JPH0679675B2 - Operation method of centrifugal fluidized pulverizer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a crusher. More specifically, the present invention relates to a centrifugal fluidizing and pulverizing apparatus which is provided with an outer peripheral ring and a rotary dish, and which pulverizes raw materials by centrifugally flowing a pulverizing medium having an irregular shape housed inside the apparatus.

[Prior Art] There are various types of crushing devices such as a tube mill and a vertical mill, but the steel balls or ceramics housed inside are installed by installing the rotary plate upward and rotating the rotary plate. Grinding media such as balls (hereinafter referred to as balls)
What is commonly called a vertical ball mill is known in which the raw material is crushed and ground by circulating the material.

In this type of vertical ball mill that has been used for a long time, there is a problem that the crushing and grinding action is weak, or the energy input to the device is easily consumed other than the crushing and grinding action, and the energy efficiency is low. there were.

Therefore, the present applicant has applied for a patent for a centrifugal fluidizing and pulverizing apparatus having a rotating dish and a fixed ring as follows. (Japanese Patent Application Sho 60-2
65379,60-266867 to 266872,61-99745 etc.).

This rotating dish has a rotation axis oriented in the vertical direction, at least a central portion of which has a dish surface whose diameter expands downward, and a vertical cross section of the dish surface is concavely curved. It is like a dish.

The stationary ring has an inner wall surface with at least an upper portion having a diameter reduced upward, and has a shape in which a vertical cross section of the inner wall surface is curved in a concave shape. ing.

Further, in the centrifugal fluidizer, the plate surface of the rotary plate and the inner wall surface of the fixed ring are formed into a continuous smooth surface except for a minute gap between the rotary plate and the fixed ring.

[Problems to be Solved by the Invention] However, some pulverized raw materials have physical properties with particularly remarkable adhesiveness, and even if these are pulverized by a pulverizer, they adhere to the inner surface of the pulverization or the pulverization wall surface. Since the coating layer is formed, there is a disadvantage that it cannot be discharged to the outside of the crushing device, and even if it is separated from the crushing inner surface or crushing wall surface by some method, it cannot be reduced to a certain size or less. It was very difficult to obtain a fine powder.

[Means for Solving the Problems] In the operating method of the present invention, the rotation axis is oriented in the vertical direction, and at least the central portion has a dish surface that expands downward, and A rotatable circular rotating plate having a concave curved vertical section, and at least an upper portion having an inner wall surface whose diameter decreases upward, and the inner wall surface has a concave vertical section. A stationary ring that is in the shape of a ring and is coaxially provided around the rotary plate and is stationary, and the plate surface of the rotary plate and the inner wall surface of the fixed ring are between the rotary plate and the fixed ring. In the method of operating a centrifugal fluidized pulverizer having a continuous smooth surface except for minute gaps, an operation method of mixing a pulverizing medium having a non-spherical irregular shape as the pulverizing medium was adopted.

Then, the grinding medium having an irregular shape is any one of a cube, a rectangular parallelepiped, a cylinder, and a polygonal pyramid.

[Operation] In the operation method of the centrifugal fluidizing and crushing device of the present invention, a medium of a spherical ball made of steel or ceramics is mixed with a medium of irregular shape, for example, a pulverizing medium such as a cube, a rectangular parallelepiped, a cylinder or a polygonal pyramid. Since it is pulverized, even if the pulverized raw material is one that has extremely adherent physical properties and the pulverized fine powder adheres to the pulverizing surface or inner wall surface, it is mixed in the pulverizing medium and has an irregular shape. Edge of media (edge)
Contacting and sliding on these parts exerts a peeling action, thus preventing the growth and development of adhesion. Therefore, effective pulverization can be continued to obtain the required fine powder.

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

FIG. 1 is an overall side view of the centrifugal fluidizing and pulverizing apparatus, and FIG. 2 is a longitudinal sectional view of an essential part. FIG. 3 is a schematic perspective view of various irregular-shaped grinding media, FIG. 4 is a relational diagram showing a change with time of the grinding amount,
FIG. 5 is a relationship diagram between the mixing ratio of the odd-shaped medium and the crushing ability.

