JPH10315235A - Method and apparatus for comminuting waste - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent leakage of a microwave for heat treating by rapidly conducting heat treating (drying and high temperature heating) to continuously conduct the heating and breaking treatment. SOLUTION: The apparatus for comminuting waste comprises a biaxial shearing machine 16 for shearing to comminute plastic waste, a conveyor belt 2 for feeding the waste to the machine 16, and a microwave heat treating unit 18 for emitting a microwave to the waste fed by the belt 2 at an intermediate position of a first feeding passage 13 to heat treat the waste. Thus, the microwave is emitted to the waste to heat treat it, and then the waste is comminuted. And, microwave shielding curtains 11a, 11b are provided in a base end and an end of the passage 13, and a microwave shielding curtain 11c is also provided at a comminuted piece outlet 12 to prevent leakage of the microwave.

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 waste, and more particularly to a method and apparatus useful for crushing and recycling plastic molded materials and plastic waste in the form of parts.

[0002]

2. Description of the Related Art When reusing plastic molded materials such as printed circuit boards or plastic waste in the form of parts as resources such as structural materials, building materials, or fillers for insulating materials, the plastic waste is crushed. The crushed material (finely crushed material or small pieces) thus obtained is used as a resource of the structural material or the like.

One example of such a recycling method is as follows.
There is a “method of recycling printed circuit board waste” previously disclosed in Japanese Patent Application Laid-Open No. 6-296957, which is partially implemented.

In this method, a printed circuit board having glass fiber as a reinforcing material and an epoxy resin as a base material and a printed circuit board on which components are mounted are subjected to a heat treatment in an atmosphere containing oxygen to thereby remove copper contained in the printed circuit board. After oxidizing the metal such as, or finely pulverized and used as a structural material, or the printed board, after finely pulverized, heat-treated in an atmosphere containing oxygen contained in the printed board It is characterized in that metal such as copper is oxidized and used as a structural material or the like. The finely pulverized material thus obtained is added to a matrix such as an epoxy resin to form a structural material, a building material, or an insulating material. Is manufactured, since the metal component is oxidized, the binding to the matrix is increased, and the electrical insulation is increased.
As compared with the case of using a finely pulverized material which is not subjected to the above-described method, the mechanical properties of the structural material and the building material and the electrical properties of the insulating material can be improved.

[0005]

In the crushing of plastic molded materials and plastic waste in the form of parts, the plastic waste is generally crushed at a high temperature without heat treatment. Therefore, a large amount of water is contained in the plastic waste. In the case where it is attached or absorbed, in order to remove these waters, in a batch process, a crushing process is performed after performing a drying process, or a drying process is performed after performing a crushing process. It lacks continuous processing because it is processing.

[0006] Also, a "method of recycling printed circuit board waste" disclosed in the above-mentioned Japanese Patent Application Laid-Open No. 6-296957.
Performs a heat treatment before or after the crushing process. However, in the heater heating method considered as a specific conventional means of the heat treatment, a large installation space is required for the heating device, and the heat treatment takes time. .

Further, when crushing plastic waste that has been wetted with water and to which a large amount of water has adhered as it is, there is a problem that the cutter of the crusher and corrosion of peripheral components are promoted.

Further, plastic waste has a considerably high elastic modulus at around ambient temperature, and therefore,
When shearing and crushing plastic waste in an ambient temperature condition using a twin-shaft shearing machine, a large breaking energy is required, and the driving energy of the driving motor for the twin-shaft shearing machine increases, so a large-capacity driving motor must be provided. Must.

Accordingly, the present invention has been made in view of the above-mentioned prior art to quickly perform a heat treatment (drying treatment and high temperature treatment) so that the heat treatment and the breaking treatment can be performed continuously. This is one issue.

[0010] It is a second object of the present invention to prevent leakage of microwaves for performing heat treatment.

[0011]

The method for crushing plastic waste according to the present invention for solving the first problem is a method for crushing waste which is easily heated by microwaves, and irradiates the waste with microwaves. And then performing a crushing process after performing the microwave heating process.

