JPS5943228B2 - Wind classifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air classifier for separating classified raw materials into fine powder and coarse powder, and particularly to a classifier for ultrafine powder.

Conventionally, various wind classifiers have been developed which are selectively used depending on the physicochemical properties of the classified raw material, desired classification point, processing amount, etc.

However, when classifying ultrafine powder of several microns, all conventional wind classifiers have the disadvantage of poor classification accuracy.

In particular, when processing classified raw materials with a high dust concentration (e.g., powder concentration of O, 2 kg/Ti or more), conventional wind classifiers have problems with classification accuracy, power characteristics, capacity characteristics, etc. All of the indispensable characteristics needed for this will deteriorate.

In addition, as the size of the wind classification device increases, the classification point increases, making it virtually impossible to classify ultrafine powder. A large number of classification devices had to be used, which inevitably resulted in poor efficiency in terms of equipment and classification characteristics.

An object of the present invention is to eliminate the above-mentioned limitations or drawbacks and, in particular, to provide an air classifier that can efficiently, easily, and accurately process large quantities of ultrafine classified raw materials.

In order to achieve this object, the classification device of the present invention provides a rotating rigid shaft approximately at the center of a substantially spiral cylindrical casing, a rotating plate is mounted near the lower end of the rotating rigid shaft, and a rotary plate is mounted near the lower end of the rotating rigid shaft, and A raw material inlet is provided in the casing, a horizontal dispersion plate that rotates integrally with the rotating rigid shaft is provided adjacent to the top and at a position where the powdered raw material falls from the raw material inlet, and an air inlet is provided in the casing in the tangential direction thereof. protrudingly provided in the casing, a plurality of vertical guide vanes are arranged in the casing along the inner wall thereof and concentrically with the rotating rigid shaft, and a classification chamber is formed by the vertical guide vanes, the dispersion plate, and the rotary plate; a plurality of eddy current adjustment pieces each having one end fixed to the rotating plate and the other end fixed to the dispersion plate, the classification chamber being partitioned by a plurality of annular horizontal straightening stages rotating together with the rotating shaft, and an inner wall of the casing. and an air partition plate that partitions the space between the vertical guide vanes at the same level as the horizontal rectifying partition plate, and a plurality of blades or rollers on the outer edge of the horizontal rectifying partition plate or on the outer edge of the horizontal rectifying partition plate and the rotary plate. A coarse powder discharge pipe is provided in a portion of the casing adjacent to the raw material inlet and the vertical guide vane, and a fine powder discharge pipe is provided in a lower part or an upper part of the casing, or in the upper part and the lower part. It is configured with a discharge pipe.

The present invention will be explained below based on the drawings.

In the first embodiment shown in FIGS. 1 and 2, 1 is a substantially spiral-shaped rigid casing, and an air inlet 2 is provided tangentially projecting from a side wall 1a of the casing. Further, a raw material inlet 3 is provided at the center of the top of the casing 1. Of course, the raw material inlet 3 is not limited to one as shown in the figure, but may be a plurality of dispersed raw material inlets. Reference numeral 4 denotes a rotating hard shaft that is provided approximately at the center of the casing 1 and passes through the raw material inlet 3, and 5 is a hollow rotary plate that also serves for dispersion and classification, and is arranged so as to approximately coincide with the lower end surface 1b of the casing 1. It is mounted on the lower end of the rotating rigid shaft 4 via spokes 5a.

A fine powder discharge pipe 6 whose upper end is concentric with the rotary plate 5 extends downward from the lower end surface 1b of the casing 1 to the rotary plate 5. 5b
It communicates with the classification room 9, which will be described later. Casing 1
A horizontal dispersion plate 7 is provided adjacent to the top thereof and at a position where the raw material falls from the raw material inlet 3 so as to rotate integrally with the rotary rigid shaft 4 and the rotary plate 5.

As an example, the dispersion plate 7 is a disk whose center portion is fixed to the rotating rigid shaft 4. 8 is a truncated cone-shaped collision member provided on the inner wall of the casing 1 between the top of the casing 1 and the dispersion plate 7, and the raw material falling from the raw material inlet 3 collides with the dispersion plate 7.
The particles are dispersed, collide with this collision member 8, change the traveling direction downward, and are sent to the classification chamber 9 from the entire circumference.

10, . . . are a plurality of vertical guide vanes, the inner and outer edges of which are located on a cylinder concentric with the rotating hard shaft 4, and arranged so that the outer edges closely follow the casing 1.