In the figure, reference numeral 1 is a fixed ring, and 2 is a rotating dish. The fixed ring 1 is fixed to the upper side of a drum-shaped casing 4 whose bottom surface is sealed by a plate 3, and the plate 3 is supported by a pedestal 5. A support block 6 is fixedly mounted on the rotary plate 2, and the support block 6 is supported by the plate 3 via a bearing device 7. That is, an opening 8 is formed in the central portion of the plate 3, the flange portion 10 of the bearing housing 9 is locked to the edge portion of the opening 8, and the bolt 8
It is fixed by 11. A drive shaft 12 is connected to the lower side of the support block 6, and the drive shaft 12 is connected to an output shaft 15 of a speed reducer 14 via a joint 13. Reference numeral 17 is a variable speed motor for driving, and is connected to the speed reducer 14.

A lid member 18 is attached to the upper side of the rotary plate 2. The lid member 18 is provided with a flange 19 on the outer periphery of the lower end thereof, and the flange 19 is mounted on a flange 20 projecting from the outer peripheral edge of the upper end of the fixed ring 1 and fixed by a bolt 21. A discharge pipe 22 is installed in the center of the lid member 18, and a chamber for crushing or reforming surrounded by the stationary ring 1, the rotary plate 2 and the lid member 18 inside the discharge pipe 22 (hereinafter referred to as a crushing chamber). It communicates with 23. The lid member 18 is provided with a charging pipe 24, and the inside of the charging pipe 24 communicates with the crushing chamber 23.

Next, the configurations of the fixed ring 1 and the rotary plate 2 will be described in detail with reference to FIG.

The fixed ring 1 has a ring shape installed with the axial direction being the vertical direction, and the diameter in the middle of the height direction (hereinafter referred to as the middle part) 1b is the largest. In the fixed ring 1, a lower portion (hereinafter, referred to as a lower portion) 1c is slightly reduced in diameter from the middle portion 1b, and an upper portion (hereinafter, referred to as an upper portion) 1a is reduced in diameter from the middle portion. is doing. Therefore,
The inner wall surface 1A of the fixed ring 1 is slightly expanded in diameter from the lower portion 1c toward the middle portion 1b, the middle portion 1b is substantially vertical, and the middle portion 1b is located at the upper portion.
The diameter is reduced toward 1a, and the inner wall surface 1A is curved in a vertical cross section. A flange 25 is provided on the outer peripheral surface of the middle portion 1b of the fixed ring 1, and the flange 25 is mounted on a flange 26 provided on the outer periphery of the upper end of the casing 3 and fixed by a bolt 27.

The plate surface 2A of the rotary plate 2 has a shape in which the diameter increases downward in the central portion 2a, it is substantially horizontal in the intermediate portion 2b that follows the central portion, and the outer peripheral portion 2c that follows the intermediate portion 2b.
Then, the diameter is increased upward. The dish surface 2A is curved in a concave shape as a whole, and the inner wall surface of the fixed ring 1 is formed.
1A and the dish surface 2A form a continuous smooth surface except for a minute gap 29 between the fixed ring 1 and the rotary dish 2.

A pointed cap 30 is attached to the central portion of the rotary plate 2,
It is fixed by bolts 31. A shaft hole 32 is formed in the central portion of the rotary plate 2, and the upper end of the support block 6 is fitted in the shaft hole 32. The lower end of the bolt 31 is screwed into a piece 33 provided on the upper end of the support block 6.

Although not shown, the inner wall surface 1A of the fixed ring 1 and the rotary plate 2
A liner is attached to each of the dish surfaces 2A.

An inlet 34 for introducing a gas such as air is formed in the plate 3 so that the gas can be introduced into a gas chamber 36 in the casing 4 through a pipe 35.

A powder collecting means (not shown) such as a back filter is connected to the discharge pipe 22.