Further, the plastic waste crushing apparatus of the present invention is a waste crushing apparatus which is easily heated by microwaves, and crushing means for crushing the waste, and transferring the waste to the crushing means. It is characterized by comprising a transfer means and a microwave heat treatment means for irradiating the waste transferred by the transfer means with a microwave to perform a microwave heat treatment.

[0013] In the crushing apparatus, the crushing means is a biaxial shearing machine.

Further, in the crushing apparatus of the present invention for solving the second problem, in any one of the crushing apparatuses, at least a microwave irradiating section of the waste by the microwave heating means is provided with the microwave. A microwave shielding means for surrounding the periphery of the wave irradiation unit and shielding the microwave.

[0015]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of a microwave heating type biaxial shear crusher according to an embodiment of the present invention.
FIG. 2 is a sectional view showing a schematic configuration inside the microwave heating type biaxial shear crusher.

As shown in FIGS. 1 and 2, a hopper 1 is provided on the left side of the figure for charging a plastic molding material and plastic waste in the form of parts. Is connected to the base end of the first transfer path 13. The conveyor belt 2 for transferring plastic waste is provided inside the first transfer path 13 so as to extend over the entire length of the first transfer path 13.

The front end of the first transfer path 13 is connected to a case 15 of a crushing section, in which a biaxial shearing machine hopper 7 and a biaxial shearing machine hopper 7 located below the biaxial shearing machine hopper 7 are provided. A shearing blade 8 is provided. The biaxial shearing blade 8 is provided with a drive motor 9 provided outside the case 15.
The plastic waste is sheared and crushed by being driven by the drive motor 9. That is, the biaxial shearing machine 16 is constituted by the biaxial shearing machine hopper 7, the biaxial shearing blade 8, and the drive motor 9.

The drive motor 9 has its rotating shaft connected to the above-mentioned plastic waste transfer conveyor belt 2 and a plastic waste (crushed piece) transfer conveyor belt 10 described later by connecting means (not shown). ,
The conveyor belts 2 and 10 are also driven to circulate.

A lower part of one side surface 15a of the case 15 is provided with a second transfer path 14 projecting horizontally, and the conveyor belt 10 is provided in the lower part of the second transfer path 14 and the inside of the case 15. 15 is provided from the other side surface 15 b to the crushed piece outlet 12 at the tip of the second transfer path 14.

At the intermediate position of the first transfer path 13, a microwave heating apparatus 18 for heating plastic waste is incorporated. The microwave heating apparatus 18 includes a microwave power source 3, a microwave oscillator 4 electrically connected to the microwave power source 3, and an intermediate position between the microwave oscillator 4 and the first transfer path 13. It comprises a waveguide 5 interposed therebetween, and a fan 6 provided in a connection portion between the waveguide 5 and the first transfer path 13. The fan 6 is also connected to the drive motor 9 by connection means (not shown), and is driven to rotate by the drive motor 9.

Microwave shielding curtains 11a and 11b are provided in the base end and the front end of the first transfer path 13, respectively. Further, a microwave shielding curtain 11c is also provided at the crushed piece outlet 12 at the end of the second transfer path 14.

Therefore, in the microwave heating type biaxial shear crushing apparatus having the above-described structure, plastic waste is treated as follows.

As shown in FIG. 2, when the plastic waste is put into the hopper 1, the plastic waste is transferred by the conveyor belt 2 in the first transfer path 13 toward the biaxial shearing machine 16. . When this plastic waste passes through the intermediate position of the first transfer path 13,
The microwave heating treatment is performed by the microwave heating treatment device 18. That is, the microwave oscillated from the microwave oscillator 4 is guided to the intermediate position of the first transfer path 13 by the waveguide 5 and irradiated to the plastic waste passing through the intermediate position. As a result, the plastic waste is microwave heated. By this microwave heating treatment, the plastic waste is dried (removed of water adhering or absorbed in the plastic waste) and is heated to a high temperature.

Thereafter, the plastic waste subjected to the microwave heating treatment is further transported by the conveyor belt 2 and then supplied to the biaxial shearing blade 8 via the biaxial shearing machine hopper 7, and this biaxial shearing blade 8 is supplied with the plastic waste. It is sheared and crushed by the blade 8.

