JPH05162136A - Method and device for volume-reduction treating plastic-foam waste material - Google Patents

Abstract

PURPOSE:To facilitate the volume reduction of a plastic-foam waste material, which has high throughput capacity and in which the resin of a volume reduction article discharged is not deteriorated, by simple facilities. CONSTITUTION:The title device is composed of an extruder 1 volume-reducing a plastic-foam waste material supplied, a crusher 2 communicating with the discharge opening of the extruder, transport pipes 3, 5 mounted for air- transporting a crushed substance discharged from the outlet side of the crusher to a cyclone 7 on a housing chamber 6 and an air blower 4.

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 reducing the volume of waste plastic foam so that it can be effectively reused.

[0002]

2. Description of the Related Art In recent years, various plastic foams such as polyolefin foams have been widely used. However, since the waste is bulky, it is incinerated or converted into fuel oil (see JP-A-63-178195).
The transportation cost to the recycling processing factory is very high. Therefore, in order to reduce the transportation cost, it has to be transported, disposed of, incinerated or reused after being reduced in volume. Conventionally, a method of defoaming and reducing the volume of a crosslinked polyethylene foam on a heated mixing roll has been proposed (see JP-B-55-47052). However, defoaming with a mixing roll is a manual work, and thus the workability is poor and the work is dangerous. Further, there are drawbacks such that the equipment cost of the mixing roll is high. Recently, a volume reduction method and apparatus for polyurethane foam and the like have been proposed (see Japanese Patent Laid-Open No. 2-144183). In this method, the waste material is crushed and then pressurized to 140 kg / cm ² or more to reduce the volume and solidify. However, it is not possible to reduce the volume of a material having high strength such as a cross-linked polyolefin foam by simply pressurizing, and 140 kg / cm 2
Excessive equipment is required to pressurize to more than ^two .
Further, a volume reduction device for waste plastics has been proposed, in which plastics are self-heated between a volume reduction cylinder and a taper shaft rotatably arranged in the volume reduction cylinder to reduce the volume (see: special feature). Kaihei 3-65284).

[0003]

However, this volume reducing device has a low throughput because it has a single shaft. Also, in order to reduce the volume of all forms of synthetic resin, the sillingu etc. have a unique and complicated shape, mechanical troubles easily occur, the manufacturing cost is high, and the discharged volume-reduced material accumulates heat. There was a problem such as deterioration of the resin. The present invention has been made in order to solve the above problems, and efficiently disposes of all kinds of plastic foam waste materials with labor-saving and simple equipment, and the volume-reduced waste materials are stored by heat storage. It is a main object to provide a method and a device capable of reducing the volume so as not to deteriorate.

[0004]

In order to achieve the above object, the volume reduction treatment method for a plastic foam waste material according to the present invention is carried out by introducing the plastic foam waste material into an extruder and extruding to reduce the volume. It is characterized in that after crushing after discharge, the crushed material is pressure-fed to the storage chamber. The extruder is preferably a twin-screw extruder in terms of processing capacity. Further, the apparatus for reducing the volume of plastic foam waste material according to the present invention includes an extruder for reducing the volume of the supplied plastic foam waste material, a crusher connected to the outlet side of the extruder, and a discharge machine from the outlet side of the crusher. It is characterized by comprising a transport pipe and a blower provided for pressure-feeding the crushed material to the storage chamber. The extruder comprises a cylinder, two screws rotatably provided in the cylinder, and a motor for rotating the screw.
From the standpoint of processing capacity, it is preferable that the taper-shaped volume reducing portion whose cross-sectional area increases in the extrusion direction has a structure provided at the tip of the screw.

[0005]

Embodiments of the present invention will be described below with reference to the drawings. However, the following examples illustrate a volume reducing device for embodying the technical idea of the present invention,
The structure is not limited to the following. FIG. 1 shows an embodiment of the present invention. In the figure, 1 is an extruder for reducing the volume of the supplied plastic foam waste material, and 2 is a crusher connected to the discharge port of the extruder. The crusher 2
A normal crusher can be used, and its structure is not particularly limited. To facilitate the crushing of the waste material of the reduced volume sheet or lump, the rotary members with blade plates are opposed to each other, and the waste material is placed between the rotary members. You can also use a rotary crusher of the type that draws in and crushes, but combining a bladed rotor and a fixed blade plate,
It is preferable that the volume-reduced waste material can be crushed to a particle size of 20 mm or less, particularly preferably 10 mm or less. Screening of the particle size of the pulverized product may be appropriately performed. This is because if the particle size of the waste material exceeds 20 mm, pneumatic transportation becomes difficult and an excessive blower is required. The lower outlet of the crusher 2 is connected to an inlet of a blower 4 via a transport pipe 3, and the outlet of the blower 4 is connected via a transport pipe 5 to a cyclone 7 on an upper opening of a storage chamber 6. Have been contacted. The material of the transport pipes 3 and 5 and the storage chamber 6 is not particularly limited, and metal or plastic such as vinyl chloride is appropriately selected. An embodiment of the extruder shown in the schematic sectional view of FIG. 2 and the side view of the discharge side of FIG. 3 is a cylinder 8 and two screws 9 and 10 rotatably provided in the cylinder 8. It is composed of a motor 11 for rotating the screw of. The cylinder 8 has a shape in which two tubes having the same diameter are partially joined. The rear portion of the cylinder 8 is opened upward and is provided with an inlet 12 for waste plastic foam. Inside the cylinder 8, two screws 9 and 10 are arranged side by side. The rear end of the screw 10 is connected to a motor 11 and driven to rotate. The two screws 9 and 10 rotate inward via the gear 13. A spiral fin 14 is provided on the surface of the screw. By rotating the spiral fin 14 inward, the waste plastic foam material introduced from the inlet 12 is carried between the two screws, cut into small pieces, and pumped. The gap between the screw and the cylinder is almost parallel, and small pieces of foam are pumped forward.

The fins 14 of the two screws are designed to approach 0 to 1.6 mm, for example.
If the gap between the fins exceeds 1.6 mm, the cutting effect is reduced. At the tip of the screw, the volume reduction part 15
And 16 are provided and are formed in a taper shape whose cross-sectional area increases toward the tip direction, and the gap with the cylinder 8 is narrowed, so that the plastic foam is rubbed to cause self-heating to reduce the volume and remove the volume. It has the feature that it can foam. The gap between the cylinder 8 and the maximum diameter portions of the volume reducing portions 15 and 16 is preferably 1 to 5 mm. If the gap exceeds 5 mm,
Insufficient self-heating. By providing grooves or fins (not shown) in the volume reducing portions 15 and 16, self-heating can be more efficiently generated. In the above extruder, when the foam waste material is poorly wound between the screws, the fins on the screw surface are provided between the fins to provide a convex shape substantially parallel to the screw axis, thereby improving the foam waste material winding. be able to. Since the extruder of the volume reduction processing apparatus for the plastic foam waste material of the present invention causes the plastic foam to self-heat to reduce the volume and defoam,
The cylinder 8 does not necessarily need a heating means such as a heater. However, if self-heating is insufficient depending on the type of resin, a heating means can be appropriately provided on the outer surface of the cylinder 8. An electric heater is preferable as the heating means. On the other hand, when self-heating is too high and the resin deteriorates, measures such as reducing the amount of plastic foam input and installing a water cooling jacket on the outer surface of the cylinder are taken. When an excessive load is caused by excessive charging, the screw can be reversed to return the injected plastic foam to the charging port 12.

The extruder of the volume reduction apparatus of the present invention defoams, reduces the volume of the discarded plastic foam, and discharges it. The discarded plastic foam is supplied from the supply port 12 onto the screws 9 and 10. The plastic foam waste material fed onto the screws 9 and 10 is rotated by the fins 14 inward,
It is fed up between two screws, cut into pieces and pumped forward. The waste plastic foam that has been pressure-fed to the volume reducing portions 15 and 16 self-heats due to the frictional heat between the cylinder 8 and the volume reducing portions 15 and 16. The waste plastic foam self-heats at this portion because the rotating plastic reducers 15 and 16 press the waste plastic foam inside the cylinder 8 and rub the waste plastic foam under pressure. The waste plastic foam reduced in volume by the volume reducing parts 15 and 16 is discharged from the tip of the cylinder 8. The discharged waste material enters the crusher 2, where the sheet-like waste material is forcibly drawn in, preferably 20 mm or less,
It is particularly preferably ground to a size of 10 mm or less. The pulverized material in the pulverizer 2 is forcibly pulled out by the vacuum action of the blower 4, and the cyclone 7 is passed through the transport pipes 3 and 5.
The air is discharged and the crushed material falls into the storage chamber 6. The volume reducing device of the present invention can be applied to any plastic foam, but when it is applied to a polyolefin foam having high strength, especially a crosslinked polyethylene foam, the effect of the present invention is remarkable. Further, the shape of the plastic foam waste material can be any shape such as a block shape, a square shape, a rod shape, a sheet shape, and a punching waste, as long as it is a size that fits into the charging port.

[0008]

As described above, since the extruder of the volume reduction processing apparatus for the waste plastic foam material of the present invention has the twin screw having the tapered volume reduction portion at the tip, the volume reduction is performed. High processing capacity, plastic foam is efficiently wound into a twin screw and cut into small pieces.
Defoamed and reduced in volume. As long as it is a plastic foam, not only polyurethane foam, but also polyolefin foam with high strength, for example, crosslinked polyethylene foam,
Volume can be reduced efficiently. Further, since the structure of the cylinder and the screw is simple, the manufacturing cost is low and no mechanical trouble occurs. The waste material discharged from the extruder is air-cooled in the process of being crushed and then sent to the storage chamber, so that heat is not accumulated in the waste material and the resin does not deteriorate. In addition, since it is crushed into small pieces by a crusher, the volume is small, storage is easy, and it is easy to put it in a fuel oil conversion device later. The waste plastic foam volume-reduced by the volume reduction device of the present invention is
Not only is it easy to transport, but it is also suitable as a raw material for recycling systems such as fuel oil conversion.

[Brief description of drawings]

FIG. 1 is a side view of a volume reduction processing apparatus for a plastic foam waste material according to an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of an extruder of a volume reducing apparatus for a plastic foam waste material according to an embodiment of the present invention.

3 is a side view on the discharge side of the extruder shown in FIG. 1. FIG.

[Explanation of sign]

 DESCRIPTION OF SYMBOLS 1 Extruder 2 Crusher 3 Transport pipe 4 Blower 5 Transport pipe 6 Storage room 7 Cyclone 8 Cylinder 9 Screw 10 Screw 11 Motor 12 Input port 13 Gear wheel 14 Spiral fin 15 Volume reduction part 16 Volume reduction part

Claims (12)

[Claims] 1. A volume reduction process for a plastic foam, which comprises charging waste plastic foam material into an extruder to reduce the volume, discharging the extruder, crushing the crushed material, and then feeding the crushed material into a storage chamber. Law. 2. The volume reduction method according to claim 1, wherein the extruder is a twin-screw extruder. 3. The volume reduction method according to claim 1, wherein the plastic foam is a polyolefin foam. 4. An extruder for reducing the volume of the supplied plastic foam waste material, a crusher connected to the outlet side of the extruder, and a crushed product discharged from the outlet side of the crusher for pressure feeding to a storage chamber. 1. A volume reduction processing apparatus for waste plastic foam material, comprising: a transport pipe and a blower provided in the. 5. The extruder comprises a cylinder, two screws rotatably provided in the cylinder, and a motor for rotating the screw, and is formed in a taper shape whose cross-sectional area increases in the extrusion direction. The volume reducing apparatus for waste plastic foam material according to claim 4, wherein the reduced volume portion has a structure provided at a tip portion of the screw. 6. The volume reduction apparatus according to claim 4, wherein the plastic foam is a polyolefin foam. 7. The volume reduction apparatus according to claim 6, wherein the polyolefin foam is a crosslinked polyethylene foam. 8. The volume reducing apparatus according to claim 5, 6 or 7, wherein the distance between the fins provided on the surface of the two screws is 0 to 1.6 mm. 9. The volume reducing apparatus according to claim 4, wherein a space between the cylinder and the maximum diameter portion of the volume reducing portion of the screw is 1 to 5 mm. 10. The volume reducing apparatus according to claim 4, wherein a heating means is provided on the outer surface of the cylinder. 11. The volume reduction apparatus according to claim 10, wherein the heating means is an electric heater. 12. The volume reducing apparatus according to claim 4, wherein fins are provided on the surface of the volume reducing portion of the screw.