JPS59106931A - Treatment of waste plastic - Google Patents

Abstract

PURPOSE:To form waste plastic into an easily disposable configuration and to reduce the volume of a waste material, by classifying waste plastic from urban garbage after crushing to solidify the same into a rod shape by a screw type solidification apparatus. CONSTITUTION:Urban garbage is supplied to a crusher 2 from a feed hopper 1 while the crushed garbage is classified by an inertia classifier 5, a magnetic classifier 6 and an aluminum classifier 10 and classified stainless steel and plastic containers are sent to a plastic classifier 5. The classified plastic is divided into one with high bulk density and one with low bulk density by the plastic classifier 15 while a hard plastic material and a plastic film are crushed by a plastic crusher 19 and sent to a screw type plastic solidification apparatus 23 where melted and kneaded to be extruded from a nozzle as a columnar molded solid material. The waste plastic material solidified in a rod shape is discharged in a plastic receiving hopper 24 while cut to an appropriate length by a cutter.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for treating municipal waste, and particularly to a method for treating waste plastic materials in municipal waste.

There are two methods for treating waste plastic materials in municipal garbage: combustion treatment and solidification treatment. However, the former has drawbacks such as the generation of harmful gases such as hydrogen chloride gas when the plastic material is burned, and the fact that the hearth and walls of the combustion furnace are easily damaged by direct current. In addition, in the latter method, the separated plastic material contains a large number of impurities, making it difficult to solidify the plastic material. Not practical.

Another method is to dispose of municipal waste in a landfill, but plastic films and sheets tend to scatter,
Plastic containers must be covered with soil each time they are dumped, while plastic containers are bulky and have the disadvantage of shortening the lifespan of the landfill.

This invention was made in view of the above circumstances, and
Its main objective is to provide a processing method for compressing and solidifying waste plastic materials in municipal waste into small dimensions in a form convenient for disposal.

Another object of the present invention is to provide a treatment method that can treat plastic materials in municipal waste without combustion treatment.

Still another object of the present invention is to provide a processing method that enables compaction and solidification of waste plastic materials after separation from municipal waste even when the purity of the waste plastic materials is low.

In order to achieve the above-mentioned object, according to the invention, after the municipal waste has been shredded, the waste plastic material is separated, for example by inertial sorting. This separated waste plastic material is faced into a solidification device with a rotating screw inside a cylindrical casing, where the plastic components are melted and solidified into rods of convenient dimensions for disposal and discharged from the assimilation device. be done.

An embodiment of the present invention will be described below with reference to the drawings.

In Fig. 1, collected municipal waste is supplied from a supply hopper 1 to a crusher 2, and is crushed into pieces of, for example, 150 pieces or less. The crushed material is sent to an inertial sorter 5 by a vibrating conveyor 3 and a take-out conveyor 4. The inertial sorter 5 separates the crushed materials into heavy materials, such as gold and plastic containers for detergent, which cannot be crushed due to their elasticity, and paper, cloth, plastic, and current.

The separated heavy items are sent from the heavy waste outlet 5a to a magnetic separator 6, where they are sorted into iron scraps, non-ferrous entertainment scraps such as aluminum and stainless steel, and plastic container scraps.The iron scraps are sent from the input lower to the iron hopper 8. Sent. On the other hand, non-ferrous metal scraps and plastic container scraps are sent to an aluminum sorter 10 through a conveyor 9, and aluminum scraps are sent to an aluminum hopper 12 through a passage 11. On the other hand, the stainless steel and plastic containers sorted by the aluminum sorter 10 are sent through a conveyor 14 to a plastic sorter 15 that uses inertial sorting.

On the other hand, light materials such as paper, cloth, crushed plastic materials, and cullet are sorted by the inertial sorter 5.
The light objects are discharged from the light object outlet 5b to the conveyor 16, and the light objects are sent to the rotary sorter 17 by the conveyor 16. The rotary sorter 16 separates the above-mentioned lightweight items at a rate of 50rI.
Sorting into large and small items based on the n angle, and discharging small items of 50rrvn angle or less from the outlet 17a to the conveyor 14,
Large items larger than 50+++m square are 11 l 7 b
The waste is then sent to a hopper 18 for landfill.

Light items sent by conveyor 14 go to plastic sorter 1
At step 5, lightweight materials having a bulk specific gravity of 0.05 to 0.03, that is, hard plastic materials and plastic films, are separated into those with a large bulk specific gravity and those with a small bulk specific gravity, and are sent from an outlet 15a to a plastic crusher 19. Cloth, corrugated paper, stainless steel, brass, and plastic containers having a large bulk specific gravity are supplied to the combustible material hopper 20 from the outlet 15b.

plastic material crushed by a plastic crusher 19;
Plastic films, etc. are passed through a conveyor 21 and a quantitative feeder 22 to a plastic solidifying device 2 with a set of screws.
Sent to 3.

As shown in FIG. 2, the plastic assimilation device has a casing portion formed by integrally connecting a large-diameter cylindrical casing 31 and a small-diameter cylindrical nozzle 32 with a cone portion 33. The screw shaft 34 and the gas contact 35 in the nozzle 32 are integrally connected by a tapered part 36 in the cone part 33 to form a part of the screw.

Tapered portion 36 from screw shaft 34 of the screw portion
A series of screw blades 37 are formed on the outer periphery of the gas contact 35 up to its root portion.

The rear part of the screw shaft 34 is rotatably supported by a bearing 38, and is connected to sprockets 39a, 39b and the chain 4.
0 to the geared motor 41, and the motor 4
With one rotation, the waste plastic immersed from the input port 42 provided at the rear of the casing 31 is transferred to the screw blade 37.
While sending it forward with
, a tapered portion 36), and extruded from the nozzle 32 as a cylindrical solidified product.

46 is a heater. 47 is a heater control device.

Regarding structure A of the tip molding part of the plastic solidification device,
As shown in Figure 3, the nozzle length □ is set at least three times the length corresponding to the nozzle diameter, and the gas contact
The length of 5 is set to be shorter than the nozzle tip by a length l corresponding to the nozzle diameter.

The waste plastic material solidified into a rod shape as described above is cut into appropriate lengths by a cutting machine and transported to the plastic hopper 2.
Released at 4.

In addition, in FIG. 1, the outlet 17 of the rotary sorter 17
The cullet etc. discharged from b may be supplied to the solidification device 23 and solidified in a formation together with the plastic material.

As detailed above, this invention crushes municipal waste, sorts waste plastic materials, and solidifies the waste plastic materials with a small bulk specific gravity into a rod shape using an assimilation device with a set of screws, so that it can be easily disposed of. At the same time,
The volume of waste can be reduced.

Furthermore, since a set of screws is used as the assimilation device, it is possible to solidify even low-purity plastic materials, and a combustion device for waste plastic materials is not required.
It also eliminates the generation of harmful gases such as hydrogen chloride gas, and is effective in preventing pollution.

[Brief explanation of drawings]

Fig. 1 is a diagram showing an embodiment of the present invention, Fig. 2 is a sectional view showing an example of the plastic assimilation device used in the embodiment of Fig. 1, and Fig. 3 is a sectional view of the main part of the device shown in Fig. 2. It is a diagram. 2... Crusher, 5... Inertial sorter, 15... Plastic sorter, 23... Plastic assimilation device. Patent applicant Fuji Electric Manufacturing Co., Ltd.

Claims (1)

[Claims] After crushing municipal waste with a crushing device, the plastic material is separated from other crushed materials, and a motor-driven screw is installed in a cylindrical casing, and the separated plastic material is crushed by the rotational force of the screw. A method for processing waste plastics, which comprises supplying the plastic material to a screw set assimilation device that melts and solidifies the plastic material, and obtains a rod-shaped plastic material from the screw set solidification device.