JPS6372362A - Jet air flow type crusher - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to a jet stream type pulverizer, and more particularly to a jet stream type pulverizer used for pulverizing, crushing, and polishing powder using a jet stream. It is.

(Background of the Invention) Conventionally, jet stream crushers have had the advantage of being easier to maintain and operate compared to other crushers, and have also been compatible with air classifiers that are sometimes connected to the downstream stage. It has become widely used in recent years due to its good matching properties, and also because it generates almost no heat, which can be a problem during grinding.
It is said to be particularly useful for pulverizing powders with poor heat resistance (such as plastic powders). In addition to pulverizing powder in a narrow sense, the jet air flow type pulverizer may also be used to break up aggregated powder or remove foreign matter stuck to the surface of the powder.

Conventionally, such a jet stream type crusher is equipped with a nozzle that ejects a jet stream in an inward tangential direction from a circular wall surface so as to swirl and flow the powder along the inner surface of the circular wall surface. This is a type in which the powder is drawn into a jet stream while causing the powder to blow against each other (hereinafter referred to as the swirling flow type). One is a type that increases the collision force between the powder particles (hereinafter referred to as the opposing crushing nozzle type), and the other type is a type that blows a jet air stream that entrains the powder against a hard wall surface, etc. (hereinafter referred to as the object collision type). ), a jet stream is ejected from a part of the wall surface of the gas phase flow path while the powder is in a gas phase flow inside an oval gas phase flow path, and the powder is introduced into this jet stream. Jet stream type crushers are known, such as a type in which powder is rolled in and crushed by collision of powder particles (hereinafter referred to as a jet-o-mizer type).

However, several problems have been pointed out with these types of pulverizers that have been proposed and put into practice.

For example, the above-mentioned swirl flow type pulverizer is suitable for pulverizing a very small amount, but it does not have a mechanism for extracting powder (generally called a classification mechanism) that takes out the pulverized fine particles from the center of the swirl flow. Due to its structure, if the throughput is increased, a considerable amount of powder with a large particle size will also be taken out at the same time, making it structurally unsuitable for providing processing capacity as a crusher on an industrial scale. There are problems in terms of processing efficiency and equipment scale. In the above-mentioned crushing nozzle facing type crusher, the remarkable effect of the nozzle facing can only be obtained when the particle size of the colliding powder is about 10 μm or more, and in the above object collision type crushing machine, the abrasion of the powder colliding wall surface , due to the wear, there is a problem in terms of durability as well as the problem of contamination of foreign matter.

Furthermore, the jet-o-mizer type crusher mentioned above is
Although this device has a structure that can be used as an industrial-scale device with a relatively large throughput, there is a problem that the particle size of the resulting pulverized powder is not very fine. Because this type of classification mechanism is not used, there is a problem in that it is difficult to avoid mixing of powders with large particle sizes, regardless of the mixing ratio.

(Object of the Invention) The present invention has been made from the above-mentioned viewpoints, and its purpose is to solve the various problems in the conventional jet stream type crusher as described above, and to provide excellent processing efficiency. In particular, it efficiently classifies pulverized fine powder with a particle size of about 10 μm or less.
An object of the present invention is to provide a crusher having a structure that allows for extraction.

Another object of the present invention is to provide a crusher that is simple in structure, compact, and has excellent operability.

(Summary of the Invention) The jet stream type crusher of the present invention, which has been made to achieve the above object, is characterized by an outer wall that partitions a flat, generally oval internal space; With the central bulkhead block placed approximately in the center of the interior space,
A circular cavity-type classification zone for swirling the powder is formed at one end in the long sleeve direction of the internal space, and a passage-like gas phase flow path along the inner surface of the outer wall is formed from the classification zone to the oval The shaped internal space is formed so as to go around the other end in the longitudinal direction, and the part on the other end in the long sleeve direction of the passage-like gas phase flow path is used as a pulverization zone, and a jet air flow for powder pulverization is applied to the part. The pulverizer is provided with a nozzle device that ejects water along the gas phase flow direction, and further provided with an outlet approximately in the center of the classification zone to lead out the pulverized fine powder to the outside by the gas phase flow. a gas phase flow path leading to the crushing zone, and a gas phase flow path leading from the crushing zone to the classification zone;
At each upstream position, an air blowing device for amplifying powder fluidity along the flow direction is arranged.

