JPH0576793A - Pulverizing equipment - Google Patents

Abstract

PURPOSE:To provide highly efficient pulverizing equipment provided with a high-performance classifier capable of obtaining a product having a small average particle diameter and a sharp particle diameter distribution. CONSTITUTION:This pulverizing equipment is provided with a vertical crusher 1 having a turntable and a crushing roller, a classifier 100 wherein a dust-contg. gas contg. the crushed product is introduced and classified, a dust collector 200, a suction fan 300, a centrifugal fluidized crusher 400 wherein the collected fine powder is supplied and crushed, a dust collector 500 and a suction fan 600. The classified coarse powder in the classifier 100 is again supplied to the vertical crusher 1 through a transportation line.

Description

Detailed Description of the Invention

[0001]

The present invention relates to the fields of calcium carbonate, toners, paints, pigments, steel, metals, non-ferrous metal materials,
The present invention relates to a fine pulverization equipment which is used for all powder industries such as foods and medicines, and which efficiently pulverizes lumps or granular raw materials to, for example, several tens of microns to submicrons.

[0002]

2. Description of the Related Art As a kind of crusher for finely crushing chemicals such as limestone, blast furnace slag, and cement raw material into powder, as shown in FIG. 3, a vertical crusher equipped with a rotary table and crushing rollers. 1 is widely used. This type of crusher has a motor 2 at the bottom of the cylindrical casing 15.
A disk-shaped rotary table 3A which is driven by a speed reducer 2 by A to rotate at a low speed, and a plurality of crushing rollers 4 which are driven to rotate by being pressed by hydraulic pressure or the like at locations equally dividing the outer peripheral portion of the upper surface thereof in the circumferential direction. Is equipped with.

The crushing roller 4 is connected to a piston rod 10 of a hydraulic cylinder 9 via an arm 5 and an arm 7 which are pivotally supported by a shaft 15 by a shaft 6, and by operating the hydraulic cylinder 9, The crushing roller 4 is pressed against the rotary table 3A to apply crushing pressure to the raw material. 3B is a dam ring provided on the outer peripheral edge of the rotary table 3A for adjusting the raw material layer thickness, 14 is a gas blowing annular space passage around the rotary table 3A, 14A is a gas supply passage, and 13 is a raw material crushed by blades 13A. A rotary separator for classification, 16 is an outlet for taking out a product together with gas, and 17 is a raw material charging chute.

In such a vertical crusher, the raw material supplied to the central portion of the rotary table by the raw material feeding chute 17 receives the centrifugal force in the radial direction of the rotary table 3A and slides on the rotary table 3A. At times, the rotary table 3A receives a force in the rotation direction, and the rotary table 3A
It slides with A and performs a rotation somewhat slower than the rotation speed of the rotary table 3A. The above two forces, that is, the radial direction force and the rotational direction force are combined, and the raw material is the rotary table 3.
A spiral locus is drawn on A to move to the outer peripheral portion of the rotary table 3A. Since the roller is pressed against the outer periphery and is rotating, the raw material in which the spiral is drawn enters the crushing roller 4 and the rotary table 3A from a direction forming an angle with the roller axial direction and is bitten. It is crushed and crushed.

On the other hand, at the base of the casing 15, gas such as air or hot air is introduced by a duct,
This gas blows up from the annular space portion 14 between the outer peripheral surface of the rotary table 3A and the inner peripheral surface of the casing, so that the pulverized fine powder is entrained in the gas and the casing 1
5, the blade 1 of the separator 13 that is located in the upper part
The product having a predetermined particle size is subjected to the classification action by 3A and is discharged together with the gas from the discharge port 16 and sent to the next step.

In recent years, the demand for the product particle size of pulverized raw materials has been increasing year by year, and it has become more and more desired to make the product particle size finer, which is called fine pulverization or ultrafine pulverization. Therefore, it becomes difficult to meet the demand with a single crusher. Therefore, for example, a vertical crusher is used as a preliminary crusher before the raw material is charged into a finishing mill such as a ball mill or a centrifugal fluidizing crusher. A method has been adopted in which pulverized products of a vertical pulverizer are sieved with a vibrating screen and only fine powder is supplied to a finishing mill.

