JP6549062B2 - Vertical mill - Google Patents

Description

  The present invention relates to a vertical mill particularly suitable for use in pulverizing biomass feedstocks and the like.

  Since the bioenergy obtained from biomass feedstock, which is an organic resource derived from organisms, is carbon dioxide released by combustion absorbed from the atmosphere during the growth process of organisms, fossil fuel derived from fossil resources is used. Can be used to reduce the increase in total carbon dioxide emissions.

Therefore, various techniques have been developed for producing biomass fuels such as solidified fuel and alcohol from biomass raw materials such as thinnings, construction wastes and rice husks.
By the way, in order to manufacture the above-mentioned biomass fuel, it is necessary to grind the above-mentioned biomass materials of about several millimeters to several tens of millimeters to about 500 micrometers according to a use.

On the other hand, the inventors of the present invention have previously proposed a pulverizer capable of pulverizing such solid matter into a fine powder by means of a pulverizing plate which is swirled at a high speed in Patent Document 1 below.
The pulverizer includes a stator housing having a cylindrical barrel, a cylindrical liner fitted on the inner surface of the barrel of the stator housing, and a coaxial liner disposed inside the liner. The rotor, and a plurality of the rotors are provided on the outer peripheral portion of the rotor at intervals in the axial direction and circumferential direction of the rotor, and the plate surfaces are directed in the direction of rotation by the rotor And a grinding plate having a tip close to the inner circumferential surface of the liner.

  According to the pulverizer having the above-described structure, the object to be pulverized passing between the pulverizing plate and the liner is subjected to more disturbed vortices, air vibrations and the like, so that the impact force, shear force and compression greater than those of the conventional pulverizer. Force or the like can be exerted, so that the object to be crushed can be easily crushed to a predetermined particle size.

  On the other hand, in recent years, there has been a demand for a pulverizer with a simpler apparatus and enhanced in the quality and production efficiency of the fine powder, and its improvement has been desired.

JP 2005-324126 A

  The present invention has been made in view of the above circumstances, and it is possible to obtain a pulverized material with uniform particle size without requiring a complicated mechanism, and thus to improve the quality of the pulverized product as a product. It is an object of the present invention to provide a vertical mill.

  In order to solve the above-mentioned subject, invention of Claim 1 makes a cylindrical container which has a cylindrical trunk which a lower end part was closed by a bottom plate, and makes the above-mentioned drum and axis line in this cylindrical container correspond. A plurality of rotation shafts rotatably disposed, a rotor provided below the rotation shafts, and a plurality of circumferentially spaced intervals on an outer peripheral portion of the rotor, and between the inner peripheral surface of the body portion And a feed port formed at a position facing the pulverizing plate of the body portion to feed the mixture of the raw material and air into the cylindrical container, and the inside of the cylindrical container. A vertical mill having a discharge port for discharging a mixture of ground material and air from the upper space of the rotor, wherein an opening is formed in the upper portion of the rotor, and the ground plate of the rotor Inward, the plate surface is directed from the axial side to the outer peripheral side The following the direction of rotation of the vane is inclined to the rear side is characterized in that a plurality spaced above the circumferential direction.

  The invention according to claim 2 is the invention according to claim 1, wherein a classification chamber is provided in the upper part of the cylindrical container, and the partition plate between the classification chamber and the inside of the cylindrical container is centered on the axis. An opening is formed, and a plurality of fingers radially extending in the horizontal direction from the axis side are provided on the outer periphery of the rotation shaft located in the opening.

  Furthermore, in the invention according to claim 3, in the invention according to claim 1 or 2, an air chamber is provided around the outer periphery of the body in an airtight manner and the air inlet pipe is connected. The air chamber is in communication with the supply port.

  In the invention according to any one of claims 1 to 3, the raw material supplied into the cylindrical container together with the air from the supply port is crushed with the air while being crushed between the inner peripheral surface of the barrel and the rotating grinding plate. It is sent out to the space above the rotor. And since the speed of updraft in this upper space falls, comparatively coarse ground material falls without being able to rise.

  Then, while forming an opening in the upper part of the above-mentioned rotor, the above-mentioned circle which made the board face incline towards the back side of the direction of rotation gradually from the upper line side to the outer peripheral part side inside the crushing plate of the above-mentioned rotor Since a plurality of pieces are disposed circumferentially at intervals, the crushed material dropped into the rotor from the opening is sent to the outer peripheral side by the rotation of the blades, and the inner peripheral surface of the crushing plate and the barrel again. It is crushed between.

