JP2002361179A - Classifier for glass powder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple classifier for solving the problem that when glass powder produced by a crusher such as a ball mill is screened and classified by using a vibrating screen, the meshes of the screen are clogged with fine particles of glass to make screening and classification difficult so that the fine particles should be removed by previous classification. SOLUTION: The powder classifier which is provided with a conveyer for conveying the powder entrained in an air current through piping, the first powder recovery part having a classifying plate which is arranged vertically or forward slantingly to the air current and shuts out the conveyed powder, the second powder recovery part for recovering the second powder which passed through the first powder recovery part, and an air volume adjusting valve fitted to piping for connecting the first powder recovery part with the second powder recovery part and classifies the powder while the powder is conveyed pneumatically is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a classification apparatus for glass powder, and more particularly to a dry classification apparatus for performing classification using an air flow.

[0002]

2. Description of the Related Art As a highly reliable method of classifying powder particles, there is known a sieving classification method in which particles are passed through a sieve mesh one by one using a sieve. In general sieving and classification, there is no problem when the particle size is larger than a certain level, but there is a problem that as the particle size becomes smaller, clogging occurs.

[0003] For classifying glass powder products crushed by a crusher such as a ball mill, a vibrating sieve is used.
Although the method of sieving using is used, small particles of glass contained in the powdery product cause clogging of the sieve and there is a problem that predetermined sieving cannot be performed.

[0004] In a glass powder product or the like crushed by a crusher such as a vibrating ball mill, clogging of a sieve is particularly likely to occur due to a relatively large amount of small particles and an irregular shape of the small particles. .

[0005] Therefore, in order to classify and classify a glass powder product crushed by a crusher such as a ball mill using a sieve, small particles are preliminarily removed before using the sieve. Preferably, a step is provided.

As a classifier for preliminarily separating such small particles, for example, a classifier by wind power is considered.
In addition to the large size, maintenance is troublesome, and the cost is high.

A classifier using such a wind force is described in, for example, Japanese Patent Application Laid-Open No. Hei 8-24792. This classifier separates wood chips and paper chips from crushed materials such as houses by wind power, and separates them according to particle size.
Classification is performed as follows.

[0008] First, the crushed material is transported by a belt conveyor and dropped by an inclined chute. During the falling, the air blown from the back of the inclined chute causes the light-weight material in the crushed material to float and be sucked into the duct. Heavy objects that do not float by the air are immediately dropped and sorted by the inclined chute. For the light-weight material sucked into the duct, a relatively heavy thing is stored in the storage container at the divided suction port provided in the middle of the duct, and the relatively light thing is further sucked into the duct. It will be contained.

As can be seen from this example, the classifier using wind power has many difficulties in classifying glass powder products, for example, the structure is large and the cost is large.

[0010]

SUMMARY OF THE INVENTION The glass powder classifier of the present invention pays attention to the above-mentioned problems of the prior art, and efficiently separates small particles contained in the glass powder with a simple and compact structure. And a classifier capable of obtaining powdery particles having a required particle size.

[0011]

SUMMARY OF THE INVENTION A glass powder classifier of the present invention is a powder classifier for classifying a powder product in the middle of conveying the powder product by using wind power. And a first powder product collection unit having a classifier that is disposed upright or inclined forward with respect to the air flow and that blocks the conveyed powder product, and the first powder product. A second powder product collection unit that collects the second powder product that has passed through the collection unit;
And a flow rate adjusting valve provided in a pipe connecting the second powder product recovery section to the second powder product recovery section.

In the apparatus for classifying glass powder products of the present invention,
The carrier is provided with, for example, a blower for generating an airflow in the pipe, and this blower may be installed on the upstream side of the airflow, or may be installed on the downstream side, and these are used in combination. You may. As a simple method, an air purifier may be arranged at the most downstream side, and the suction function of the air purifier may be used as an airflow generator, and the exhaust air of the classifier may be cleaned.

In the apparatus for classifying glass powder products of the present invention,
The classifying plate is a partition plate hanging down toward the inlet side in a first powder product collecting section, for example, a powder / particle product falling tank having an inverted frustum-shaped inner surface, and an air flow passage below the partition plate. It is what left. The particles of the glass powder conveyed by the airflow and sent to the first powder product recovery unit are rebounded by the classifying plate, and the flow of the particles is directed downward. As a result,
The glass particles having a relatively large particle size arrive at the first powdered product recovery section, settle, and are recovered. On the other hand, relatively small particles in the glass powder product pass through the first powder product recovery section in the airflow from the lower passage without settling. The small particles that have passed here are collected and collected by the second powder product collection section. As the second powder product collection unit that collects and collects small particles, for example, a collection device using a centrifugal force such as a cyclone can be used.

By using the apparatus for classifying glass powder products of the present invention in this way, glass powder products from which small particles have been removed can be recovered from the first powder product recovery section. Since the small glass powder that causes clogging is removed from the collected glass powder product, the classification step using a sieve can be performed with high productivity.

