JP2018001056A - Vertical crusher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in which theoretical classification points are different between the upper and lower sides of a rotation-classifying blade by arranging a rotation classifying mechanism in a vertical crusher, when a casing shape is a truncated cone shape whose diameter reduces from the lower side to the upper side.SOLUTION: A stream dividing guide that extends downward from between a classifying mechanism and a casing is arranged, and an outer gas passage and an inner gas passage are formed in a crusher. A blowing-in part is formed on the upper side of the steam dividing guide, and the lower side is formed as an introduction part. The passage area of the outer peripheral gas passage and the inner peripheral gas passage is the same as that of the upper end and the lower end of the blow-in part and the lower end of the introduction part, and the height dimension of the blow-in part is in a range from 20% to 50% of the heigh dimension of the rotation classifying blade. Due to the structure, the present invention can divide gas bream, and blow it to the upper side and the lower side of the classifying mechanism uniformly, which can reduce effect on the shape of the casing, and change theoretical classification points uniformly.SELECTED DRAWING: Figure 1

Description

  The present invention mainly relates to a vertical pulverizer that pulverizes cement raw material, clinker, limestone, coal, biomass, and other inorganic raw materials, and more particularly to a suitable vertical pulverizer that finely pulverizes the raw material.

As an apparatus for efficiently pulverizing raw materials, a pulverizer called a vertical pulverizer (sometimes referred to as a vertical mill or a vertical roller mill) is used.
The vertical pulverizer has an excellent characteristic that it can efficiently pulverize a material to be crushed (sometimes simply referred to as a raw material in this specification).

The basic crushing behavior of the vertical crusher will be briefly described.
The vertical crusher has a crushing roller disposed on a rotary table, and the crushing roller is configured to be pressed in the direction of the rotary table. When the rotary table rotates, the crushing roller is driven and rotated via the raw material with respect to the rotary table.

The raw material charged into the vertical crusher is charged onto the rotary table via a chute for raw material charging, etc., is bitten by a pulverizing roller, and is pulverized. The raw material that is pulverized by being squeezed between the rotary table and the pulverizing roller travels to an annular gap between the outer peripheral portion of the rotary table and the casing.

  There are various types of vertical pulverizers. In the case of vertical pulverizers (sometimes called air-swept type), which are excellent for finely pulverizing and taking out raw materials, a rotary table is used. Gas is introduced from below, and an air flow of gas flowing from below to above is generated in the machine. Most of the raw material that has flowed into the above-described annular gap is blown up by the gas stream and travels upward in the machine. And the raw material used as the desired dimension is taken out with gas from the upper extraction port distribute | arranged above the turntable.

  The raw material that has not been pulverized to the desired size is not blown up by the gas and falls directly below the table, or even once blown up by the gas, it deviates from the gas flow before reaching the upper outlet. It is dropped and crushed again, such as by dropping on a rotating table. That is, when the raw material is finely pulverized, the raw material that could not be finely pulverized to a desired particle size by one pulverization is repeatedly pulverized in the machine.

  Here, conventionally, for the purpose of improving the classification efficiency, a vertical crusher provided with a classification mechanism in the upper part of the machine is often used. There are various classification mechanisms. As a typical classification mechanism, for example, a type that improves the efficiency of classification by arranging fixed classification blades in the machine and rectifies the air flow of gas flowing in the machine, and gas that flows in the machine by arranging rotary classification blades In general, there are known a type that improves the classification efficiency by strongly swirling the air flow, and a type that improves both the fixed classification blade and the rotary classification blade to improve the classification efficiency.

  In recent years, when pulverizing raw materials, a type of vertical crusher equipped with both stationary and rotary classification blades is often used as a vertical type crusher with excellent classification ability. It has become to. In the vertical crusher of the type having both the fixed type and the rotary type described above, a fixed classifying blade for rectification (sometimes referred to as a guide vane) is arranged on the outer peripheral side of the rotary type classifying blade. Cases that employ a classification mechanism are common. Patent Document 1 shows an example of a vertical crusher provided with a classification mechanism in which a rectifying fixed classification blade is arranged on the outer peripheral side of a rotary classification blade.

JP 2006-110521 A

Here, there is a case in which a classifier casing 201B having a shape shown in FIG. 7A is employed for the purpose of smoothly flowing a gas flow inside the vertical grinder.
In the classifier casing 201B shown in FIG. 7 (1), the shape of the classifier casing 201B on the outer peripheral side of the fixed classifying blade 214 is a truncated cone shape whose diameter is reduced upward, and in the vertical direction. The stationary classifying blade 214 that extends and the annular classifier blade 213 formed between the rotating classifying blade 213 and the classifier casing 201B are configured so as to become smaller from below to above.

  For example, when considering the gas flow when the top of the vertical crusher 201 is composed of a horizontal ceiling, the gas flow that collided with the ceiling becomes turbulent and rises from the lower side. The gas flow may be affected. In contrast, in the vertical pulverizer 201 having the configuration shown in FIG. 7A, the gas flow smoothly rises along the classifier casing 201B of the vertical pulverizer, and the rotary classification blade 213 Can flow into the side. As a result, the possibility of affecting the gas flow rising from the lower side is reduced. Therefore, the gas flow smoothly flows, and the pressure loss when the gas flow rises in the machine is reduced, so that efficient classification is possible.

  However, when the shape of the classifier casing 201B is a truncated cone shape whose diameter is reduced upward, the flow rate of the gas air flow is different between the upper and lower sides of the rotary classifying blade 213, and the upper part of the classifier casing 213 is above the rotary classifying blade 213. As a result, the tendency that the gas velocity in the center direction becomes faster tends to occur. In other words, a state occurs in which the flow rate of the gas air flow and the central direction speed are different between the upper and lower sides of the rotary classification blade 213.

Here, for reference, FIGS. 9A and 9B show the relationship between the direction of the gas flow in the classification mechanism 215 and the theoretical classification point d. Although details will be described later, the theoretical classification point d is the center direction speed Vg when the speed at which the gas stream flows toward the center in the machine is the center direction speed Vg (m / s) of the gas stream. Proportional to ^0.5 .

That is, when the state where the center direction speed Vg is different between the upper and lower sides of the rotary classification blade 213 occurs, the theoretical classification point d becomes different between the upper and lower sides of the rotary classification blade 213.
The classification mechanism 215 of the type shown in FIG. 7 (1) is a classification mechanism with excellent classification efficiency. However, in recent years, further improvement in classification efficiency has been demanded, and the theoretical classification point is located above and below the rotary classification blade. In order to solve the above-described problem of being in a different state, there has been a demand for the development of a vertical crusher equipped with a classification mechanism that solves the problem.

  The present invention has been made in view of the problems as described above, and includes a classifying mechanism that is suitable when the classifier casing has a truncated cone shape whose diameter is reduced from below to above. It relates to the technology of vertical crushers.

In order to achieve the above object, a vertical crusher according to the present invention comprises:
(1) A classification mechanism provided with a pulverizing roller and a rotary table, and pulverizing the raw material charged on the rotary table with a pulverizing roller and blowing it up with a gas supplied from below the rotary table, and arranging it above the rotary table. In a vertical crusher that takes out together with gas from the upper outlet, a fixed classifying blade in which a plurality of vertically extending plates are arranged in a ring at intervals, and a reverse fringe arranged at the lower end of the fixed classifying blade Arranging a classification mechanism comprising a conical inner cone and a rotary classification blade arranged in a ring with a plurality of plates extending in the vertical direction extending in the vertical direction on the inner peripheral side of the fixed classification blade, A frusto-conical shape in which the rotary classifying blade is provided so as to freely rotate on an annular swirling trajectory, and the shape of the classifier casing on the outer peripheral side of the fixed classifying blade is reduced in diameter upward In addition, a flow dividing guide extending downward from between the fixed classifying blade and the classifier casing is disposed, and a gap formed between the flow dividing guide and the classifier casing serves as an outer gas passage, and the fixed classifying blade Or the clearance gap formed between internal cones was made into the inner peripheral side gas channel.

(2) In the vertical crusher according to (1), the portion arranged at a position higher than the lower end position of the fixed classification blade of the flow dividing guide is used as a blowing portion, and the portion below the blowing portion of the flow dividing guide is introduced. As the part, the shape of the blowing part is a truncated cone shape whose diameter is reduced upward, and the height dimension of the blowing part is in the range of 20% or more to 50% or less of the height dimension of the rotary classifying blade. did.

(3) In the vertical crusher according to (2), the passage areas of the outer peripheral gas passage and the inner peripheral gas passage are the same at the upper and lower ends of the blowing portion and the lower end of the introducing portion.

(4) In the vertical crusher according to any one of (1) to (3), a straight line extending from the rotation center axis of the rotary classification blade and a straight line extending in the width direction of the rotary classification blade are provided. Regarding the inclination angle to be formed, the rotary classifying blade is formed by dividing it vertically, and the upper part of the rotary classifying blade is directed from the lower part to the inner peripheral side from the outer periphery side of the swirling orbit of the rotary classifying blade. Thus, it is formed so as to be largely inclined toward the rotation direction side of the rotary classification blade.

  In the present invention, by forming the outer peripheral side gas passage and the inner peripheral side gas passage by the diversion guide provided with the blowing portion and the introducing portion, the gas rising in the machine can be divided and blown to a desired location. There is an excellent effect of being able to.

  Further, if the height of the blowing part is in the range of 20% to 50% of the height of the rotary classifying blade, the rising gas is blown up and down the classifying mechanism, and the classifier casing. It is possible to reduce the influence of the gas flow velocity due to the reduced diameter.

  In particular, if the passage area of the outer peripheral side gas passage and the passage area of the inner peripheral side gas passage are the same at the upper and lower ends of the blowing portion and the lower end of the introduction portion, the rising gas is placed above and below the classification mechanism. It becomes possible to blow evenly.

  Further, the rotary classification blade is divided into a plurality of parts in the vertical direction, and the inclination angle is different at the upper and lower parts of the rotary classification blade. Therefore, the influence of the gas flow velocity due to the reduced diameter of the classifier casing can be reduced by the strength of the swirling flow due to the inclination angle of the rotary classifying blade. A more uniform classification is possible in the direction.

It is a figure explaining the whole structure of a vertical grinder concerning embodiment of this invention. It is a figure explaining the arrangement | positioning of the shunt guide and classification mechanism in connection with embodiment of this invention. It is a figure explaining the structure of the shunt guide according to the embodiment of the present invention. It is a figure explaining the external appearance of the shunt guide according to the embodiment of the present invention. It is a figure which conceptually demonstrates how the gas airflow flows in connection with the embodiment of the present invention. It is a figure explaining the inclination-angle of a rotary classification blade in connection with 2nd embodiment by this invention. It is a figure explaining the structure of the classification mechanism by the example of a prior art. It is a figure which illustrates notionally how to flow the gas airflow by the example of a prior art. It is a reference figure explaining a theoretical classification point. It is a reference figure explaining the influence on the direction of the airflow which the inclination of a rotary classification blade gives.

Hereinafter, an example of a preferred embodiment according to the present invention will be described in detail with reference to the drawings.
1 to 6 relate to the embodiment of the present invention and show preferred examples thereof.
FIG. 1 is a diagram illustrating the overall configuration of a vertical crusher. 2A and 2B are diagrams for explaining the arrangement of the diversion guide and the classification mechanism. FIG. 2A is a conceptual diagram observed from the side, and FIG. 2A is a diagram observed from the AA cross-sectional direction of FIG. FIG. 3 is a diagram illustrating the configuration of the diversion guide, and FIG. 4 is a diagram illustrating the appearance of the diversion guide. FIG. 5 is a diagram conceptually illustrating how the gas flow flows according to the embodiment of the present invention. FIG. 6 is a view for explaining the inclination angle of the rotary classifying blade in relation to the second embodiment according to the present invention, (2) is a view observed from the AA cross-sectional direction of (1), and (3) These are the figures observed from the BB cross-section direction of (1).

  FIG. 7 is a diagram for explaining the configuration of a classification mechanism according to an example of the prior art, and FIG. 8 is a diagram for conceptually explaining how the gas flow flows according to the example of the prior art. FIG. 9 is a reference diagram for explaining the theoretical classification point, and FIG. 10 is a reference diagram for explaining the influence of the inclination of the rotary classification blade on the direction of the airflow.

Hereinafter, an example of a preferable configuration of the vertical crusher 1 according to the present embodiment will be described with reference to FIGS. 1 to 5. The vertical crusher 1 shown in FIG. 1 is installed in a mill casing 1A, a classifier casing 1B, an outlet casing 1C that form an outer shell of the vertical crusher 1, and a lower portion of the vertical crusher 1. A reduction table 2B, a rotary table 2 driven by a drive motor (not shown), a conical crushing roller 3 and the like are provided.
The shape of the classifier casing 1B will be described. The upper part is a truncated cone shape whose diameter is reduced upward, and the lower part is a reverse truncated shape whose diameter is reduced downward. It is shaped like a hollow abacus ball.

  A vertical crusher 1 shown in FIG. 1 is a vertical crusher 1 of a type generally called a center chute type, and vertically downward from the upper part of the vertical crusher 1 toward the center of the rotary table 2. A raw material supply chute 35 is provided. The vertical crusher 1 is provided with an inverter power source (not shown) as a driving power source for the rotary table 2 and is a variable speed type in which the rotational speed of the rotary table 2 can be arbitrarily changed during operation.

Here, the vertical crusher 1 shown in FIG. 1 is a top-down type equipped with a classifier 15 inside. Above the turntable 2, an internal cone 19 having a substantially inverted truncated cone shape is provided, and a fixed classifying blade 14, which is a fixed primary classifying blade, is disposed above the inner cone 19. Yes. A rotary classification blade 13 is disposed above the internal cone 19 and inside the fixed classification blade 14.

A rotating cylinder 18 is disposed outside the raw material supply chute 35 of the vertical crusher 1 so that the raw material supply chute 35 is inserted. A classifier motor 20 is disposed on the top of the vertical crusher 1, and the rotary cylinder 18 and the classifier motor 20 are connected by a belt. The vertical crusher 1 shown in FIG. 1 has a configuration in which, when the classifier motor 20 is rotated, the rotary cylinder 18 connected by the belt rotates by the above-described configuration.

In the present embodiment, the rotary classification blade 13 is attached to the support member that extends radially from the rotary cylinder 18. Therefore, according to this embodiment, the classifying motor 20 is driven so that the rotary classifying blade 13 is freely rotated via the rotary cylinder 18. In this specification, the rotary classification blade 13 and the fixed classification blade 14 are collectively referred to as a classification mechanism 15.

  In addition, as shown in FIG. 1 or FIG. 2 etc., in this embodiment, the shape of the classifier casing 1B on the outer peripheral side of the fixed classifying blade 14 is a truncated cone shape whose diameter is reduced upward. An area of an annular passage (sometimes referred to as an annular passage) formed between the classifying blade 14 and the classifier casing 1B is formed so as to decrease from the lower side toward the upper side.

  Below the rotary table 2 of the vertical crusher 1, a gas inlet 33 for introducing gas and a discharge chute 34 (sometimes referred to as a lower outlet 34) for taking out a heavy material are provided. ing. Further, as described above, a raw material supply chute 35 for feeding the raw material into the machine is disposed above the turntable 2, and an upper portion for taking out a product (a raw material having a desired particle diameter after being pulverized) together with the gas. An outlet 39 is provided.

  The inner peripheral surface of the mill casing 1 </ b> A located at a position facing the outer peripheral portion of the rotary table 2 is cylindrical, and is annular between the outer peripheral portion of the rotary table 2 and the mill casing 1 </ b> A of the vertical crusher 1. A gap 30 (annular gap 30) is formed. Further, four crushing rollers 3 are arranged on the outer peripheral portion of the rotary table 2 so that the phase is shifted by 90 degrees.

Hereinafter, the configuration of the fixed classification blade 14 will be described.
As shown in FIGS. 2 (1) and (2), the fixed classifying blade 14 has a configuration in which a plurality of plates extending in the vertical direction are arranged in a ring at intervals. The upper end of the fixed classifier blade 14 and the classifier casing 1B are closed, and the gas flow rising along the classifier casing 1B is between the fixed classifier blades 14 arranged in a plurality. A shortcut is made without passing through the gap to prevent entry into the upper take-out port 39 side above the aircraft.

  In the present embodiment, as shown in FIG. 2B, the fixed classifying blade 14 has a width direction extending along a linear direction extending radially from the rotation center axis of the rotating classifying blade 13 described later. Is formed.

  The configuration of the fixed classifying blade 14 that can be applied to the present invention is not limited to the above-described configuration, and may be appropriately tilted as necessary. For example, the rectifying effect in the vertical crusher 1 can be increased to increase gas flow. For the purpose of smoothly flowing the air flow inside the machine, it is one of preferred configurations to incline from the outer peripheral side toward the inner peripheral side so as to go to the rotational direction side of the rotary classification blade 13.

Next, the structure of the rotary classification blade 13 in the vertical crusher 1 will be described.
As shown in FIGS. 2 (1) and (2), the rotary classifying blade 13 arranged on the inner peripheral side of the fixed classifying blade 14 has a plurality of vertically extending plates arranged in a ring at intervals. The arrangement is arranged. For the purpose of increasing the rigidity, the rotary classifying blade 13 is formed in an L shape or the like by bending the inner peripheral side portion as shown in FIG. The rotary classifying blade 13 is driven by a classifier motor 20 via a rotating cylinder 18 and the like, and is configured to freely rotate on a circular orbit formed in an annular shape.

  In addition, the structure of the rotary classification blade 13 in this invention is not restricted to the above-mentioned structure, The direct shape rotary classification blade 13 may be sufficient, and it is the shape bent as a whole. There is no particular limitation.

Hereinafter, the configuration of the diversion guide 10 will be described.
As shown in FIGS. 1 and 2, the diversion guide 10 according to the present embodiment has an upper end portion disposed between the fixed classifying blade 14 and the classifier casing 1B and extends downward.
The diversion guide 10 extending downward from the upper end portion is arranged so as to have a reverse truncated cone shape having an open lower end so as to surround the outer peripheral side surface of the inner cone 19 from the periphery.
FIG. 4 shows the appearance of the diversion guide 10. From the lower part of the classification mechanism 15, the inner cone 19 is covered and covered from the outside.

  Here, gaps are respectively formed between the diversion guide 10 and the inner cone 19 and between the diversion guide 10 and the classifier casing 1B, and an annular outer periphery is formed between the diversion guide 10 and the classifier casing 1B. A side gas passage 11 is formed, and an annular inner peripheral gas passage 12 is formed between the flow dividing guide 10 and the fixed classification blade 14 or the inner cone 19.

  In this embodiment, as shown in FIG. 1 or FIG. 3, the portion arranged at a position higher than the lower end position of the fixed classifying blade 14 is referred to as the blowing portion 10 </ b> A of the flow dividing guide 10, and the shape of the blowing portion 10 </ b> A is set upward. In addition to the truncated conical shape that decreases in diameter, the height dimension of the blowing part 10A (sometimes referred to as the blowing part height dimension Hg) is the height dimension of the rotary classifying blade 13 (rotating blade height dimension Hr). 35%).

  In addition, although mentioned later for details, about the relationship between the height dimension Hg of a blowing part, and the rotary blade height dimension Hr, the blow part height dimension Hg is the range of 20% or more to 50% or less of the rotary blade height dimension Hr. Then, it becomes a preferable configuration in that the rising gas can be blown up and down the classification mechanism 15.

  In the present embodiment, a portion below the blowing portion 10A of the diversion guide 10 is referred to as an introduction portion 10B. In the present embodiment, the passage area La of the outer peripheral gas passage 11 and the passage area Lb of the inner peripheral gas passage 12 are formed to be the same at the upper and lower ends of the blowing portion 10A and the lower end of the introducing portion 10B. did.

  Although details will be described later, the configuration in which the passage area La of the outer gas passage 11 and the passage area Lb of the inner gas passage 12 are the same at the upper end and lower end of the blowing portion 10A and the lower end of the introduction portion 10B is as follows. One of the preferred configurations is effective in approximating the amount of gas blown from between the blowing portion 10A and the fixed classifying blade 14 and the amount of gas blown from between the blowing portion 10A and the classification casing 1B.

Hereinafter, the crushing behavior of the vertical crusher 1 will be briefly described.
As described above, the vertical crusher 1 shown in FIG. 1 has the crushing roller 3 disposed on the rotary table 2, and each crushing roller 3 is configured to be pressed in the direction of the rotary table 2. ing. Then, the crushing roller 3 is driven to rotate via the raw material with respect to the rotary table 2 as the rotary table 2 rotates.

The raw material (the blast furnace slag in this embodiment) charged from the raw material supply chute 35 of the vertical crusher 1 is charged near the center of the rotary table 2 and draws a spiral trajectory. Move to the outer periphery. Then, the raw material moved to the outer peripheral side of the rotary table 2 is caught by the crushing roller 3 and crushed.

The raw material that is crushed by being squeezed between the rotary table 2 and the pulverizing roller 3 passes over the dam ring 5 that is provided around the outer edge of the rotary table 2 and between the outer peripheral part of the rotary table 2 and the mill casing 1A. It moves to the region of the formed annular gap 30. And the raw material which moved to the annular gap 30 is blown up by the gas and rises in the casing. At this time, the flow of the gas blown up is affected by the rotation of the rotary classifying blade 13 and becomes a swirling flow.

The raw material blown up in the swirling gas flows while swirling in the direction of the classification mechanism 15 disposed above the turntable 2. The raw material having a small diameter that has passed through the classification mechanism 15 is taken out as a product from the upper outlet 39.

Most of the raw materials that could not pass through the classification mechanism 15 fall inside the machine and are returned to the rotary table 2 and pulverized, or collected by the internal cone 19 and supplied again to the rotary table 2. And then crushed. On the other hand, an extremely heavy raw material is not blown up by the gas and falls downward of the turntable 2. The raw material dropped below the rotary table 2 reaches the bottom surface of the vertical crusher 1 and is taken out from the discharge chute 34 by a scraper (not shown) or the like.

Hereinafter, the function and effect of the classification mechanism 15 according to the present embodiment will be described.
The classifier performs a classification operation in which a group of particles having a particle size distribution is classified and sorted into a fine powder (product) and a coarse powder with a certain particle diameter as a boundary. The particle diameter serving as the boundary is generally called a theoretical classification point.

FIG. 9 is a diagram for explaining the classification function of the vertical crusher 1.
The theoretical classification point is expressed as Equation 1 below by arranging the equation of motion of the particles by the center direction velocity Vg between the blades and the turning direction velocity Vθ.

  d is the theoretical classification point (μm), Vθ is the velocity in the swirl direction of the airflow (m / s), and Vg (m / s) is the velocity in the airflow center direction.

  As described above, when the shape of the classifier casing 1B is a truncated conical shape whose diameter is reduced upward, the gas stream flows along the shape of the classifier casing 1B. There is a tendency for the amount of gas to increase above the blades 13 and at the same time, the velocity at which the gas flows in the central direction (the central velocity Vg of the airflow) increases.

  In the present embodiment, as shown in FIG. 5, the outer peripheral side gas passage 11 and the inner peripheral side gas passage 12 are formed by the diversion guide 10 provided with the blowing portion 10 </ b> A and the introducing portion 10 </ b> B. The coming gas can be divided by the introduction part 10B and blown from the blowing part 10A, and a desired amount of gas can be blown to the upper and lower parts of the classification mechanism 15.

  In the prior art, as shown in FIG. 8, the gas rising in the machine rises along the classifier casing 201 </ b> B, so that the flow rate and speed of the gas flow are greatly different above and below the rotary classifying blade 213. .

  In the present embodiment, the height dimension of the blowing part 10A is set to 35% of the height dimension of the rotary classifying blade 13 and mainly passes through the inner peripheral side gas passage 12 and the blowing part 10A and the fixed classifying blade 14 The gas blown out from the gap is selectively blown into the lower part of the rotary classification blade and flows, and the gas blown from between the blowing part 10A and the classification casing 1B through the outer peripheral passage 11 is blown into the upper part of the rotary classification blade 13 It was configured to flow in.

  The ratio of the height dimension of the blowing portion 10A to the height dimension of the rotary classifying blade 13 is influenced by the shape of the classifier casing 1B that is reduced in diameter upward, but the gas that has passed through the inner peripheral passage 12 In order to make the gas that flows into the lower part of the rotary classifying blade 13 and the gas that has passed through the outer peripheral passage 11 flow into the upper part of the rotary classifying blade 13, the blower height dimension Hg is set as shown in Equation 2 below. It is preferable that the rotational classification blade height dimension Hr be in the range of 20% to 50%.

  Further, in the present embodiment, in particular, with respect to the passage area La of the outer peripheral side gas passage 11 and the passage area Lb of the inner peripheral side gas passage 12, as shown in FIG. Part (passage area La3) and lower end (passage area La2), the lower end of the introduction part (passage area La1), and the upper end part (passage area Lb3) and lower end part (passage area) of the blowing part 10A in the inner gas passage 11 Lb2) and the lower end (passage area Lb1) of the introduction portion 10B are formed so that the following passage 3 is established as the same passage area.

  According to this embodiment, by dividing the interior of the machine by the introduction part 10B of the flow dividing guide 10, the amount of gas rising in the outer peripheral side gas passage 11 and the inner peripheral side gas passage 12 is adjusted, and the rotary classification blade 13 Can lead to the top and bottom and blow.

If the passage area La1 and the passage area Lb1 are made the same, the amount of gas rising in the outer peripheral side gas passage 11 and the inner peripheral side gas passage 12 can be made close to the same amount.
As a result, it is possible to adjust the flow rate of the gas air flow that has been largely different between the upper and lower parts of the rotary classification blade 13 in the direction close to the same flow rate, so that the classification ability that is different in the vertical direction of the rotary classification blade 13 is uniform. It becomes possible to approach the direction.

  Hereinafter, the second embodiment will be described as another example of a preferable configuration according to the present embodiment with reference to FIG. The vertical crusher 101 shown in FIG. 6 as the second embodiment is different from the above-described embodiment shown in FIG. 1 in the configuration of the classification mechanism 25, and is the same in other portions. In addition, about the vertical crusher 101, about codes other than the classification mechanism 25, it describes as the code | symbol same as the vertical crusher 1, and omits the description.

Hereinafter, the configuration and arrangement of the classification mechanism 25 different from the embodiment shown in FIG. 1 will be described. In the vertical pulverizer 101, the fixed classifying blade 24 has a configuration in which a plurality of plates extending in the vertical direction are arranged in a ring at intervals with the same manner as the vertical pulverizer 1 described above. The upper end of the fixed classifier blade 24 and the classifier casing 1B are closed, and a gas flow rising along the classifier casing 1B is formed between the fixed classifier blades 24 arranged in a plurality. A short cut is made without passing through the door, preventing entry to the upper outlet 39 side above the aircraft.

The rotary classifying blade 23 arranged on the inner peripheral side of the fixed classifying blade 24 has a configuration in which a plurality of plates extending in the vertical direction are arranged in a ring at intervals.
In the second embodiment, the rotary classifying blade 23 is formed by dividing a vertically extending plate into two in the vertical direction, the upper blade is the rotary classifying blade 23A, and the lower blade is rotated. It was set as formula classification blade 23B. The rotary classifying blades 23A and 23B are driven by the classifier motor 20 via the rotary cylinder 18 and the like, and freely rotate on the circular orbit formed in the orbit.

  Here, the inclination angle α formed by the straight line extending from the rotation center axis of the rotary classifying blade 23 and the straight line extending in the width direction of the rotary classifying blade 23 will be described. The rotary type blades 23 are inclined toward the inner circumferential side toward the rotational direction side (R direction) of the rotary classifying blade 23 and the above-mentioned tilt angles are made different at the upper and lower parts of the rotary type classifying blade 23 so that the rotary type is located at the lower part. The rotary classifying blades 23A on the upper side of the classifying blades 23B are formed so as to be inclined so that the inclination angle becomes large.

  In the present embodiment, as shown in FIGS. 6 (1) to (3), the inclination angle α1 of the rotary classification blade 23A is set to the inclination angle α2 of the rotary classification blade 23B in the lower portion, and An inclination angle of a certain rotary classification blade 23A is formed larger than that of the rotary classification blade 23B in the lower part, and α1> α2. In the second embodiment, α1 is 30 degrees and α2 is 0 degrees.

  In this embodiment, as shown in FIG. 6, the rotary classification blade 23 has a shape in which the width direction extends linearly. However, for the purpose of increasing the rigidity of the rotary classifying blade 23, for example, it is preferable to bend partly into an L shape or the like, and the inclination angle α in this case is set with reference to a long part in the width direction. Just do it.

  Further, in order to increase the rigidity of the rotary classifying blade 23, when the rotary classifying blade 23 is slightly bent as a whole, the inclination angle α may be set with reference to a straight line connecting both ends in the width direction.

Hereinafter, the effect of the classifying mechanism 25 of the vertical crusher 101 shown in FIG. 6 will be described.
As described above, when the shape of the classifier casing 1B is a truncated conical shape whose diameter is reduced upward, the gas stream flows along the shape of the classifier casing 1B. There is a tendency that the gas velocity Vg in the center direction becomes faster as it goes above the blade 13.

  FIG. 9 (1) conceptually shows the direction of airflow by the rotary classification blade 213 according to the example of the prior art. As the rotary classification blade 213 rotates, the swirl direction velocity Vθ of the airflow increases. However, when the rotary classifying blade 213 is the same in the vertical direction, the rotational speed Vθ is the same in the vertical direction of the rotary classifying blade 213. Therefore, if the center direction speed Vg is different in the vertical direction of the rotary classification blade 213, the theoretical classification point d may be different, which may be an obstacle to improving the classification efficiency.

  In the present embodiment, the rotary classification blade 23 is divided into two in the vertical direction, and the inclination angle α is made different between the upper and lower portions of the rotary classification blade 23. The inclination angle α1 of the rotary classification blade 23A is formed larger than the inclination angle α2 of the rotary classification blade 23B.

  In view of Equation 1 described above, when the center direction speed Vg in the numerator is large, the turning direction speed Vθ in the denominator is increased, and when the center direction speed Vg in the numerator is small, the turning direction speed Vθ in the denominator. It is assumed that it is preferable to reduce

  However, as a result of diligent research, the present applicant has newly generated an airflow in the apparatus that opposes the flow of the gas flowing up along the classifier casing 1B, so that the upper and lower portions of the rotary classifier blade 23 It has been found that the difference between different theoretical classification points d can be relaxed.

  That is, in the second embodiment, the flow rate of the gas airflow flowing up and down the rotary classifying blade 23 is adjusted by the flow dividing guide 10, and the rotary classifying blade 23A The direction of the airflow is changed by changing the inclination angle α of the rotary classification blade 23B.