  In this manner, by circulating and grinding relatively coarse ground products in a cylindrical container, ground products with uniform particle sizes can be obtained without requiring a complicated mechanism, and thus ground products to be products. Can improve the quality of

  In addition, according to the second aspect of the present invention, the opening is formed in the partition plate between the classification chamber provided in the upper part of the cylindrical container, and the axis side is formed on the outer periphery of the rotating shaft located in the opening. As a result of providing the plurality of fingers radially extending in the horizontal direction, when passing between the rotating fingers, the crushed material with a larger particle diameter collides with the fingers and the rising speed decreases. As a result, the ground material having a certain particle size or more can be dropped downward and reground similarly.

  Therefore, by appropriately selecting the number of fingers, it is possible to obtain a predetermined classification effect inside the vertical mill.

  By the way, when using, for example, the vertical mill according to the present invention for pulverizing biomass material, the biomass material is generally moist, and in particular, thinning material contains several tens of water. On the other hand, in order to use the above-mentioned biomass raw material for biomass fuel, it is required to make the moisture of the crushed product about 10% or less.

  On the other hand, in this vertical mill, when the raw material is crushed, heat is generated in the cylindrical container due to the collision and friction between the raw material and the crushed plate or between the raw materials. Therefore, in the invention according to the third aspect, an air chamber is provided on the outer periphery of the barrel of the cylindrical container, and a part of the heat generation is absorbed by the air in the air chamber to raise the temperature. The raw material can be dried by the above-mentioned air to be mixed prior to the feeding into the container.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the grinding system of the raw material in which one Embodiment of this invention is used. It is a longitudinal section showing one embodiment of the present invention. It is a disassembled perspective view which shows the rotor of FIG. It is a bottom view which shows the finger of FIG.

  Fig. 1 is a source of biomass fuel such as solidified fuel and alcohol by crushing and classifying biomass raw materials such as thinning materials, construction waste materials or rice husks according to one embodiment of the vertical mill according to the present invention Fig. 1 shows a grinding system for producing a product.

  This grinding system comprises a vertical mill 1 according to an embodiment of the present invention to which the biomass raw material and air are supplied, and a cyclone for classifying the ground material milled and discharged in the vertical mill 1 to take out the product. (Classifying device) 2, Bag filter (classifying device) 3 for collecting finely pulverized material from air discharged from the cyclone 2, and suction of the air from the vertical mill 1 side, the vertical mill 1 side And an air supply device 4 for forming an air flow directed to the bag filter 3 side.

FIGS. 2 to 4 show the vertical mill 1 and reference numeral 10 in the drawings is a cylindrical container.
The lower end portion of the cylindrical body portion 11 is closed by the bottom plate 12 and the classification chamber 13 is formed in the upper portion of the cylindrical container 10, and the motor 14 (see FIG. The rotary shaft 15 driven by 1) is rotatably supported.

  The lower rotor 17 is fixed by bolting the upper rotor 16 and the lower rotor 17 to each other. Here, in the upper rotor 16, the upper disc 18 and a plurality (eight in the drawing) of the support portions 19 a are radially spaced at equal intervals in the circumferential direction, and are axially spaced from each other. The shredder plates 20 are integrated by a plurality of (eight in the drawing) band-like crush plates 20 disposed between the outer peripheries of the respective members. It is disposed at equal intervals in the circumferential direction so as to face the inner circumferential surface of the.

  On the other hand, in the lower rotor 17, a support plate 19 having the same shape as the upper rotor 16 and a lower disc 21 having the same diameter as the upper disc 18 are arranged at intervals in the axial direction, In the same manner, the crush plate 20 is formed so that each plate surface faces the inner peripheral surface of the body portion 11 and is circumferentially integrated. It is arranged at equal intervals in the direction.

  A plurality (16 in the figure) of circular openings 22 are bored in the upper disc 18 so as to be located between the support portions 19a of the support plate 19 in a plan view. Further, the lower disc 21 is formed with an opening 23 in which a portion located between the support portions 19a of the support plate 19 in a plan view is cut like a fan.

  Further, on the central portion side of the upper and lower rotors 16 and 17, an inner circumferential plate 24 which is connected to the upper and lower disks 18 and 21 and the support plate 19 and surrounds the rotary shaft 15 is provided. And between the support part 19a located between the inner peripheral plate 24 and the crushing plate 20 and the upper and lower disks 18 and 21, the vanes 25 are provided at equal intervals in the circumferential direction. .

  The blades 25 provided in the upper and lower rotors 16 and 17 incline the plate surface toward the outer peripheral side gradually from the axis side toward the outer peripheral side, so that the internal air is rotated to the outer peripheral side during rotation. It is arranged to send it out. The same blade 25 is also provided on the lower surface of the lower disc 21 in the lower rotor 17.

