WO2016104224A1

WO2016104224A1 - Vertical roller mill

Info

Publication number: WO2016104224A1
Application number: PCT/JP2015/084962
Authority: WO
Inventors: 信雄時岡; 文典安藤; 大輔笠井; 伸一宮川
Original assignee: 川崎重工業株式会社
Priority date: 2014-12-22
Filing date: 2015-12-14
Publication date: 2016-06-30
Also published as: EP3238824A1; EP3238824B1; EP3238824A4; JP6656805B2; JP2016117042A; CN105709884B; CN205599248U; CN105709884A

Abstract

This vertical roller mill comprises: a rotating table having a crushing surface; a crushing roller (3) for nipping and crushing a raw material between the crushing roller (3) and the crushing surface; and a scraper (13) for adjusting the layer thickness of the raw material supplied to the crushing roller (3). The scraper (13) has: a scraper body (15) disposed above and at a distance from the crushing surface of the rotating table; a movement means (16) capable of moving the scraper body (15) in the direction away from the crushing surface; and a resistance application means (17) for applying resistance to the movement of the scraper body (15) in the direction away from the crushing surface. Even if the layer thickness of the raw material having been supplied on to the crushing surface of the rotating table varies, the position in height of the scraper is adjusted automatically according to the variation in the layer thickness.

Description

Vertical roller mill

The present invention relates to a vertical roller mill that crushes by crushing a raw material between a crushing roller and a rotary table.

Conventionally, vertical roller mills that pulverize by crushing raw materials between a pulverizing roller and a rotary table have been used for pulverizing clinker, slag, and the like. In the vertical roller mill, a raw material made of slag, clinker, or the like is supplied onto the central portion of the rotary table via a raw material charging chute. The rotary table is driven to rotate around a vertical rotation axis.

The raw material supplied on the center of the rotary table moves radially outward by the centrifugal force generated by the rotation of the rotary table, and is supplied onto the annular grinding surface formed on the rotary table.

In addition, a separator is provided above the rotary table inside the mill casing, and raw materials (coarse powder) coarser than a desired particle size (particle size) are classified by the separator and refluxed to the center of the rotary table. The The raw material (coarse powder) recirculated onto the center of the rotary table is supplied onto the pulverized surface of the rotary table by the centrifugal force of the rotary table together with the raw material charged from the raw material charging chute.

The raw material supplied on the circular crushing surface of the rotary table is rotated and moved by the rotary operation of the rotary table, and is caught between a plurality of crushing rollers and the rotary table. Each of the plurality of grinding rollers is elastically pressed toward the grinding surface of the rotary table by a roller pressing mechanism having a hydraulic cylinder or the like. The raw material caught between the crushing roller and the rotary table is crushed by the pressing force of the crushing roller.

By the way, in the pulverization processing of cement, slag, etc. using a vertical roller mill, if the thickness (layer thickness) of the raw material to be pulverized on the annular pulverization surface of the rotary table is not constant, Move up and down. When the crushing roller is moved up and down, vibrations are caused in the mill, which adversely affects the stable operation of the mill.

In order to cope with this problem, in the conventional vertical roller mill, a scraper is provided on the biting side of the grinding roller. The scraper is installed above a predetermined distance from the grinding surface of the rotary table, and is fixed to a support beam above the rotary table.

The scraper leveles the raw material to make the layer thickness uniform before the raw material is caught in the gap between the grinding roller and the rotary table, thereby reducing mill vibration during grinding due to fluctuations in the raw material layer thickness. To do.

Japanese Patent Laid-Open No. 3-174258

By the way, the layer thickness of the raw material supplied on the crushing surface of the rotary table varies depending on the production type, the production amount, the operation parameters (raw material input amount, etc.), and the scraper has an optimum height corresponding to the layer thickness.

However, since the conventional scraper is fixedly installed above the rotary table as described above, it is necessary to perform the work when the mill is stopped in order to change its height. If the mill is temporarily stopped every time the layer thickness fluctuates and the height adjustment operation of the scraper is performed, the operation efficiency of the mill is lowered.

The present invention has been made in view of the above-mentioned problems of the prior art, and even when the layer thickness of the raw material supplied on the pulverizing surface of the rotary table varies, the scraper is changed according to the variation of the layer thickness. An object of the present invention is to provide a vertical roller mill whose height position is automatically adjusted.