Next, the pulverization process of the pulverization raw material made of the adhesive substance by the centrifugal fluidization pulverization device configured as described above will be described.

In the crushing chamber 23, for example, a crushing medium composed of, for example, spherical balls is mixed with a crushing medium having an irregular shape, for example, a cube, and charged. First, the pulverized raw material is charged into the apparatus through the charging pipe 24. A combination of a circular motion (arrow S) in which the crushing raw material and the crushing medium circulate between the inner wall surface 1A of the fixed ring 1 and the plate surface 2A with the rotation of the rotary plate 2 and an orbital motion of the rotary plate 2 around its axis. Performs a spiral movement (centrifugal flow) that twists the rope due to, while grinding or stripping the pulverized raw material.

That is, when the rotating dish 2 is rotated, the grinding medium is moved in the outer peripheral direction by the centrifugal force, and the velocity energy crawls up the inner wall surface 1A of the fixed ring 1, and when the climbing force becomes smaller than gravity, then It separates from the wall surface 1A and falls onto the plate surface 2A of the rotary plate 2. The grinding medium that has moved onto the dish surface 2A is again moved toward the fixed ring 1 along the dish surface 2A.

When the rotating dish 2 is rotated, the grinding medium revolves in the circumferential direction at a speed lower than the rotation speed of the rotating dish 2. Therefore, the crushing medium performs not only the circular motion S in the up-and-down direction which circulates the plate surface 2A and the inner wall surface 1A as described above, but also the revolution motion which rotates around the axis of the rotary plate 2. Performs a spiral movement (centrifugal flow) that twists the rope that synthesizes the movement.

In this way, the crushing medium makes a motion of climbing up the inner wall surface 1A while maintaining the movement of the rotary plate 2 in the circumferential direction. When the inner wall surface 1A is fixed, The combined speed of the directional speed (revolution speed) and the crushing speed of the grinding medium directly becomes the speed difference between the inner wall surface 1A and the grinding medium. Therefore, the speed difference between the crushing medium and the inner wall surface 1A becomes extremely large, and the grinding action by the action of the crushing medium when moving on the inner wall surface 1A becomes extremely strong.

Further, the pulverizing medium that has left the inner wall surface 1A and has landed on the dish surface 2A rolls down smoothly along the dish surface 2A, so that the inner wall surface 1A is moved by the motion of rolling down the dish surface 2A. It is possible to convert the potential energy obtained when running up to the kinetic energy in the radial direction, so that the energy once applied to the grinding medium can be effectively used for the peeling action without consuming it unnecessarily. . Furthermore, when descending along the dish surface 2A, the grinding medium slides on the dish surface 2A, so that grinding or peeling is performed even during this descending motion.

The crushing action in the crushing chamber described above is preferably performed on ceramics and the like with a hard and brittle material,
When pulverizing materials with remarkable adhesiveness, such as limestone, mirabilite, alumina, magnesium oxide, and zirconia (synthesized by the synthetic method), these fine powders may be crushed on the crushing surface of the crusher as the crushing progresses. Since the inner wall surface, in this embodiment, adheres to the surface of the liner of the rotating dish or the stationary ring to grow and develop, further crushing does not proceed, and the adhered layer serves as a cushion layer to weaken the crushing force, and the crusher system Disruption to the outside is suppressed, which causes problems in crushing.

However, in the present invention, in addition to the usual spherical balls made of steel or ceramics, a grinding medium having an irregular shape such as a cube is also loaded in the apparatus, so that during the spiral movement of the centrifugal flow grinding apparatus described above, The crushed raw material attached to the crushed inner surface is scraped off just by acting as a scraper by sliding along the crushed inner surface of the edge portion (corner angle) or ridge of these cubes. Therefore, even if the crushing raw material adheres to the crushing inner surface, the growth and development are hindered and the formation of the cushion layer is suppressed, so that the crushing efficiency is also improved. FIG. 4 shows the changes over time in the amount of pulverization of spherical balls only (A in the figure) and mixed irregular-shaped media (B in the figure), clearly showing that B is superior to A, and B shows a marked decrease in capacity. Not shown.

