second step for granulation is, for example, a particle size by preliminary granulation by circular vibration of the lateral arcuate cross-section container 35.
Increased granulation rate of 2 mm or more, and further flat bottom container 4
The raw material layer of No. 5 is thinned to 10 mm or less, and the amplitude is 10 to 30 mm.
Granularity and processing capacity are improved by increasing circular vibration as shown in the example below.For example, using only fine iron ore containing 60 wt% or more of particles with a particle size of 63 μmm or more as a raw material, the yield of particles with a particle size of 2 to 10 mm can be obtained. It can be as high as 80% by weight or more.

The vibration granulator 5 used in the second step is
When the circular vibration due to the rotation of the eccentric shafts 33, 34, 43, 44 is applied to the raw materials in each of the lateral arcuate cross-section container 35 and the flat bottom container 45, the eccentric shafts 33, 34,
By adjusting the eccentricity of 43 and 44, the amplitude can be doubled or more than that of the conventional one.

Further, since an excessive load does not act on each container 35, 45 of the vibrating granulator 5, the weight of the vibrating body can be reduced,
Moreover, since the vibration transmitted to the gantry 30 can be reduced by providing the balance weight, the durability of the machine can be improved and the vibration of the gantry 30 can be prevented, and the equipment can be simplified and the reliability of the machine can be improved.

By placing the vibrating granulator 5 close to the ore feeding section of the sintering machine 13, etc.
Since it is directly sent without passing through the drum mixer and is loaded into the pallet 14 of the sintering machine 13, it is possible to prevent collapse of the mini pellets in handling. As a result, the remaining rate is high and the strength of the green ball can be secured at 100 to 120 g.
Therefore, when the sintering raw material is sintered on the pallet 14, the air permeability is good, the productivity is improved, and the power consumption of the main air exhauster can be reduced.

As a result of improving the air permeability during sintering, a large amount of PF can be blended, and the raw material cost can be reduced.

The results of the method of the present invention are shown in Table 1 as compared with the conventional method. Here, the production rate of the sintering machine is (a) grain size
By improving the yield by 2-10 mm, the air permeability is good and the sintering time can be shortened. (B) By improving the crushing strength, there is little disintegration, the air permeability can be secured, and the sintering time can be shortened to 1.7 (ton / ton / It is thought that the time has been improved to m ² ).

[0063]

[Table 1]

[0064]

As described above, according to the present invention, during granulation, the compaction plasticizing and kneading, which requires the durability of the machine body and the measures against the vibration of the gantry, is not performed, and the granulation property and the processing capacity are improved. Can be improved.

Further, according to the present invention, it is possible to prevent the granulated mini-pellets from collapsing during handling during sintering.

[Brief description of drawings]

FIG. 1 is a sintering process diagram showing an embodiment of the method of the present invention.

FIG. 2 is a schematic diagram showing a bonding state between single particles due to a water content of a raw material and vibration energy.

FIG. 3 is a side sectional view showing an example of a stirring mixer.

FIG. 4 is a sectional view taken along line IV-IV in FIG.

FIG. 5 is a side view showing an example of a vibrating granulator.

FIG. 6 is a front view of FIG.

FIG. 7 is a schematic view showing a lateral arcuate cross-section container.

FIG. 8 is a side view showing a multilayer vibrating granulator.

FIG. 9 is a schematic diagram showing a granulation phenomenon by a flat bottom container having an arc surface.

FIG. 10 is a schematic diagram showing a particle size distribution of a product produced by the granulator of FIG. 9.

FIG. 11 is a diagram showing granulation results by the method of the present invention.

FIG. 12 is a perspective view showing a conventional vibrating granulator.

FIG. 13 is a sintering process diagram of a conventional method.

[Explanation of symbols]

4 stirring mixer 5 Vibration granulator 13 Sintering machine 18 containers 19, 20 spiral blade shaft 25 Raw material inlet 26 Raw material outlet 27 Humidifier 33, 34 Eccentric shaft 35 Horizontal arc-shaped container 43,44 Eccentric shaft 45 Flat bottom container

Claims (8)

[Claims] 1. A first step of adding a necessary amount of water for granulation of the raw material, which is determined according to the raw material, and stirring and mixing the raw material, and a raw material moistened by the stirring and mixing in the first step. Preliminarily granulate by charging in a horizontal arc-shaped cross-section container and applying circular vibration in a direction along the discharge direction of the raw material, and further introducing the preliminary granulated product into a flat bottom container, the discharge direction of the raw material A second step of imparting circular vibration in a direction along the line to tumbl agglomerate the raw material to obtain mini-pellets. 2. The raw material is a sintering raw material supplied to a DL type sintering machine, and the amplitude of the raw material layer in the flat bottom container is 10 mm or less in the direction along the discharge direction of the raw material. The method for granulating a raw material according to claim 1, wherein a circular vibration of -30 mm is applied for 4 seconds or more. 3. The method for granulating a raw material according to claim 2, wherein the raw material is only fine iron ore containing 60% by weight or more of particles having a particle size of less than 63 μm. 4. The amount of water added is determined from the amount of water required to bring the yield of 80% by weight of the particles having a particle size of 2 to 10 mm obtained by granulating the raw material, which is determined depending on the raw material. 4. The method of granulating a raw material according to claim 1, wherein the water content is the amount of water deficit less than. 5. A horizontal circle of a stir mixer for adding the amount of water necessary for granulating the raw material, which is determined according to the raw material, and stirring and mixing the raw material, and a raw material moistened by stirring and mixing by the stir mixer. It is charged into an arcuate cross-section container and subjected to circular vibration in a direction along the discharge direction of the raw material to pre-granulate, and further the pre-granulated product is introduced into a flat bottom container, along the discharge direction of the raw material. Granulating apparatus for raw material, which is configured to include a vibration granulator that imparts circular vibration in a direction to rolling agglomerate the raw material to obtain mini pellets. 6. The agitator / mixer comprises two spiral blade shafts that rotate in mutually opposite directions side by side in a container, a raw material inlet is provided on the spiral blade shaft starting end side of the container, and the spiral blade shaft end is formed. The raw material granulating apparatus according to claim 5, wherein the raw material discharging port is provided on the side, and the humidifying device is provided on the downstream side of the raw material charging port. 7. The vibrating granulator supports each container of a lateral arcuate cross-section container and a flat plate bottom container by a corresponding eccentric shaft, and circular vibration by rotation of an eccentric shaft corresponding to a raw material in each container. The apparatus for granulating a raw material according to claim 5, wherein the granulating apparatus is a raw material granulating apparatus. 8. A mini-pet vibrated and granulated by the method for granulating a raw material according to any one of claims 1 to 4, which is directly fed without passing through a drum mixer and charged into a pallet of a sintering machine. Sintering method.