In order to solve the above problems, a vertical roller mill according to a first aspect of the present invention includes a rotary table having a pulverizing surface, a pulverizing roller for biting and pulverizing a raw material between the pulverizing surface, A scraper for adjusting the layer thickness of the raw material supplied to the crushing roller, wherein the scraper is spaced apart above the crushing surface, and the scraper main body is separated from the crushing surface. Movable means for making it possible to move in the direction of leaving, and resistance applying means for giving resistance to movement of the scraper body in the direction of going away from the grinding surface.

The second aspect of the present invention is characterized in that, in the first aspect, the mobilization means is configured to suspend the scraper body so as to be swingable around a horizontal axis.

According to a third aspect of the present invention, in the first or second aspect, the scraper body has a contact surface with the raw material, and the contact surface faces obliquely downward in a stationary state of the scraper body. It is characterized by that.

The fourth aspect of the present invention is characterized in that, in the third aspect, the contact surface of the scraper body forms an angle of 15 ° to 75 ° with respect to a vertical surface.

The fifth aspect of the present invention is characterized in that, in any one of the first to fourth aspects, the resistance applying means has a weight for urging the scraper body downward.

The sixth aspect of the present invention is characterized in that, in the fifth aspect, the weight of the weight is adjustable.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, the scraper further includes a movable range regulating means for regulating an operable range of the scraper body. And

The eighth aspect of the present invention is characterized in that, in the seventh aspect, the movable range restricting means is configured to be capable of adjusting a lowermost position and an uppermost position of the scraper body.

The ninth aspect of the present invention is characterized in that in any one of the first to eighth aspects, a dust cover provided around the mobilization means is further provided.

According to a tenth aspect of the present invention, in any one of the first to ninth aspects, the scraper body has a contact surface with the raw material, and a lower portion of the contact surface is formed thick. It is characterized by that.

According to the present invention, there is provided a vertical roller mill in which the height position of the scraper is automatically adjusted according to the variation of the layer thickness even when the layer thickness of the raw material supplied on the grinding surface of the rotary table varies. The purpose is to do.

The longitudinal cross-sectional view which showed schematic structure of the vertical roller mill by one Embodiment of this invention. The top view for demonstrating arrangement | positioning of the movable scraper in the vertical roller mill shown in FIG. The front view which showed the movable scraper of the vertical roller mill shown in FIG. The side view which showed the movable scraper of the vertical roller mill shown in FIG. The side view for demonstrating operation | movement of the movable scraper of the vertical roller mill shown in FIG. The other side view for demonstrating operation | movement of the movable scraper of the vertical roller mill shown in FIG. The perspective view which showed the dust cover of the movable scraper of the vertical roller mill shown in FIG. The schematic diagram for demonstrating the effect | action of the movable scraper of the vertical roller mill shown in FIG. The schematic diagram for demonstrating the effect | action of the fixed scraper of the conventional vertical roller mill.

Hereinafter, a vertical roller mill according to an embodiment of the present invention will be described with reference to the drawings.

As shown in FIG. 1, the vertical roller mill 1 according to the present embodiment includes a plurality of (this book) that squeezes the raw material between the rotary table 2 and the rotary table 2 where the raw material is supplied to the center of the upper surface. In the example, there are three) crushing rollers 3. The turntable 2 is driven to rotate about the vertical rotation axis L0.

The plurality of grinding rollers 3 are arranged at equiangular intervals on a virtual circumference centered on the vertical rotation axis L0 of the turntable 2. Each of the plurality of crushing rollers 3 is pressed toward the annular crushing surface 2a of the turntable 2 shown in FIG. 2 by a roller pressing mechanism 4 having a drive source such as a hydraulic cylinder.

The vertical roller mill 1 includes a rotary drive source 5 and a speed reducer 6 for the rotary table 2, and the rotary table 2 is installed above the speed reducer 6.

The rotary table 2 and the grinding roller 3 are covered with a mill casing 7. The supply of the raw material to the turntable 2 is performed through a raw material supply chute 8 disposed through the mill casing 7. In this example, the raw material supply chute 8 extends along the vertical rotation axis L <b> 0 of the turntable 2.

