JPS62258757A - Vertical crusher - Google Patents

Abstract

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

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a vertical pulverizer that pulverizes cement raw materials, coal, chemicals, etc. through cooperation between a rotating table and pulverizing rollers.

[Prior Art] Vertical pulverizers equipped with a rotary table and rollers are widely used as a type of pulverizer for finely pulverizing powders such as cement raw materials, coal, and chemicals. This type of crusher has a disc-shaped rotary table that is driven by a motor with a reducer and rotates at low speed in the lower part of a cylindrical casing, and a hydraulic pressure etc. that is installed at the part that equally divides the outer periphery of the -L surface in the circumferential direction. It is equipped with a plurality of rollers that are pressed together and rotated as a result.

In this vertical crusher, powder as a raw material is supplied to the center of the rotary table through a supply pipe.

As the table rotates, the table receives a centrifugal force in the radial direction, and when it slides on the table, it receives a rotational force from the table, and as it slides between itself and the table, it rotates a little faster than the table rotation speed.

The above two forces, that is, the forces in the radial direction and the force in the rotational direction are combined, and the powder moves to the outer periphery of the rotary table while drawing a spiral trajectory on the table. Since the roller is in pressure contact with this outer periphery and is rotating, the particles with spiral lines enter from a direction that forms an angle with the direction of the roller between the roller and the rotary table and are bitten. Smash.

On the other hand, hot air is guided to the base of the casing by a duct, and as this hot air blows up from the annular space between the outer circumferential surface of the rotary table and the inner circumferential surface of the casing, the fine powder is dried and removed from the casing. The air rises inside the air and is discharged as a mixture with hot air through the outlet and sent to the next process.

By the way, if the material to be crushed supplied to the crusher is subjected to the crushing action by the crushing rollers only once, it will not be possible to crush it to the fine powder particle size required by this crusher, and the center of the rotary table will not be able to be crushed. Not all of the fallen objects to be crushed are bitten by the crushing rollers, so even if the powder and granules that reach the outer edge of the rotary table rise up on the hot air current blowing from the annular space in section 110. By the time the particles reach the separator installed at the top of the crusher, depending on their particle size, they may fall down or be classified and rejected by the separator before being returned to the rotary table.

In this way, the material to be crushed that is constantly fed into the crusher rises once from the rotary table to the separator, or rises from the rotary table to the separator until it reaches the desired fine powder particle size that will become the final product and flows out of the crusher. The powder is gradually crushed by falling from the middle of the separator many times until it reaches the desired particle size.

[Problems to be Solved by the Invention] As described above, the particles that are carried by the hot air current rising inside the casing and flow into the separator are classified into coarse particles and fine particles by the classification action of the separator. . In this case, it would be ideal if the coarse particles with a particle size larger than the predetermined particle size would fall from the bottom of the separator toward the table surface, and only the fine particles would be extracted from the casing through the outlet, but in reality, This kind of ideal classification is not achieved, and some of the coarse particles are drawn out of the casing through the discharge port, while some of the fine particles are also returned to the table surface. Problems arise, such as coarser particle size (decreased pulverization efficiency due to over-pulverization), and increased pressure loss (including increased fan power consumption) due to increased circulation of fine powder.

[Means for Solving the Problems] The present invention comprises a casing having an outlet at the top for fine powder conveyed by airflow, a separator provided at the upper part of the casing, a rotary table installed in the casing, and a The separator includes a plurality of crushing rollers disposed on the rotary table 1-, and the separator includes a cylindrical hood provided coaxially with the discharge port, and an air flow introduction hole provided around the upper part of the hood. 1, a li provided at the inlet, and a vane for swirling the flow, in which an airflow guide member is disposed coaxially with the outlet in a portion of the separator on the inner peripheral side of the vane. This is a vertical crusher characterized by forming an air flow passage whose height decreases as it approaches the discharge port.

[Function] In the present invention, a cone-shaped airflow guide member is provided in the separator, and the airflow introduced into the casing with swirling force applied by the vane is directed between the separator top plate and the guide member. It flows toward the center of the cone while swirling between the two, reaches the outlet, and flows out of the casing. Then,
The distance between the guide member and the casing top plate gradually decreases toward the center of the cone, and the swirling flow velocity is increased at the center of the cone compared to the case without a cone. This makes it possible to perform so-called sharp classification with narrower classification points than in the case of conventional methods, and the above-mentioned problems are solved.

[Example] FIG. 1 is an overall schematic vertical sectional view showing an example of a vertical crusher according to the present invention.

