JP2000342998A - Classifier for plastic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To separate/recover plastic pieces correctly by using a moving means which moves the partition wall of a recovery part toward/from a drum electrode without changing the voltage of electrodes and moving it horizontally to a falling position of each plastic piece associated with the polarity and the quantity of charge of the piece. SOLUTION: In a recovery part 26 arranged below a separating space 22, partition walls 30, 31 are made to approach/separate from a metal drum electrode 21, and a moving means for moving the walls 30, 31 horizontally to correspond to the falling position of plastic pieces 16 so that when the separation of the plastic pieces is inaccurate, the walls 30, 31 are moved to correspond to the falling position of the plastic pieces 16 to perform the separation correctly without changing voltage from a high voltage power source apparatus 24.

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 for sorting plastic pieces for each type by recycling.

[0002]

2. Description of the Related Art In recent years, while recycling of refuse has been rapidly promoted, there is a plastic sorting apparatus as shown in FIG. 6 as a technique for sorting crushed plastic pieces. The plastic sorting device is disposed below a hopper 2 into which a plurality of types of plastic pieces 1 are charged, and a frictional charging device 3 for charging the plastic pieces 1 to a polarity and a charge amount for each type; 3 and an electrostatic separation device G for separating the charged plastic pieces 1 according to the polarity and the charge amount.

The electrostatic separation device G includes a metal drum electrode 5 disposed below the chute 3b of the frictional charging device 3, a high voltage electrode 6 disposed obliquely above the metal drum electrode 5, A brush 10 for scraping off the plastic piece 1 attached to the peripheral surface of the metal drum electrode 5; The metal drum electrode 5 has a horizontal axis 5a.
The high voltage electrode 6 is connected to, for example, a cathode of a high voltage power supply 7, and the anode of the high voltage power supply 7 is grounded.
With this connection, a sorting electrostatic field is formed between the high-voltage electrode 6 and the metal drum electrode 5.

[0004] A first separation container 8 for recovering the plastic pieces 1 having passed through the sorting electrostatic field by type.
And the second separation container 9 is disposed and fixed below the metal drum electrode 5. In the above-mentioned plastic sorting apparatus, when the plastic 1 is put into the hopper 2, the plastic 1 is put into the friction charging device 3 from the hopper 2 and is stirred, and the plastic 1 has a predetermined polarity and a predetermined charge according to the charging sequence according to the kind. It is triboelectrically charged. afterwards,
It falls to the electrostatic separation device G, passes through the sorting electrostatic field, and is collected in separate containers 8 and 9 for each polarity and charge amount.

[0005]

By the way, in the above-mentioned plastic sorting apparatus, the plastics 1 are frictionally charged to a predetermined polarity and charge amount by stirring the plastics 1 in the frictional charging device 3 to form a charging line corresponding to the plastics 1. 8,
9 are collected by type. However, if the voltage applied to the high-voltage electrode 6 is too low, the electrostatic field for sorting is weak, and the separation and recovery of the plastic 1 passing therethrough cannot be performed reliably. Therefore, in order to reliably separate and recover the plastic 1 into the first separation container 8 and the second separation container 9, a strong sorting electrostatic field is required by the high-voltage electrode 6. For that purpose, a very high voltage must be applied to the high-voltage electrode 6, and the high-voltage electrode 6 corresponding to the applied voltage has been required.

Therefore, an object of the present invention is to provide a plastic sorting apparatus capable of solving the above-mentioned problems.

[0007]

The object of the present invention is to provide a friction charging device for stirring and frictionally charging a plurality of types of crushed plastic pieces, and a charging device disposed below the friction charging device. An electrostatic separation unit is provided for electrostatically separating and sorting the plastic pieces according to the polarity and the charge amount thereof.The electrostatic separation unit includes a drum electrode rotatable around a predetermined horizontal axis, The drum electrode is provided with a counter electrode disposed via a separation space serving as a sorting electrostatic field, and a plastic piece having a polarity and a charge amount for each type in the frictional charging device passes through the separation space. A collecting section is provided below the separating space for separately collecting the plastic pieces passing therethrough, and the collecting section includes a plurality of collecting chambers and a collecting section. Each of the department A partition wall for partitioning the storage chamber is provided, and the partition wall is configured to be movable and adjustable in the horizontal direction so as to approach and separate from the drum electrode. Moving means for moving in the horizontal direction is provided.

In the above configuration, when the sorting of the plastic pieces is not accurately performed in the respective collecting chambers, the moving means is used to move the partition wall of the collecting section closer to or away from the drum electrode, and the polarity of each plastic piece is determined. It is moved in the horizontal direction according to the drop position according to the charge amount. In addition, a frictional charging device for stirring and frictionally charging a plurality of types of crushed plastic pieces, and an electrostatically separating plastic piece disposed below the frictional charging device according to its polarity and charge amount. And an electrostatic separation unit is provided for separation by a drum electrode rotatable around a predetermined horizontal axis and a separation space serving as a selection electrostatic field on the drum electrode. And a counter electrode that is disposed in such a manner that the plastic pieces having the polarity and the charge amount for each type in the frictional charging device are passed through the separation space to be separated and collected, and are provided below the separation space. A collecting unit for separately collecting the plastic pieces separated by passing through the collecting unit, the collecting unit includes a plurality of collecting chambers and partition walls for partitioning the collecting chambers of the collecting unit; Is the dora Swing means configured to be swingable around a support shaft parallel to the horizontal axis direction of the electrode, and to swing the partition wall around the support shaft according to the drop position according to the polarity and charge amount of each plastic piece. Is provided.

In the above configuration, when the sorting of the plastic pieces is not accurately performed in each of the collecting chambers, the swing means is used to move the partition wall of the collecting section closer to and away from the drum electrode, and the polarity of each plastic piece is changed. -Swing around the spindle according to the drop position according to the charge amount.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. First, based on FIGS. 1 to 4, the plastic sorting device 15 according to the first embodiment of the present invention will be described.
Will be described. The plastic sorting device 15 according to the first embodiment of the present invention separates and collects a plurality of different types of resin-based plastic pieces (sorted and crushed refuse) 16 for each plastic piece 16. (Polyethylene) and PP (polypropylene) are separated and recovered. In addition, PE and PP used beforehand crushed to 5 mm or less are used.

That is, a frictional charging device 17 for frictionally charging a PVC (vinyl chloride), which will be described later, is mixed with PE and PP, and a discharge port communicated with an openable and closable outlet 18 of the frictional charging device 17. A chute 19 and a predetermined horizontal shaft 2 disposed near and below the discharge chute 19;
A metal drum electrode 21 which is rotatable around zero and is grounded; and a high voltage electrode which is disposed diagonally above the metal drum electrode 21 and is disposed via a separation space 22 which serves as a sorting electrostatic field. (Opposite electrode) 23, a high-voltage power supply 24 for connecting a cathode to the high-voltage electrode 23 and grounding the positive electrode to load the high-voltage electrode 23, and a peripheral surface of the metal drum electrode 21. Plastic piece 1 placed at the bottom and attached to metal drum electrode 21
A brush 25 for scraping off the brush 6 is provided.
The outlet 18 is provided with a shutter 18a for opening and closing the outlet 18 so as to be movable in the horizontal direction.

A collection section 26 is provided below the separation space 22 for separately collecting the plastic pieces 16 that have passed therethrough and have been separated for each polarity and charge amount.
The collection unit 26 includes a plurality (three in this case) of collection chambers 2.
7, 28, 29 and partition walls 30, 31 and front and rear walls 32 for partitioning the collection chambers 27, 28, 29. The partition walls 30, 31 are horizontally moved and adjusted so as to approach and separate from the metal drum electrode 21. It is freely configured.