  The upper and lower rotors 16 and 17 are disposed such that the crushing plates 20 are continuous with each other in the axial direction, and the support plates 19 are connected by bolts (not shown) to form a rotor. There is. The rotor having the above configuration is rotatably provided on the bottom plate 12 of the cylindrical container 10 by the rotation shaft 15. Here, an annular recess is formed in the outer peripheral portion of the bottom plate 12, and blades 25 fixed to the lower surface of the lower disc 21 are disposed in the recess with a predetermined gap therebetween.

  Further, the outer diameter of the rotor, that is, the outer diameter of the upper disc 18, the support plate 19 and the lower disc 21 is a gap between the crushing plate 20 and the inner peripheral surface of the body 11 where the raw material can be crushed. Are set to the dimensions to be formed. Further, the height dimension of the rotor (the length dimension in the axial direction) is set to 1/2 or less of the length dimension in the axial direction of the body portion 11. Space S is formed.

  Then, at a position facing the side plate 20 of the upper rotor 16 on the side surface of the barrel 11 of the cylindrical container 10, a supply port 30 for introducing a mixture of biomass raw material such as thinning material and air into the cylindrical container 10 is It is arranged.

  Further, an air chamber 31 airtightly enclosed by a cylindrical side plate 31a, a top plate 31b and a bottom plate 31c having a diameter larger than that of the trunk portion 11 is provided on the outer periphery of the trunk portion 11 located above the supply port 30. It is done. The air introduction pipe 32 is connected to the top plate 31b, and the communication pipe 33 to the supply port 30 is connected to the bottom plate 31c.

  On the other hand, a circular opening 35 coaxial with the axis of the rotary shaft 15 is formed in the partition plate 34 between the classification chamber 13 provided in the upper part of the cylindrical container 10 and the cylindrical container 10. The upper end portion is rotatably supported by the top plate 11 a of the trunk portion 11 by being inserted into the opening portion 35.

  In addition, a disc 36 having a diameter smaller than the inner diameter of the opening 35 is horizontally fixed at a position facing the opening 35 of the rotating shaft 15, and a plurality of In the drawing, 24 strip-shaped fingers 37 are arranged at equal intervals in the circumferential direction, and fixed so as to radially extend from the disc 36. Here, the disc 36 is disposed at substantially the same level as the opening 35 of the partition plate 34, and the tip of the finger 37 is disposed so as to cover the edge of the opening 35 from below.

  The cyclone shown in FIG. 1 is a mixture of the pulverized material of the raw material and air which has flowed into the classification chamber 13 from the upper space S of the rotor in the cylindrical container 10 through the opening 35 on the outer periphery of the classification chamber 13. An outlet 38 is formed for feeding to 2.

  In the vertical mill having the above configuration, the biomass raw material and the air are introduced into the cylindrical container 10 from the supply port 30 by suction by the air supply device 4, and the crushed plate 20 rotates with the inner peripheral surface of the barrel 11. While the raw material is crushed and sent out to the upper space S of the rotor together with the air. And since the speed of updraft in this upper space S falls, comparatively coarse ground material falls without being able to rise.

  Then, the crushed material which has fallen falls into the inside of the rotor from the opening 22 formed in the upper disk 18 of the upper rotor 16 of the rotor, and is then sent to the outer peripheral side by the rotation of the blades 25 and again the crushing plate It is crushed in the process of rising between 20 and the inner circumferential surface of the body 11.

  In addition, the coarse crushed material which is not sent to the outer peripheral side by the air blowing by the blades 25 falls from the opening 23 formed in the lower disc 21 of the lower rotor 17 to the bottom plate 12 side. It is crushed between the blades 25 provided on the lower surface of the disc 21 and sent to the outer peripheral side, and further crushed in the process of rising between the crushing plate 20 and the inner peripheral surface of the body portion 11.

  In this way, even if crushed between the inner peripheral surface of the cylindrical container 10 and the crush plate 20 of the rotor, the crushed material still having a large particle diameter drops from the space S to the rotor side, so that the cylindrical container is 10 are circulated and further crushed, and are sent to the classification chamber 13 as a pulverized material having a small particle size.

  Then, a relatively small particle size of the crushed material that did not fall in the space S, and a pulverized material whose particle size is reduced by being circulated and crushed in the cylindrical container 10 are carried along with the rising air flow to be the cylindrical container. The inside 10 is raised and flows into the classification chamber 13 from between the rotating fingers 37. At this time, the crushed material having a larger particle diameter collides with the finger 37 and decreases the rising speed between the rotating fingers 37, and the particles fall downward and are crushed again by the grinding plate 20.

