JPH0671647A - Method for recycling waste - Google Patents

Abstract

PURPOSE:To recycle waste without causing secondary pollution by mixing fibrous waste, plastic waste, and inorganic waste and compression-molding the mixture at temperatures at least the melting point of the thermoplastic resin waste and at most the thermal degradation temperature of the fibrous waste contained in the waste mixture. CONSTITUTION:Fibrous waste including paper, textiles, and wood is preferably cut into appropriate sizes. Paper pieces cut by a shredder can also be used. Inorganic waste including earth and sand, rubble, glass, and ashes is crushed previously. Plastic waste must include thermoplastics. The waste of each type is weighed separately and then mixed together. The mixture is heated at temperatures of at least the melting point of the thermoplastic resin waste and at most the thermal degradation temperature of the fibrous waste for compression molding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to waste recycling, and more particularly to a method for recycling fibrous waste and plastic waste.

[0002]

2. Description of the Related Art Plastic waste, which accounts for a large proportion of industrial waste and municipal waste, is difficult to incinerate due to problems such as by-products of harmful substances and damage to incinerators, and recovery and reuse. Is desired. Therefore, as a conventional method for recycling plastic waste, fuel production (Japanese Patent Laid-Open Nos. 59-56496, 1-182012, and 49-49)
121876, Japanese Unexamined Patent Publication No. 50-109271), a recycling method as a forming raw material (Japanese Unexamined Patent Publication No. 54-22746, Japanese Unexamined Patent Publication No. 47-33965), a manufacturing method of tiles, blocks, etc. −1018
68, JP-A-47-17876, etc.) have been developed.

The fibrous waste includes fiber rags such as used clothes, waste paper, and wood waste. Recycling of fiber rags and used paper has been promoted so far, and used paper is used as a raw material for papermaking, and fiber rag is used as a recycled fiber raw material and a waste cloth for oil wiping.

[0004]

In recent years, companies and the like are often using a shredder to finely cut and dispose of documents for the purpose of maintaining confidentiality. Shredder finely chopped paper fibers are too short and are no longer suitable as raw materials for papermaking.

In recent years, the proportion of chemical fiber products has become extremely high, and the reuse of fiber rags is becoming less common than in the past.

A large proportion of vinyl chloride is contained in plastic waste, and when incinerated, harmful chlorine compounds such as hydrogen chloride gas are generated, which can be a source of secondary pollution.

The object of the present invention is to make it possible to treat wastes that were difficult to treat by these conventional techniques without causing secondary pollution, and to recycle the wastes to generate the amount thereof. To provide a method of reducing

[0008]

A method for recycling waste according to the present invention is a method for recycling fibrous waste mainly composed of paper, cloth, etc.
Or, after blending the inorganic waste and the plastic waste, use a molding device that is heated to a temperature above the melting temperature of the thermoplastic in the plastic waste and below the heat deterioration temperature of the fibrous waste. It is characterized by obtaining a molded product of.

In addition, when the plastic waste is mixed with the fibrous waste and / or the inorganic waste, the plastic waste is preheated to melt the contained thermoplastic, and then the fibrous waste and / or Characterized by mixing inorganic waste.

Further, it is characterized in that the inorganic waste is an inorganic waste such as glass, earth and sand, and gravel pieces, and these are in a pulverized and finely divided powder form.

Further, the fibrous waste is characterized by being paper-based waste in which fibers are shredded by a shredder or the like and / or shredded wood-derived waste.

[0012]

The features of the method for recycling waste according to the present invention are as follows:
The purpose is to mix fibrous wastes, inorganic wastes, and plastic wastes, heat them above the melting temperature of thermoplastics, and obtain a desired molded product using a molding device.

Examples of the fibrous waste suitable for the present invention include textile products waste used for paper, clothes and the like, waste wood and the like. It is desirable that these wastes are cut into an appropriate size by a crusher, a cutting machine, or the like. In addition, it is desirable that these be dried in advance. It should be noted that synthetic fibers such as nylon fibers and polyester fibers may be mixed, but they are included in the category of plastic waste when calculating the mixed composition of each waste.