The glass powder classifier of the present invention is characterized in that an air flow regulating valve is disposed between the first powder product recovery section and the second powder product recovery section. There is.
In the glass powder product classifying apparatus of the present invention, the air volume is controlled and adjusted mainly by a carrier that generates an air flow. However, since a relatively large resistance to the air flow exists between the transporter that generates the air flow and the first powder product collection unit,
To finely adjust the air volume of the first powder product collection section,
It is not always sufficient to adjust the air volume of the transfer device that generates the air flow. In the present invention, as a result of arranging and adjusting the air flow control valve in the small particle discharge pipe between the first powder product recovery unit and the second powder product recovery unit, fine air flow control is achieved. This makes it possible to finely adjust the particle size of the glass powder product collected in the first powder product collection section.

In the apparatus for classifying glass powder products of the present invention, the first powder product recovery section has an approximately inverted truncated frustum having an inlet on the side wall and an outlet on the upper side remote from the inlet. A collecting part main body on the inner surface, and 4
It is preferable that the classifier be made up of a classifying plate that is suspended upright or inclined forward in the range of 5 to 90 °.

If the classifying plate is at an angle of less than 45 ° with respect to the horizontal plane, the particles colliding with the classifying plate will not sufficiently stall and will pass through the first powdery product recovery unit. Classification plate is 90 ° to horizontal plane
If it exceeds, the resistance is too large, and small particles are prevented from passing through the first powder product recovery section. For more efficient classification, the angle is preferably 60 to 90 °.

Further, in the glass powder product classifying apparatus of the present invention, the classifying plate of the first powder product collection section has a shielding degree of 60%.
It is preferably about 80%.

Here, the degree of shielding is the ratio of the area of the classifying plate that blocks the passage to the effective cross-sectional area of the passage when there is no classifying plate. If the degree of shielding is less than 60%, the particles do not stall sufficiently and pass through the first powder product recovery section, and if the degree of shielding exceeds 80%, the resistance is too large, and the small particles are less than the first powder. This will prevent it from passing through the product collection section.

The number of the classifying plates used in the glass powder product classifying apparatus of the present invention can be increased. However,
In the glass powder product classification device of the present invention, the flow of the powder product particles conveyed into the first powder product recovery unit by the wind is bent downward, and only the small particles transferred again by the wind pass. It is preferable that the structure of the classifying plate be simple for maintenance of the apparatus. For this reason,
From the viewpoint of its function, a preferable number of sheets is one each on the inlet side and the outlet side of the first powdery product collecting section.

[0021]

FIG. 1 is a view schematically showing one embodiment of a glass powder product classifying apparatus according to one embodiment of the present invention. In FIG. 1, a glass powder product 12 obtained by pulverization by a vibrating ball mill 11 is conveyed by wind power,
It is guided to the first powder product recovery section 14 by the powder product supply pipe 13. As the powder supply pipe 13 used here, a pipe having wear resistance, for example, a wear-resistant hose for transportation is used.

Here, the suction function of the dust collector 22 is used to generate an air flow for conveying the powdery product as a conveyor. In addition, an inverter control provided in the dust collector is used for controlling the air volume. By the inverter control of the air volume in the dust collector, it is possible to maintain a substantially constant air volume by the feedback control even if the load resistance fluctuates. Further, since the air volume adjustment valve 17 is provided between the first powder product collection unit and the cyclone 19, the air volume adjustment in the first powder product collection unit 14 is directly finely adjusted by the air volume adjustment valve. be able to.

The first powdered product recovery section 14 has a classification plate 151
And 152 are provided at an angle α with respect to the horizontal plane, and are conveyed by an air current to
The particles of the glass powder sent to the
The direction of the flow is changed downward while colliding with 1,152 and rebounding. At this time, those having a relatively large particle size in the powder product reach downward, and are collected from the outlet 16 of the first powder product collection unit.

On the other hand, among the powdery product particles, those having a small particle size get into the airflow again during their arrival, and pass through the first powdery product recovery unit 14. The small particles that have passed through the first powder product recovery section 14 reach the cyclone 19 through the small particle discharge pipe 18, where they are swirled and collected by centrifugal force.
Is stored in the collection container 20 of the powder product collection section.

The particle size of the particles recovered from the outlet 16 of the first powder product recovery section can be changed by adjusting the air volume. At this time, the air volume is adjusted by setting the air volume on the dust collector side, and finely adjusting the setting for the air volume of about 10% of the air volume set on the dust collector side using the air volume adjusting valve. In this manner, the particle size of the particles collected from the outlet 16 of the first powdered product collection section can be finely changed.

The air discharged from the cyclone 19 is sent to a dust collector 22 through a pipe 21, where the dust remaining in the exhaust gas is further removed and purified, and the air is discharged from a discharge port 24 through a pipe 23 to the outside. Is discharged.

