JPH0148816B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION BACKGROUND OF THE INVENTION (Field of Industrial Application) The present invention relates to a granulation device that solidifies powder to produce granules. (Prior Art) It has been common practice to solidify powder and shape it into granules. For example, iron ore pellets. This is to improve the quality of poor ore.
The ore is first crushed, then beneficent, and then solidified into easy-to-handle granules. In addition, recently it has been considered to transport lignite after pulverizing and beneficiation, but there is a risk of spontaneous combustion or powder explosion if the lignite is transported as a powder, so it is preferable to transport the lignite in the form of granules. It will be done. Furthermore, as a familiar product, there are tablets made by hardening powdered medicine to make it easier to swallow. These granulated products are desirably compacted in order to achieve the shape and strength most suited to the conditions and purpose of each use and to eliminate bulk. However, conventional granulation equipment uses a disk that rotates around a vertical axis to apply centrifugal force and rotation to the powder, causing it to move up and down a fixed peripheral wall around the disk, creating a spiral circulation flow. Then, the surrounding powder adheres to the cores created by self-granulation in a snowball-like manner and grows into large granules. For this reason, the granulated granules simply swell while adhering to the powder, resulting in a disadvantage that their density becomes coarse and they are easily crushed. Even if granular materials are baked and hardened, only the surface becomes strong, but the inside is not compacted and remains soft and easily crushed. OBJECT OF THE INVENTION An object of the present invention is to provide a granulation device capable of granulating dense granules. Structure of the Invention (Characteristic Structure of the Invention) To achieve the above object, the present invention rotates a disc of a granulating device while vibrating it in the vertical direction, and granules in the middle of granulation are caused to fall in a circle due to gravity. By rotating the powder in a spiral manner while colliding with the plate, it is made to advance in the circumferential direction, thereby solidifying the adhered powder and growing the grains. (Specific Structure of the Invention) FIG. 1 is a partially cutaway front view of an embodiment of the granulation device of the present invention, FIG. 2 is an enlarged longitudinal cross-sectional view of a disc portion, and FIG. 3 is a container FIG. 2 is a diagram showing the outlet and shutter portion of the apparatus, in which a is a cross-sectional plan view and b is a front view thereof. In FIG. 1, the granulation device includes a drum-shaped container 1, a disc 2 forming the bottom of the container 1, and a rotation drive system 3 that rotates the disc 2 in an undulating manner.
It mainly consists of a drive source 4 for these and a pedestal 17 that supports them. As is clear from FIGS. 1 and 2, the disc 2 is supported by a shaft 5 at the bottom of the container 1,
A shaft 6 is arranged concentrically with this shaft 5, and both shafts 5 and 6 are supported by spherical bearings 7 and 8, respectively. That is, the disc 2 is tiltably attached via a spherical bearing 7 to an inner rotating shaft 5 penetrating inside the boss portion 2a of the disc 2, and has a notch open in the axial direction. 9
A connecting pin 10 passing through the rotating shaft 5 is fitted into the shaft 5 so that it is engaged only in the circumferential direction and can freely move in the vertical direction. On the other hand, the lower end portion of the boss portion 2a of the disc 2 is supported by a spherical bearing 8 fixed to the upper end of the outer swinging shaft 6, and is rotatable and tiltable with respect to the swinging shaft 6. Supported. Here, it is slidably mounted on the housing 11 of the spherical bearing 8 on a pedestal 13 at the upper end of the swinging shaft 6, and can be eccentric to the swinging shaft 6 using a plurality of fine adjustment screws 12. is fixed. Therefore, the inclination angle θ of the disc 2 can be changed by moving the housing 11 of the spherical bearing 8 by operating the fine adjustment screw 12. In addition, the disk 2 has countless fine grooves 1 on its surface.
It has 4. The grooves 14 increase the coefficient of friction of the disc 2 to enhance the granulation effect, and are formed in a line pattern such as a radial pattern, a heptad pattern, or a fish scale pattern. If the grooves 14 do not exist, the core granules during the granulation process do not roll on the disk 2 but rotate around a substantially vertical axis, so they are likely to be granulated into flat granules. The rotating shaft 5 and the swinging shaft 6 that support the disk 2 described above are rotated by a large diameter pulley P ₁ and a small diameter pulley P ₂ provided at their lower ends.
Belts V ₁ and V ₂ are wound around these pulleys P ₁ and P ₂ , and these belts V ₁ and V ₂ are connected to continuously variable transmissions 15 and 1.