FIG. 7 is an overall vertical cross-sectional view of the centrifugal flow device 400. The structure of the centrifugal flow device 400 will be described with reference numeral 40.
Reference numeral 8 is a casing that covers the main body of the crusher, and the fixed ring 407 is connected to the casing 408 via a connecting member 409.
It is mounted on the inner surface of. Reference numeral 410 is a pedestal, which pivotally supports the rotating dish 406 via a bearing 411. The rotating shaft 402 is connected to a prime mover such as an electric motor via a reduction mechanism or the like. A raw material feeding pipe 412 is installed in a central portion of the ceiling of the casing 408, and an opening 413 is provided so as to surround the feeding pipe 412, and a duct 414 is connected to the opening 413.

In this embodiment, the fixed ring 407 is lined with a liner, and a number of slits or small holes 415 are formed so as to penetrate the wall surface thereof. Fixed ring 407
A side cover 416 is provided between the bottom of the outer surface and the inner surface of the casing 408. An air introduction chamber 417 is defined between the side cover 416 and the outer surface of the casing 408 and the fixed ring 407. Air can be introduced from the introduction pipe 418. The upper end of the side cover 416 is sealed to the outer side surface of the fixed ring 417.

On the other hand, the outer peripheral edge of the rotary plate 406 and the fixed ring 40
7 to the inner peripheral edge of the bottom of the
% Clearance 419, bottom cover 42
0 is circumferentially provided so as to cover the lower side of the clearance 419. In this embodiment, air can be introduced into the bottom cover 420 by forming a through hole in the side cover 416 or connecting an air introduction pipe.

The bottom cover 420 and the air introducing chamber 4
A pipe line 421 for extracting and conveying the powder or granular material is connected to the pipe 17, and the pipe line 421 is arranged so that the powder or granular material can be returned to the charging pipe 412. Further, a scraper 422 is fixedly provided on the lower side of the outer peripheral edge of the rotary plate 406, and the bottom cover 42
It is configured such that the powder particles that have fallen into the inside of 0 are gathered toward the connecting portion of the pipe line 421 for extraction. In addition, duct 4
14 is normally connected to a powder collecting means (not shown) such as a back filter. (A classifying unit may be installed upstream of the collecting unit.)

In the crushing device configured as described above,
The raw material is introduced into the apparatus through the introduction pipe 412. Rotating dish 4
Along with the rotation of 06, the ball 423 performs a spiral motion that twists the rope by combining the circular motion that circulates between the inner wall surface of the fixed ring 407 and the plate surface and the revolution motion around the axis of the rotary plate 406. In the meantime, the raw materials are crushed. Air introduction pipe 41
The air introduced into the air introduction chamber 417 and the bottom cover 420 from the No. 8 flows into the crushing chamber through the clearance 419, the slits or the small holes 415, and enters the duct 414 together with the powder generated by the crushing and classifies. It is sent to a means or a collection means. The fine particles entrained in the air are collected by the collecting means. Further, in the present embodiment, the air flow from the small holes 415 and the clearance 419 acts to blow off the raw material (raw material powder) at the inner peripheral surface position of the fixed ring 407, but the suction acting between the raw material and the fixed ring 407. This effect is small due to the force, and efficient grinding is possible.

If a classifying means is installed on the downstream side in the duct 414 and particles having a relatively large particle size can be separated by this classifying means, the separated coarse particles are fed again. It is put into the apparatus through 412. Also, slits or small holes 415 or clearances 4
The particles that have exited the crushing chamber through 19 are returned to the crushing chamber by the pipe line 421. This device is, for example, 2
It is rotated at 00-3000 rpm. There are 3 balls
A diameter of approximately 70 mm is suitable.

[0013]

[Problems to be Solved by the Invention] However, recently,
The demands on the particle size distribution of products are increasing with the diversification of pulverized raw materials and the expansion of the demand for ultrafine powders. Not only is a fairly fine average particle size required, but the range of particle size distribution is limited. In other words, strict products have come to be demanded, for example, the condition that a sharp particle size distribution curve has to be imposed. Along with this, it has been eagerly desired to improve the performance of the crusher and to have a classifier with high capacity and excellent classifying performance, and it is hoped that a system that combines these well will be provided with an efficient fine crushing facility. It was

[0014]

