JP2000061356A - Plastic sorting apparatus and plastic sorting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plastic sorting apparatus and a plastic sorting method for sorting crushed refuse of plastic fragments to be sorted into respective types. SOLUTION: A triboelectrification apparatus 3 is constituted of a first stirring container 15 having an intake 14 for plastic fragments, first stirring blades 17 installed in the inside of the first stirring container 15 in a freely rotatable manner a second stirring container 21 integrally formed in a lower part of the first stirring container 15 and having an upper part in one side communicated with an outlet part 19 of the first stirring container 15 and a dropping port 20 formed in a lower part in the other side for dropping plastic fragments 1 to an electrostatic separation part, screw type second stirring blades 23 installed in the inside of the second stirring container 21 in a freely rotatable manner, so that precise separation can be carried out in the electrostatic separation part by charging the plastic fragments 1 with sufficient static electricity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic sorting apparatus and a plastic sorting method for sorting sorted crushed waste consisting of plastic pieces by type.

[0002]

2. Description of the Related Art In recent years, recycling of waste has been rapidly promoted. By the way, plastics consumed as raw materials for plastic products include vinyl chloride resin (hereinafter referred to as “PVC”) and polyethylene resin (hereinafter referred to as “P”).
"E"), polypropylene resin (hereinafter "PP")
), Polystyrene resin (hereinafter referred to as "PS") and methacrylic resin [acrylic resin] (hereinafter referred to as "P").
It is considered that about 80% of the whole is referred to as "MMA") and that the above-mentioned resins account for most of the waste plastics recovered. In addition, polyethylene terephthalate resin (hereinafter referred to as “PET”) used as so-called PET bottles is being collected independently. When recycling these resins, it is important to sort them by type of resin.

As a technique for selecting the crushed plastic pieces, there is a plastic selecting device, and the plastic selecting device will be described with reference to FIG. In this plastic sorting device, when plastics 1 of different types of resin, which are different types of crushed wastes, are loaded into the hopper 2, the plastic pieces 1 are loaded into the frictional charging device 3 from the outlet of the hopper 2. The plastic piece 1 is agitated and frictionally charged by the frictional charging device 3, and then sprayed on the upper surface of the metal drum electrode 5. The metal drum electrode 5 is rotated about a horizontal axis in a predetermined direction and is grounded.

A circular plate-shaped high-voltage electrode 6 is arranged diagonally above the metal drum electrode 5 in the direction of rotation, and a cathode of a high-voltage power supply device 7 is connected to the high-voltage electrode 6, and a high-voltage power supply device is connected. The anode of 7 is grounded. By this connection, a rotary ground electrode is formed by the metal drum electrode 5,
An electrostatic field for sorting is formed between the high voltage electrode 6 and the metal drum electrode 5.

Below the metal drum electrode 5, a first separation container 8 and a second separation container 9 which are open upward are sequentially arranged on the upstream side in the rotation direction. Further, a brush 10 for scraping off the plastic piece 1 adhering to the peripheral surface of the metal drum electrode 5 is arranged on the outer peripheral portion of the metal drum electrode 5.

The operation of the above configuration will be described. A plurality of types of plastic pieces 1 are charged into the frictional charging device 3 from the hopper 2, and different types of plastics pieces 1 are agitated and frictionally charged in one cylinder of the frictional charging device 3 to be charged. . Then, the charged plastic piece 1 is scattered on the metal drum electrode 5, and the plastic piece 1 charged with a negative electric charge by the frictional charging device 3 repels the metal drum electrode 5 and is attracted to the high-voltage electrode 6, It falls into the first separation container 8. Further, the plastic piece 1 having a positive charge opposite to that of the metal drum electrode 5 is adsorbed on the surface of the metal drum electrode 5 and dropped into the second separation container 9 by the rotation of the metal drum electrode 5, or the brush 10 is used. Is scraped off from the surface of the metal drum electrode 5 and separated,
It falls into the second separation container 9.

[0007]

In the above-mentioned frictional charging device 3, the plastic pieces 1 made of a plurality of different resinous plastics, which have been charged into the hopper 2, are stirred in one cylinder for frictional charging. However, depending on the size of the plastic piece 1, it may reach the falling port of the cylinder faster than other plastic pieces 1 and fall, and in this case, the plastic piece 1 has a sufficient charge amount (charge voltage). Was not given, and the metal drum electrode 5 and the high voltage electrode 6 may not be accurately separated.

In order to prevent this, it is conceivable to make the container of the triboelectrification device 3 large in size, but this requires a large space for installing the triboelectrification device 3. Therefore, an object of the present invention is to provide a plastic sorting apparatus and a plastic sorting method that can solve the above problems.

[0009]

A means for solving the problems in the present invention is a frictional charging device for stirring and frictionally charging a plurality of crushed plastic pieces, and a frictional charging device disposed below the frictional charging device. A plastic sorting device having an electrostatic separation unit for separating the separated plastic pieces by using a charge amount, wherein the frictional charging device includes an upper first stirring container and a first stirring container. A first stirring blade rotatably mounted around the vertical axis, and a first stirring blade disposed at the lower portion of the first stirring container, one side of which communicates with the outlet of the first stirring container and the other side of which is provided with plastic for the electrostatic separation unit. A second stirring container provided with a dropping port for dropping the piece, and a screw-type second stirring blade rotatably mounted in the second stirring container so as to be rotatable around the horizontal axis.

The first stirring vessel, the first stirring blade,
The second stirring container and the second stirring blade are made of metal.
In the above configuration, a plurality of kinds of plastic pieces are stirred in the first stirring container by the first stirring blade rotatable about the vertical axis, and subsequently, the horizontal axis is set in the second stirring container communicating with the outlet of the first stirring container. Stir with a screw-type second stirring blade that is rotatable around, and quantitatively drop the plastic piece into the electrostatic separation unit arranged below the drop opening of the second stirring container with the second stirring blade,
The plastic pieces frictionally charged by the frictional charging device are separated by the electrostatic separation unit by using the charge amount and collected separately.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. First, a plastic sorting apparatus for carrying out the plastic sorting method according to the embodiment of the present invention will be described with reference to FIG. The difference between the plastic sorting apparatus S according to the embodiment of the present invention and the conventional plastic sorting apparatus is the configuration of the frictional charging device 3.

The plastic sorting apparatus S according to the embodiment of the present invention is a hopper 2 for feeding a plurality of different resin-based plastic pieces (sorted crushed dust) 1 in a mixed state.
And a frictional charging device 3 disposed on the outlet 2a side of the hopper 2 for frictionally charging the plastic piece 1 by stirring, and a plurality of types of frictionally charged plastics disposed below the frictional charging device 3. An electrostatic separation part G for electrostatically separating the piece 1, and a first separation container 8 and a second separation container 9 for collecting the plastic pieces 1 electrostatically separated by the electrostatic separation part G by type. Is equipped with.

As shown in FIG. 2, the frictional charging device 3 is
Is an upper first stirring container 15 having an intake port 14 arranged at the outlet 2a of the hopper 2, and a first stirring blade 1 rotatably mounted in the first stirring container 15 around a vertical axis member 16.
7, a first drive motor 18 for rotating the vertical axis member 16 and a lower part of the first stirring container 15 that is integrally formed and one side upper part communicates with the outlet 19 of the first stirring container 15. A second stirring container 2 having a drop port 20 for dropping the plastic piece 1 to the electrostatic separation part G at the lower part of the other side.
1, a screw type second stirring blade 23 rotatably mounted in the second stirring container 21 around the horizontal shaft member 22, and a second drive motor 24 for rotating the horizontal shaft member 22. , The first stirring vessel 15, the first stirring blade 17,
The second stirring container 21 and the second stirring blade 23 are made of metal.

Next, based on FIG. 1, the electrostatic separation unit G
The configuration of will be described. This electrostatic separation part G is provided with the metal drum electrode 5 arranged below the drop port 20 of the second stirring container 21.
A high voltage electrode 6 arranged obliquely above the metal drum electrode 5, and a brush 10 arranged below the metal drum electrode 5 for scraping off the plastic piece 1 adhering to the peripheral surface of the metal drum electrode 5. It consists of and. In addition,
The metal drum electrode 5 is configured to be rotatable about a horizontal axis in a predetermined direction and is grounded. The cathode of the high-voltage power supply device 7 is connected to the high-voltage electrode 6, and the anode of the high-voltage power supply device 7 is grounded. By this connection, a rotary ground electrode is formed by the metal drum electrode 5, and an electrostatic field for selection is formed between the high voltage electrode 6 and the metal drum electrode 5.

The first separation container 8 and the second separation container 9 are disposed below the metal drum electrode 5 and below the metal drum electrode 5.
The first separation container 8 and the second separation container 9 are open upward.

Next, the plastic sorting apparatus S having the above-mentioned structure
The method of sorting plastics will be described. A plurality of types of plastic pieces 1 are mixed and put into the first stirring container 15 of the frictional charging device 3 from the hopper 2, and the first driving motor 18 drives the first stirring blade 17 to rotate and preliminarily stir. It is charged with a certain amount of charge. Then, the plastic piece 1 is the outlet portion 1 of the first stirring container 15.
9 into the second stirring container 21 and the second drive motor 2
4 is driven by the screw type second stirring blade 23 to obtain a sufficient amount of charge and is conveyed toward the drop port 20 of the second stirring container 21.

By the way, even if there is a plastic piece 1 that tends to drop into the second stirring container 21 faster than the other plastic pieces 1 depending on the size of the plastic piece 1, other plastic pieces 1 will remain in the second stirring container 21. A piece of plastic
It is surely stirred to obtain a sufficient amount of charge. Then, the sufficiently charged plastic piece 1 is sprayed by the screw type second stirring blade 23 from the dropping port 20 onto the metal drum electrode 5 in a fixed amount, and the frictional charging device 3 charges the negatively charged plastic piece 1. 1 repels the metal drum electrode 5, is attracted to the high-voltage electrode 6, and falls into the first separation container 8. Further, the plastic piece 1 having a positive charge opposite to that of the metal drum electrode 5 is adsorbed on the surface of the metal drum electrode 5 and dropped into the second separation container 9 by the rotation of the metal drum electrode 5, or the brush 10 is used. As a result, the metal drum electrode 5 is scraped off from the surface and dropped into the second separation container 9. In this way, even if a plurality of types of plastic pieces 1 are mixed, it is possible to separate or collect specific plastic pieces 1 for each charge amount (by type).

As described above, according to the embodiment of the present invention, the plural kinds of plastic pieces 1 are put into the first stirring container 15 of the frictional charging device 3 from the hopper 2 and the first stirring blades 1 are provided.
Pre-mixed with 7 and charged, plastic piece 1
From the outlet portion 19 of the first stirring container 15 to the second stirring container 2
1 and is stirred by the screw-type second stirring blade 23 to obtain a sufficient amount of charge, and then conveyed toward the drop port 20 of the second stirring container 21. The plastic piece 1 can be separated and tends to drop into the second stirring container 21 faster than other plastic pieces 1 depending on the size of the plastic piece 1.
Even if there is, the plastic piece 1 is surely stirred with the other plastic piece 1 in the second stirring container 21 to obtain a sufficient amount of charge, and the sufficiently charged plastic piece 1 is fed by the screw type second stirring blade 23. Since it is sprayed quantitatively from the drop port 20 onto the metal drum electrode 5, the electrostatic separation part G is kept stable.
Separation of the plastic piece 1 can be carried out.

Further, the first stirring container 15 and the first stirring blade 1
7. Since the second agitating vessel 21 and the second agitating blade 23 are made of metal, dirt and damage are less likely to occur, so even if the plastic piece 1 is crushed waste to be sorted, it can withstand long-term use and be damaged. Thus, it is possible to prevent the polarity of the plastic piece 1 from being adversely affected when it is frictionally charged.

[0020]

As is apparent from the above description, according to the present invention, the triboelectrification charging apparatus is provided with the upper first stirring container and the first stirring blade which is installed in the first stirring container so as to be rotatable about the vertical axis. A second stirring container provided at the lower part of the first stirring container, one side of which communicates with the outlet of the first stirring container and the other side of which is provided with a drop opening for dropping the plastic piece into the electrostatic separation unit, Since this second stirring vessel is equipped with a screw-type second stirring blade rotatably installed around the horizontal axis, after stirring a plurality of types of plastic pieces with the first stirring blade, the second stirring blade is used. Depending on the size of the plastic piece, the plastic piece 1 may drop into the second stirring container faster than the other plastic pieces 1 due to the stirring.
A sufficient amount of charge is given to, and the electrostatic separation unit can separate accurately by type of plastic piece (by amount of charge).
The charged plastic pieces quantitatively fall on the electrostatic separation unit by the screw type second stirring blade, so that the separation of the plastic pieces in the electrostatic separation unit can be performed in a stable state.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing an overall configuration of a plastic sorting apparatus showing an embodiment of the present invention.

FIG. 2 is a sectional view showing a detailed configuration of the frictional charging device.

[Explanation of symbols]

1 plastic piece 2 hoppers 3 Friction charging device 5 Metal drum electrode 6 High voltage electrode 8 First separation container 9 Second separation container 14 Intake 15 First stirring container 16 Vertical axis member 17 First stirring blade 18 First drive motor 19 Exit 20 Drop mouth 21 Second stirring container 22 Horizontal member 23 Second stirring blade 24 Second drive motor G electrostatic separation unit S plastic sorter

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Hidehiko Maehata             1-89 South Kohoku, Suminoe-ku, Osaka-shi, Osaka             Issue Hitachi Shipbuilding Co., Ltd. F-term (reference) 4D054 GA01 GA09 GA10 GB01 GB09

Claims (3)

[Claims] 1. A triboelectrification device for stirring and frictionally charging a plurality of crushed plastic pieces, and a triboelectrified plastic piece disposed below the triboelectrification apparatus, which is separated by utilizing the amount of charge. A plastic sorting apparatus having an electrostatic separation unit for performing the above-mentioned triboelectrification charging apparatus, wherein the triboelectrification apparatus includes a first stirring container on an upper side, and a first stirring container which is rotatably installed around the vertical axis. A stirring blade and a second drop port which is arranged at a lower portion of the first stirring container and has one side communicating with the outlet of the first stirring container and the other side provided with a drop opening for dropping the plastic piece to the electrostatic separation unit. A plastic sorting device comprising: a stirring container; and a screw-type second stirring blade that is installed in the second stirring container so as to be rotatable about the horizontal axis. 2. The plastic sorting apparatus according to claim 1, wherein the first stirring vessel, the first stirring blade, the second stirring vessel, and the second stirring blade are made of metal. 3. A plurality of kinds of plastic pieces are stirred in a first stirring vessel with a first stirring blade rotatable about a vertical axis, and subsequently,
The second stirring vessel communicating with the outlet of the first stirring vessel is stirred by a screw-type second stirring blade rotatable around the horizontal axis, and is placed below the drop opening of the second stirring vessel by the second stirring blade. A plastic characterized in that a plastic piece is quantitatively dropped into the electrostatic separation section, and the plastic piece frictionally charged by the frictional charging device is separated by the electrostatic separation section using the charge amount and collected separately. Sorting method.