It is connected to a motor, which is a driving source 4, via 6. Therefore, the rotation of the disk 2 can be driven at any rotational speed, but if the rotation is low, not only will the rate of turning the powder raw material into particles is low, but the particle size will not become large, and the If the rotation is low, even if it becomes a ball, it will quickly collapse, so it is preferable to use a relatively high speed. On the other hand, in order to swing the disc 2, the rotation of the housing 11 needs to be different from the rotation speed of the disc 2; In order to prevent vibrations, it is preferable to keep the rotational speed within a range that does not significantly differ from the rotational speed of the disk 2. For example, in this embodiment, the rotation of the disk 2 is
Continuously variable transmission 15 that changes speed in the range of 100 to 300 rpm
and a continuously variable transmission 16 that changes the rotation speed of the housing 11 in a range of 600 to 150 rpm. In this embodiment, the drive source 4 is shared, but each shaft 5, 6 may be provided with its own drive source. The swinging shaft 6 is rotatably supported by a bearing 18 on a pedestal 17, and the rotating shaft 5 is inserted into the oscillation shaft 6, and is supported by a bearing 19 and a thrust bearing 20 on the pedestal 17.
It is rotatably supported. Incidentally, in the case of this embodiment, the rotary drive system 3 that transmits the rotation of the drive source 4 to these shafts 5 and 6 has a V
Although a belt transmission mechanism is employed, other transmission means may be employed, such as a chain sprocket. The disk 2 constitutes the bottom of the drum-shaped container 1 and defines a granulation chamber 21 between it and the top of the container 1. A slight gap S is provided between the disc 2 and the drum-shaped container 1. This time S
This allows the movement of the disc 2 which rotates while vibrating in a undulating manner, and also allows the jetting of compressed air from the peripheral edge of the disc 2. Air injection is applied to the container peripheral wall 1a in the granulation chamber 21.
The powder that has been blown to the side is suspended inward by being suspended, helping to make the powder spheroidal. This air injection supplies compressed air to a pressure chamber 22 defined between the lower part of the container 1 and the disc 2 (not shown).
This is carried out by introducing the liquid from the periphery of the disk 2 and blowing it out from the entire peripheral edge of the disk 2, that is, the space S between the container 1 and the disk 2. The pressure chamber 22 is isolated from the swinging shaft 6 that supports the disc 2, the spherical bearing 8, etc., and a cylindrical dust cover 23, so that dust brought in from the outside by compressed air can enter the shaft side. In addition, it is designed to mutually prevent oil and the like splashed from the bearings 7, 8, and 19 from being carried away by the injection air. The container 1 is placed and fixed on a pedestal 17. This container 1 can be opened and closed by covering its upper opening with a removable lid 24, and the raw material powder is introduced from above. Note that the lid 24 is provided with an exhaust port 31 for discharging the air inside the granulation chamber 21 . Further, the inner circumferential wall surface of the container 1 is provided with a step formed by a curved surface, and a return 25 is formed that guides the air ejected along the circumferential wall inward and turns it into a vortex. Furthermore, an outlet 26 is provided on the peripheral wall of the container 1 to take out the granulated material. As shown in FIG. 3, this outlet 26 is provided so that it can be opened and closed from above by means of a shutter 27 that moves up and down along the outer wall of the container 1, and can be opened and closed as needed, or its opening/closing amount can be controlled. Can be adjusted. Therefore, continuous operation is possible, and by controlling the amount of opening and closing of the take-out port 26, it is also possible to take out only grains of a desired size or less, making it possible to sort them. Of course, when carrying out batch operation,
The outlet 26 is not necessary and may be kept closed. A trough 28 is connected to the shutter 27, and the trough 28 moves up and down in conjunction with the shutter 27, and is connected to the open outlet 26. Moreover, this shutter 27 is
As shown in Figure b, it has two vertically long grooves 29,
Two tightening screws 30 screwed into the container 1 are passed through the long grooves 29, so that the container 1 can be moved vertically. Next, the action will be explained. The raw material powder introduced into the granulation chamber 21 is, for example,
The initial moisture content (volume percentage) is about 15%. First, this raw material powder is put into the granulation chamber 21, and the disk 2 is rotated. Due to the rotation of this disc 2, it is gathered at the corner part 32 formed between the disc 2, the container 1, and the peripheral wall surface 1a, and due to the friction between the fixed inner peripheral wall surface 1a of the container 1. This causes a spiral circulation flow and starts self-granulation. At this time, the powder is suspended by the air blown from the periphery of the disk 2 along the inner circumferential wall surface 1a of the container 1, forming a vortex that is drawn toward the center of rotation, thereby aiding self-granulation. The granules are placed in a container 1 on a rotating disk 2.