In order to solve the above-mentioned problems, in the fine crushing equipment of the present invention, a plurality of rotatable crushing rollers are arranged on the upper surface of the outer peripheral portion of the rotary table, and the supplied raw material is crushed by the crushing rollers. A vertical crusher for applying a predetermined crushing pressure to the crusher between the upper surface of the rotary table and the peripheral surface of the crushing roller, and a classifier for introducing and classifying dust-containing gas containing crushed products of the vertical crusher. A dust collecting device and a suction fan for collecting the fine powder after classification by the classifying device, a centrifugal fluidizing and pulverizing device for supplying and pulverizing the fine powder collected by the dust collecting device, and a refined powder of the centrifugal fluidizing and pulverizing device A fine pulverizing equipment comprising a dust collecting device and a suction fan for collecting the dust, which is provided with a transportation path for re-supplying the coarse powder after the classification in the classifying device to the vertical pulverizer. Is a cylinder and an inverted truncated cone A hollow casing having a driving shaft composed of a hollow tube rotatably supported concentrically in the center of a casing having a shape, and a plurality of circumferentially rotating classification blades integrally rotating around the hollow shaft; A discharge pipe for fine powder after classification is provided on the upper side, and a plurality of guide vanes rotatable around a vertical axis for giving a swirl to the dust-containing gas on the outer circumference of the classification blade are concentric with the hollow pipe. And a guide cone connected to the guide vane at a lower portion of the guide vane, the guide cone having a substantially truncated truncated cone shape. The classifying blade is provided on the casing at the height of the guide vane. A plurality of dust-containing gas supply pipes are arranged tangentially in the direction of rotation of the, the guide cone is provided with a plurality of arc-shaped slits along the circumferential direction, and From the point where the frustoconical shape is formed, The direction of rotation of 該分 class blade the intake of use air has a configuration which is arranged in the casing in the opposite tangential direction.

[0015]

In the fine pulverizing apparatus of the present invention, a lump or granular raw material is pulverized by a vertical pulverizer in advance, and a gas containing a powder or granular material which is a pulverized product is introduced into a classifying apparatus for classification, and after classification, The coarse powder is re-supplied to the vertical crusher again for pulverization, and the fine powder after classification is collected by the dust collector and supplied to the centrifugal fluidizing pulverizer for pulverization. Therefore, since the fine powder having a certain particle size or less is supplied to the centrifugal fluidizing and pulverizing apparatus, the ball diameter of the pulverizing medium stored in the centrifugal fluidizing and pulverizing apparatus can be made small and efficient fine pulverization can be carried out. The crushed fine powder is collected by a dust collector to be a product.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 5 show an embodiment of the present invention, FIG. 1 is an overall flow sheet, FIG. 2 is a vertical sectional view of a classifier, FIG. 3 is a plan view taken along line III-III of FIG. 2, and FIG. IV-
FIG. 5 is a plan view seen from IV, and FIG. 5 is an overall flow sheet showing another embodiment.

In the figure, 1 is a vertical crusher, whose structure is as described in the prior art, 100 is a classifier,
Reference numeral 200 is a dust collector, 300 is a suction fan, 400 is a centrifugal flow pulverizer, the structure of which is as described in the prior art, 500 is a dust collector, and 600 is a suction fan.
As shown in FIGS. 2 to 4, the classifying device 100 is a pair of upper and lower parts fitted to a pedestal 106 that is erected upright in the upper center of the casing 102, which is composed of a cylindrical casing 102a and a truncated truncated cone-shaped casing cone 102b. Bearings 104,1
The hollow tube 103 pivotally supported by 05 is configured to be rotationally driven. That is, the chain wheel 107 fixed to the outer periphery of the hollow tube 103 near the upper end is the roller chain 10.
A chain wheel 110 attached to the output shaft of the variable speed electric motor 109 through 8 drives it to rotate at an arbitrary speed. On the other hand, below the hollow tube 103 are a plurality of horizontal discs 1
A plurality of classifying blades 112 are arranged vertically around the outer circumference of 11, and a support 11 is provided on the outer circumference of the classifying blade 112.
A rotary shaft 113 rotatably erected via a bearing 113b on an upper end flange of an inverted truncated cone-shaped guide cone 114 fixedly mounted on a casing cone 112b via a shaft 4a.
A plurality of guide vanes 113 that can be rotated around a are arranged. As shown in FIG. 3, the inclination of the guide vanes 113 is set in a direction in which the air flow of the dust-containing gas flowing in synchronism with the rotation direction of the classification blade 112 (clockwise in this embodiment) is a swirling flow. Similarly, the inclination of the classification blades 112 is also arranged in the same direction as the inclination of the guide vanes 113 and is in the spiral direction.