The vertical guide vanes 10, . . . are inclined at the same angle and in the same direction with respect to the cylinder in which the inner edges of these guide vanes 10, . Guide wing 10,
This inclination angle can be adjusted by a lever 11 provided at the upper part of the casing 1. The classification chamber 9 is a cylindrical space formed by a cylinder having an inner edge of the vertical guide vanes 10, the rotary plate 5, and the dispersion plate 7.

The lower end portion of the casing 1 adjacent to the guide vanes 10, . . . and the air inlet 2 (hereinafter referred to as the “coarse powder collecting portion”).

) 12, a coarse powder discharge pipe 13 projects downward. Casing 1 is placed in a position roughly symmetrical to the air inlet 2 of casing 1.
A secondary air intake port 14 may be provided which extends tangentially from the classification chamber 9. If this is provided, the amount of classified air in the classification chamber 9 can be adjusted.

A plurality of vertical vortex adjustment pieces (hereinafter referred to as eddy current adjustment pieces).
) 16, the horizontal rectifying partition plate 17 of the classification chamber 9, and the annular air intake chamber 18 defined by the inner wall of the casing 1 and the cylinder with the outer edge of the guide vanes 10, . An annular air partition plate 19 is provided. That is, the vortex current adjustment piece 16 has one end fixed to the horizontal dispersion plate 7,
and the other end is fixed to the rotary plate 5, and the casing 1
They are arranged in a cylindrical shape concentric with the rotating rigid shaft 4.

The rectifying partition plate 17 has a donut shape, and its outer edge is connected to the guide blades 10,
... are fixed at regular intervals in the vertical direction, dividing the classification chamber 9 into a plurality of small sections.

The air partition plate 19 is located at the same level as the corresponding rectifying partition plate 17 and partitions the air intake chamber 18 into the same number of chambers as the classification chamber 9. Furthermore, blades 20 whose tips slide into or approach the outer edge of the lower end surface 1b of the casing 1 are provided on the outer edge of the rotary plate 5 at equal intervals in the circumferential direction.

Further, a classified raw material crushing/distributing means 100 is provided at the outer edge of the rectifying partition plate 17. Classified raw material crushing/dispersing means 10
0 is a plurality of blades, preferably a plurality of rollers.

6 and 7 respectively show enlarged views around the blades 21 and rollers 22 as the classified raw material crushing and dispersing means 100.

The outer peripheral surfaces of the blades 21 and rollers 22 are connected to the corresponding air partition plate 1.
In particular, the roller 22 is configured to roll on an annular receiving portion 19a extending radially inward from below the inner circumferential surface of the air partition plate 19. There is.

Slots 21b, 22b extending in the longitudinal direction are formed in shafts 21a, 22a of the blades 21 and rollers 22, which are inserted in the radial direction into the rectifying partition plate 17, and bolts and nuts 21c, 22c are inserted into these slots 21b, 22b. It may be inserted and fixed to the rectifying partition plate 17. In this way, the blades 21 and rollers 22 can be moved radially outward of the rectifying partition plate 17 by centrifugal force. The blades 21 and the rollers 22 promote the disintegration action of the classified raw material in which fine powder is attached to the coarse powder or the classified raw material that has secondary agglomeration between them and the partition plate 19 provided in the air intake chamber 18, and improve the dispersibility of the classified raw material. By increasing the particle size, classification accuracy in the ultra-fine powder range is improved. still,
The roller 22 can also be replaced with the blade 20 attached to the rotating plate 5. Reference numerals 15, . . . are insertion dampers attached to the fine powder discharge pipe 6, and by performing a squeezing action, the classification point can be adjusted or the classification accuracy can be improved.

Next, the operating state of the classification apparatus having the above configuration will be explained.

The rotating rigid shaft 4, the rotating plate 5, and the dispersion plate 7 are rotated together by a driving device (not shown).

Air is supplied from the air inlet 2 at an appropriate speed by, for example, a blower (not shown) to the inclined guide vanes 10, . . .
・Flows into the classification chamber 9 while drawing a vortex along the direction determined by. If a secondary air intake port 14 is provided, it is possible to replenish air therefrom and adjust the amount of classified air in the classification chamber 9.

The raw material inputted from the raw material inlet 3 is dispersed by the rotation of the distribution plate 7, the direction is changed downward by the collision member 8, and the raw material is sent from the entire circumference of the collision member 8 to the classification chamber 9, and the air from the air inlet 2 is join with.