The plastic waste that has been sheared and crushed into crushed pieces falls onto a conveyor belt 10, is transported by the conveyor belt 10, is taken out of the apparatus through a crushed piece take-out port 12, and is collected. Thus, the plastic waste crushing process is completed.

As described above, the microwave heating type biaxial shear crusher is characterized in that the microwave heating treatment is performed before the crushing treatment is performed. (Here, plastic waste) is heated, and the calorific value (W), that is, the temperature rise, is expressed by the following equation, as shown by the following equation, the dielectric constant ε and the dielectric loss tangent tanδ, And the microwave power E and frequency ω. W = E ²・ ω ・ ε ・ tanδ

The effects of the present microwave heating type biaxial shear crusher will now be described with reference to FIGS. 3 and 4. FIG. FIG. 3 is a two-dimensional dielectric characteristic map of various materials (organic materials such as plastic, wood, rubber, and other materials), and FIG. 4 is a graph showing transverse shear stress of a glass fiber reinforced composite resin (hereinafter referred to as FRP). It is a graph which shows temperature dependence.

As is apparent from the above equation, the heating effect of the microwave heating depends on the dielectric properties of the object to be heat-treated, that is, the relative dielectric constant and the dielectric loss tangent, and as shown in FIG. And polyester-based FRP is a material that is easily heated by microwaves. That is, it can be seen that microwave heating is suitable for the heat treatment of the plastic waste (thermoplastic or thermosetting resin alone or FRP). In addition, since moisture adhering or adsorbing to plastic waste exhibits particularly large dielectric properties, extremely high microwave heating efficiency can be expected.

Therefore, the microwave heating by the microwave heating apparatus 18 allows the plastic waste to be heated (drying and high-temperature processing) more quickly than the external heater heating method which can be considered as another heating source. It can be carried out. That is, since the plastic waste itself and the moisture adhering to or absorbed by the plastic waste are efficiently heated by the microwave heating, the moisture can be quickly removed from the plastic waste in an air atmosphere, and the plastic waste can be removed. The temperature of an object can be quickly raised to a high temperature.

By performing the above-described drying treatment, there is a possibility that problems such as promoting corrosion of the biaxial shearing blade 8 and peripheral components due to moisture adhering to or absorbed by the plastic waste may occur. There is no. In addition, by performing the above-described high temperature treatment, the elastic modulus of the resin is generally lower than that at the time of the atmospheric temperature. Therefore, in the subsequent crushing treatment by the biaxial shearing machine 16, the plastic material does not require too much breaking energy. Waste can be crushed. For example, in the above-mentioned epoxy-based FRP, phenol-based FRP, and polyester-based FRP, as shown in FIG. 4, in any sample (thickness: 1 m, 2 m, 3 m), the shear stress increases as the temperature increases. Is declining. Therefore, the drive motor 9 of the biaxial shearing machine 14 can have a low capacity, and energy can be saved.

The crushing method is as follows.
In addition to the biaxial shear crushing method using crushing, there is a rotary crushing method using a roll press, etc., but the decrease in the elastic modulus of plastic waste due to heat treatment (high temperature treatment) is caused by the fracture energy in biaxial shear crushing. It is particularly effective in reducing the amount of slag.

In particular, in the case of FRP, a large internal stress is generated between the glass fiber and the resin due to the rapid heat treatment (high temperature treatment).
This also effectively acts on fragmentation and fine crushing of FRP by biaxial shear crushing, and the breaking energy required for shear crushing further decreases.

Further, since rapid heat treatment can be performed by microwave heating by the microwave heat treatment device 18, this heat treatment and the subsequent biaxial shearing machine 16
And the crushing process can be performed continuously, and crushed pieces of plastic waste can be continuously and efficiently obtained.

Further, the microwave heating treatment device 18 comprises:
The installation space for the heat treatment apparatus may be smaller than that of the above-described external heater heating method or the like.

Further, since the microwave shielding curtains 11a and 11b are provided in the base end portion and the distal end portion of the first transfer path 13, these microwave shielding curtains 11a and 11b are provided.
a, 11b and the first transfer path 13 surround the microwave irradiating section to prevent microwave leakage, and prevent the microwave from affecting the surroundings.
Furthermore, since the microwave shielding curtain 11c is also provided in the crushed piece take-out port 14, when microwaves leak from the microwave shielding curtain 11b, the microwaves are transmitted to the microwave shielding curtain 11a. It can be shielded by the case 15 and the second transfer path 14.