In FIG. 1, the crusher l is a rotary table 3 which will be described later.
The casing 20 is equipped with a casing 20 that stores the entire crushed group, and this casing 20 has a lower casing 20a formed in a cylindrical shape and fixed to the floor surface, and an inner cone 20c with a circular cross section that is drawn in the middle. Middle part casing 2
0b, and an upper casing 20d joined to the L end thereof.

A reducer 2 with a motor is disposed in the center of the lower casing 20a, and a rotary table 3 formed in a disc shape is attached to the output shaft facing upward. It is driven and rotates clockwise when viewed from the side in FIG. Reference numeral 5 denotes a roller post arm, and a plurality of roller post arms are disposed on the outer circumferential end of the rotary table 3, each having a conical crushing roller 4 mounted on the head and pivotally mounted on the end thereof. is pivoted.

The roller post arm 5 has an annular shape (
In this embodiment, a pressure frame 6 having an annular shape (in the present embodiment) is fixed by means such as bolt tightening, and a plurality of crushing rollers 4, roller post arms 5, and pressure frame 6 are integrally formed, and a rotary table It is placed on the 6th side of 3. on the other hand,
The upper outer peripheral end of each roller post 5 is rotatably connected to a hydraulic cylinder 10 via a connecting rod 8, a turnbuckle 9, and a cylinder rod 10a by a pin 7 and a fork end 7a, and the lower end of the hydraulic cylinder 10 is connected to a rotary pin 11. and is connected to a base plate 13 by a rotating seat 12.

Each crushing roller 4 is connected to a roller post 5 via a roller car 4a.
The rotary table 3 is rotatably supported on a shaft, and its circumferential surface is in contact with the outer circumferential surface of the L end of the rotary table 3, so that it can be rotated in accordance with the rotation of the rotary table.

On the other hand, above the center of the rotary table 3, there is a discharge n 2
2a is opened, and the final refined powder discharge pipe 22 is connected. Also, from above the casing, the raw material supply pipe 1
6 penetrates the ceiling wall of the discharge pipe 22 and is inserted into the discharge port 22a, and is arranged so that its lower end reaches near the bottom of the separator 15. This rX material supply pipe 16 discharges 'i? -Li casing 2 through 22
Around this raw material supply pipe 16, a separator 15 formed of an inverted conical cylinder is supported by the middle casing 20b by a stay (not shown).

A swirling force is applied to the inflowing dust gas on the upper surface of the outer sluice at the upper end of this separator 15! IIrIr-one 1 for
A plurality of bearings 5a are arranged evenly in the circumferential direction, and one end is connected to a bearing 15.
The shaft 15b and the handle 15d are rotatably supported by the shaft 15b and the handle 15d, and can be adjusted from the outside. gas passage 22
b, a cone-shaped gas-liquid guide member 22
c is provided.

On the other hand, below the outer periphery of the rotary table 3, an annular hot air passage 21 is provided which is connected to the hot air generator by a duct 18. Above the hot air passage 21, the rotary table 3 and the casing 20a Inner IF-14 between
An annular space 14 is defined by the outer peripheral wall t 4 b and the outer peripheral wall t 4 b. In this annular space 14, a plurality of plate-shaped blades 14c are arranged and fixed at equal intervals around the circumference while maintaining a certain angle of inclination with respect to the water -+1- plane.

Further, at the lower part of the hot air passage, there is a structure in which foreign matter during crushing and surplus material to be crushed in the event of overload can be temporarily discharged through a rotatable discharge door 19b.

The operation of the crusher configured as above will be explained next.

After starting the motorized deceleration j12 and rotating the rotary table 3, the material to be crushed is supplied from the supply pipe 16 to the center of the upper surface of the rotary table 3 while maintaining airtightness by a conveyor such as a conveyor (not shown). Due to the rotation of the rotary table 3 and the centrifugal force of the rotation, the object to be crushed moves toward the outer periphery of the rotary table 3 in a spiral trajectory. Since the crushing roller 4 rotates on the outer periphery of the rotary table 3, most of the moving object to be crushed is caught between the crushing roller 4 and the rotary table 3, and is crushed by compression, impact, and shearing action. It becomes a fine powder. This fine powder and the coarse particles and intermediate particles that have come off the periphery of the rotary table 3 without being bitten by the crushing roller 4 fall into the annular space 14, but at this time, hot air is generated! The hot air sent through the duct 1-18 by the A position is heated, and the fine powder and intermediate particles are removed together with the hot air.
Turn the inside of the crusher up) 4. The fine powder and intermediate particles that have risen are
It ascends between the separator 15 and the inner cone 20c of the casing, changes its course direction horizontally near the top part of the casing 20d, and spirally flows in along the set inclination of the IIf moving vane 15a. .