Guide vanes 113 of casing 102a
As shown in FIG. 3, four dust-containing gas supply pipes 116 are tangentially installed at positions facing each other so that the dust-containing gas flows between the guide vanes substantially evenly. There is. Reference numeral 115 is a top plate that covers the upper portion of the classification blade 112. As shown in FIG. 4, a plurality of horizontal arc-shaped slits 114b are provided at equal intervals in the middle of the guide cone 114, and the inlet of the classification airflow is located at a position of the casing cone 102b facing the slit 114b. 118
Are arranged in a tangential direction opposite to the supply pipe 116 (two in this embodiment). The airflow that has flowed in through the intake 118 is the casing cone 102b and the casing 102.
Along the line “a”, the fine particles of the powder that enters the slit 114 b of the guide cone 114 and slides down the inner surface of the casing or the inner surface of the guide cone are conveyed to the classification vane 112 again. The tangential mounting direction of the inlet 118 is opposite to the tangential mounting direction of the supply pipe 116 (counterclockwise in this embodiment).
This is to break up the agglomeration of the powder that falls in a spiral shape in the clockwise direction, and to facilitate the transport of fine powder by air flow.

A fine powder discharge pipe 117 after classification is fixedly mounted on the upper end of the hollow pipe 113 via a bearing 119. A lid 103a is provided at the lowermost end of the hollow tube 113 to prevent a short path of airflow. A coarse powder service hopper 120 is provided at the lower end of the casing cone 102b via a flange, and is connected to a crusher (not shown) located downstream.

Next, the operation of the classifying device 100 of the present invention constructed as above will be described. When the dust-containing gas containing the raw material powder is introduced into the classifying device 100 through the supply pipe 116, the dust-containing gas forms a swirl flow due to the inclination of the guide vanes 113 and the action of the rotating classifying blade 112, and the dust-containing gas is substantially circled. The particles are evenly distributed and flow between the classification blades 112 to be classified. As a result of the classification, fine powder below the classification point is discharged from the discharge pipe 117 through the inside of the hollow tube 103, but coarse particles above the classification point and agglomeration to cause particle groups apparently larger than the classification point are generated. It is removed by the classifying blade 112 and is repelled, collides with the inner surfaces of the casing 102a and the guide cone 114, and falls downward. However, in the classifying device of the present invention, air is introduced from the inlet 118 provided in the middle of the casing cone 102b, and this air is the same as the dust-containing gas, and the suction force of the suction fan arranged downstream of the classifying device 100. By entering the casing 102 and the slit 114b of the guide cone 114 by the guide cone 1
Since it goes up in the inside of 14, the fine particles adhering to or mixed with the above-mentioned falling coarse particles and coarse powder are conveyed again to the classification blade 112 to be subjected to the classification action. As a result, coarse particles and fine powder in the coarse powder can be recovered, and the fine powder in the raw material to be re-supplied to the crusher can be reduced as much as possible. The tangential mounting direction of the intake 118 is classified by the blade 112
As described above, the reason why the direction of rotation of the above, that is, the direction in which the tangential line of the supply pipe 116 is installed is opposite, is that the agglomerates of the powder mainly falling in the rotational direction in the direction of rotation are destroyed to disperse the fine powder into pieces. This is to facilitate the recovery of fine powder. In this way, the fine powder in the return dressing 11
The behavior after being subjected to the classification action by 2 is as described above, and the fine powder below the classification point is discharged from the discharge pipe 117, and the coarse powder above the classification point is removed and returned again. After the classification, the returned mash that has passed through the guide cone 114 and the casing cone 102b is stored in a service hopper (not shown) and then used for crushing again.

The adjustment of the classification point is mainly performed by controlling the rotation speed of the classification blade 112, and the inclination angle of the guide vane 113 may be changed as an auxiliary means. However, this work is interrupted and each guide vane is manually operated. Since the inclination of 113 must be changed, it is complicated and cannot be used frequently. In an actual machine in which the inclination angle of the guide vane 113 is changed frequently during operation and when it is desired to automatically change it, a micromotor is used instead of the bearing 113b that supports the rotating shaft 113a of the guide vane 113. You may change it by operation.

A bag filter or an electric dust collector is adopted as the dust collectors 200 and 500. Suction fan 300,600
Are for carrying fine powder after pulverization by air.