FIG. 3 shows a typical example of the irregular-shaped grinding medium that can be used in the present invention. (A) is a cube, (b) is a rectangular parallelepiped, (c) is a cylinder, (d) is a quadrangular pyramid, (e). Indicates a polyhedron (hexahedral), (f) indicates a curved surface, and (g) indicates a polyhedron (diamond shape). In addition to the above, if it has an edge (cusp point) or a ridgeline, it can be used as the irregular-shaped grinding medium of the present invention.

The mixing ratio of the irregular medium to the spherical medium can be selected from 10 to 60% with 100% as a whole.

Fig. 5 shows the relationship between the mixing ratio and the crushing ability, and the best result was obtained at about 35%.

Although the crushing proceeds as described above, the discharge of the material after the crushing is as follows. That is, pipe 3
5. If an appropriate amount of air is introduced into the crushing chamber 23 from the gas chamber 36 and the gap 29 and the centrifugal fluidizing crushing as described above is continued for a certain period of time, the crushing raw material is separated by grinding or peeling, The powder is discharged from the discharge pipe 22 together with the air. A classifier may be provided at the top of the centrifugal fluidizer of the present invention to discharge only the required fine powder.

Since gas is blown into the crushing raw material and the crushing medium being centrifugally fluidized through the gap 29, the fine powder of the crushing raw material is immediately conveyed by air flow and discharged. Therefore, the fine powder once peeled off does not adhere to the base substance again.

Of course, the air can be introduced into the crushing chamber 23 by suction from the discharge pipe 22 instead of by blowing air from the pipe 35.

In this way, the pulverized raw material having remarkable adhesion can be pulverized with certainty, and the high-purity pulverized raw material can be efficiently obtained.

[Effects of the Invention] As described above, according to the operation method of the centrifugal fluidizing and pulverizing apparatus of the present invention, since the irregularly shaped pulverizing medium is mixed in the pulverizing medium, the cleaning for removing the coating layer adhering to the inner surface of the pulverizing is performed. It has an effect, and by this, it is possible to suppress the generation of the cushion layer on the inner surface of the pulverization and enhance the pulverization effect, and at the same time, to improve the fine pulverization of the pulverization material.

[Brief description of drawings]

FIG. 1 is an overall side view of a centrifugal fluidizing and pulverizing apparatus, FIG. 2 is a longitudinal sectional view of essential parts, FIG. 3 is a schematic perspective view of various irregularly shaped pulverizing media, and FIG. Relationship diagram, fifth
The figure is a relationship diagram between the mixing ratio of the odd-shaped medium and the crushing ability. 1 ... Stationary ring, 2 ... Rotating pan, 1A ... Inner wall surface, 2A ... Plate surface, 3 ... Plate, 4 ... Casing, 14 ... Reducer, 17 ... Motor, 18 ... Lid member , 22 …… discharge pipe, 23 …… grinding chamber, 24 …… input pipe, 29 …… gap.

Claims (2)

[Claims] 1. A rotation having a shape in which a rotation axis is oriented in a vertical direction, at least a central portion has a dish surface whose diameter is expanded downward, and a longitudinal cross section of the dish surface is curved in a concave shape. It has a freely rotatable circular dish and at least an upper part of which has an inner wall surface that reduces in diameter upward, and the inner wall surface has a shape in which a vertical cross section is curved in a concave shape. A stationary ring that is installed and stationary, and the plate surface of the rotary plate and the inner wall surface of the fixed ring form a continuous smooth surface except for a minute gap between the rotary plate and the fixed ring. A method of operating a centrifugal fluidizing and pulverizing apparatus, wherein a pulverizing medium having an irregular shape other than a spherical shape is mixed as the pulverizing medium. 2. The method for operating a centrifugal fluidized pulverizer according to claim 1, wherein the irregularly-shaped pulverization medium is any one of a cube, a rectangular parallelepiped, a cylinder and a polygonal pyramid.