[0037]

As described above in detail with the embodiments of the present invention, the waste crushing method of the present invention is a method of crushing waste which is easily heated by microwaves. The method is characterized in that crushing is performed after microwave irradiation is performed by irradiating a wave.

Further, the waste crushing apparatus of the present invention is a waste crushing apparatus which is easily microwave-heated, comprising: crushing means for crushing the waste; and transfer means for transferring the waste to the crushing means. And microwave heating means for irradiating the waste transferred by the transfer means with microwaves to perform microwave heating processing.

Further, the waste crushing device of the present invention is characterized in that in the crushing device, the crushing means is a biaxial shearing machine.

Therefore, according to the waste crushing method or the crushing apparatus, the heat treatment (drying treatment and high temperature treatment) of the waste can be quickly performed by microwave heating. In other words, the waste itself and the moisture adhering to or absorbed by the waste are efficiently heated by the microwave heating, so that the moisture can be quickly removed from the waste and the temperature of the waste can be quickly raised to a high temperature. Can be raised. Then, by performing such a drying treatment, there is no possibility that a problem such as promoting corrosion of the device (such as a blade for biaxial shearing) due to moisture adhering or adsorbed to the waste occurs. In addition, since such high temperature treatment reduces the elastic modulus of the resin when the waste is plastic waste, it is particularly effective in reducing the breaking energy in biaxial shear crushing, thereby conserving energy. Can be achieved. And plastic waste is FRP
In the case of (1), rapid heat treatment (high temperature treatment) causes a large internal stress between the glass fiber and the resin, thereby further reducing the breaking energy required for shear crushing.

Further, since rapid heat treatment can be performed by microwave heating, this heat treatment and subsequent crushing can be performed continuously, and crushed pieces of waste can be continuously and efficiently produced. Obtainable. Furthermore, the installation space of the microwave heating processing means may be smaller than that of an external heater heating method or the like.

Further, the waste crushing apparatus of the present invention is characterized in that, in any one of the crushing apparatuses described above, at least a microwave irradiating section to the waste by the microwave heating means is provided around the microwave irradiating section. And microwave shielding means surrounding the microwave.

Therefore, according to this waste crushing apparatus,
Microwave leakage can be prevented by the microwave shielding means, and the influence of the microwave on the surroundings can be prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a microwave heating type biaxial shear crushing apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a schematic configuration inside the microwave heating type biaxial shear crushing apparatus.

FIG. 3 is a two-dimensional dielectric characteristic map of various materials (organic materials such as plastic, wood, rubber, and other materials).

FIG. 4 is a graph showing the temperature dependence of the transverse shear stress of FRP.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Hopper 2, 10 Conveyor belt 3 Microwave power supply 4 Microwave oscillator 5 Waveguide 6 Fan 7 Biaxial shearing machine hopper 8 Biaxial shearing blade 9 Drive motor 11a, 11b, 11c Microwave shielding curtain 12 Fragment removal Outlet 13 First transfer path 14 Second transfer path 15 Case 16 Biaxial shearing machine 18 Microwave heating treatment device

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI // B29K 105: 26

Claims (4)

[Claims] 1. A method for crushing waste which is easily heated by microwaves, comprising irradiating the waste with microwaves and performing a microwave heating treatment, and then performing a crushing treatment. Crushing method. 2. A device for crushing waste which is easily microwave-heated, comprising: crushing means for crushing said waste; transfer means for transferring said waste to said crushing means; and said transfer means transferred by said transfer means. A microwave crushing device, comprising: microwave heating means for irradiating microwaves to microwaves to perform microwave heating processing. 3. The apparatus for crushing waste according to claim 2, wherein said crushing means is a twin-screw shearing machine. 4. The waste crushing device according to claim 2, wherein at least a microwave irradiating section of the waste by the microwave heating means surrounds the microwave irradiating section. An apparatus for crushing waste, comprising microwave shielding means for shielding the microwave.