  As a result, only the pulverized material having a predetermined particle size or less is sent from the classification chamber 13 to the above-described cyclone 2 through the discharge port 38. Then, in the cyclone 2, a pulverized material having an average particle diameter of about 500 μm is recovered as a product, and in the bag filter 3, a finely pulverized product of several tens of μm is recovered as a product.

  In the vertical mill, when the raw material is crushed between the cylindrical container 10 and the grinding plate 20, heat is generated in the cylindrical container 10 due to the collision and friction between the raw material and the grinding plate 20 or between the raw materials. Then, the air in the air chamber 31 provided on the outer periphery of the body portion 11 of the cylindrical container 10 is heated by the heat, and the raw material is dried by the heated air and supplied from the supply port 30 into the cylindrical container 10 .

  As described above, according to the vertical mill 1, a wide space S is formed above the rotor in the cylindrical container 10, and the opening 22 is formed in the upper disc 18 of the rotor, and Since the blades 25 for sending the internal air to the outer peripheral side are provided inside the crushing plate 20, the speed of the rising air flow is reduced in the space S, so that relatively coarse crushed material which can not rise and falls. Can be fed from the inside to the outside of the rotor and crushed again between the cylindrical container 10 and the grinding plate 20.

  As a result, it is possible to obtain a ground product with uniform particle size without requiring a complicated mechanism by circulating and grinding a relatively large ground product in the cylindrical container 10, and thus the product ground. Can improve the quality of

  In addition, an opening 35 is formed in the partition plate 34 between the classification chamber 13 provided in the upper part of the cylindrical container 10 and radially extending in the horizontal direction on the outer periphery of the rotating shaft 15 located in the opening 35 Because of the provision of the plurality of fingers 37, when passing between the rotating fingers 37, the crushed material having a relatively large particle diameter collides with the fingers 37 to reduce the rising speed, Can be dropped.

  Therefore, by appropriately selecting the number of the fingers 37, a predetermined classification effect can be obtained inside the vertical mill.

  In addition, the biomass material supplied to the supply port 30 contains, for example, about 40% of water for thinning, about 20% for construction waste, and about 14% for rice husk. An air chamber 31 is provided on the outer periphery of the body portion 11 of the cylindrical container 10, and a part of the heat generated at the time of crushing of the raw material in the cylindrical container is absorbed by the air in the air chamber 31 to raise the temperature. The biomass raw material can be dried in a stage prior to being fed into the cylindrical container 10 from 30. Therefore, the moisture of the product recovered from the cyclone 2 and the bag filter 3 can be easily required at about 10%. It can be

  In addition, although the said embodiment demonstrated only the case where biomass raw materials, such as thinning material, were crushed with the vertical mill of one embodiment of this invention, this invention is not limited to this, The other It is possible to use for grinding of various grinding objects.

Reference Signs List 1 vertical mill 10 cylindrical container 11 barrel 12 bottom plate 13 classification chamber 14 motor 15 rotary shaft 16 upper rotor 17 lower rotor 18 upper disk 19 support plate 20 crushed plate 21 lower disk 22, 23 opening 24 inner circumferential plate 25 Vane 26 Disc 30 Supply port 31 Air chamber 32 Air introduction pipe 33 Connecting pipe 34 Partition plate 35 Opening 37 Finger 38 Exhaust port S Space

Claims (3)

A cylindrical container having a cylindrical body portion whose lower end is closed by a bottom plate, a rotary shaft rotatably arranged with the body portion and the axis line in the cylindrical container, and a lower portion of the rotary shaft A rotor provided, a plurality of circumferentially spaced intervals on the outer peripheral portion of the rotor, and a crushing plate provided so as to be able to crush the material between the inner peripheral surface of the body and the body A supply port for supplying a mixture of the raw material and air into the cylindrical container at a position facing the grinding plate, and a crushed material of the raw material and air from the space above the rotor in the cylindrical container In a vertical mill equipped with an outlet for discharging the mixture,
Forming an opening at the top of the rotor;
A plurality of blades are disposed at an interval in the circumferential direction, inward of the crushing plate of the rotor, and in which the plate surface is gradually inclined rearward in the rotational direction from the axial side toward the outer peripheral side. Vertical mill characterized by A classification chamber is provided in the upper portion of the cylindrical container, and an opening centering on the axis is formed in a partition plate between the classification chamber and the inside of the cylindrical container,
The vertical mill according to claim 1, wherein a plurality of fingers radially extending in the horizontal direction from the axis side are provided on an outer periphery of the rotation shaft located in the opening.   The air chamber is provided on the outer periphery of the body in an airtight manner and the air introduction pipe is connected to the air chamber, and the air chamber is communicated with the supply port. Vertical mill as described in.

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