As shown in FIGS. 2 and 3, there is provided a moving means 33 for moving each of the partition walls 30 and 31 in the horizontal direction according to the falling position according to the polarity and charge amount of each plastic piece 16. The moving means 33 includes a pair of partition walls 30 and 31 which are horizontally disposed such that the partition walls 30 and 31 approach and separate from the metal drum electrode 21, and which are separately attached to the respective partition walls 30 and 31 via fitting members 34. Guide 35
And a ball screw 37 screwed into a screw member 36 attached to the fitting member 34 of the guide 35, and a motor (not shown) for rotating the ball screw 37.

Further, a recycling device 39 for returning the PVC to the frictional charging device 17 via a return pipe 38 is attached to the collecting section 26. Further, although not shown, an image processing device for observing the electrostatic separation state of the plastic piece 16 is arranged at a predetermined location. By the way, the plastic pieces 16 to be sorted are placed in a frictional charging device 17.
, The plastic piece 16 is charged to either plus or minus according to the charging sequence. However, depending on the plastic piece 16 to be sorted, if the charging row is close and there is no material located in the middle of the charging row, this is added to the plastic piece 16 as friction material. In the present embodiment, the PVC is added as a friction material in order to select PE and PP. When PE, PP, and PVC are charged by stirring with the frictional charging device 17, the charging sequence becomes (+) PE <PP <P
VC (-).

Therefore, when selecting PE and PP, a mixed plastic of PE, PP, and PVC is charged into the frictional charging device 17 as the plastic piece 16 and agitated, so that each plastic piece 16 has a predetermined polarity and charging for each type. To be charged. That is, a charging sequence of (+) PE <PP <PVC is obtained. The plastic piece 16 thus charged
Is dropped onto the metal drum electrode 21 from the discharge port 18 through the discharge chute 19 with the shutter 18a opened. Then, the three types of plastic pieces 16 fall through the separation space 22 and fall into the collection unit 26 due to the rotation of the metal drum electrode 21. And plastic piece 16
Is charged to (+) when passing through the separation space 22, the PE is attracted to the high-voltage electrode 23 to which the cathode is connected, is collected in the collection chamber 29, and is collected.
Since C is charged to (−), it is attracted to the metal drum electrode 21 and collected in the collection chamber 27, or PVC attached to the metal drum electrode 21 is scraped off to the collection chamber 27 by the brush 25 and collected. Is done. Then, the PP located at the intermediate position of the charging line is collected in the collection chamber 28 between the collection chamber 27 and the collection chamber 29.

On the other hand, the electrostatic separation state of whether the PE is collected in the collection chamber 29, the PVC is collected in the collection chamber 27, and the PP is collected in the collection chamber 28 is observed with the image processing apparatus. I do. It is only necessary that the PE is separated and collected in the collection chamber 29, the PVC is collected in the collection chamber 27, and the PP is collected and collected in the collection chamber 28. Otherwise, without changing the load voltage of the high-voltage power supply 24, the plastic pieces are collected. The ball screw 37 is rotated by driving the motor in accordance with the polarity and the charge amount of the partition 16, and one or both of the partition walls 30, 31 are moved closer to or away from the metal drum electrode 21.
The positions of 8, 29 are adjusted to ensure that PVC, PP, and PE are collected in the collection chambers 27, 28, 29, respectively.

FIG. 4 shows the result of electrostatically separating the plastic pieces 16 with the applied voltage of 30 kv in the high voltage power supply 24. The recovery rate and purity of each of PVC, PP, and PE were 80% or more. The PVC used as the friction material is subjected to static elimination and cleaning and cleaning by the recycling device 39, and is fed back to the friction charging device 17 to be reused.

As described above, according to the first embodiment of the present invention, in the recovery section 26 disposed below the separation space 22, the partition walls 30, 31 are horizontally moved so as to approach and separate from the metal drum electrode 21. A moving means 33 is provided for moving the partition walls 30 and 31 in the horizontal direction according to the drop position according to the polarity and the amount of charge of each plastic piece 16, and the moving means 33 is provided. , Partition wall 3
0 and 31 are arranged in the horizontal direction so as to approach and separate from the metal drum electrode 21, and fitting members 34 are attached to the respective partition walls 30 and 31.
And a pair of guides 35 separately attached via a screw member 36 attached to the fitting member 34 of the guide 35
And a motor (not shown) for rotating the ball screw 37.
If the separation of the plastic pieces 16 is inaccurate, the partition 3
The motor is driven to move the ball screws 37 so that the plastic pieces 16 are moved in accordance with the drop position according to the polarity and charge amount of each plastic piece 16, and the partition walls 30 and 31 are moved closer to and away from the metal drum electrode 21. As a result, without changing the voltage from the high voltage power supply 24,
6 can be accurately separated.

Next, a second embodiment of the present invention will be described with reference to FIG. The plastic sorting device 15 according to the second embodiment of the present invention separates each of the partition walls 30 and 31 in the direction of the horizontal axis 20 of the drum electrode 21 according to the drop position according to the polarity and charge amount of each of the plastic pieces 16. Parallel support shaft 5
Each partition wall 30, 31 is configured to be swingable around zero.
Is provided with a swinging means 51 for swinging around the 50-axis in accordance with the falling position according to the polarity and charge amount of each plastic piece 16. This swing means 51
As shown in FIG. 5, the motor includes swing motors 52 and 53 attached to each support shaft 50, and a control device 54 for driving the swing motors 52 and 53. The other configuration is the same as that of the first embodiment, and the description is omitted.

In the above configuration, when the separation of the plastic pieces 16 is inaccurate, the motors 52 and 53 are moved so that the partition walls 30 and 31 are moved in accordance with the drop position according to the polarity and the charge amount of each plastic piece 16. Drive each spindle 50
Is rocked, and the partition walls 30 and 31 are
, The plastic pieces 16 can be accurately separated without changing the voltage from the high voltage power supply 24. Other functions and effects are the same as in the first embodiment, and a description thereof will be omitted.

In the above embodiments, the friction material is made of PVC which becomes (-) in the charging line. However, the present invention is not limited to this, and PS (polystyrene) which becomes (+) side is used.
Or PMMA (acrylic) may be used. In this case, P
P is adsorbed on the metal drum electrode 21 and collected in the collection chamber 27, PE is collected in the collection chamber 28, and PS or PM is collected.
The MA is collected in the collection chamber 29.

[0022]

As is evident from the above description, the present invention is provided with a collecting section below the separating space for separately collecting the plastic pieces separated through the separating space. Is provided with a plurality of collection chambers and partition walls for partitioning each collection chamber of the collection section, this partition wall is configured to be movable and adjustable in the horizontal direction so as to approach and separate from the drum electrode. Since a moving means is provided for moving in the horizontal direction according to the drop position according to the polarity and the charge amount, even if the sorting of the plastic pieces is not accurately performed in each collection chamber, the counter electrode of Without changing the voltage, using moving means to move the partition wall of the recovery unit closer to and away from the drum electrode,
Accurate separation and recovery can be achieved by moving the plastic pieces in the horizontal direction according to the drop position according to the polarity and charge amount.

Further, a collecting section is provided below the separating space for separately collecting the plastic pieces separated by passing through the separating space. The collecting section includes a plurality of collecting chambers and each collecting section of the collecting section. A partition wall for partitioning the chamber, the partition wall is configured to be swingable around a support axis parallel to the horizontal axis direction of the drum electrode, and the partition wall is placed at a drop position according to the polarity and charge amount of each plastic piece. A swinging means for swinging around the support shaft according to the requirement is provided, so that even if the sorting of the plastic pieces is not accurately performed in each of the collecting chambers, the partitioning wall of the collecting section is formed by the drum electrode. Using a rocking means to move closer to and away from the
By swinging around the support shaft according to the drop position according to the charge amount, accurate separation and collection can be performed.

[Brief description of the drawings]

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

FIG. 2 is a perspective view illustrating a configuration of a collection unit.

FIG. 3 is a cross-sectional view showing the configuration of the collection unit.

FIG. 4 is a graph showing the recovery rate and purity of each type of plastic piece.

FIG. 5 is a perspective view of a main part of a plastic sorting device according to a second embodiment of the present invention.

FIG. 6 is an overall configuration diagram of a conventional plastic sorting device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 15 Plastic sorting device 16 Plastic piece 17 Friction charging device 21 Metal drum electrode 22 Separation space 23 High voltage electrode 24 High voltage power supply 26 Recovery part 27 Recovery chamber 30 Partition wall 33 Moving means 50 Support shaft 51 Swing means 52 Swing motor 54 Controller

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Daisuke Tamakoshi 1-7-89 Minami Kohoku, Suminoe-ku, Osaka-shi, Osaka Inside Hitachi Zosen Corporation (72) Inventor Masanori Tsukahara 1-chome, Minami-Kohoku, Suminoe-ku, Osaka-shi, Osaka 7-89 Hitachi Zosen Corporation (72) Inventor Hidehiko Maehata 1-7-89 Minami Kohoku, Suminoe-ku, Osaka-shi, Osaka F-term in Hitachi Zosen Corporation 3F079 CA37 CC01 CC11 DA01 DA28 4D054 GA01 GA10 GB01 GB09 4F301 AA13 AA14 BA02 BA21 BA29 BE29 BF08 BF12 BF25 BF32

Claims (2)

[Claims] 1. A friction charging device for stirring and frictionally charging a plurality of types of crushed plastic pieces, and a charged plastic piece disposed below the friction charging device according to its polarity and charge amount. An electrostatic separation unit for electrostatic separation and sorting is provided. The electrostatic separation unit is provided with a drum electrode rotatable around a predetermined horizontal axis, and a separation electrode serving as a sorting electrostatic field on the drum electrode. A counter electrode disposed via a space, and a plastic sorting apparatus configured to separate and collect the plastic pieces having the polarity and charge amount for each type by the frictional charging apparatus by passing through the separation space. A collection unit is provided below the separation space for separately collecting the plastic pieces passing therethrough and separated, and the collection unit includes a plurality of collection chambers and collection chambers of the collection unit. Partitioning It is provided with a cut wall, and the partition wall is configured to be movable and adjustable in the horizontal direction so as to approach and separate from the drum electrode, and the partition wall is moved in the horizontal direction according to the drop position according to the polarity and charge amount of each plastic piece. A plastic sorting device provided with moving means for causing the plastic to be separated. 2. A friction charging device for stirring and frictionally charging a plurality of types of crushed plastic pieces, and a charged plastic piece disposed below the friction charging device according to its polarity and charge amount. An electrostatic separation unit for separating by electrostatic separation is provided. The electrostatic separation unit includes a drum electrode rotatable around a predetermined horizontal axis, and a separation electrode serving as a separation electrostatic field on the drum electrode. A counter electrode disposed via a space, and a plastic sorting apparatus configured to separate and collect the plastic pieces having the polarity and charge amount for each type by the frictional charging apparatus by passing through the separation space. A collection unit is provided below the separation space for separately collecting the plastic pieces that have passed therethrough. The collection unit includes a plurality of collection chambers and each collection chamber of the collection unit. Partitioning The partition wall is configured to be swingable around a support axis parallel to the horizontal axis direction of the drum electrode, and the partition wall is supported in accordance with a drop position according to the polarity and charge amount of each plastic piece. A plastic sorting device comprising a swinging means for swinging around an axis.