JPH09192523A - Crushing method for plastic waste and crushing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the productivity of crushed pieces without deteriorating the life of a blade by providing a rough crushing step for crushing a supplied plastic waste in a slender form and a fine crushing step for crushing the waste in a fine flake form. SOLUTION: A PET bottle changed as a plate shape is supplied to a rough crushing device 25 by a transport conveyor 3c, then pulled inward by the pawls 31 of mutually counter-rotating blades 29 and is crushed by a continuously acting shearing force thereon. The slender band-like flake 1a obtained by crushing is supplied to a metal removing device 35 by transport conveyors 3d, 3e. If no metal is contained, the flake 1a is supplied to a fine crushing device 47 by transport conveyors 3f, 3g and is crushed between a rotary blade 7 and a fixed blade 9. If the size of the flake 1c obtained by this crushing is larger than a specified size, it is again returned to the upper part to receive the crushing process repeatedly. If the size of the flake 1c is smaller than the specified size, it is allowed to pass through the mesh 12 of a screen 13 and is transported to another step by a fan 23.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for crushing large plastic waste into small plastic waste.

[0002]

2. Description of the Related Art In recent years, with the exhaustion of resources, the reuse of resources has been actively carried out in various industries. A plastic material is one of them, and used plastic products are collected, crushed into fine flakes, re-dissolved and reused. At the time of reuse, it is necessary to separate each plastic material.

However, few plastic products in the market are made of a single material,
Most of them are composed of multiple different materials. For example, the container body is polyethylene terephthalate (hereinafter, P
In so-called PET bottles made by ET), even if the container body is made of PET, the lower hakama part (leg part)
Is made of polyethylene (hereinafter, PE), the handle is made of polypropylene (hereinafter, PP), the cap is made of metal, and the label attached to the outer surface of the container body is made of paper. Or Here, the cap can be removed, but in some cases, the cap may be recovered while being attached. In addition, the hakama portion is generally joined to the container body and cannot be separated, and the handle portion is often unseparable or difficult to separate from the container body.

Therefore, when the PET material in the waste PET bottle is reused, the metal is removed from the metal after crushing the waste PET bottle including the hakama portion, the handle portion, the label and the cap not removed into fine flakes. Must be removed by equipment.

Here, a conventional crushing apparatus and method for crushing plastic products such as PET bottles will be described.
The collected PET bottle 1 was compressed into a plate and reduced in volume to approximately 1
It is bundled in a bale of m ³ (1m x 1m x 1m) and transported to the factory. The bale carried in is unraveled into a plate-shaped single bottle, the outer surface of which is washed in the previous step, and the selected PET bottle 1 such as a PVC bottle or a PET bottle is transferred by the bottle conveyor 3 as shown in FIG. It is conveyed in the direction of the arrow and supplied to the wet crusher 5.

The wet crusher 5 has a rotary blade 7 and a fixed blade 9 for crushing the PET bottle 1 into fine flakes inside the accommodating portion 10, and the blade width direction of the fixed blade 9 is the rotation axis. A large number of fixed blades 9 are provided in parallel in a posture that substantially coincides with the axial direction of the.

On top of the wet crusher 5, a PET bottle 1
A discharge hole 11 for discharging water is provided for the purpose of cleaning. A screen 13 having a large number of transmission holes 12 is provided below the rotary blade 7.

Below the screen 13, crushed P
ET bottle 1 and screw feeder 1 to convey water
5 are provided. The PET bottle 1 and water conveyed by the screw feeder 15 are sent to the centrifugal dehydrator 17.

Inside the centrifugal dehydrator 17, an ascending air current is generated by the propeller 19, and the crushed pieces ascend in the centrifugal dehydrator 17 due to this ascending air current. The water adhering to the crushed pieces is blown off and separated from the crushed pieces. The crushed pieces are discharged from the upper part of the centrifugal dehydrator 17 together with air and sent to the air cyclone 21. The air cyclone 21 uses an air flow. The air cyclone 21 discharges air from the upper part and discharges crushed pieces from the lower part. The discharged crushed pieces are transferred to the next step by the fan 23.

The wet crusher 5 having the above-mentioned structure is used for the PET bottle 1
In order to crush, water is discharged from the upper part of the wet crusher 5,
The rotary blade 7 is rotated, and the PET bottle 1 is crushed by the cooperation of the rotary blade 7 and the fixed blade 9. However, one rotation of the rotary blade 7 does not cause the PET bottle 1 to form flakes of a certain size or less, and many times of rotation produces flakes of a certain size or less. The flake-shaped PET bottle 1 having a certain size or less is sent to the screw feeder 15 through a large number of permeation holes 12 provided in the screen 13.

[0011]

However, in order to crush the PET bottle, it is necessary to supply the PET bottle between the rotary blade and the fixed blade. However, when the PET bottle is large, the PET bottle is large. Since the bottle is not easily caught by the rotary blade, the crushing amount of the PET bottle is reduced. Also,
Since a step of removing water adhering to the crushed pieces of the PET bottle after crushing is provided, it took time to obtain fine crushed pieces of the PET bottle. For this reason, the productivity of the crushed pieces of the PET bottle decreased. Further, unless the number of times of crushing by the rotary blade and the fixed blade is increased, it is not possible to make crushed pieces of a certain size or smaller, so the load on the blade is increased and the life is reduced. Further, there is a problem that the cost of water treatment increases because the water is supplied.

The present invention has been made in view of the above problems of the prior art, and a crushing method and a crushing method for a plastic waste material capable of improving the productivity of crushed pieces without shortening the life of the blade. The purpose is to provide a device.

[0013]

The present invention adopts the following means in order to solve the above problems. The points of the present invention will be briefly described below.

The present invention relates to a method for crushing plastic waste material into fine flakes, such as a coarse crushing step of crushing the supplied plastic waste material into an elongated shape, and the plastic waste material crushed into the elongated shape into finer flakes. A method of crushing plastic waste material, comprising: a fine crushing step of crushing.
Corresponding to). By providing the coarse crushing step before the fine crushing step, it is possible to prevent the life of the crushing blade from being shortened.Also, by eliminating the washing treatment with water, it is possible to improve the flake productivity and running. This is because it is possible to prevent an increase in cost.

The plastic waste material supplied to the coarse crushing step is preferably substantially plate-shaped (corresponding to claim 2). This is because the scrap of the plastic waste material on the rotary blade can be improved and the flake productivity can be improved.

Further, a metal removing step for removing a metal substance may be provided between the coarse crushing step and the fine crushing step (corresponding to claim 3). This is because the quality of the flakes can be improved and the life of the blade in the fine crushing step can be extended by eliminating the metallic foreign matter.

Further, according to the present invention, in a device for crushing plastic waste material into fine flakes, rotary blades facing each other and rotating in opposite directions are provided, and the plastic waste material is constantly meshed with both rotary blades for continuous shearing. Then, a coarse crushing means for crushing into an elongated shape, a housing portion for housing plastic waste material on a screen having a large number of permeation holes in the lower portion, a rotary blade rotatably installed inside the housing portion,
With a fixed blade fixed to the outside of the rotary blade in the accommodating part, the plastic waste material in the accommodating part is further finely sheared by the rotary blade and the fixed blade, and flaky crushed pieces of a predetermined size or less penetrate the screen. And a fine crushing means that passes through the holes (corresponding to claim 4).

Since the coarse crushing means is provided in the preceding step of the fine crushing means, the elongated crushed pieces supplied to the fine crushing means are small. Therefore, it is possible to prevent a decrease in the supply amount of the plastic waste material between the rotary blade and the fixed blade, and it is possible to improve the productivity.

Further, the shear width for the plastic waste material by the rotary blade of the coarse crushing means may be set to 20 mm to 40 mm (corresponding to claim 5). This is because the metal contained in the waste plastic material can be easily removed.

Further, a metal removing means for removing a metal material may be provided between the coarse crushing means and the fine crushing means (corresponding to claim 6). The plastic waste material is not limited to materials such as PET, PE and PP.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. First, a device for crushing plastic waste material according to the present invention will be described. The same parts as those of the conventional example will be described with the same reference numerals.

The collected PET bottles are compressed and reduced in a plate shape, bound into a bale of about 1 m ³ (1 m × 1 m × 1 m), and transported to the factory. The bale carried in is unleashed into a plate-shaped single bottle, the outer surface of which is washed in the previous process,
Selected PET bottles such as C bottle and PET bottle 1
As shown in FIG. 3, is transported in the direction of the arrow by the bottle transport conveyor 3 and supplied to the coarse crushing device 25.

The coarse crushing device 25 has a first opening 27 at the top.
At the lower part of the first opening 27, there are provided rotary blades 29 facing each other and rotating in opposite directions. The rotary blade 29 is a plate-shaped PET, as shown in FIG.
It has a claw blade 31 for pulling in the bottle 1. In the rotary blade 29, a large number of rotary blades 29 are provided on a single rotary shaft 32 at regular intervals and perpendicular to the axis. The claw blade 31
Is provided on one rotary blade 29, and each claw blade 31 is
It is provided at intervals of 120 degrees. Claw blade 3 of each rotary blade 29
The positional relationship of No. 1 is spirally arranged around the axis at regular intervals in a stepwise manner.

A second opening 33 is provided at the bottom of the rotary blade 29. A bottle transport conveyor 3d is provided below the second opening 33. Bottle conveyor 3d, e
The elongated strip-shaped flakes 1 a conveyed by are supplied to the metal removing device 35. A first opening 37 is provided on the upper portion of the metal removing device 35, and a sensor 39 for detecting a change in magnetic field is provided on the lower portion of the first opening 37. Below the sensor 39, an air jetting means 41 for removing metallic substances is provided. The lower portion of the air ejection means 41 has a second opening 43 for ejecting the flakes 1a from which the metal material has been removed.
A third opening 45 for discharging the metal object is provided in a direction away from the metal.

Below the second opening 43, a bottle carrying conveyor 3f is provided. Bottle conveyor 3f, g
The flakes 1b conveyed by are supplied to the fine crushing device 47. The fine crushing device 47 has a first opening 49 at the top.
And has flakes 1 at the bottom of the first opening 49.
A rotary blade 7 and a fixed blade 9 for crushing b into smaller pieces are provided in the accommodating portion 10, and a large number of rotary blades 7 are provided with the blade width direction of the rotary blade 7 substantially aligned with the axial direction of the rotary shaft 32.
Are provided in parallel.

Below the rotary blade 7, a screen 13 having a large number of transmission holes 12 is provided. Screen 1
In the lower part of 3, there is provided a second opening 51 for discharging the flakes 1c. The second opening 51 is connected to a fan 23 for transporting the flakes 1c to another process.

Next, the method for crushing the plastic waste material of the present invention will be described. The plate-shaped PET bottle 1 which is a raw material of the flakes 1c is conveyed by the bottle conveying conveyor 3c in the direction of the arrow and is supplied to the coarse crushing device 25 through the first opening 27. PET bottles supplied 1
Are mounted on the upper part of the rotary blade 29 that rotates in the opposite directions, as shown in FIG. PET bottle 1 has rotary blade 2
It is drawn in between both rotary blades 29 by the claw blade 31 provided in 9. Since many claw blades 31 are provided and arranged in a spiral shape, the supplied PET bottle 1 does not stay on both rotary blades 29. Also, the rotary blade 29
The outer peripheral edges of both ends of the rotary blade 29 in the width direction form a cutting portion, and the PET bottle 1 is crushed by the shearing force continuously acting by the cutting portion. The cutting width is the same as the blade width of the rotary blade 29.

The distance between the rotary blades 29 is 20 mm to 40 mm.
It is a degree. This is because the crushed pieces of the PET bottle 1 to be cut can be prevented from being removed by the air ejection means 41, and the metal contained in the crushed pieces can be easily removed.

The crushed PET bottle 1 becomes an elongated strip-shaped flake 1a, which is placed on the bottle conveying conveyor 3d through the second opening 33. The elongated strip-shaped flakes 1a are transported by the bottle transport conveyors 3d, e and supplied to the metal removing device 35 through the first opening 37. The elongated strip-shaped flakes 1a naturally fall due to gravity and pass over the sensor 39. The sensor 39 generates a constant magnetic field on the surface of the sensor 39 and outputs a change in the magnetic field as a change in voltage. Therefore, when the elongated strip-shaped flakes 1a contain metal, the air jetting means 41 is operated based on the output value of the sensor 39 to blow the metal away. The blown metal is rejected to the outside of the metal removing device 35 through the third opening 45.

On the other hand, the elongated strip-shaped flakes 1a containing no metal are placed on the bottle conveyer 3f through the second opening 43 opening below the air jetting means 41. The elongated strip-shaped flakes 1b are transported by the bottle transport conveyors 3f, g and supplied to the fine crushing device 47 through the first opening 49. The supplied elongated strip-shaped flakes 1b are crushed by the shearing force acting between the rotary blade 7 and the fixed blade 9 in cooperation with the rotary blade 7 and the fixed blade 9.

If the size of the crushed flakes 1c is not less than a predetermined size, the crushed flakes are returned to the upper part by the rotary blade 7 and crushed repeatedly. If the size of the crushed flakes 1c is smaller than a predetermined size, the flakes 1c are sent to the second opening 51 through a large number of transmission holes 12 provided in the screen 13, and are separated by the fan 23 in another step. Be transported to.

The crushing process of the waste plastic material is
It is a continuous flow, not an interruption.

[0033]

As described above, according to the present invention,
By providing coarse crushing means in the previous step of the fine crushing means and eliminating washing with water in the fine crushing means, it is possible to extend the life of the blade for crushing plastic waste materials, and to produce crushed pieces of plastic waste materials. It is possible to improve the property and reduce the running cost.

[Brief description of the drawings]

FIG. 1 is a flow diagram according to an embodiment of the present invention.

FIG. 2 is a perspective view of a rotary blade used in the coarse crushing device according to the embodiment of the present invention.

FIG. 3 is a flow diagram showing a conventional example.

[Explanation of symbols]

 1 PET Bottle (Plastic Waste Material) 1a, 1b, 1c Flakes 7 Rotating Blade 9 Fixed Blade 10 Housing Section 12 Transmission Hole 13 Screen 25 Coarse Crushing Device (Coarse Crushing Process) 29 Rotating Blade 35 Metal Removing Device (Metal Removing Process) 47 Fine Crushing device (fine crushing process)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuaki Takemoto Mitsuishi Chemical Engineering Co., Ltd. 2-6 Nakase 2-chome, Mihama-ku, Chiba-shi, Chiba

Claims (6)

[Claims] 1. A method for crushing plastic waste material into fine flakes, comprising a coarse crushing step of crushing the supplied plastic waste material into an elongated shape, and further crushing the plastic waste material crushed into the elongated shape into flaky shapes. A method for crushing plastic waste material, which comprises a fine crushing step. 2. The method for crushing plastic waste material according to claim 1, wherein the plastic waste material supplied to the rough crushing step is substantially plate-shaped. 3. The method of crushing plastic waste material according to claim 1, further comprising a metal removing step of removing a metal material between the coarse crushing step and the fine crushing step. 4. An apparatus for crushing plastic waste material into fine flakes, comprising rotary blades opposed to each other and rotating in opposite directions, and the plastic waste material is constantly meshed with both rotary blades for continuous shearing to form an elongated shape. Coarse crushing means for crushing into pieces, a storage part for storing plastic waste on a screen having a large number of permeation holes in the lower part, a rotary blade rotatably installed inside the storage part, and a rotary blade in the storage part With a fixed blade fixed to the outside, the plastic waste material in the storage section is further shredded by the rotary blade and the fixed blade, and flake-like crushed pieces of a predetermined size or less pass through the permeation holes of the screen. An apparatus for crushing plastic waste material, characterized by comprising: 5. The crushing apparatus for crushing plastic waste material according to claim 4, wherein a shear width of the rotary crushing means with respect to the plastic waste material is set to 20 mm to 40 mm. 6. The plastic waste material according to claim 4, further comprising a metal removing unit that removes a metal material between the coarse crushing unit and the fine crushing unit. Crushing equipment.