JPH0574681U - Multi-stage classifier - Google Patents

Abstract

(57) [Summary] [Purpose] To enable large-scale and accurate multi-stage classification of raw materials with a wide particle size distribution. [Composition] A mixed airflow 5 is introduced from the outer periphery of the rotating classification blade 4, and the fine powder 6 and the classification blade 4 passing through the classification blade 4 are introduced.
The rotary classifier 1 is designed to classify into the coarse powder 7 that falls without passing through, and the air conduit 9 connected to the rotary classifier 1 is provided, with respect to the air flow 10 in the air conduit 9. A raw material supply port 13 is provided in the middle of the air conduit 9 so that the raw material 14 is dropped and supplied in the intersecting direction, and coarse particle separation hoppers 16 and 17 are provided below the raw material supply port 13 in the air conduit 9. And a gravity classifier 26.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a multi-stage classifier capable of accurately classifying raw materials in multiple stages.

[0002]

[Prior Art]

 When classifying raw materials having a wide particle size distribution into desired particle sizes, it has been customary in the past to use a mechanical multi-stage sieve (Mogensen multi-stage sieve). This mechanical multi-stage sieve is designed to perform classification by vibrating the sieve mesh using a metal coil and supplying the raw material onto the sieve mesh. Therefore, a plurality of meshes corresponding to the particle size to be classified are selected. It has a sieve mesh.

[0003]

[Problems to be solved by the device]

 However, in the conventional mechanical multi-stage sieve as described above, the mesh of the sieve is severe and the maintenance is difficult, and the mesh of the sieve is apt to be clogged, so that it is not suitable for the classification of a large volume. Further, there was a problem that there was a limit to the minimum particle size that could be classified due to mechanical restrictions on the size of the sieve mesh.

In addition, a rotary classifier that introduces a mixed air flow of raw materials from the outer circumference of a rotating classifying blade to classify it into fine powder that passes through the classifying blade and coarse powder that falls without passing through the classifying blade is provided. Although it has been implemented, it is difficult to classify the particle size in three or more steps, and the rotary classifier is suitable for classifying fine particles such as powder, but coarse particles are used. When classifying a raw material having a wide particle size distribution such as that containing coarse particles into fine powder due to splashing due to collision of particles, there is a problem that the classification accuracy decreases.

The present invention has been made in view of the above conventional problems, and an object of the present invention is to provide a multi-stage classifier capable of classifying a large amount of a raw material having a wide particle size distribution with high precision in multiple stages. To do.

[0006]

[Means for Solving the Problems]

 The present invention is directed to a rotary classifier in which a mixed airflow is introduced from the outer circumference of a rotating classifying blade to classify it into fine powder passing through the classifying blade and coarse powder falling without passing through the classifying blade, and the rotary classifier. An air conduit connected to the classifier is provided, and a raw material supply port is provided on the upper side of the air conduit so that the raw material drops and is supplied in a direction intersecting with the air flow in the air conduit, and the raw material supply in the air conduit is performed. The multi-stage classifier and the air duct of the gravity classifier, which are equipped with a gravity classifier equipped with a coarse-grain separation hopper at a position below the mouth, are rotated at the required downward gradient angle. The present invention relates to a multi-stage classifier, which is characterized in that it is connected to the outer circumference of a classifying blade of a type classifier.

[0007]

[Action]

 In the present invention, when the raw material is supplied from the raw material supply port of the gravity classifier so as to intersect with the air flow in the air conduit, the fine powder and coarse powder in the supplied raw material ride on the air flow in the air conduit to the downstream side. Only the coarse particles that are carried away to the side and do not ride on the air flow are dropped into the coarse particle separation hopper by gravity and separated.

A mixed air stream of fine powder and coarse powder from which coarse particles have been separated is introduced tangentially from the outer periphery into the classification blade of a rotary classifier from an air conduit and passes through the classification blade without passing through the fine powder and the classification blade. It is accurately classified into the falling coarse powder.