A separator 9 is provided above the rotary table 2. Of the raw materials released radially outward from the turntable 2 by centrifugal force, the raw materials pulverized more finely than a predetermined particle size (particle size) pass through the hot air duct (not shown) to the inside of the mill casing 7. Is blown up by the hot air supplied to the separator 9 and transferred to the separator 9.

The separator 9 is rotationally driven by a separator driving device 10 composed of an electric motor or the like, and among the raw materials blown up by hot air, only the raw material (fine powder) finer than the desired particle size (particle size) is placed on the upper portion of the mill casing 7. It discharges from the provided fine powder discharge duct (not shown). On the other hand, the raw material (coarse powder) coarser than the desired particle size (particle size) is classified by the separator 9 and returned to the rotary table 2 through the funnel-shaped member (inner cone) 11, and the pulverizing roller 3 and the rotary table are collected. 2 and is crushed again.

The vertical roller mill 1 includes a recovery casing 12 for recovering a raw material that has not been blown up by hot air among the raw materials released around the rotary table 2 by the centrifugal force accompanying the rotation of the rotary table 2. The recovery casing 12 has an outer diameter larger than that of the turntable 2 and has an annular shape as a whole. The raw material recovered in the recovery casing 12 is returned to the turntable 2 via an external circulation line (not shown) and pulverized again.

As shown in FIG. 2, the vertical roller mill 1 according to the present embodiment includes three crushing rollers 3, and the layer thickness of the raw material supplied to the crushing rollers 3 for each of the three crushing rollers 3. A scraper 13 for adjusting the above is installed. The scraper 13 is provided on a support beam 14 installed inside the mill casing 7.

3 and 4 show the scraper 13 in an enlarged manner. The scraper 13 includes a scraper body 15 that is spaced above the grinding surface 2a of the rotary table 2, and a raw material on the grinding surface 2a. When the scraper body 15 comes into contact with the main body 15, it has resistance against movement of the scraper main body 15 in a direction away from the grinding surface 2 a and a mobilization means 16 for enabling the scraper body 15 to move away from the grinding surface 2 a. Resistance providing means 17 (FIG. 4) for applying.

The moving means 16 is configured to suspend the scraper body 15 so as to be swingable around a horizontal axis. That is, the mobilization means 16 has a turning shaft 18 extending in the horizontal direction, and the turning shaft 18 is supported by a bearing 19 provided on the support beam 14 so as to be turnable. The swing shaft 18 is provided with a plurality of movable support members 20 extending in the vertical direction, and the movable support member 20 can swing around the swing shaft 18. A scraper body 15 is provided at the lower end of the movable member 20, and the scraper body 15 can swing together with the movable support member 20.

As shown in FIG. 4, the contact surface 15 a with the raw material of the scraper body 15 faces obliquely downward when the scraper body 15 is stationary (in the lowest position). More specifically, the contact surface 15a of the scraper body 15 forms an angle of 15 ° to 75 °, preferably 45 ° with respect to the vertical surface. In consideration of wear due to contact with the raw material, the lower portion of the contact surface 15a of the scraper body 15 is formed thick.

The resistance applying means 17 of the scraper 13 has a weight 21 that urges the scraper body 15 downward. The weight 21 is detachably attached to the lower end portion of the movable support member 20 with a bolt 22. The weight 21 is formed by superposing a plurality of plates, and the weight of the weight 21 can be adjusted by changing the number and type of the plates.

The scraper 13 further has a movable range restricting means 23 for restricting the operable range of the scraper body 15. The movable range restricting means 23 includes a first stopper member 24 for defining the lowest position of the scraper body 15 and a second stopper member 25 for defining the uppermost position of the scraper body 15.

The first stopper member 24 is capable of releasing the bolt support piece 24a provided on the upper surface of the support beam 14, the stopper bolt 24b screwed into the bolt hole formed in the bolt support piece 24a, and the stopper bolt 24b. A bolt fixing nut 24c for fixing.

The tip of the stopper bolt 24b is in contact with the upper end of the movable support member 20 positioned above the pivot shaft 18 in the stationary state of the movable support member 20 shown in FIG. Thereby, the movable support member 20 is restricted from rotating in the counterclockwise direction in FIG.

4) By loosening the bolt fixing nut 24c and adjusting the amount of protrusion of the stopper bolt 24b, it is possible to adjust the restricting position of the rotational movement of the movable support member 20 in the counterclockwise direction in FIG. Thereby, the lowest position of the scraper main body 15 can be adjusted.