The operation of the fine crushing device of the present invention constituted by the respective devices arranged as described above will be described.
First, the pulverized raw material is supplied to the vertical pulverizer 1 by a transportation means (not shown) while maintaining airtightness with the outside. In the vertical crusher 1, the pulverization is performed as described in the related art, and the generated fine powder is supplied by air conveyance to the classifying device 100 downstream of the vertical crusher 1 together with the gas for classification. Coarse powders above the classification point are returned to the vertical crusher 1, and fine powders below the classification point are collected by the dust collector 200 and fed into the centrifugal fluidized pulverizer 400 arranged directly below. The fine powder crushed by the centrifugal fluidizer 400 is collected by the dust collector 500 together with air to be the final product. The above is the raw material flow in the embodiment of the present invention having the flow sheet shown in FIG. 1. Further, if strict conditions are required for the particle size composition of the fine powder of the product, as in the flow sheet shown in FIG. , A classifier 7 having the same structure as the classifier 200 as required
00 is placed between the centrifugal fluidizer 400 and the dust collector 500, the classification point is adjusted so as to satisfy the specified conditions, and then the product is extracted.

In the fine pulverizing apparatus of the present invention, the pulverized large-diameter raw material is pulverized in advance by the vertical pulverizer, and is supplied to the centrifugal fluidizing apparatus, so that the pulverizing ratio is large, for example, 10.
Not only fine powder products of several microns to submicrons can be obtained, but because a high-performance classifying device with high classification efficiency is placed between the vertical crusher and the centrifugal fluidizer, fine crushing with excellent crushing efficiency is achieved. It can be equipment.

[0025]

As described above, in the fine crushing equipment of the present invention, crushing with a high crushing ratio is performed, and
A fine powder with a small average particle size, which has a sharp particle size distribution curve limited to a range with a wide particle size distribution, is obtained, and since the classification performance is high, efficient pulverization is carried out, resulting in a running cost. It can be reduced.

[Brief description of drawings]

FIG. 1 is an overall flow sheet showing an example of a fine crushing facility of the present invention.

FIG. 2 is a vertical cross-sectional view of a classification device according to an embodiment of the present invention.

FIG. 3 is a plan view taken along line III-III in FIG.

FIG. 4 is a plan view taken along line IV-IV of FIG.

FIG. 5 is an overall flow sheet showing another embodiment of the fine pulverization equipment of the present invention.

FIG. 6 is an overall vertical sectional view of a conventional vertical crusher.

FIG. 7 is a vertical cross-sectional view of a conventional centrifugal fluidizing and grinding apparatus.

[Explanation of symbols]

 1 Vertical crusher 100 Classifier 112 Classifier blade 113 Guide vane 114 Guide cone 114b Slit 200 Dust collector 300 Suction fan 400 Centrifugal fluid crusher 500 Dust collector 600 Suction fan 700 Classifier

Claims (1)

[Claims] 1. A plurality of rotatable crushing rollers are arranged on the upper surface of the outer periphery of a rotary table, and the supplied raw material is crushed between the upper surface of the rotary table and the peripheral surface of the crushing roller by applying a predetermined crushing pressure to the crushing roller. A vertical crusher, and a classifying device for introducing and classifying dust-containing gas containing pulverized products of the vertical crusher,
A dust collecting device and a suction fan for collecting fine powder after classification by the classifying device, a centrifugal fluidizing and pulverizing device for supplying and pulverizing the fine powder collected by the dust collecting device, and a fine powder for the centrifugal fluidizing and pulverizing device. A fine pulverizing equipment comprising a dust collecting device for collecting and a suction fan, comprising a transportation route for re-supplying the coarse powder after the classification in the classifying device to the vertical crusher, the classifying device comprising: , A drive shaft consisting of a hollow tube that is rotatably supported concentrically in the center of a casing consisting of a cylinder and an inverted truncated cone shape, and a plurality of classification blades that rotate integrally around the drive shaft. A discharge pipe for fine powder after classification is provided above the hollow pipe, and a plurality of guide vanes are provided on the outer circumference of the classification blade, the guide vanes being rotatable about a vertical axis for giving swirling to dust-containing gas. Individually arranged concentrically with the hollow tube, and A classifier which is connected to the guide vane in a portion thereof and is provided with a guide cone having a substantially truncated truncated cone shape, wherein the casing at the height of the guide vane is tangential to the casing in the direction of rotation of the classifying blades. Around the place where a plurality of dust-containing gas supply pipes are arranged, a plurality of arc-shaped slits along the circumferential direction are provided in the guide cone, and a truncated truncated cone shape of the casing is formed. A fine pulverization facility in which a plurality of peripheral air intakes for classification are arranged in the casing in a tangential direction opposite to the rotation direction of the classification blades.