JPH06134439A - Apparatus for continuous hydrolysis of waste synthetic resin with coated film - Google Patents

Abstract

PURPOSE:To provide an apparatus for continuous hydrolysis of waste synthetic resin with a coated film without causing deterioration of its strength. CONSTITUTION:A rotary shaft 13d equipped with a screw blade 13e is installed in a cylindrical casing 13c having an inlet 13f for crushed material, an outlet 13g for crushed material, an opening 13h for supplying steam, and an opening 13i for discharging steam. The hollow rotary shaft makes a steam passage. Steam ejected from a steam-blowout opening 13p installed on the periphery of the rotary shaft flows down along the stream of the material through a steam hole 13q. In this way, the film on the surface of the waste material can be hydrolyzed continuously in a short time into a low molecular weight product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for hydrolyzing a coated synthetic resin waste material, and more particularly to an apparatus for hydrolyzing pulverized materials continuously.

[0002]

2. Description of the Related Art In recent years, it has been required to recycle synthetic resin waste materials from the viewpoint of environmental protection, but it is usual to melt and remold the waste materials. However, in Japan, it is common to apply a thermosetting paint to the surface of the synthetic resin material in order to maintain the beauty of the product.
Even if the waste material is melted, the paint is not decomposed, and if it is remolded as it is, it is inevitable that the material strength is deteriorated because the coating film is mixed.

For example, when a bumper is made of waste material,
Collision resistance in cold regions is lower than that of new materials. If the coating film is removed, the reduction in material strength can be avoided, but it is difficult to remove the coating film. That is, it is possible to mechanically remove the coating film by shot blasting etc., but if the shape of the parts is complicated, not only it takes time to remove the coating film, but also it cannot be completely removed. Not suitable for processing.

It has also been proposed to strip the coating with organic salts, but the use of organic salts cannot overcome the environmental problems. In order to solve the above problems, the present applicant has proposed a method in which a synthetic resin waste material with a coating film is melt-kneaded and reused after the hydrolysis treatment without removing the coating film (Japanese Patent Application No. 3-103). 192431).

[0005]

However, in order to shorten the treatment time, it is necessary to carry out hydrolysis in a relatively high temperature atmosphere of 180 ° C. for a short time, but avoid melting of the synthetic resin. It is not possible. Therefore, when the synthetic resin is taken out from the reaction vessel after completion of hydrolysis and once cooled, the synthetic resin is solidified and must be crushed when it is reused, which makes continuous treatment difficult.

When the post-process is carried out in the molten state, it is necessary to keep the synthetic resin passage in a predetermined atmosphere, which is against the social demand for energy saving. The present invention has been made in view of the above problems, and an object thereof is to provide a continuous hydrolysis device capable of continuously hydrolyzing a crushed material of a coated resin waste material without deteriorating the material strength. And

[0007]

A continuous hydrolysis apparatus for coated synthetic resin waste material according to the present invention has a pulverized material supply port, a pulverized material discharge port, and a steam supply port and at least one discharge port. , Cylindrical hydrolysis tank casing that hydrolyzes the crushed paint film of synthetic resin waste material, and transports the crushed material supplied from the crushed material supply port in the hydrolysis tank casing to the crushed material discharge port And a screw vane that forms a steam flow passage that guides steam in the axial direction of the hydrolysis tank casing, and the rotary shaft of the screw vane is a hollow steam that is formed on the rotary shaft and is guided to the hollow flow passage. Is provided with a plurality of steam holes for ejecting water vapor into the hydrolysis tank casing, and a plurality of steam holes formed on the screw blades for allowing the steam ejected into the hydrolysis tank to pass in the axial direction of the rotation axis of the screw blades.

[0008]

According to the continuous hydrolysis apparatus for waste synthetic resin material with a coating film according to the present invention, a flow from upstream to downstream in the hydrolysis tank casing of steam ejected from the steam ejection port is formed and crushed. The hydrolysis of the coating film on the coated synthetic resin waste material is accelerated.

[0009]

EXAMPLE FIG. 1 is a flow sheet of a continuous recycling apparatus for synthetic resin waste material with a coating film. The coated resin waste material is, for example, a polypropylene (hereinafter referred to as PP) bumper 100, the surface of which is coated with polyester / melamine or acrylic / melamine paint.