In this example, as shown in FIG. 4, when the upper half of the movable support member 20 faces in the vertical direction, the tip of the stopper bolt 24 b is brought into contact with the upper end of the movable support member 20. The movable support member 20 is configured to be stationary. Thereby, when the movable support member 20 is in a stationary state, the raw material contact surface 15a of the scraper body 15 is inclined by 15 ° to 75 °, preferably 45 °, toward the grinding roller 3 with respect to the vertical direction.

The second stopper member 25 is capable of releasing the bolt support piece 25a provided on the lower surface of the support beam 14, the stopper bolt 25b screwed into the bolt hole formed in the bolt support piece 25a, and the stopper bolt 25b. A bolt fixing nut 25c for fixing.

As shown in FIG. 5, when the scraper body 15 is pushed up by contact with the raw material and the movable indicating member 20 rotates around the pivot shaft 18 in the clockwise direction in FIG. A central portion of the movable support member 20 positioned below the pivot shaft 18 is brought into contact. As a result, the movable support member 20 is restricted from rotating in the clockwise direction in FIG.

-4 By loosening the bolt fixing nut 25c and adjusting the amount of protrusion of the stopper bolt 25b, it is possible to adjust the restricting position of the rotating operation of the movable support member 20 in the clockwise direction in FIG. Thereby, the uppermost position of the scraper main body 15 can be adjusted.

Even if the lower stopper bolt 25b and the bolt support piece 25a are damaged by the pressing force of the raw material, the movable support member 20 contacts the support beam 14 as shown in FIG. Stop at. Thereby, it can prevent reliably that the movable part (for example, weight 21) of the scraper 13 contacts the crushing roller 3. FIG.

A dust cover 26 shown in FIG. 7 is provided around the movable means 16 (18, 19) of the scraper 13. Providing the dust cover 26 prevents dust from adhering around the swivel axis 18 of the scraper 13, thereby preventing malfunction of the scraper 13.

Next, the operation of the scraper 13 of the vertical roller mill 1 according to the present embodiment will be described in comparison with a conventional scraper.

As shown in FIG. 9, the scraper body 101 of the conventional scraper 100 is fixedly installed by a fixing bolt 103 via a fixing support member 102 on the biting side of the grinding roller 3. In this fixed scraper 100, the distance D between the lower end of the scraper body 101 and the grinding surface 2a of the rotary table 2 is always constant. That is, even when the layer thickness T of the raw material on the upstream side of the scraper 100 varies, the separation distance D between the lower end of the scraper body 101 and the grinding surface 2a of the turntable 2 does not change.

On the other hand, in the scraper 13 of the vertical roller mill 1 according to the present embodiment, as shown in FIG. 8, the scraper body 15 is suspended by the movable support member 20 so as to be swingable around the turning shaft 18. Yes. For this reason, when the scraper body 15 is pressed by the raw material that moves as the rotary table 2 rotates, if the pressing force exceeds the resistance force by the weight 21, the scraper body 15 together with the movable support member 20 moves around the pivot shaft 18. Rotate to. By this rotation operation, the separation distance D between the lower end of the scraper body 15 and the grinding surface 2a of the rotary table 2 is increased.

That is, in the scraper 13 of the vertical roller mill 1 according to the present embodiment, the amount of angular displacement around the swivel axis 18 of the movable support member 20 and the scraper body 15 is increased by increasing the layer thickness T of the raw material on the upstream side of the scraper 13. As a result, the distance D between the lower end of the scraper body 15 and the grinding surface 2a of the rotary table 2 is further increased.

As described above, according to the vertical roller mill 1 according to the present embodiment, the lower end of the scraper main body 15 and the grinding surface 2a of the rotary table 2 follow the fluctuation of the layer thickness T of the raw material on the upstream side of the scraper 13. The separation distance D changes. Thereby, the height position of the scraper body 15 is automatically adjusted to the optimum position according to the layer thickness of the raw material.

Further, in the vertical roller mill 1 according to the present embodiment, the raw material contact surface 15a of the scraper body 15 is inclined with respect to the vertical surface, whereby the raw material contacts the grinding surface 2a of the turntable 2 with the raw material contact surface 15a. Pressed in the direction and compressed. A part of the air contained in the raw material is expelled by the compression action of the raw material by the raw material contact surface 15a. By this degassing and compacting action of the raw material, the raw material pulverization operation by the pulverizing roller 3 can be stabilized and the pulverization efficiency can be increased.

The inclination angle of the raw material contact surface 15a of the scraper body 15 with respect to the vertical surface can achieve the above-described raw material degassing and consolidation effects, and can sufficiently secure the movable range of the scraper main body 15 to ensure the necessary adjustment range. It is preferable to determine this.

In the above-described embodiment, the vertical roller mill 1 having three crushing rollers 3 has been described. However, in the present invention, the number of crushing rollers is not limited, and there are four or more crushing rollers. Also good.

In the above-described embodiment, the weight 21 is used as the resistance applying means 17 of the scraper 13. However, instead of the weight 21, a resilient means such as a spring member or an air damper can be used.

In the embodiment described above, the movable support member 20 having a bent shape is used, but instead of this, a straight shape movable support member is used, and the raw material contact surface of the scraper body 15 in a stationary state is used. 15a may be oriented in the vertical direction.

Even in this case, the raw material contact surface 15a of the scraper main body 15 is inclined with respect to the vertical surface by rotating the scraper main body 15 together with the movable support member by the pressing force from the raw material, so that the raw material contact surface 15a compresses the raw material. Degassing from the raw materials and consolidation effect can be expected.

DESCRIPTION OF SYMBOLS 1 Vertical roller mill 2 Rotating table 2a Crushing surface of rotating table 3 Crushing roller 4 Roller pressing mechanism 5 Rotating table rotational drive source 6 Rotating table speed reducer 7 Mill casing 8 Raw material feeding chute 9 Separator 10 Separator driving device 11 Funnel-shaped member (Inner cone)
DESCRIPTION OF SYMBOLS 12 Recovery casing 13 Scraper 14 Support beam 15 Scraper main body 15a Raw material contact surface 16 Movable means 17 Resistance provision means 18 Swiveling shaft 19 Bearing 20 Movable support member 21 Weight (resistance provision means)
22 bolts (for weight fixing)
23 movable range regulating means 24 first stopper member 24a bolt support piece 24b stopper bolt 24c bolt fixing nut 25 second stopper member 25a bolt support piece 25b stopper bolt 25c bolt fixing nut 26 dust cover 100 conventional scraper 101 conventional scraper Scraper main body 102 Conventional scraper fixing support member 103 Conventional scraper fixing bolt D Separation distance between lower end of scraper main body and grinding surface of rotary table L0 Rotation axis of rotary table T Layer thickness of raw material

Claims

A rotary table having a grinding surface;
A grinding roller for biting and grinding the raw material between the grinding surfaces;
A scraper for adjusting the layer thickness of the raw material supplied to the grinding roller,
The scraper is
A scraper main body spaced apart above the grinding surface;
Mobilization means for enabling movement of the scraper body in a direction away from the grinding surface;
A saddle type roller mill having resistance applying means for applying resistance to movement of the scraper body in a direction away from the grinding surface.
The vertical roller mill according to claim 1, wherein the moving means is configured to suspend the scraper body so as to be swingable around a horizontal axis.
The scraper body has a contact surface with the raw material,
The vertical roller mill according to claim 1 or 2, wherein the contact surface faces obliquely downward in a stationary state of the scraper body.
The vertical roller mill according to claim 3, wherein the contact surface of the scraper body forms an angle of 15 ° to 75 ° with respect to a vertical surface.
The vertical roller mill according to any one of claims 1 to 4, wherein the resistance applying means includes a weight that biases the scraper body downward.
The vertical roller mill according to claim 5, wherein the weight of the weight is adjustable.
The vertical roller mill according to any one of claims 1 to 6, wherein the scraper further includes a movable range restricting means for restricting an operable range of the scraper body.
The vertical roller mill according to claim 7, wherein the movable range regulating means is configured to be capable of adjusting a lowermost position and an uppermost position of the scraper body.
The vertical roller mill according to any one of claims 1 to 8, further comprising a dust cover provided around the mobilization means.
The scraper body has a contact surface with the raw material,
The vertical roller mill according to any one of claims 1 to 9, wherein a lower portion of the contact surface is formed thick.