[0009]

【Example】

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

FIG. 1 and FIG. 2 show an example of the multi-stage classifier of the present invention, in which fine powder as a product from raw materials such as cement raw material and a ball mill (secondary pulverizer) are used again. It is suitable for the case where it is necessary to classify coarse particles that need to be crushed and coarse particles that need to be crushed again by a crusher for exclusive use of coarse particles (primary crusher) in multiple stages and with high precision.

That is, 1 is a rotary classifier equipped with a classifying blade 4 which is rotated around a vertical axis by a drive motor 2 via a speed reducer 3 and a fixed rectifying blade 4 ′. The mixed air flow 5 is introduced from the outer circumference of the rectifying blade 4 and the rectifying blade 4 ', and is classified into fine powder 6 passing through the classifying blade 4 and coarse powder 7 falling without passing through the classifying blade 4.

A gravitational classifier 26 is connected to the rotary classifier 1.

That is, the other end of the air conduit 9 having an air inlet 8 at one end and a required downward slope angle α so that coarse powder 7 does not accumulate at the bottom is classified by the rotary classifier 1. It is tangentially connected to the outer circumference of the blade 4. At the rear position of the air introduction port 8 of the air conduit 9, there is provided a rectifying plate 11 for rectifying the air flow 10 in the air conduit 9 so as to be uniformly stabilized, and the air conduit 9 is tangentially connected to the rotary member. An inclined surface 12 having a required angle β is formed on the bottom of the type classifier 1 so that the coarse powder 7 is not deposited.

Further, a raw material supply port 13 is formed on the upper side in the middle of the air conduit 9, and a raw material 14 from the raw material supply port 13 falls in a direction intersecting with the air flow 10 in the air conduit 9. The raw material dispersion plate 15 is provided so as to be supplied. The raw material dispersion plate 15 is provided so that an angle γ formed between the air introduction port 8 side of the air conduit 9 and the raw material dispersion plate 15 is approximately 90 degrees or 90 degrees or more.

Further, a coarse grain separation hopper 16 is provided below the raw material supply port 13 in the air flow rectifying conduit 9. In the case shown in the figure, another coarse particle separating hopper 17 is provided on the rotary classifier 1 side of the coarse particle separating hopper 16 so that two kinds of coarse particles 18 having different particle sizes can be separated. Further, an adjusting plate 19 is provided between the two coarse-grain separating hoppers 16 and 17 so that the grain size for separation can be changed. The adjusting plate 19 may be fixed or may be omitted.

A coarse powder recovery hopper 20 is provided below the inclined surface 12 of the rotary classifier 1, and a fine powder collector 21 and a suction fan are provided above the inside of the classifying blade 4. A fine powder collector 23 composed of 22 is connected via a suction pipe 24. Reference numeral 25 in the drawing denotes an air lock feeder provided in the raw material supply port 13, the coarse particle separating hoppers 16 and 17, and the coarse powder collecting hopper 20.

Next, the operation will be described.

When the suction fan 22 of the fine powder collecting device 23 is driven, air is sucked from the air introduction port 8 of the air conduit 9 via the rotary classifier 1, and a stable air flow 10 is supplied into the air conduit 9. Is formed.

When the raw material 14 is supplied from the raw material supply port 13 of the gravity type classifier 26, the raw material 14 is supplied by the angle γ of the raw material dispersion plate 15 so as to intersect the air flow 10 in the air conduit 9, and the raw material 14 is supplied. The fine powder and coarse powder in 14 are carried on the air flow 10 in the air conduit 9 and carried away to the downstream side, and only the coarse particles 18 having a large weight that cannot be carried on the air flow 10 are transferred to the coarse particle separation hopper 16 by gravity. It is dropped, separated, and taken out to the outside via the airlock feeder 25. The coarse particles 18 having a relatively small particle size are separated by the coarse particle separating hopper 17 on the downstream side. In the case shown in the figure, the coarse particles 18 having different particle sizes can be separated by the two coarse particle separating hoppers 16 and 17, and the angle of the adjusting plate 19 provided between the two coarse particle separating hoppers 16 and 17 can be adjusted. By changing it, it is possible to control the particle size to be separated.

The mixed air flow 5 of fine powder and coarse powder from which the coarse particles 18 are separated is introduced from the air conduit 9 to the outer periphery of the classification blade 4 of the rotary classifier 1 in the tangential direction, and passes through the classification blade 4 and the fine powder 6 The fine powder 6 that has been accurately classified into the coarse powder 7 that does not pass through the classification blade 4 and has passed through the classification blade 4 is recovered by the fine powder collector 21 of the fine powder collecting device 23 and repelled by the classification blade 4. The coarse powder 7 that cannot pass through the inclined surface 12 falls into the coarse powder collecting hopper 20 and is taken out through the air lock feeder 25.

As described above, since the coarse particles 18 are separated by the gravity difference by the air flow 10 flowing through the air conduit 9, first, the coarse particles 18 can be stably and accurately separated. Subsequently, since only the fine powder 6 and the coarse powder 7 from which the coarse particles 18 are separated are guided to the rotary classifier 1 which has a small flow rate but is excellent in classification, the overall accuracy is high. Since the classification can be performed and the classification is performed using an apparatus that exhibits an excellent classification function depending on the particle size, the processing capacity of the apparatus can be increased.

The present invention is not limited to the above-mentioned embodiment, and the rotary classifier and the gravity classifier may be connected horizontally, or connected by interposing a connecting pipe between them. It is also possible to change the installation position of the raw material supply port, the installation position and number of the coarse grain separation hopper, the inclination angle of the air conduit and the raw material dispersion plate, etc., and other points not departing from the gist of the present proposal. It goes without saying that various changes can be made within the range.

[0023]

[Effect of the device]

 According to the multi-stage classifier of the present invention, the raw material is supplied into the air flow to first separate the coarse particles by the difference in gravity, and then only the fine particles and the coarse particles from which the coarse particles are separated are guided to the rotary classifier. Since it classifies the material into fine powder and coarse powder, the raw material can be classified in stages by a device that exhibits an excellent classification function according to the particle size, enabling highly accurate multistage classification and The excellent effect that the classification ability of the device can be increased can be obtained.

[Brief description of drawings]

FIG. 1 is a partially cut front view showing an embodiment of the present invention.

FIG. 2 is a plan view of FIG.

[Explanation of symbols]

 1 rotary classifier 4 classifying blade 5 mixed air flow 6 fine powder 7 coarse powder 9 air conduit 10 air flow 13 raw material supply port 14 raw material 16 coarse particle separation hopper 17 coarse particle separation hopper 26 gravity classifier α angle of descending gradient

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoji Sasahara 3-2-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries, Ltd. Toyosu General Office (72) Inventor Shingo Mukai 3-2 Toyosu, Koto-ku, Tokyo No. 16 Ishikawajima Harima Heavy Industries Co., Ltd. Toyosu General Office (72) Inventor Nobuya Hatta 3-2-16 Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Toyosu General Office

Claims (2)

[Scope of utility model registration request] 1. A rotary classifier in which a mixed air stream is introduced from the outer periphery of a rotating classifying blade to classify fine powder passing through the classifying blade and coarse powder falling without passing through the classifying blade, and the rotary classifier. An air conduit connected to the classifier is provided, and a raw material supply port is provided in the middle of the air conduit so as to drop and supply the raw material in a direction intersecting the air flow in the air conduit, and the raw material supply in the air conduit. A multi-stage classifier characterized by comprising a gravity type classifier having a coarse-grain separating hopper at a position below the mouth. 2. The multi-stage classifier according to claim 1, wherein the air pipe of the gravity classifier is connected to the outer periphery of the classifying blades of the rotary classifier with a required downward slope angle.