  When the rotary classifying blade 23 is tilted at the tilt angle α, the swirl direction velocity Vθ of the gas stream changes as shown in FIG. 10 (2), and at the same time, the flow of gas from the inner periphery side to the outer periphery side of the swirl track is changed. This occurs as an anti-center direction velocity Vg2.

  And the flow of the airflow which is going from the inner peripheral side to the outer peripheral side of the turning track of the rotary classifying blade 23 is opposed to the flow of the airflow rising along the classifier casing 1B. The speed Vg2 decelerates the center direction speed Vg. As a result, the difference in the theoretical classification point d that is different between the upper and lower portions of the rotary classification blade 23 can be reduced.

  When the inclination angle α is described, the maximum is 45 degrees. If it is larger than that, the effect of strengthening the swirling flow is weakened.

  Note that it is particularly preferable to form the rotary classifying blades 23 equally in three or four in terms of alleviating the difference in the theoretical classification point d.

  According to the second embodiment, the flow dividing guide 10 reduces the influence of the flow rate of the different gas flows above and below the rotary classification blade 23, and further influences the velocity of the gas flow rate on the inclination of the rotary classification blade. By relaxing by the difference, further uniform classification in the vertical direction of the rotary classification blade 23 becomes possible.

  As described above, the technique according to the present invention is useful for improving the crushing efficiency of a vertical crusher having a classifier casing having a truncated cone shape whose diameter is reduced upward and can be suitably used.

DESCRIPTION OF SYMBOLS 1 Vertical crusher 1A Mill casing 1B Classifier casing 1C Outlet casing 2 Rotating table 2B Reduction gear 3 Crushing roller 5 Dam ring 10 Dividing guide 10A Blowing part 10B Introduction part 11 Outer peripheral side gas passage 12 Inner peripheral side gas passage 13 Rotation Type classifying blade 14 Fixed type classifying blade 15 Classifying mechanism 18 Rotating cylinder 19 Internal cone 20 Classifier motor 23 Rotating type classifying blade (second embodiment)
23A Rotary classification blade (upper part)
23B Rotary classification blade (bottom)
24 fixed classification blades (second embodiment)
25 classification mechanism (second embodiment)
30 Annular gap 33 Gas inlet
34 Discharge chute 35 Raw material supply chute 39 Upper outlet 101 Vertical crusher (second embodiment)

Claims (4)

A crushing roller and a rotary table are provided, and the raw material put on the rotary table is pulverized by the crushing roller, and blown up by the gas supplied from below the rotary table, and the upper part through a classification mechanism arranged above the rotary table. In a vertical crusher that takes out gas from the outlet,
Fixed classifying blades arranged in a ring with a plurality of plates extending in the vertical direction arranged at intervals, an inverted cone-shaped internal cone arranged at the lower end of the fixed classifying blades, and the inner circumference of the fixed classifying blades A classifying mechanism having a rotary classifying blade arranged in a ring shape with a plurality of plates extending in the vertical direction at an interval is arranged on the side so that the rotary classifying blade can freely rotate on an annular swirling trajectory In addition, the shape of the classifier casing on the outer peripheral side of the fixed classifying blade is a truncated cone shape whose diameter is reduced upward,
In addition, a diversion guide extending downward from between the fixed classifier blade and the classifier casing is arranged, and a gap formed between the diversion guide and the classifier casing serves as an outer gas passage, and the fixed classifier vane or the inside A vertical crusher with a gap formed between the cone and the gas passage inside. While using the portion arranged at a position higher than the lower end position of the fixed classification blade of the diversion guide as the blowing portion, the lower portion from the blowing portion of the diversion guide as the introduction portion,
The shape of the blowing portion is a truncated conical shape whose diameter is reduced upward, and the height of the blowing portion is set in a range of 20% to 50% of the height of the rotary classification blade. The vertical crusher according to claim 1, wherein the vertical crusher is characterized.   The vertical crusher according to claim 2, wherein passage areas of the outer peripheral gas passage and the inner peripheral gas passage are the same at the upper and lower ends of the blowing portion and the lower end of the introducing portion. About the inclination angle formed by the straight line extending from the rotation center axis of the rotary classifying blade and the straight line extending in the width direction of the rotary classifying blade,
The rotary classifying blade is formed by dividing the vertical classifying blade in the vertical direction. The upper part of the rotary classifying blade is lower than the lower part of the swirling track of the rotary classifying blade from the outer peripheral side to the inner peripheral side. The vertical crusher according to any one of claims 1 to 3, wherein the vertical crusher is formed so as to be largely inclined toward a rotation direction side.

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