The reason why the present inventors developed the present invention is as follows.

In other words, in this type of jet-air flow mill that pulverizes powders that flow in a gas phase, the classification zone separates small powders from powders containing a mixture of large and small particles. To provide a good pulverizer that satisfies the desired requirements in each of two independent mechanical parts: taking out the powder, and pulverizing the powder efficiently with a large crushing force in the pulverizing zone. required above.

When this is applied to a specific pulverizer, it is important to provide sufficient fluidity to the powder in the classification zone to enhance the classification effect of the gas-phase fluidized powder. Furthermore, in the crushing zone, it can be said that a configuration is preferably adopted in which the fluidity of the powder is suppressed to increase the opportunity for crushing by the jet stream, and it is from this viewpoint that the above-mentioned present invention has been proposed. be.

Therefore, in the configuration of the present invention described above, the fluidity of powder in the classification zone configured in a powder swirl type is increased without being influenced by the crushing zone or having a negative effect on the crushing zone. In addition to the essential feature of the present invention that a means is provided, it is also adopted as a preferred embodiment that a flow resistance means for suppressing powder fluidity in the grinding zone is also provided. Examples of resistance means for suppressing the powder fluidity in the crushing zone include blowing an air flow in a direction perpendicular to the gas phase flow in the crushing zone, or providing a structural throttling mechanism to function as a weir. Often preferred.

In order to feed the powder to be processed into the pulverizer configured as described above, the feeding position and feeding direction can be determined so that the powder flows in an approximately oval shape in the gas phase. It is preferable that an air current blowing device provided at an upstream position of a gas phase flow path that flows the powder from the classification zone toward the crushing zone also serves as the powder blowing device.

In the present invention, the internal space containing each zone of one classification of powder is formed into a roughly elliptical shape for the purpose of isolating the mutual influence of these zones, but this does not mean in a strict sense. It does not require an oval shape.

(Example of the invention) The present invention will be described below based on embodiments shown in the drawings.

Fig. 1 is for explaining the outline of the configuration of a jet air flow type crusher according to an embodiment of the present invention. As shown in the figure, the internal space 1 is formed as a generally horizontal and flat elliptical space, and has a gas phase flow guide outer wall 5 that limits the outer contour of the elliptical space and forms a flow path for the powder. (hereinafter referred to as the outer wall 5), a partition bottom plate 13, and a lid 10, which are airtightly sealed from the outside. 1
1° 12 is a sealing ring that ensures the sealing.

Also, within this internal space 1, there is formed a central partition block 6 having the shape shown in the figure, which is used to separate the crushing zone 2 and the classification zone 3 and to form a suitable configuration for both zones. So, this central bulkhead block 6
However, in the crushing zone 2, the gas phase flow guide inner wall 60 formed opposite to the outer wall 5 provides a gas phase flow path 4b in the crushing zone for the powder flowing in the gas phase, and in the classification zone 3, , is provided so as to provide a swirling flow guide inner wall 61 for the present classification mechanism, which extracts fine powder from the central portion by swirling flow.

Also, between the crushing zone 2 and the classification zone 3 is the outer wall 5.
and a central partition block 6 to form a passage-shaped gas phase flow path 4a,
4c. That is, 4a forms a gas phase flow path from the classification zone 3 to the crushing zone 2,
4C constitutes a gas phase flow path from the above-mentioned crushing zone 2 to the classification zone 3.