While rolling in contact with the inner wall surface 1a of the container 1, it adheres to surrounding powder and grows, but if the particle size is to be increased, moisture can be supplied from the top of the container 1 through a nozzle or the like. . This rehydration results in a considerably high final moisture content. In particular, in this embodiment, the rotation of the disc 2 is caused by the drive source 4, the belts V ₁ , V ₂ and the continuously variable transmissions 15 , 1
6 to pulleys P ₁ and P ₂ . Therefore, the disk 2 has a large diameter pulley P ₁
The housing 11 is rotated via the shaft 6 by a small diameter pulley _P2 . In this case, the housing 11
is displaced by the fine adjustment screw 12, so
This housing 11 will rotate at a position offset from the center of the shaft 5. Therefore, while being rotated by the shaft 5, the boss portion 2a of the disc 2 is regulated by the housing 11 and the bearing 8, and does not rotate in the same plane, but rotates while vibrating like a wave. Therefore, the granules bounce up and down and repeatedly collide with the disc 2, that is, collide with the disc 2 using gravity, and at this time, they grow while adhering the surrounding powder to the outer peripheral surface. I will do it. For this reason, the granules become hard and strong, evenly compacted to the core. The granules having a desired particle size sequentially overflow into the trough 28 from the outlet 26 of the container peripheral wall 1a. Then, it is transported to a predetermined container or location.
In addition, since the particle size of the granular material is determined by the rotation speed of the disk 2, the amount of powder, etc., the amount of powder input, the rotation speed of the disk, etc. are selected in accordance with the desired particle size. It is preferable to do so. According to experiments, if the water content of the raw material powder is, for example, about 3 to 5% by volume, the raw material powder will float and be suspended, and even if it is granulated, it will be extremely small. However, if the moisture content of the granules is around 15% as mentioned above, a relatively practical level can be obtained, and if the moisture content is increased by sprinkling water using the aforementioned nozzle etc. , it has been found that larger flow diameter granules can be obtained. [Example] A case will be described in which iron ore powder having a particle size of about 1 to 4 μm and alumina cement powder having a particle size of about 1 to 5 μm are used as raw material powders. First, a wet powder with a moisture content (volume percentage) of 15% is made with respect to 0.8 kg of the raw material powder in a mixer,
Load this into the granulator. The operating conditions of this granulator are air supply amount 700/
min, the rotation speed of the disc was 300 rpm, and the rotation speed of the housing 11 was 425 rpm, and the two-fluid nozzle sprayed water in the form of mist onto the wet powder being granulated. As a result, the particle size and distribution of each particle size of the granules regarding iron ore powder and alumina cement powder were as follows.

【table】

[Table] Effects of the Invention As is clear from the above explanation, according to the granulation device of the present invention, the disk for rotating the raw material powder is rotated while vibrating in the vertical direction, and the particles in the middle of granulation are moved by gravity. By colliding with the disc as it falls and moving it in the circumferential direction while rotating in a spiral pattern, the particles are repeatedly struck and the surrounding powder adheres to them, causing them to grow, resulting in uniform tightening down to the core. It is possible to granulate hard and strong granules.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway front view showing an embodiment of the granulation device according to the present invention, Fig. 2 is an enlarged vertical cross-sectional view of the disk portion, and Fig. 3 is the outlet and shutter portion of the container. In the figure, a is a cross-sectional plan view, and b is a front view thereof. 1...Container, 2...Disk, 2a...Boss part, 4
... Drive source, 5 ... Rotation shaft, 6 ... Rocking shaft, 7, 8 ... Spherical bearing, 10 ... Connection pin, 11 ... Housing, 12 ... Fine adjustment screw.

Claims (1)

[Claims] 1. A granulating device in which a disk is provided at the bottom of a drum container, and the rotation of the disk causes the powder raw material to flow in a spiral manner between the peripheral wall surface of the drum container and granulate. A granulation device characterized by rotating a plate while vibrating it in the vertical direction, causing particles in the middle of granulation to collide with the disk due to gravity fall and advance in the circumferential direction while rotating in a spiral shape.