The rotating airflow of the raw material flowing into the classification chamber 9 in a vortex is strengthened by the rotation of the dispersion plate 7 and the rotating plate 5, and the directions of the outward centrifugal force and the radially inward air resistance are opposite to each other. You will receive two forces at the same time. If the particle size at which these two forces are balanced is called the classification point, then particles below the classification point, that is, fine powder, will have greater inward air resistance than outward centrifugal force, and will ride the airflow and move toward the center. direction, the fine powder is sent into the fine powder discharge pipe 6, and collected by a separately provided collector (not shown). On the other hand, coarse powder having a particle size equal to or larger than the classification point has a centrifugal force greater than the inward air resistance, flows along the inside of the guide vanes 10, .
and is collected through the coarse powder discharge pipe 13. In this way, a large amount of ultra-fine powder raw material can be classified accurately and efficiently using one classifier. In addition, by dividing the classification chamber 9 into a plurality of small chambers arranged vertically, a large classifier is used to prevent the powdery raw material above the classification chamber 9 from descending due to gravity. Suitable for processing a large amount of classified raw material, the vortex current regulating piece 16 serves to prevent disturbances in the horizontal plane of the vortex.

In other words, the air containing the powder raw material to be treated flows from the outer periphery to the center inside the classification chamber 9 while drawing a vortex. It is difficult to generate an ideal vortex flow, and no matter how you adjust the rotation speed, feed rate of raw materials, particle size distribution, etc., turbulence will occur in the vortex flow, making sharp or accurate classification impossible.

However, the vortex flow adjusting piece 16 and the rectifying partition plate 17 solve this drawback, and even in a large-sized device, sharp classification is possible without causing turbulence in the vortex flow. 3 shows the eddy current adjustment piece 16 installed upright on the outer edge of the rotary plate 5, FIG. 4 shows the eddy current adjustment piece 6 installed close to the center of the rotary plate 5, and FIG. is provided between the outer edge and the center of the rotary plate 5, and whereas in FIGS. 3 and 4, the vortex flow adjustment piece 6 is oriented toward the rotation rigid shaft 4, it is inclined.

The radial position, number, and inclination angle of these eddy current adjusting pieces 16 on the rotary plate 5 are determined according to the desired classification point, the size of the classification device, the rotation speed of the rotary plate 5, etc. Using these, it is also possible to set a desired classification point.

Furthermore, by installing the rectifying partition plate 17, it is easy to set up a classifier that can adequately accommodate constraints such as the installation location and area of the classifier, and the size of the entire classifier is small relative to the throughput of classified raw materials. It is economical because sufficient classification accuracy can be obtained without excessively increasing the size.

The air partition plate 19 provided in the air intake chamber 18 is also the rectifying partition plate 1.
7, and the synergistic effect with the rectifying partition plate 17 makes it possible to classify ultrafine raw materials with sufficient classification accuracy.

The blades 20 provided on the outer edge of the rotary plate 5 have the function of crushing and dispersing the classified raw material that has been deposited on the outer edge of the lower end surface 1b of the casing 1 due to fine powder adhering to coarse powder or secondary agglomeration. Together with the effects of the eddy current adjustment piece 16, the rectifying partition plate 17, and the air partition plate 19, this improves the classification accuracy of the ultrafine raw material.

FIG. 8 shows a configuration in which a center hole is formed in the dispersion plate 7 of the classification apparatus shown in FIGS. 1 and 2 to form a doughnut-like or annular shape, and another fine powder discharge is communicated with the classification chamber 9 through this center hole. A tube 6' is provided to protrude upward from the top of the casing 1.

A disk-shaped horizontal shielding plate 23 whose center portion is fixed to the rotary rigid shaft 4 at substantially the center height of the classification chamber 9 completely partitions the classification chamber 9 into upper and lower parts.

A plurality of raw material inlets 3 are provided surrounding the fine powder discharge pipe 6'.

In this wind classifier, especially the upper and lower fine powder discharge pipes 6 and 6
' fine powder with different classification points can be collected.

That is, by providing an appropriate number of vortex flow adjusting pieces 16 and rectifying partition plates 17 in the classification chamber 9, which is completely partitioned from the upper and lower sides by the shielding plate 23, fine powder of the desired classification point can be collected from the upper and lower fine powder discharge pipes. Obtainable. Therefore, together with the coarse powder recovered from the coarse powder discharge pipe 13, it is possible to simultaneously classify powder and granules having a plurality of particle sizes. 9th
The figure shows the fine powder discharge pipe 6 at the bottom with the same purpose as the classification device shown in Figure 8.
By using double tubes for , r, simultaneous classification of multiple grain groups was made possible.

The position of the coarse powder collection section 12 is the final position after the classified air has circulated through the classification chamber 9 from the inlet 2, as shown in FIG. The height is preferably 1/6 to 1/3 of the height of the classification chamber from the bottom plate. Since the coarse powder collecting section 12 is provided at the only location in the casing 1, the coarse powder can be collected intensively, and the dispersion of the ultrafine powder is sufficiently strengthened, thereby improving the dispersion efficiency.

In addition, only one thin coarse powder discharge pipe is required, making the wind classifier more compact and reducing the manufacturing cost and initial cost of the device. As described above, the wind classifier of the present invention classifies raw material and air into layers through vertical guide vanes, air partition plates, and rectifying partition plates by means of a rotary plate fixed to a rotating rigid shaft within a spiral casing. A crushing/dispersing means is provided to introduce the classified raw material as a vortex, separate the classified raw material into fine powder and coarse powder at a predetermined classification point according to the centrifugal force applied to the classified raw material, and promote the crushing and dispersion of the classified raw material. The coarse powder is collected intensively in the only coarse powder collecting section provided in the interior adjacent to the raw material inlet and the vertical guide vane, and the fine powder is taken out from the classification chamber through the fine powder discharge port leading to the classification chamber. As a result, the dispersion of the ultrafine powder is strengthened, the dispersion efficiency is improved, and a large amount of ultrafine powder raw materials can be easily, accurately, and economically classified.

[Brief explanation of the drawing]

The drawings show each embodiment of the classification device according to the present invention.
The figure is a cross-sectional view, FIG. 2 is a vertical cross-sectional view, FIGS. 8 and 9 are longitudinal cross-sectional views of other embodiments, and FIGS. 3 to 5 are schematic diagrams showing examples of mounting the vortex adjustment piece. , FIG. 6, and FIG. 7 are partially enlarged views mainly showing an embodiment of the classified raw material crushing and dispersing means. 1...Casing, 2...Air inlet,
3... Raw material inlet, 4... Rotating rigid shaft, 5
... Rotating plate, 6, 6', 6pe ... Fine powder discharge pipe, 7 ... Dispersion plate, 8 ... Collision member, 9 ... ... Classification room, 10 ... Guide wing, 1
1...Lever 12...Coarse powder collection part,
13...Coarse powder discharge pipe, 14...Secondary air intake port, 15...Insert damper, 16...
... Eddy current adjustment piece, 17 ... Rectification partition plate, 1
8...Air intake chamber, 19...Air partition plate, 20...Blade, 21...Blade, 2
2...roller, 23...shielding plate, 10
0... Classified raw material crushing and dispersing means.

Claims (1)

[Scope of Claims] 1. A rotating vertical shaft is provided substantially at the center of a casing having a substantially spiral-shaped horizontal cross section, and a horizontal rotating plate is mounted near the lower end of the casing on the vertical shaft, A raw material inlet is provided at the top of the casing, and a horizontal dispersion plate that rotates integrally with the rotating vertical shaft is provided adjacent to the top of the casing and at a position where the granular raw material falls from the raw material inlet,
An air inlet is provided in the casing protruding in the tangential direction thereof, and a plurality of vertical guide vanes are arranged in the casing along the inner circumference thereof and concentrically with the rotational vertical axis, and the vertical guide vanes and the dispersion plate A classification chamber is formed, a plurality of eddy current adjustment pieces are fixed at one end to the rotating plate and the other end to the dispersion plate, and the classification chamber is formed by a plurality of annular horizontal straightening plates that rotate together with the rotating shaft. a partition, an air partition plate that partitions the space between the inner wall of the casing and the vertical guide vane at the same level as the horizontal rectification partition plate; A classified raw material crushing/dispersing means consisting of a plurality of blades or rollers is provided in the casing, a coarse powder collection section is provided in a portion of the casing adjacent to the air inlet and the vertical guide vanes, and the coarse powder is removed from the coarse powder collection section. A wind classifier characterized in that a discharge pipe is extended, and a fine powder discharge pipe is provided at a lower part or an upper part of the casing, or at the upper part and the lower part. 2 A disk-shaped horizontal shielding plate is provided in the classification chamber to completely divide the classification chamber into two upper and lower chambers, and another fine powder discharge pipe is provided at the top of the casing that communicates with the upper chamber of the classification chamber. The wind classifier according to claim 1, characterized in that: