WO2019031294A1

WO2019031294A1 - Vertical pulverizer

Info

Publication number: WO2019031294A1
Application number: PCT/JP2018/028517
Authority: WO
Inventors: 竜也日名内; 泰文中尾
Original assignee: 宇部興産機械株式会社
Priority date: 2017-08-09
Filing date: 2018-07-31
Publication date: 2019-02-14
Also published as: JPWO2019031294A1; JP7131556B2

Abstract

Provided is a vertical pulverizer provided with a rotating table, a pulverizing roller that rotates on the rotating table for pulverizing raw material supplied between the same and the rotating table, a gas introduction opening for introducing gas that blows off pulverized bodies formed from the raw material that has been pulverized, a separator provided above the rotating table and having a rotating part for classifying the pulverized bodies blown off by the gas introduced through the gas introduction opening, and an upper casing for accommodating the separator and having a product extraction opening for extracting the classified pulverized bodies to the outside, wherein an eccentric plate forming an eccentric opening that is eccentric with respect to a rotating center axis for the separator is provided below the product extraction opening and above the separator in the upper casing.

Description

Vertical crusher

The present invention relates to a vertical crusher for crushing coal, oil coke, limestone, blast furnace slag, electric furnace slag, cement clinker, cement raw material, chemicals or the like as a raw material, and particularly a vertical type capable of highly efficient classification and crushing. It relates to a crusher.

Conventionally, vertical crushers for crushing coal, oil coke and the like have been widely used, and in recent years there has also been an increasing demand for using fine powders obtained by finely pulverizing raw materials by vertical crushers as products. Such a vertical crusher has a classification mechanism inside, and is configured to be able to take out fine powder of a desired particle size as a product (for example, see Patent Documents 1 and 2). .

As a vertical crusher equipped with such a classification mechanism, the one disclosed in Patent Document 1 in particular conveys the crushed raw material as powder by the air flow blown from the lower housing (lower casing) of the crusher. Raise it. At the same time, only a fine powder having a desired particle size is selected from among the powder transported by the air flow by the classification mechanism disposed in the upper housing (upper casing) in the vertical mill.

Then, the selected fine powder is taken out from the product outlet of the upper housing as a product to the outside of the machine, whereby a product consisting of the fine powder is manufactured. Generally, as such a classification mechanism, for example, a separator which is disposed above a rotary table and has a plurality of rotary blades as a rotary unit is known.

JP, 2013-193041, A JP, 2016-131909, A

In the separator, the powder particle group having a particle size distribution is classified into a product (fine powder) and a non-product (coarse powder) at a desired particle diameter. The particle diameter which becomes this boundary is called "theoretical classification point", and it is considered as ideal classification that it is uniform in the height direction and the circumferential direction of the rotating part of the separator.

The theoretical classification point can be obtained by arranging the equation of motion of the particles of the powder, for example, by the central velocity between the rotating blades of the separator and the rotational velocity. However, while the rotation speed of the rotating blades actually forms a substantially uniform swirling velocity field, since the central velocity is not uniform in the circumferential direction, the theoretical classification point is biased particularly in the circumferential direction. It will occur.

The deviation of the central velocity is called drift and has been found to be mainly caused by the relationship between the arrangement of the product outlet and the rotational direction of the rotating part of the separator. As described above, when the theoretical classification point is deviated in the circumferential direction, the particle size width of the particle size distribution of the product increases so as to have a wider particle size configuration than what is originally desired to be obtained. This may adversely affect the quality of the product.

In addition, it is also known that the deviation of theoretical classification points causes the performance reduction of a vertical mill. That is, the fine powder to be originally sorted and recovered as a product is returned to the vertical mill as a coarse powder at a location in the circumferential direction. And, the extra energy consumption increases to handle the returned powder, which not only causes the reduction of the grinding amount but also causes the increase of the power consumption.

Furthermore, if the amount of powder returned into the vertical crusher increases, the amount of powder on the rotary table may increase, which may cause vibration of the crusher. In order to suppress such vibration, the operation of the vertical crusher has to be stopped, and the loss per operation unit becomes large.

Further, in the technique disclosed in Patent Document 2, the upper case of the separator having the product outlet is formed to be eccentrically arranged from the rotation center axis of the separator. With this configuration, the technology disclosed in Patent Document 2 can reduce the deviation of the theoretical classification points of the separator having the rotating portion, and as a result, the power consumption rate can be improved, the amount of crushing increased, and the vibration reduced. Excellent operational effects such as can be expected.

In the case where the technology disclosed in Patent Document 2 is adopted for a vertical mill, the expected effects and the like are shown in FIGS. 7 and 8 for reference. 7 and 8 show, in plan view, a portion corresponding to the AA cross section and the BB cross section in FIG. 2 described later of the reference example and the comparative example disclosed in Patent Document 2, respectively. FIG. 10 is a distribution diagram of theoretical classification points in the circumferential direction of the case. An analysis of the case where the upper case is eccentrically arranged from the rotation center axis of the separator (reference example) shows that the deviation of the theoretical classification point can be expected to be smaller compared to the case where the eccentricity is not made (comparative example) Became.

However, the technique disclosed in Patent Document 2 requires the upper case of the vertical mill to be disposed eccentrically from the central axis of rotation of the separator. In the case of newly installing a vertical crusher, eccentricity of the upper case is relatively easy. However, in the case of remodeling the existing equipment, the upper case itself needs to be reworked, which requires a considerably large modification. Therefore, a technique that can reduce the deviation of the theoretical classification points described above by a simple method has been required.

The present invention solves the problems of the prior art described above, and makes it possible to reduce the deviation of theoretical classification points of the separator having the rotating part as much as possible with a simple configuration and increase the amount of grinding while improving the power consumption. It is an object of the present invention to provide a cost-effective vertical mill capable of improving the quality of fine powder products while reducing vibrations.

The vertical crusher according to the present invention comprises a rotary table, a grinding roller that rotates on the rotary table and that grinds the raw material supplied on the rotary table between the rotary table, and the ground raw material from the ground raw material A gas inlet port for introducing a gas for blowing up powder particles, a separator having a rotating portion provided above the rotary table and classifying the powder particles blown up by the gas introduced from the gas inlet port; And an upper casing having a product outlet for containing the separator and taking out the classified powder particles to the outside, wherein the upper casing is provided above the separator and on the product outlet. An eccentric plate is formed below the lower plate to form an eccentric opening eccentric to the central axis of rotation of the separator.

In one embodiment of the present invention, the separator has a circular opening at the top, and the eccentric plate is disposed in the inner region of the opening along the opening when viewed from above from above And a crescent-shaped plate member.

In another embodiment of the present invention, the eccentric plate uses the central axis of rotation of the rotating portion of the separator as an origin, and the upper casing is disposed on the left side with the product outlet in plan view from above In the orthogonal coordinate system, when the rotating part of the separator rotates clockwise, the center point of the eccentric opening is located in the fourth quadrant, and when the rotating part of the separator rotates counterclockwise, the eccentric opening The center point of is formed so as to be located in the first quadrant.

In still another embodiment of the present invention, in the eccentric plate, the rotating portion of the separator is circular, the outer diameter thereof is D, and X from the origin of the center point of the eccentric opening in the orthogonal coordinate system When the distance in the direction is SX and the distance in the Y direction is SY, the distance between SX and SY is (a) 0.015 × D ≦ SX ≦ 0.080 × D [mm], (b) 0.015 It is provided so as to satisfy the condition of × D ≦ SY ≦ 0.080 × D [mm].

In still another embodiment of the present invention, the upper casing is disposed above the separator and below the product outlet along the outer periphery of the separator from the separator of the gas to the product outlet A short path prevention plate is provided to prevent a short path, and the eccentric plate is integrally provided on the short path prevention plate.

According to the present invention, the deviation of the theoretical classification point of the separator having the rotating portion is made as small as possible with a simple configuration, and the pulverizing amount is increased while improving the power consumption, thereby reducing the vibration while reducing the vibration. It is possible to provide a cost-effective vertical crusher capable of improving product quality.

BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the whole structure of the vertical mill which concerns on one Embodiment of this invention. It is a partially enlarged view of the same bowl type crusher. It is explanatory drawing which shows the state which saw the partial horizontal cross section of the vertical grinder of FIG. 2 from the top by planar view. FIG. 3 is a cross-sectional view taken along the line CC of FIG. 2; It is explanatory drawing which shows the state which saw the partial horizontal cross section in case the rotation part of the separator of the vertical mill of FIG. 2 rotates counterclockwise, and was planarly viewed from upper direction. It is explanatory drawing which shows the state which saw the partial horizontal cross section of the vertical mill which is a comparative example from upper direction by planar view. FIG. 7 is a distribution diagram of theoretical classification points in the circumferential direction when a portion corresponding to the AA cross section in FIG. 2 of the reference example and the comparative example disclosed in Patent Document 2 is viewed from above in plan view. FIG. 8 is a distribution diagram of theoretical classification points in the circumferential direction when a portion corresponding to the BB cross section in FIG. 2 of the reference example and the comparative example disclosed in Patent Document 2 is viewed from above in plan view.

Hereinafter, a vertical crusher according to an embodiment of the present invention will be described in detail with reference to the attached drawings. However, the following embodiment does not limit the invention according to each claim, and all combinations of the features described in the embodiments are essential to the solution means of the invention. Not exclusively.

As shown in FIGS. 1 to 3, the vertical crusher 1 according to this embodiment includes, as a power source, for example, a rotary table motor 2 provided on the side of the reduction gear 4 and an upper casing 20 described later. A rotor motor 3 provided in the vicinity of the upper case 21 is provided. The reduction gear 4 decelerates the rotational force from the rotary table motor 2 and transmits it to the rotary table 5.

Further, the vertical crusher 1 is disposed on the reduction gear 4 and rotated by the rotation table motor 2 via the reduction gear 4, and the rotation table 5 is rotated on the rotation table 5. A plurality of pulverizing rollers 8 which can be driven to roll, and a separator 30 having a rotating rotor 31 which is a rotating portion as a classification mechanism disposed above the rotating table 5 are provided. The rotor motor 3 rotationally drives the rotary rotor 31 of the separator 30. In addition, although the separator 30 of this embodiment is comprised including the rotary rotor 31 and the fixed blade | wing 32 which are rotation parts, what does not have the fixed blade | wing 32 but separator itself rotates can also be employ | adopted.

The vertical crusher 1 includes a control device 18 that controls the operation of the rotary table motor and the

rotor motors

2 and 3. The control device 18 freely controls the rotational speed and the rotational speed of the rotary table 5 and the rotary rotor 31 by controlling the operations of the rotary table motor and the

rotor motors

2 and 3. Further, the vertical crusher 1 is provided with a casing 10 that accommodates the above-described components other than the rotary table motor and the

rotor motors

2 and 3 inside.

The casing 10 is installed, for example, on the installation table 10a, and in the height direction of the vertical crusher 1, for example, a lower casing 19 that accommodates from the lower end of the reduction gear 4 to the lower end of the separator 30, It comprises the upper casing 20 which covers the upper part of the mold crusher 1.

The lower casing 19 is formed, for example, such that a predetermined portion in the height direction from the side of the rotary table 5 to the lower side of the separator 30 has a cylindrical shape. The upper casing 20 includes, for example, a lower case 22 which covers and accommodates the side from the lower end to the upper end of the separator 30, and an upper case 21 which covers the upper side of the separator 30, and has a product outlet 29.

The upper casing 20 extends slightly to the upper inside of the upper end of the rotary rotor 31 of the separator 30 at the inner side near the boundary 21 a between the upper case 21 and the lower case 22 and is located below the product outlet 29. And a seal plate 41 formed to extend slightly downward from the short path prevention plate 40 to the side of the rotary rotor 31. As shown in FIG.

The short path prevention plate 40 suppresses the flow of air from the separator 30 directed from the lower case 22 toward the upper case 21 to the product outlet 29 and the short path flow. The short path prevention plate 40 has a structure in which an eccentric plate 49 (see FIG. 4) is integrally provided, for example, so as to have a function of an eccentric plate described later in the present embodiment. The extended front end surface of the short path prevention plate 40 (peripheral wall surface of the opening, hereinafter referred to as "end surface") 40a and the end surface on the opening side of the eccentric plate 49 (hereinafter referred to as "end surface") 49a. Forming a continuous opening inner peripheral wall surface of a circular eccentric opening 47 described later.

The lower case 22 is formed, for example, in a truncated cone shape. The lower case 22 may have various other shapes such as a polygonal frustum shape and an elliptical frustum shape. The upper case 21 has a duct portion 21b leading to a product outlet 29 provided to project upward or sideward, and has, for example, one product outlet 29 opened to the side. For example, a straightening vane (not shown) may be attached to the inside of the duct portion 21b.

In the present embodiment, the duct portion 21b of the upper case 21 is included in the upper casing 20, but the duct portion 21b is configured separately and connected to the side surface of the upper case 21 and the like. May be Further, as shown in FIG. 3, the centers P1 of the lower case 22 and the upper case 21 coincide with, for example, the rotation center axis P2 of the rotating rotor 31 of the separator 30 in the axial direction.

As shown in FIG. 4, the short-pass preventing plate 40 inherently forms a circular opening 48 above the region slightly inside the upper end of the rotary rotor 31 of the separator 30 by the end face 40a. is there. The eccentric plate 49 integrally provided so as to be continuous with a part of the end face 40a of the short path prevention plate 40 has the lower case 22 and the upper case by the end face 49a continuous with the end face 40a. The eccentric opening 47 is made eccentric to the center P1 of 21 and the rotation center axis P2 of the separator 30.

Here, the eccentric plate 49 has a function to suppress air flow entrainment and short path flow as well as the short path prevention plate 40, and is essentially circular provided above the rotary rotor 31 as viewed from above from above. It is formed of a plate-like member made of a metal, a heat-resistant resin or the like formed in a crescent shape disposed in the inner region of the opening 48.

The eccentric plate 49 is disposed planarly and integrally with the short path prevention plate 40 by processing such as bolting and welding. In addition, for example, the eccentric plate 49 may be installed separately from the short path prevention plate 40. In such a case, the eccentric plate 49 is attached to the lower case 22 or the upper case 21 in the vicinity of the boundary 21a via a bracket or the like (not shown) or, for example, in the vertical direction in the vicinity of the boundary 21a It may be provided in a state of being placed and adhesively fixed so as to form the eccentric opening 47 while overlapping.

The opening portion 48 of the short path prevention plate 40 is arranged such that the center point P3 of the eccentric opening 47 is eccentrically arranged from the center P1 of the lower and

upper cases

22 and 21 and the rotation center axis P2 of the rotary rotor 31 of the separator 30. And an eccentric plate 49 formed on the inner side near the boundary 21 a.

More specifically, the eccentric plate 49 has a rotation center axis P2 of the rotation rotor 31 of the separator 30 as an origin, and orthogonal coordinates when the upper casing 20 is disposed on the left side with the product outlet 29 in plan view from above In the system, when the rotary rotor 31 of the separator 30 rotates clockwise as indicated by the arrow in the drawing, the center point P3 of the eccentric opening 47 is located in the fourth quadrant, for example, as shown in FIG. When the rotary rotor 31 of the separator 30 rotates counterclockwise as indicated by the arrow in the drawing in the counterclockwise direction, the center point P3 of the eccentric opening 47 is formed in the first quadrant although not shown. As described above, the state in the first to third quadrants (a part may be in the fourth quadrant) or the state in the second to the fourth quadrants (a part may be in the first quadrant) In the crescent shape That. The eccentric opening 47 is formed so that its center point P3 is also eccentric to the centers P1 of the lower case 22 and the upper case 21 in other words.

More specifically, for example, the rotating rotor 31 of the separator 30 has a cylindrical shape, and the outer diameter of the eccentric plate 49 is D (see FIG. 2). When the dimension in the X direction from the origin (rotational center axis P2) of the central point P3 of S is the dimension in the SX and Y directions as SY (see FIG. 4), the following conditions (a) and (b) are satisfied Preferably, the eccentric opening 47 is provided.
(A) 0.015 × D ≦ SX ≦ 0.080 × D [mm]
(B) 0.015 × D ≦ SY ≦ 0.080 × D [mm]
If SX, SY is smaller than 0.015 D, the effect of eccentricity may be too small. When the degree of eccentricity is larger than 0.080 D, there is a possibility that the eccentric plate 49 can not be installed in the upper casing 20 due to a structural problem. In the present embodiment, the eccentric plate 49 is provided under the condition that the dimension is SX = SY = 0.032D.

That is, the eccentric plate 49 is located in such a position that the eccentric opening 47 is formed eccentrically in the X direction in the direction of the anti-product outlet 29 in the X direction, and in the Y direction as viewed from above. When viewed from the product outlet 29, when the rotary rotor 31 rotates clockwise, the rotor 31 is eccentric rightward (see FIG. 3), and when the rotor 31 rotates counterclockwise, the product outlet 29 When viewed from the side, it is provided at a position where it is formed eccentrically in the left direction (see FIG. 5).

The eccentricity of the eccentric opening 47 in the X direction by the eccentric plate 49 as described above makes it possible to suppress the short path flow immediately below the product outlet 29 and the duct portion 21b. Further, the eccentricity of the eccentric plate 47 in the Y direction of the eccentric opening 47 can suppress the air flow wrap around the rotation of the rotary rotor 31. Then, the gas flow from the separator 30 to the product outlet 29 can be made more straight and less drift like the air flow F3 shown in FIG.