If the synthetic resin is a thermoplastic resin, P
It is not limited to P and may be modified polypropylene, polyethylene, ABS resin, AS resin, polyamide resin, polyester resin, polycarbonate resin, polyacetal resin, polyphenylene oxide or modified polyphenylene oxide. The coating material applied may be urethane-based or amino-resin-based coating that is hydrolyzed to have a low molecular weight.

The crushing device 110 is composed of a coarse crusher 111 and a fine crusher 112, and the bumper 1 coated
00 is crushed into pieces of a predetermined length by the coarse crusher 111, and then crushed by the fine crusher 112 to be a crushed material of about 5 mm square or less. This pulverized material is supplied to the first metering and sending device 120, and the suction fan 1
2a, transport pipe 12b, cyclone 12c, rotary feeder 12d, stock bin 12e, feed screw 12f
And 12 g of the constant-volume feeding screw.

That is, the pulverized material is sucked by the suction fan 12a and is fed from the transportation pipe 12b to the cyclone 12c. The crushed material stored in the cyclone 12c is the rotary feeder 12d installed at the bottom of the cyclone 12c.
Is discharged to the crushed material stock bin 12e. The crushed material discharged to the crushed material stock bin 12e is the feed screw 12 installed at the bottom of the crushed material stock bin 12e.
It is transported to one side by f, and is fed to the hydrolysis device 130 by a fixed amount by the constant-volume feed screw 12g.

FIG. 2 is a cross-sectional view of the hydrolysis device 130. The supply side seal rotary feeder 131, the hydrolysis tank 132 and the discharge side seal rotary feeder 1 are shown.
It consists of 33. Supply-side seal rotary feeder 131 and discharge-side seal rotary feeder 13
3 has the same structure and has a cylindrical casing 13a.
And a rotor 13b.

In the rotary feeder, the casing 13
The pulverized material supplied from the material supply port provided in the upper part of a is a rotor 13 driven by a motor (not shown).
It is quantitatively conveyed to the crushed material discharge port provided in the lower portion of the casing 13a by the concave portion provided in b. That is, by adjusting the rotation speed of the rotor, the amount of the pulverized material supplied to or discharged from the hydrolysis tank can be adjusted.

The rotor 13b is assembled so as to be in contact with the casing 13a, and the high temperature and high pressure atmosphere in the hydrolysis tank 132 is the first metering and feeding device 12 on the supply side.
0 and the discharge side drying device 140 are prevented from leaking. The hydrolysis tank 132 is a device for hydrolyzing the pulverized material, and a hollow rotating shaft 13d is installed along the axis of the cylindrical casing 13c. Rotating shaft 13d
Is provided with screw blades 13e around it, and when the rotating shaft 13d is rotated by a motor (not shown), the pulverized material supplied from the material supply port 13f is discharged to the material discharge port 13g.
Be transported to.

Further, a steam outlet is opened around the rotary shaft 13d, and the steam supplied from the steam supply port 13h through the steam flow passage in the rotary shaft 13d is jetted out. While the supplied pulverized material is transported to the material discharge port 13g, the coating film on the surface of the pulverized material is hydrolyzed and reduced in molecular weight. Further, after the treatment, the hydrolyzed and low-molecular weight coating film is attached to the periphery of the pulverized material.

The temperature and pressure conditions in the hydrolysis tank 132 are not particularly limited, but in order to shorten the time required for hydrolysis and to facilitate the handling of the crushed material after hydrolysis, the range in which the crushed material does not melt Therefore, it is desirable to raise the temperature as high as possible. This is because the crushed material cannot be transported by the screw blade 13e when the crushed material is melted.

The pressure in the hydrolysis tank 132 is controlled by a relief valve 13j connected to the steam outlet 13i. Further, steam chambers 13k are provided at both ends of the hydrolysis tank 132, and are connected to each other by a steam flow path in the rotating shaft 13d. That is, the pressures of the two steam chambers are always maintained equal to each other to prevent the axial thrust in one direction from being generated by the steam, which makes it possible to simplify the thrust bearing.

The crushed material transported to the jetted material discharge port 13g is discharged by the recess of the rotor 13b of the seal rotary feeder 133 on the discharge side and supplied to the drying device 140. The drying device 140 includes a drying furnace 141, a rotary feeder 142, a bag filter 143, and a suction fan 144.

A hot air generating furnace (not shown) is used in the drying furnace 141.
Moisture contained in the pulverized material by several percent (wt.%) Is removed to 0.2% or less by the hot air generated in. The air containing water is sucked by the suction fan 144 and released into the air.
The paint and PP pulverized by the bag filter 143 may be removed before being released into the atmosphere.

The pulverized material in which the coating film accumulated at the bottom of the drying furnace 141 is hydrolyzed is discharged by the rotary feeder 142 and supplied to the second weighing and feeding device 150. The second weighing-out device 150 is similar to the first weighing-out device 120 in that the suction fan 15a and the transport pipe 15
b, a cyclone 15c, a rotary feeder 15d, a stock bin 15e, a feed screw 15f, and a fixed amount feed screw 15g, and a pulverized material whose coating film is hydrolyzed is supplied to the melt-kneading device 160.

The melt-kneading device 160 comprises a biaxial kneader 161 and an extrusion die 162. In the twin-screw kneader 161, the hydrolyzed pulverized material is melt-kneaded in order to atomize the hydrolyzed coating film to, for example, several tens of micrometers or less and knead it into the resin. The melt-kneaded material is extruded from an extruding die 162 having a diameter of, for example, 4 mm to be a linear material, and is supplied to the pellet material manufacturing apparatus 170.

The pellet material manufacturing apparatus 170 is equipped with a cooling water tank 1.
71 and a cutting machine 172. Extrusion die 1
The linear material extruded from 62 is cooled and hardened in the cooling water tank 171. Then, it is cut by a cutting machine 172 into a predetermined length of, for example, 2 millimeters to form a cylindrical pellet material. This pellet material is used as a raw material in a bumper manufacturing process (not shown), for example.

FIG. 3 is a partial cross-sectional view of the hydrolysis tank 132 according to the first embodiment, in which the steam jet port 13p opens to the rotary shaft 13d of the screw blade 13e. The steam holes 13q are opened at the base of the screw blade 13e. Therefore, in the hydrolysis chamber R, a steam flow (arrow A in FIG. 3) passing through the steam holes 13q and traveling from the upstream hydrolysis chamber R to the downstream hydrolysis chamber is generated.

This vapor flow makes it possible to accelerate the hydrolysis of the coating film on the surface of the pulverized material. Furthermore, since this steam flow flows over the steam outlet 13p opening to the rotating shaft 13d of the screw blade 13e, the steam outlet 13p
It is prevented that the finely pulverized pulverized material is accumulated on the p and the flow of steam is stagnated.

FIG. 4 is a partial cross-sectional view of the hydrolysis tank 132 according to the second embodiment, in which the steam holes 13q are opened in the entire screw blade 13e. Therefore, a stronger vapor flow is generated from the upstream hydrolysis chamber to the downstream hydrolysis chamber, and it becomes possible to further accelerate the hydrolysis rate.

[0027]

According to the present invention, it is possible to accelerate the hydrolysis rate of the coating film on the surface of the pulverized material by the vapor flow from the upstream hydrolysis chamber to the downstream hydrolysis chamber.

[Brief description of drawings]

FIG. 1 is a flow sheet of a continuous recycling apparatus for coated synthetic resin waste materials.

FIG. 2 is a sectional view of a hydrolysis device.

FIG. 3 is a partial cross-sectional view of the first embodiment.

FIG. 4 is a partial cross-sectional view of the second embodiment.

[Explanation of symbols]

 13c ... Casing 13d ... Rotating shaft 13e ... Screw blade 13f ... Grinding material supply port 13g ... Grinding material discharge port 13h ... Steam supply port 13i ... Steam discharge port 13j ... Relief valve 13p ... Steam ejection hole 13q ... Steam hole

Claims (1)

[Claims] 1. A cylindrical hydrant having a pulverized material supply port, a pulverized material discharge port, and a steam supply port and at least one discharge port for hydrolyzing a pulverized coated film of a synthetic resin waste material with a coated film. A decomposition tank casing, and a screw blade that transports the pulverized material supplied from the pulverized material supply port to the pulverized material discharge port in the hydrolysis tank casing, and the rotating shaft of the screw blade is a hydrolysis tank casing. Is a hollow that constitutes a steam flow path that leads in the axial direction of, and is formed in a rotating shaft, and is formed in a screw blade and a steam jet port that spouts the steam that is guided into the hollow flow path into the hydrolysis tank casing. A continuous hydrolysis device for a coated synthetic resin waste material, which is provided with a plurality of steam holes that allow steam ejected into the hydrolysis tank casing to pass in the axial direction of the rotation axis of the screw blades.