(Embodiment) The crushed glass powder was classified by the apparatus schematically shown in FIG. Flake-shaped glass flakes (1-5 mm square, thickness 50-100
μm and a bulk density of about 0.6) and glass powder which has already been pulverized and which has a large particle size in a sieving step in a sieving process and is again pulverized. After crushing the powder to a particle size of about 0.5 to 120 μm, the crushed powder is placed in a carrier airflow of about 18 m ³ / min.
4 was transferred.

In the first powdery product recovery section 14, a classifier 151 on the inlet side and a classifier 152 on the outlet side are provided one by one.
By changing the angle and the degree of shielding, the rate at which particles having a size of 20 μm or more were classified and collected in the large particle collection container was examined.

First, the degree of shielding of the classifying plates 151 and 152 is kept constant at 70% on both the inlet side and the outlet side, and the angle α between the classifying plates and the horizontal plane is changed, so that the outlet 16 of the first powdery product collecting section is changed. Table 1 shows the results obtained by examining the recovery of particles having a particle size of 20 μm or more from.

[Table 1]

From the results shown in Table 1, the entrance side classification plate 151
The angle α between the horizontal plane and the horizontal plane is between 45 ° and 90 °,
It can be seen that the recovery rate of particles having a size of 20 μm or more in the powder product recovery section becomes higher. Similarly, the angle between the outlet-side classifying plate 152 and the horizontal plane was preferably from 45 ° to 90 °.

Next, the angle between the horizontal surfaces of the classifying plates 151 and 152 is fixed at 75 ° on both the inlet side and the outlet side, and the degree of shielding of these classifying plates is changed so that the outlet 1 of the first powdery product collecting section is changed.
Table 2 shows the results obtained by examining the recovery of particles having a size of 20 μm or more from No. 6.

[Table 2]

From the results shown in Table 2, the entrance-side classifying plate 151
Is less than 60%, and 20
It can be seen that the recovery rate of particles having a size of μm or more increases. Similarly, the degree of shielding of the outlet-side classification plate 152 is 60%.
The above was good.

Further, the classification plates 151 on the entrance side and the exit side,
It was found that when the shielding degree of 152 exceeded 80%, the resistance to the generation of airflow increased, and the classification ability rapidly decreased.

Next, the angle between the horizontal planes of the classifying plates 151 and 152 was set to 75 °, the degree of shielding was set to 70%, the air volume was set by the dust collector 22, and the air volume was finely adjusted by the air volume adjusting valve. As a result, the particle size of the particles collected in the first powder product collection section could be finely changed over a wide range.

It should be noted that the embodiments and examples shown here are merely examples to specifically explain the present invention, and the scope of the present invention is not limited to these examples. All modifications and changes belonging to the claims of the present invention are within the scope of the present invention.

[0036]

According to the present invention, if the classification is performed using the glass powder classification apparatus of the present invention to remove small particles and then sieved and classified,
It is possible to prevent clogging of the sieve and to classify the glass powder with high productivity. In addition, since the glass powder classification apparatus of the present invention has a simple and compact structure, it can be configured at low cost, has easy maintenance, and has a low possibility of failure. Further, the air volume can be finely adjusted by an air volume adjusting valve disposed between the first powder product recovery unit and the second powder product recovery unit, and the particle size of the powder product particles to be classified is thereby adjusted. Can be changed finely.

[Brief description of the drawings]

FIG. 1 is a view schematically showing one embodiment of a glass powder product classifying apparatus of the present invention.

[Explanation of symbols]

11: Vibration ball mill, 12: Glass powder product, 1
3 ... powder supply pipe, 14 ... first powder product recovery section,
151: Classifier on the inlet side, 152: Classifier on the outlet side, 1
6: take-out port of the first powder product collection section, 17: air flow control valve, 18: small particle discharge pipe, 19 cyclone, 20
... Collection container of the second powder collection section, 21.
…… Dust collector (transporter that generates airflow), 23 …… Piping,
24 ... Exhaust port.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) // B02C 23/08 B02C 23/08 Z 23/20 23/20

Claims (3)

[Claims] An apparatus for classifying a powder product on the way of transporting the powder product using a wind force, comprising: a transfer device for transferring a powder product placed in an air flow through a pipe; A first powder product collection unit provided with a classifying plate that intercepts the conveyed powder product and is arranged forward, and a second powder product that collects the second powder product that has passed through the first powder product collection unit. 2. A glass powder, comprising: a powder product collection unit of No. 2; and an air volume adjusting valve provided in a pipe connecting the first powder product collection unit and the second powder product collection unit. Body classifier. 2. A substantially inverted truncated frustum-shaped inner surface of the first powdered product recovery portion, the recovery portion main body having an inlet on a side wall and an outlet on an upper side remote from the inlet, and the main body. 2. A classifying plate which is vertically or slanted forward in a range of 45 to 90 [deg.] Toward the inflow port.
The glass powder classification apparatus according to the above. 3. The glass powder product classification device according to claim 2, wherein the degree of shielding of the classification plate of the first powder product collection section is 60 to 80%.