Thus, the center point P3 of the eccentric opening 47 is eccentrically arranged from the centers P1 of the lower and

upper cases

22 and 21 and the rotation center axis P2 of the rotary rotor 31 of the separator 30, thereby a theoretical classification point of the separator 30 described later. It becomes possible to suppress the bias of d. Along with this, it is possible to improve the power consumption rate of the vertical pulverizer 1 and to increase the amount of pulverization to improve the quality of the fine powder product while reducing the vibration.

Further, it is possible to suppress the deviation of the theoretical classification point d with a simple structure in which the eccentric plate 49 is merely disposed between the lower case 22 and the upper case 21 without largely changing the structure of the upper casing 20. It is possible to increase cost merit by achieving commonality of the upper casing 20 and the like.
When it is desired to change the degree of eccentricity as a result of the operation described later, the degree of eccentricity can be easily adjusted by replacing the eccentric plate 49 or additionally installing it.

On the other hand, the rotary table 5 shown in partial cross section in FIG. 1 is configured to include a circular central region 5a and an annular roller rolling region 5b around it. Above the central region 5a of the rotary table 5, a cylindrical chute 6 extending vertically from the top of the vertical crusher 1 toward the center of the rotary table 5 is provided. New material (cement clinker etc.) is supplied to the chute 6 from above.

The outer peripheral side of the chute 6 is provided with a funnel-shaped cone 7 for supplying the internal circulation raw material (particulate matter). The lower ends of the chute 6 and the cone 7 are arranged, for example, to form the same plane. Therefore, the new raw material and the internally recycled raw material are stably fed and supplied onto the central region 5 a of the rotary table 5 through the chute 6 and the cone 7. Each raw material supplied onto the central area 5 a of the rotary table 5 is guided to the roller rolling area 5 b by the rotational force of the rotary table 5.

Further, the vertical crusher 1 includes, for example, a plurality of crushing rollers 8 capable of rolling following the rotation of the rotary table 5 on the roller rolling area 5b of the rotary table 5, and a plurality of auxiliary rollers not shown. ing. The grinding roller 8 is disposed, for example, at a position which bisects the roller rolling area 5b in the circumferential direction, and the auxiliary roller is a position between the grinding rollers 8 which bisects the roller rolling area in the circumferential direction Is located in

The grinding roller 8 is connected to, for example, the piston rod 11A of the hydraulic cylinder 11 via the

arms

9, 9A of the pressure device attached to the lower casing 19 in a pivotable manner by a shaft. By operating the hydraulic cylinder 11 of the pressing device, the pulverizing roller 8 is pressed against the roller rolling area 5b of the rotary table 5 to apply a pulverizing force to the raw material layer.

The auxiliary roller may also be swingably supported in the same configuration. The grinding roller 8 mainly pulverizes the raw material, and the auxiliary roller is mainly used to degas the raw material layer. Each raw material supplied on the central area 5a of the rotary table 5 and supplied to the roller rolling area 5b and passed between the rotary table 5 and the grinding roller 8 and the auxiliary roller in the roller rolling area 5b is a rotary table. It is blocked by a dam ring 12 circumferentially provided on the outer peripheral edge portion of 5. For example, the height of the dam ring 12 is adjustable.

An annular passage 13 is formed between the outer peripheral portion of the rotary table 5 and the lower casing 19 to serve as a gas blow-up portion. The lower casing 19 is provided with a gas introduction duct 14 for introducing gas into the annular passage 13 from an exhaust fan provided outside. Further, the lower casing 19 is provided with a lower extraction duct 15 for taking out the raw material which has not been sufficiently crushed and has fallen into the annular passage 13.

In the lower case 22 of the upper casing 20, a separator 30 is disposed in the inner region of the cone 7 so as to surround the chute 6. The separator 30 is a raw material pulverized by the rotary table 5 and the pulverizing roller 8 by rotating the rotary rotor 31 having rotary blades by the rotor motor 3 and the belt 3a together with the rotary cylinder 3b rotated by belt drive, for example ( The powder is classified into a product (fine powder) of a predetermined particle size. In addition, fixed blades 32 are provided at corresponding positions on the outer peripheral side of the rotary rotor 31 of the separator 30 at the upper part of the cone 7, that is, at positions slightly away from the rotary rotor 31.

Then, from the product outlet 29 provided in the upper case 21 of the upper casing 20, a sufficiently pulverized fine powder which has been blown up by the gas flow and passed through the separator 30 (fixed blade 32 and rotating rotor 31) is a product Taken out. Specifically, the vertical mill 1 configured in this way operates, for example, as follows.

First, the new raw material is supplied from the chute 6 onto the central region 5 a of the rotary table 5 while the rotary table 5 is rotated. The supplied new raw material receives centrifugal force in the radial direction of the table by the rotation of the rotary table 5 and moves on the rotary table 5 while sliding in the outer peripheral direction. During movement, the raw material receives a force in the rotational direction by the rotary table 5 and slides between the raw material and the rotary table 5 to rotate at a speed somewhat slower than the rotational speed of the rotary table 5.

As described above, the raw material acts on the raw material in a spiral trajectory on the rotary table 5 by applying a force in which the two forces in the radial direction and the rotational direction of the rotary table 5 are combined. It is led to the motion area 5b. The raw material thus introduced to the roller rolling area 5b enters between the grinding roller 8 and the auxiliary roller and the rotary table 5 from a direction forming an angle with the roller axial direction. Thus, it is bitten, deaerated and crushed, and blocked by the dam ring 12.

On the other hand, gas such as air or hot air from the gas introduction duct 14 blows up from the annular passage 13 into the lower casing 19. Among the raw materials (powders and grains) which go over the dam ring 12 after grinding, the raw materials which are scattered during the grinding and float in the machine, or the internally circulating raw materials (powders and grains), those whose particle diameter is not particularly large It rides on the gas stream and blows up.

The raw material blown up is entrained by the gas and ascends in the lower casing 19 and is classified by the fixed blades 32 and the rotary rotor 31 of the separator 30 located in the upper casing 20. As a result, the one having a predetermined particle size (fine powder) is discharged as a product from the product outlet 29 together with the gas. At the same time, the coarse powder particles fall again on the rotary table 5 through the cone 7 as an internal circulation material and are crushed.

Also, among the raw materials that have passed over the dam ring 12, for example, those with extremely large particle diameter, extremely heavy ones including metals, etc., fall from the annular passage 13 to the lower side of the vertical crusher 1, It is taken out from the takeout duct 15 to the outside. The taken-out raw material is returned again to the chute 6 from the transfer line (not shown) as necessary, and is crushed in the vertical mill 1 by external circulation.

The present applicant has obtained the following findings as a result of intensive studies to enhance cost merits while attempting to improve classification efficiency with a simple configuration in the vertical mill 1 that operates in this manner. First, an essential simulation fluid analysis was performed on the classification points of the separator 30. Thereby, it was found that the deviation of the theoretical classification point d becomes remarkable in the circumferential direction of the separator 30. By suppressing this bias, the classification efficiency of the separator 30 can be improved. Hereinafter, the fluid analysis result of the example of the vertical grinder 1 of this embodiment and the conventional vertical grinder (comparative example) is compared and demonstrated. FIG. 6 is a top view of the vertical mill of the comparative example. In FIG. 6, the same components as those of the above-described embodiment (FIGS. 1 to 5) are denoted by the same reference numerals, and the description thereof will not be repeated.

First, a comparative example will be described. As shown in FIG. 6, in the vertical crusher of the comparative example, both the lower case 22 and the upper case 21 of the upper casing are formed in a truncated cone shape that is concentric. Accordingly, the centers P1 of the lower and

upper cases

22 and 21 as shown in FIG. 6 and the central axis P2 of rotation of the rotary rotor 31 of the separator 30 coincide with each other in the axial direction. The rotary rotor 31 of the separator 30 in the vertical mill of the comparative example is assumed to rotate clockwise as described above, but the same effect is obtained even if it rotates counterclockwise.

Here, the theoretical classification point of the separator 30 is the equation of motion of the particles of the granular material, and the velocity (central direction velocity) vg toward the central direction between the rotary blades of the rotary rotor 31 and the rotational direction of the rotary rotor 31 By arranging with the velocity (rotational direction velocity) vθ, it can be expressed as the following equation 1.
d∝vg ^0.5 / vθ (Equation 1)
d: Theoretical classification point (μm)
vθ: Speed in turning direction (m / s)
vg: velocity in the center direction (m / s)

The central velocity vg is due to the amount of air flow passing through the rotating blades of the rotary rotor 31, and the turning directional velocity vθ is due to the rotational velocity of the rotary rotor 31. For this reason, it is possible to easily manipulate the theoretical classification point d (that is, the product particle size) by controlling the number of revolutions of the rotary rotor 31 under the condition that the passing air flow rate is constant.

When the theoretical classification point d is uniform in the height direction and the circumferential direction of the separator 30, it is an ideal classification. However, while a substantially uniform turning velocity field (vθ = constant) is formed by the rotation of the rotary rotor 31, as described above, since the central velocity vg is not uniform in the circumferential direction, it is actually In particular, in the circumferential direction, bias (central flow) of the central velocity vg occurs.

Such a partial flow is mainly caused by the relationship between the arrangement of the duct portion 21b up to the product outlet 29 in the upper case 21 and the rotational direction of the rotary rotor 31 of the separator 30. Therefore, in both the vertical crusher of the comparative example and the vertical crusher 1 of the embodiment, the horizontal cross section at a predetermined location is an average value of theoretical classification points d in the circumferential direction when viewed from above from above. With respect to the ideal classification that can be shown, in fact, the distribution of each theoretical classification point d is biased.

For example, like the vertical crusher of the comparative example, the duct portion 21b up to the product outlet 29 has the upper case 21 having a general shape and arrangement, and the center P1 of the lower and

upper cases

22 and 21 and the separator When the rotation center axis P2 of the 30 rotation rotors 31 coincides with each other, and the opening 46 above the rotation rotor 31 is concentric with these, as shown by arrows F1 and F2 in FIG. 6, respectively Airflow entrainment and short path flow occur. The air flow entrainment and the short pass flow are suppressed so as not to substantially occur, for example, in the vertical mill 1 of the embodiment.

Due to the influence of air flow, in the horizontal cross section near the lower end of the separator 30 of the comparative example, the theoretical classification point d tends to be large on the left side of the upper casing 20 when the product outlet 29 is viewed from the front. That is, the theoretical classification point d of the comparative example becomes very large in the region where the influence of the air flow wrap is remarkable. This is because the air flow wraps around with the rotation of the rotating rotor 31 rotating clockwise, and the central velocity vg increases in the left area when the product outlet 29 is viewed from the front.

On the other hand, due to the influence of the short path flow, in the horizontal section near the upper end of the separator 30 of the comparative example, when the product outlet 29 is viewed from the front, the theoretical classification point d is on the product outlet 29 side of the upper casing 20 It tends to grow. That is, the theoretical classification point d of the comparative example becomes very large in the region where the influence of the short path flow is remarkable. This is because the short path flow occurs in the region immediately below the duct portion 21b reaching the product outlet 29, as indicated by the arrow F2 in FIG.

As in this comparative example, the deviation of the theoretical classification point d in the circumferential direction increases the particle size width of the particle size distribution of the product. As a result, the particle size distribution of the product has a wider particle size configuration than what is originally desired to be obtained, and thus there is concern that the quality is adversely affected. In addition, as the theoretical classification point d is biased, the crusher performance is reduced. That is, the fine powder that should normally be taken out as a product is returned to the inside as coarse powder in the region where the theoretical classification point d in the upper casing 20 is large.

Since this brings about unnecessary energy consumption concerning operation of a crusher, it causes not only reduction of the amount of crushing but also increase of power consumption. In addition, when the amount of returned powder and particulate matter increases, the material layer on the rotary table 5 increases and vibration is induced. In order to converge this vibration, the operation can not be stopped from the viewpoint of equipment protection, and the operation will be seriously damaged.

On the other hand, as in the vertical crusher 1 of the embodiment, the center point P3 of the eccentric opening 47 is with respect to the center P1 of the lower and

upper cases

22 and 21 and the rotation center axis P2 of the rotary rotor 31 of the separator 30. In the configuration in which the eccentric arrangement is performed, the theoretical classification point d is extremely small compared to the comparative example even in the region where the influence of the air flow wrap is remarkable and the region where the influence of the short path flow is remarkable. In addition, the overall distribution of theoretical classification points d in the circumferential direction is also less concentrated than in the comparative example.

As described above, in the vertical crusher 1 of the embodiment, it is possible to reduce the deviation of the theoretical classification point d of the separator 30 as much as possible, and as in the air flow F3 shown in FIG. 2, FIG. 3 and FIG. The air flow can be reduced. That is, in the vicinity of the lower end of the separator 30, the influence of the air flow accompanying the rotation of the rotary rotor 31 can be alleviated as much as possible, and in the vicinity of the upper end, the influence of the short path flow can be alleviated as much. The distribution can be made closer to a more ideal circular distribution.

Thereby, the particle size width of the particle size distribution of the product can be reduced, and the quality of the product can be improved. In addition, since it is possible to reduce the amount of particles returned to the inside of the grinder, the power consumption can be improved while increasing the amount of grinding, and the occurrence of vibration can be reduced.

Specifically, in the vertical crusher 1 in the experimental equipment in which the present invention is implemented, the above-mentioned size is SX = SY = 0 as compared with the comparative example having the upper casing 20 of the same shape except for the eccentric plate 49. As a result of conducting an experiment (operation) under the condition of 032D, it was confirmed that the number of revolutions of the rotary rotor 31 for obtaining the same product particle size can be reduced by about 10%. Further, for example, it was confirmed that the pulverizing ability can be increased by about 10% by reducing the circulating material returned to the chute 6, and the power consumption can be further reduced by about 5%, and at the same time the generation of vibration can be reduced.

As described above, according to the vertical crusher 1, the uniformity of the theoretical classification point d of the separator 30 in the crusher can be made uniform, so that the quality of the product can be improved. In addition, since various efficiency designs adapted to various operating conditions and crushing conditions can be appropriately realized even in a general vertical crusher simply by changing the shape and arrangement of the eccentric plate 49, a simple configuration Cost benefits can be enhanced. Although such a simple configuration is particularly effective for retrofitting of an existing vertical crusher, it is very advantageous not only for existing facilities but also for providing new facilities.

The embodiment of the present invention has been described above, but this embodiment is presented as an example, and is not intended to limit the scope of the invention. This novel embodiment can be implemented in other various forms, and various omissions, replacements and changes can be made without departing from the scope of the invention. The embodiment and the modification thereof are included in the scope and the gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Reference Signs List 1 vertical crusher 2 table motor 3 rotor motor 4 reduction gear 5 rotary table 6 chute 7 cone 8 grinding roller 10 casing 12 dam ring 18 control device 19 lower casing 20 upper casing 21 upper case 21 b duct portion 22 lower case 29 Product outlet 30 Separator 31 Rotor 32 Fixed blade 40 Short

path prevention plate

40a,

49a End face

46, 48 Opening 47 Eccentric opening 49 Eccentric plate

Claims

With a rotating table,
A grinding roller that rotates on the rotary table and grinds the raw material supplied onto the rotary table with the rotary table;
A gas inlet for introducing a gas that blows up the granular material made of the crushed raw material;
A separator provided above the rotary table and having a rotating portion for classifying powder particles blown up by the gas introduced from the gas inlet;
An upper casing having a product outlet for storing the separator and taking out the classified powder particles to the outside;
The upper casing is
An eccentric plate is provided above the separator and below the product outlet, the eccentric plate forming an eccentric opening eccentric to the central axis of rotation of the separator.
The separator has a circular opening at the top,
The said eccentric plate consists of a crescent-shaped plate-like member arrange | positioned in the inner area | region of this opening part along the said opening part in planar view from upper direction. Machine.
The eccentric plate is
The rotating portion of the separator rotates clockwise in an orthogonal coordinate system in which the upper casing is viewed from above from above with the product casing located on the left side with the central axis of rotation of the rotating portion of the separator as the origin. When rotating, the center point of the eccentric opening is positioned in the fourth quadrant, and when the rotating portion of the separator rotates counterclockwise, the center point of the eccentric opening is positioned in the first quadrant. The crusher according to claim 1 or 2, wherein the crusher is provided.
The eccentric plate is
The rotating portion of the separator is cylindrical, and the outer diameter is D, and the distance in the X direction from the origin of the central point of the eccentric opening in the orthogonal coordinate system is SX and the distance in the Y direction is SY , The distance of said SX and SY,
(A) 0.015 × D ≦ SX ≦ 0.080 × D [mm],
(B) 0.015 × D ≦ SY ≦ 0.080 × D [mm]
The vertical crusher according to claim 3, wherein the vertical crusher is provided to satisfy the following condition.
In the upper casing, a short path preventing plate is provided above the separator and below the product outlet along the outer periphery of the separator to prevent a short pass from the separator of the gas to the product outlet. Provided
5. The crusher according to any one of claims 1 to 4, wherein the eccentric plate is integrally provided on the short path prevention plate.