In this way, the fine powder, which has been classified by the centrifugal classification action of the separator and has reached the desired fine particle size, is sent to the next step via the discharge pipe 22. On the other hand, coarse powder that does not reach the fine particle size slides down the inner surface of the separator and accumulates near the flap 15f whose upper end is rotatably supported on the scar (15e) fixed to the side wall of the supply pipe 16.
While pushing this flap 15f away by gravity, it slides down the inner surface of the lower chute 15g and falls onto the L surface of the rotary table 3.

According to one aspect of the present invention, a cone-shaped guide member 22c is provided, and one passage 22b has an m-shaped configuration such that the height becomes smaller as it approaches the discharge port 22a, so that one classification becomes sharp.

The reason for this will be explained below with reference to FIG.

FIG. 3 is a plan view for explaining the operation of the centrifugal separator employed in the present invention.

In this centrifugal separator, a swirling force is applied to the airflow by the vanes 15a, and the airflow forms a swirl as shown by arrow Y and flows to the discharge port 20a. Particles are transported in this airflow, and the particles P are caused by the radial component a of the transport force received from the swirling flow Y and the circumferential component vcosO of the particle flow velocity V in the swirling direction. centrifugal force is applied.

Then, coarse particles to which a centrifugal force greater than the force a is applied are swept outward and separated, and small particles to which a centrifugal force smaller than the force a is applied are carried by airflow and flow toward the center.

By the way, in general, in a swirling flow, the closer the flow is to the center, the closer the flow is in the radial direction, and the radial component a of the transport force that particles receive from the swirling flow also becomes larger.

Therefore, in the conventional separator shown in Fig. 2, when coarse particles that are not separated in the outer part due to various reasons enter the inside of the swirling flow, they become increasingly separated.
Larger particles were not separated and were easily mixed with the product and flowed out from the outlet.

On the other hand, in the separator adopted in the present invention,
The closer the outlet 22a is to the airflow passage, the narrower the airflow passage becomes. Therefore, the closer the airflow is to the inside of the swirl, the higher the flow velocity of the airflow becomes. As a result, the centrifugal force applied to each particle increases, and the radial force a and centrifugal force A are balanced, and the particles are sharply classified with a predetermined particle size as the boundary.

Note that FIG. 2 is a diagram showing a separator configuration in a conventional crusher, and a short tube 2 is inserted from the opening edge of the discharge port 22a.
The structure is the same as that shown in Fig. 1 except that 2d is installed vertically.

4 and 5 respectively show another embodiment of the present invention, a guide member 22f having a gentle slope on the center side (although the center side may be horizontal) and a guide member 22f with a steep slope on the outer peripheral side, respectively. is a crusher equipped with a curved guide member 22g.

The separator of the crusher shown in FIGS. 4 and 5 similarly performs sharp classification.

FIG. 6 shows the average particle size ratio when limestone is pulverized with various guide vane angles; fine pulverization is possible by appropriately selecting the vane angle.

In addition, in the present invention, the liner of the rotary table may not be a flat type, but may be of an inclined type or a plate type, and the corresponding crushing roller may be changed to a type that is compatible with these types.

[Effects of the Invention] As is clear from the explanation below, the pulverizer of the present invention is equipped with a separator that efficiently classifies the pulverized material, and improves product precision, pulverization efficiency, and fan Effects such as reduction in power cost can be obtained. 4. Explanation for side A: Fig. 1 is an overall schematic sectional view showing an embodiment of a vertical crusher according to an uninvented invention, and Fig. 2 is a conventional example. FIG. 3 is an explanatory view of the operation of the separator, and FIGS. 4 and 5 are cross-sectional views showing different embodiments.

FIG. 6 is a graph showing partial classification efficiency and f-average particle size ratio.

1... Vertical crusher, 3... Rotating table.

4... Grinding roller, 6... Pressure frame, 14...
...Annular space portion, 15g...Separator chute, 22a...Exhaust air passage, 22b...Airflow passage.

22c, 22f, 22g... guide members.

Claims (1)

[Claims] a casing having an outlet at the top for fine powder to be carried by airflow; a separator provided at the upper part of the casing;
The separator includes a rotary table installed in a casing and a plurality of crushing rollers placed on the rotary table, and the separator includes a cylindrical hood provided coaxially with the discharge port, and a cylindrical hood provided on the top of the hood. A circumferential airflow inlet;
In a crusher equipped with a vane for swirling airflow provided at the inlet, an airflow guide member is provided coaxially with the outlet in a portion of the separator on the inner peripheral side of the vane, and the airflow guide member is provided coaxially with the outlet. A vertical crusher characterized by forming an airflow passage whose height decreases as it approaches the discharge port.