Outside the internal space sealed from the outside as described above,
The internal space 1 includes a partition wall, a bottom plate 13. A compressed air chamber 7 is provided which is pressure-isolated by an outer wall 5 and a central partition block 6, and is also pressure-isolated from the outside by a pressure chamber casing 14.

This compressed air chamber 7 is connected to an external compressed air source (for example, a compressor, etc.) (not shown) via a compressed air introduction pipe 21 connected to a compressed air intake 20, and is also connected to a jet air flow ejection nozzle 50a, which will be described later. From ~50e, compressed air is blown into the internal space 1.

The compressed air chamber 7 is also connected to the compressed air chamber 8 in the central partition block through the through hole 9, and similarly to the above, the internal space 1 is compressed from a jet air jet nozzle 50f, which will be described later. It is designed to blow air.

The powder feeding mechanism in the pulverizer of this example is shown in Figure 1 (
a), as shown in more detail in FIGS. 2 and 5(a). That is, a powder jetting nozzle 4 whose outer end faces the compressed air chamber 7 and whose inner end faces the gas phase flow path 4a is located at a position continuous from the classification zone 3 to the gas phase flow path 4a.
0, and the upper part of the intermediate position of this powder jet nozzle 40 is connected to the lower end thin opening 41 of the powder supply hopper 42 attached to the upper part of the i body 10, and compressed air is supplied from the compressed air chamber 7 to the nozzle 40. When the powder is blown out into the internal space 1 through the internal passage, the ejector effect causes the powder to be blown out into the internal space 1 at the same time. Note that 43 is a diffuser fitted into a passage inside the nozzle 40.

By the nozzle 40, the powder from the hopper 42 is
As shown in FIG. 1(a), the gas is ejected along the flow direction of the gas phase into the gas phase flow path 4a. The airflow of the powder blowing at this time also has the effect of improving the classification performance of the powder swirling in the classification zone 3.

Note that 15 is a leg that supports the pressure chamber casing 14;
Each of the above-mentioned components except for the legs 15 is generally constructed using a mirror-finished material such as stainless steel. Ceramics are also used for highly abrasive powders.

FIG. 4 schematically shows an outline of the flow of powder that takes place in the internal space 1, and the specific configurations of the crushing zone 2 and classification zone 3 shown in the same figure will be explained below. .

The configuration of the crushing zone 2 in this example is as shown in FIG. 1(a). That is, in the gas phase flow path 4b, which is a passage for the powder carrier gas and is formed in an arc shape, there is a path approximately approximated to the flow direction of the powder flowing together with the carrier gas.
First to fourth jet stream ejection nozzles ζOI+1 to F+nAM for blowing the jet stream are provided on the plate wall 6, and each of these nozzles 50a to 50d
The outer end faces the compressed air chamber 7 and the inner end faces the gas phase flow path 4b or 4C, and the compressed air is directed from the compressed air chamber 7 through the inside of the nozzle to the gas phase flow path 4b or 4C. It is installed to blow into 4C.

A diffuser is inserted into these nozzles 5Qa to 50d in the same way as the powder jetting nozzle 40, and the jetting speed of the airflow is adjusted to blow out the flowing powder in the above-mentioned direction. Grinding is preferably performed by rolling the powder and colliding with each other. Figure 5 (b
) shows the entrainment and collision of powder by this jet stream.

In this example, in addition to the first to fourth jet stream ejection nolls 50a to 50d, second and third nolls 50a to 50d are provided.
Fifth and sixth jet streams are disposed opposite to each other across the gas phase flow path 4b between 0b and 50c, and the ejection direction of the jet stream is set in a direction substantially perpendicular to the gas phase flow path 4b. Ejection nozzles 50e and 50f are provided. These fifth and sixth jet stream ejection nols 50e, 5
The structure of 0f is substantially the same as the structure of the other nozzles described above, except that the air jet direction with respect to the gas phase flow path 4b is different, and compressed air from the compressed air chamber 7 is blown into the gas phase flow path 4b. It's starting to look like this.

The fifth and sixth jet stream ejection nols 50e,
50f generates a type of weir (hereinafter referred to as an airflow weir) in the gas phase flow path 4b which is the crushing zone by ejecting airflow, and suppresses the fluidity of the powder.
The residence time of the powder at the upstream position (nolds 50a, 50b side) is longer than that in the case where there is no airflow ejected from the nols 50a, 50b. , to increase the chance of collision between powder particles and achieve improvement in grinding efficiency.

On the downstream side of the airflow weir formed by the airflow jetting from the jet airflow jetting nols 50e and 50f,
The air jet from c and 50d gives the powder an opportunity to be crushed by the jet air, and in particular, the jet jet nozzle 50d amplifies the fluidity of the powder, which has been suppressed by the air weir in the crushing zone, and classifies the powder. It is designed to provide favorable classification performance in the zone.

The configuration of the classification zone 3 in this example is such that the powder introduced into the internal space 1 and guided to the classification zone 3 via the crushing zone 2 is swirled by the outer wall 5 and the swirling flow guide inner wall 61. From the fine powder outlet 30 of the lid body 10 formed at the center of the classification zone 3, the air flows out from the powder outlet 30 to the outside due to positive pressure inside the space.
It is provided to lead out the fine powder to the outside.

Reference numeral 31 denotes a fine powder extraction pipe connected to an airflow classifier which is normally connected at a later stage, and is connected and fixed to the lid 10 via a fine powder extraction pipe connecting flange 32.

The principle of classifying and extracting using the above-mentioned swirling flow method is that fine powder of small particle size among the crushed powder is transported by the conveying force of the gas phase flow.
This is a system that separates and takes out the powder in relation to the centrifugal force that acts on the powder.In particular, in this example, when applying such a classification and take-out mechanism to a pulverizer, we have developed a system for the pulverizer to increase the classification efficiency. It is characterized by conveniently matching the configuration with the principle.

That is, in the crusher of this example, in the internal space 1 forming an oval gas phase flow path, the upstream end positions of the gas phase flow paths 4a and 4c, which form the straight portion of the oval shape, are Nozzles (powder jet nozzle 40 and fourth jet air flow jet nozzle 50d) that jet airflow so as to increase the gas phase fluidity of the powder are arranged, thereby causing the powder to flow on the inner surface of the outer wall 5. This allows for suitable fluidity through classification along the length.

According to this configuration, for powder with a relatively large particle size (coarse powder), the centrifugal force accompanying the gas phase flow is greater than the gas phase flow toward the center in the classification zone 3. As a result of this action, the large particle size powder is transferred to the grinding zone 2 again.
However, for small-sized powders that have been sufficiently pulverized by crushing, the conveying force due to the flow of the gas phase toward the center of the classification zone 3 overcomes the centrifugal force described above. The fine powder is then taken out from the fine powder outlet 30.

FIG. 5(c) shows a state in which this fine powder is taken out at the same time as it flows out.

An example of testing using a jet stream type crusher having the above configuration will be shown.

Example In this test, graphite powder with a 50% average diameter D 5o-w of 37.6 μm was used as the raw material to be crushed.
．． By introducing 4 kg/0m2 of compressed air,
The total air volume was 1.48 m37 w1n (nozzle diameter 2 mm, air volume per nozzle 0.2 to 0.288 m37 w1n). However, the test was conducted with the nozzles 50e and 50f closed.

The amount of powder processed was between 2.6 kg/h and 25 kg/h.

The results are shown in FIG. 6 by line A.

Comparative Example A test was carried out by putting the same powder as in the above example into a jet-o-mizer mill type 0202 apparatus, and the results are shown by line B in FIG.

The pulverizer used in this comparative example did not have a gas-phase swirling flow type classification mechanism, but had a fine powder outlet opening in a part of the inside of the passage.

As is clear from the results shown in FIG. 6, it can be seen that the powder classification efficiency is improved in the pulverizer having the separation i& mechanism of the present invention.

(Effects of the Invention) As described above, the jet stream type pulverizer of the present invention solves various problems in the conventional jet stream type pulverizer, and can particularly crush powders of relatively small particle size. It also has excellent processing efficiency and can be used on an industrial scale, especially when producing pulverized powder with a particle size of about 10 μm or less on an industrial scale. There is an effect that fine powder with a constant particle size can be suitably obtained with almost no contamination of powder with a uniform diameter.

Furthermore, the crusher according to the present invention has a simple and small structure, and
It also has the advantage of being easy to use, and its usefulness is extremely impressive.

[Brief explanation of the drawing]

FIG. 1(a) is a partially sectional plan view showing an outline of the configuration of a jet stream type crusher according to the present invention, and FIG.
) is a longitudinal sectional front view of the device, Figure 2 is a front view showing the exterior of the equipment, Figure 3 is a plan view showing the exterior of the equipment, and Figure 4 outlines the flow of powder in the equipment. Figures 5 (a) to (c) are partial cross-sectional views showing the flow of powder in parts of the same device, and Figure 6 is a characteristic diagram showing the test results conducted using the same device. be. 1: Gas phase flow internal space 2: Grinding zone 3: Classification zone 4a, 4b, 4c: Gas phase flow path 5: Gas phase flow guide outer wall 6: Central partition block 7: Compressed air chamber 8: Compressed air in central partition block Chamber 9: Through hole 10: Lid body 11: Seal ring 12: Seal ring 13: Partition bottom plate 14: Pressure chamber casing 15: Legs 20: Compressed air intake 21: Compressed air introduction pipe 30: Fine powder outlet 31: Fine powder outlet Pipe 32: Fine powder extraction pipe connection flange 40; Powder jet nozzle 41: Lower end thin opening 42: Powder supply hole 43
: Diff users 50a to 50f: Jet stream jetting nozzle 60: Gas phase flow guide inner wall 61; Swirling flow guide inner wall Figure 2 Figure 3 Cultivating the product (0% ne' 1 1 5 ○ 5 oiyn procedural amendment document Patent Office Other than the Commissioner; +l, i:j: Mr. Hiroshi 1, Indication of the case 1986 Patent Registration No. 2) Nagaku 7 No. 3, Person making the amendment Relationship to the case Application Address 2-6 Marunouchi, Chiyoda-ku, Tokyo No. 2 Marunouchi to Shigesu Building 3 (Capital) 8, Contents of amendment as shown in the attached document, Figure 5 (α)

Claims (2)

[Claims] (1) Powder is swirled at one end in the longitudinal direction of the internal space by an outer wall that partitions a flat, roughly elliptical internal space and a central partition block placed approximately in the center of the internal space. A circular cavity-type classification zone is formed in which the fluid flows, and a passage-like gas phase flow path is formed along the inner surface of the outer wall so as to go around from the classification zone to the other end in the longitudinal direction of the oval internal space. At the same time, a part on the other end side in the longitudinal direction of the passage-like gas phase flow path is provided as a crushing zone, and a nozzle device is provided in the part to eject a jet air stream for powder crushing along the gas phase flow direction, Furthermore, the pulverizer is provided with a take-out port approximately in the center of the classification zone to lead out the pulverized fine powder to the outside by gas-phase flow, and a gas-phase flow path leading from the classification zone to the pulverization zone, and a flow path from the pulverization zone to the classification zone. A jet airflow type crusher characterized in that an airflow blowing device for amplifying powder fluidity along the flow direction is arranged at each upstream position of the gas phase flow path leading to the zone. (2) An air blowing device disposed upstream of the gas phase flow path from the classification zone to the crushing zone doubles as a powder blowing device for blowing powder to be crushed into the internal space. A jet stream crusher according to claim (1), characterized in that: