JP2645870B2 - Wet vertical crusher - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wet vertical pulverizer for introducing an object to be pulverized together with a liquid into a casing and pulverizing the same.

[Prior Art] Conventionally, ball mills and rod mills are known as wet mills. A grinding mill (ball stirring mill) is also known. However, such conventional wet crushers have problems such as poor crushing efficiency and difficulty in increasing the size.

On the other hand, as a dry pulverizer, a vertical pulverizer that can be efficiently and large-sized is known. This vertical pulverizer performs pulverization by pressing a roller on a rotary table and rotating the rotary table so that the pulverized material is dried and transported by hot gas introduced into the pulverizer from the outer periphery of the table. It is composed.

[Problems to be Solved by the Invention] As described above, in a conventional wet pulverizer, for example, a ball mill or a rod mill uses a plurality of balls to impact or friction-pulverize a material by centrifugal force or dropping force. Since the force of one ball is small and the whole amount of the ball does not contribute to the grinding, the grinding efficiency is poor. Further, since the ball is used as a grinding medium, it is not suitable for high-concentration grinding, that is, high-viscosity grinding.

Also, if a conventional dry type vertical pulverizer is used as it is for wet pulverization, the rate of material biting into the rollers is poor, a large amount of raw material-sized material is discharged from the table, and it is necessary to supply these particles to the rollers again. However, the pulverization efficiency was poor, and it was not suitable for fine pulverization.

[Means for Solving the Problems] A wet vertical crusher according to the present invention comprises a rotating table, a plurality of crushing rollers disposed on the rotating table, and a plurality of crushing rollers in a casing. A wet vertical pulverizer, which is freely pivotally supported and includes urging means for pressing the pulverizing roller against the upper surface of the rotary table via a connecting member, and introducing the pulverized object and the liquid into the casing,
A rotating cylinder having a classification cone having a frusto-conical shape standing upright on the upper surface of the rotary table and having a truncated cone-shaped classification cone at an upper end, a rectifying inner cylinder hanging down from the connecting member into the rotating cylinder, and
It is provided with a discharge port for discharging the slurry overflowing the rotary cylinder to the outside of the casing.

Second, a plurality of crushing rollers are rotatably supported on a column vertically hanging on the center axis of the vertical crusher, and the crushing rollers are connected via a connecting member connected to the column. Was mounted outside the casing by pressing the cylinder against the upper surface of the rotary table.

Third, the shape of the rotary cylinder is constituted by a truncated inverted conical portion, a cylindrical portion, and a truncated conical portion from upward to downward.

Fourth, the rotary cylinder is configured to have a truncated inverted conical portion below and a truncated conical portion above.

Fifth, a return cone having a concentric cylinder or a truncated inverted conical shape is disposed inside the rotary cylinder along the circumference of the lower portion of the rotary cylinder.

Sixth, a plurality of rectifying blades are radially provided so as to protrude from the return cone along the lower inner surface of the return cone.

[Operation] In the wet vertical pulverizer of the present invention, the object to be pulverized introduced into the casing together with the liquid includes a rotating table,
Pulverization is performed by being pinched between the rotation roller and the driven and rotated pulverizing roller. The crushed material having a predetermined crushed particle diameter is formed into a slurry containing a liquid, overflows from the upper end surface of a rotary cylinder erected on the outer periphery of the rotary table, and is discharged out of the machine through a discharge port. .

Embodiment Hereinafter, an embodiment will be described in detail with reference to the drawings. 1 to 4 show a wet type vertical pulverizer according to an embodiment of the present invention, wherein FIG. 1 (a) is an overall vertical sectional view, and FIG. 1 (b) is FIG. 1 (a) I-. FIG. 2 is a plan view seen from I, FIG. 2 is an enlarged sectional view of a main part, and FIG. 3 is an enlarged sectional view of a main part showing another embodiment of the rotary cylinder. FIG. 4 is an explanatory view of a flow model. FIG. 5 is a viscosity distribution diagram showing an example of the present invention in comparison with a conventional example.

A rotary table 2 is installed at the center of the inside of the casing 1 so as to rotate around a vertical axis by a motor (not shown) via a variable speed reducer 4. On the other hand, a plurality (3 in this embodiment)
Of the crushing rollers 3 are rotatably mounted on crushing roller bearings 3a. The pulverizing roller bearing 3a is vertically reciprocally connected by a connecting rod 11 connected to three sets of hydraulic cylinders 12 via a column 9 extending vertically upward and a connecting member 10 penetrating the casing 1. Therefore, it goes without saying that the casing through-hole of the connecting member 10 is an elongated hole. Further, the rotary cylinder is fixed to the rotary table 2 by tightening means such as bolts over substantially the entire outer peripheral end of the rotary table 2.
Stand on top. The rotary cylinder 5 may be of a straight cylindrical shape, or as shown in FIGS. 1 and 2, three parts of a truncated inverted conical part, a cylindrical part, and a truncated conical part are joined upward from below. They may be configured together. Further, as shown in FIG. 3, a truncated inverted conical part and a truncated conical part may be used. However, a classification cone 6 having a frusto-conical shape is provided at the upper end of the rotary cylinder in any shape. On the other hand, a cylindrical rectifying cylinder 7 is provided so as to be suspended so as to enter the inside of the rotary cylinder 5 from the connecting member 10 to the height of the upper half of the rotary cylinder 5. A plurality of supports concentric with the truncated inverted conical portion 5a at the lower end of the rotary cylinder are bent downward from the casing 1 with a return cone 8 formed in a truncated conical shape about 10 mm apart therefrom. 8a. Also,
At the lower end of the return cone 8, a plurality of rectifying blades 8b are provided so as to project radially. When the rotating cylinder is a straight cylinder and the lower end is not a truncated inverted cone but a cylinder, the return cone 8 is also a concentric cylinder separated by about 10 mm (about 20 mm in diameter). Inside the casing 1, near the side or lower side of the turntable 1, a classification cone 6 at the upper end of the rotary cylinder 5 is provided.
A flow path and a discharge port 14 are provided for collecting the slurry from which the water has flowed and discharging the slurry to the outside of the casing. Reference numeral 15 denotes a supply chute for supplying an object to be ground and a liquid, which is fixedly supported on the casing 1.

The operation and function of the wet vertical crusher of the present invention configured as described above will be described.

First, the electric motor is started to rotate the rotary table 2 via the variable speed reducer 4, and at the same time, a mixture of a material to be ground and a liquid (hereinafter referred to as “raw material”) is supplied from the supply chute 15. Further, pressure oil is supplied to a hydraulic cylinder 12 supported by a pin 13 on a stand 13 outside the casing, and the crushing roller 3 is pressed against the upper surface of the rotary table with a predetermined force via the connecting rod 11, the connecting member 10 and the column 9. This pressing force can be arbitrarily changed in consideration of the pulverizing properties, the processing amount, and the product particle size after pulverization.

The behavior of the raw material in the above-described steady operation state will be described below.

The raw material of the new feed, which is supplied to the vicinity of the center of the crusher by the supply chute 15, is successively pressed between the crushing roller 3 and the rotary table 2, undergoes compression and grinding action, and is subjected to centrifugal action by rotation of the rotary table 2. As a result, the powder flows spirally from the center of the crusher to the outer periphery.

This will be described with reference to an explanatory view of the flow model shown in FIG. 4. New feed F is successively subjected to a pulverizing action, and then a passage formed between the inverted cone 5a at the lower end of the rotary cylinder and the return cone 8 is formed. (Arrow A), the coarse particles having a relatively large particle size are immediately guided again between the grinding roller and the rotary table through the path shown by the arrow C and pulverized. On the other hand, the medium particles and fine particles excluding these coarse particles rise as they are along the inner circumferential circle of the rotating cylinder, and eventually reach the inner circumferential surface of the classification cone 6. Here, the particles suspended in the liquid are uniformly subjected to centrifugal force, but the centrifugal force is proportional to the mass, that is, the cube of the particle diameter (D) (D ³ ), but this is impeded. Since the liquid resistance is proportional to the cross-sectional area of the particles, that is, the square of the particle diameter (D ² ), the larger the particles, the more the particles are distributed on the inner peripheral wall surface of the classification cone. Then, as shown in FIG. 4, the medium particles contacting the inner peripheral wall receive a horizontal centrifugal force H due to fluid rotation, while the component R perpendicular to the inner wall receives an equal force R in the opposite direction from the inner wall. After being offset, it eventually descends by receiving a downward force D along the inner wall surface shown in the figure, and then returns to the grinding roller again on the path indicated by arrow C on the same path as the coarse particles.

In this way, the coarse particles and the medium particles gradually change into fine particles by re-grinding, but the fine particles do not settle down in the vicinity of the classification cone because the downward flow action indicated by arrow D is weaker than that of the coarse particles and the medium particles. Then, as the volume of the rotary cylinder 5 increases due to the raw material of the new feed which is sequentially fed, the fine particles flow out from the upper end of the classification cone 6 as a slurry, so that only the fine particles are discharged out of the casing.

The function of the flow regulating cylinder 7 in the above-described series of particle behaviors (flow and classification) will be described. The raw material (the liquid containing the material to be pulverized) in the rotary cylinder behaves in such a manner that the rotation in the rotary table is combined with the above-described vertical flow while accompanied by a clockwise swirling flow by the rotation of the rotary table. . However, the lower end circumferential surface of the crushing roller moves in the direction of the rotary table (for example, clockwise), while the upper end surface of the crushing roller rotates in the counterclockwise direction opposite to this direction. It acts in the opposite direction to the swirling flow of the liquid to stir the liquid. Therefore, the classifying action near the classifying cone 6 described in FIG. 4 is significantly inhibited. In order to prevent this, the flow regulating cylinder 7 is hung between the grinding roller 3 and the classification cone 6, and the reverse rotation, that is, the effect of stirring is shut out.

In addition, the return cone 8 forms a passage for guiding the crushed particles to the classification cone 6, and at the same time, the crushed material adheres to the inner surface of the truncated inverted conical portion 5 a at the lower end of the rotary cylinder 5 in a cake form. Play a role in preventing That is, by providing the return cone 8 stationary with respect to the rotating truncated inverted conical portion 5a, it plays the role of a scraper for scraping off the cake adhering. The inner inclined surface also serves as a guide plate for returning coarse particles as described above. A plurality of rectifying blades 8b provided below the return cone 8 so as to protrude from the return cone 8 are for suppressing the flow of the swirling flow of the slurry and promoting the return of the coarse particles indicated by the arrow C.
Although the rectifying blade 8b is installed at an intermediate position between adjacent crushing rollers as shown in FIG. 1B, it can be installed anywhere as long as it does not interfere with the crushing roller. The product discharged from the pulverizer according to the present invention may be subjected to secondary classification with a classifier installed outside the pulverizer, and coarse particles may be recycled to obtain ultrafine powder particles.

Limestone (raw material particle size: 20 mm or less) as a material to be ground by a wet vertical grinder according to the present embodiment, and fine particles obtained by further pulverizing the same by a wet vertical grinder with a classifier. FIG. 5 shows a comparison diagram of the distribution.
As can be seen from the figure, the embodiment of the present invention has a much smaller average particle size and a sharper particle size distribution than the conventional example, and can carry out ultrafine grinding and uniform grinding.

[Effects of the Invention] According to the present invention, since the pulverization is performed by a wet method and using a roller, the pulverization is mainly performed by grinding under a high pressure, the agglomeration does not easily occur after the pulverization, and the liquid in the pulverizer has a small size. Because of the excellent classifying effect of the particles, it is possible to obtain an excellent product having ultra-fine particles and uniform particles having a narrow particle size distribution.

In addition to conventional ceramic raw materials (limestone, cement raw materials, coal, dolomite, etc.), new materials such as ceramics, pigments, and chemicals can achieve ultra-fine grinding of submicron or less, which has been difficult in the past. it can.

It can also be used for the treatment of lime milk and various ores used for flue gas desulfurization and water treatment. In addition, even in high-concentration (high-viscosity) mixed grinding, mixing and grinding can be performed without adhering to the container, and mixed grinding such as CWS (cold water slurry) and COM (cold oil mixture) can be easily performed. It is.

In addition, since the wet grinding is performed and the roller is crushed, the power consumption of the crusher is about 50% or less as compared with a conventional crusher such as a ball stirring mill, so that the power consumption can be greatly reduced.

[Brief description of the drawings]

1 to 4 show an embodiment according to the present invention. FIG. 1 (a) is an overall vertical sectional view, and FIG. 1 (b) is FIG. 1 (a) I.
2 is an enlarged sectional view of a main part, FIG. 3 is an enlarged cross-sectional view of a main part showing another embodiment of the rotary cylinder, and FIG. 4 is an explanatory view of a flow model. FIG. 5 is a particle size distribution diagram in an example of the present invention and a conventional example. DESCRIPTION OF SYMBOLS 1 ... Casing, 2 ... Rotary table, 3 ... Grinding roller, 3a ... Grinding roller bearing, 4 ... Reduction gear, 5 ... Rotating cylinder, 6 ... Classification cone, 7 ... Rectifying cylinder, 8 ... ... Return cone, 8a ... Support, 8b ... Rectifier blade, 9 ... Column, 10 ... Connecting member, 11 ... Connecting rod, 12 ... Hydraulic cylinder, 13 ... Stand, 14 ... Discharge port, 15 ... Supply chute.

Claims (6)

(57) [Claims] 1. A rotary table, a plurality of crushing rollers disposed on the rotary table, and a plurality of crushing rollers rotatably supported in a casing. The crushing roller is connected via a connecting member. A pressurizing means for bringing the object to be crushed and the liquid into the casing. A rotating cylinder having a classifying cone having a shape, a rectifying inner cylinder hanging down from the connecting member into the rotating cylinder, and a discharge port for discharging a slurry overflowing the rotating cylinder to the outside of the casing. Wet vertical pulverizer characterized by the following. 2. A plurality of crushing rollers are rotatably supported on a column vertically hanging down on a central axis of a vertical crusher,
2. The wet vertical crusher according to claim 1, wherein a hydraulic cylinder for pressing the crushing roller against the upper surface of the rotary table via a connecting member connected to the column is provided outside the casing. 3. A wet type vertical pulverizer wherein the rotary cylinder of claim 1 is provided with a truncated inverted conical portion, a cylindrical portion, and a truncated conical portion arranged upward from below. 4. The rotary cylinder according to claim 1, wherein the rotating cylinder is truncated inverted conical part downward,
A wet vertical pulverizer formed with a truncated conical section disposed above. 5. The wet type vertical crusher according to claim 1, wherein a return cone having a concentric cylindrical shape or a truncated inverted conical shape is disposed inside the rotary cylinder along the circumference of the lower portion of the rotary cylinder. 6. The wet type vertical crusher according to claim 5, wherein a plurality of rectifying blades are provided radially protruding from the return cone along the inner surface of the lower part of the return cone.