As the inorganic waste, earth and sand, gravel pieces, glass pieces and combustion ash such as coal can be used. It is necessary that these wastes be in the form of powder that has been previously crushed by a crusher or the like. Further, it is desirable that it be dried in advance.

It is essential that the plastic waste contains a thermoplastic, but there is no problem even if a thermosetting plastic or a composite material such as a plastic-metal or a plastic-inorganic substance is mixed. However, it is desirable that the proportion of thermoplastic is at least 20% or more. Further, it is desirable that these plastic wastes are previously crushed by a crusher or the like.

The fibrous waste, the inorganic waste and the plastic waste are respectively weighed and mixed. The blending ratio in that case is particularly important for the ratio of the thermoplastic, and the weight ratio is at least 20% or more, preferably 40%.
The above is desirable. Further, since the fibrous waste greatly affects the mechanical strength of the recycled product, it is effective to increase the proportion of the fibrous waste in the production of a molded product that requires toughness. The mixed waste mixture is molded into a desired shape by a known plastic molding method. That is, the powdery waste mixture is directly put in a molding die and heated to a temperature not lower than the melting start temperature of the thermoplastic to perform pressure molding, or the powdery waste mixture is preliminarily mixed with the thermoplastic After kneading and melting with a mixing roll heated to a temperature above the melting start temperature, placing in a molding die for pressure molding, and after supplying the waste mixture in powder form to a heated screw feeder and kneading and melting. Molding is performed by using a method such as injection molding.

When blending the fibrous waste, the inorganic waste and the plastic waste, the plastic waste is preheated to melt the contained thermoplastic and then the fibrous waste and the inorganic waste are mixed. You can also do it. This is particularly effective when the plastic waste contains a large amount of foam.

[0018]

EXAMPLES Examples will be described below.

<Example 1> Styrofoam cool box 1.
5 kg was crushed by a crusher and crushed to about 5 to 15 mm square. Then, the Styrofoam powder was melted using a kneading roll heated to a temperature of 140 to 150 degrees. Then, 0.5 kg of shredded paper waste was added little by little to knead. The kneaded product was almost black, and phthalocyanine blue, which is a coloring pigment, was added for coloring. After that, the mixture was taken out from the kneading roll to obtain a sheet-like mixture having a thickness of 2 to 4 mm. Next, after taking a part of the mixture sheet and crushing it into about 10 mm square, a diameter of 10 cm and a height of 13
It was put in a pressure molding die for a flower pot of cm and pressure-molded at 140 degrees. The obtained flower pot was sufficiently practical.

<Example 2> Styrofoam such as heat insulation case and packaging tray, plastic buckets, plastic waste such as vinyl bags were collected and crushed to a size of 2 to 5 mm by using a crusher and a cutter. Next, prepare paper scraps cut into about 2 × 5 mm by a shredder, glass shredded to 1 mm or less, and wood scraps shredded to 1 mm or less.
It was dried at a temperature of about a degree. Next, plastic waste 50
Parts by weight, paper waste 20 parts by weight, glass scrap 10 parts by weight, wood scrap 10
Parts by weight were taken and mixed. Then, the mixture is fed to a screw feeder heated to a temperature of about 160 ° C. to melt the thermoplastic resin, and paper waste, glass waste,
After sufficiently kneading with the wood chips, the kneaded product was extruded into an injection molding die that was in close contact with the screw feeder outlet to obtain a flowerpot molded product.

[0021]

According to the present invention, it is possible to effectively utilize the shredder cut paper waste that has been conventionally incinerated.
Moreover, a recycled plastic molded product having high mechanical strength can be obtained, and the amount of paper waste and plastic waste can be reduced. Also, since a large amount of cellulose, which is easily decomposed in the natural world, is contained in the plastic molded product, when it is buried in the soil, the cellulose is quickly decomposed and weakened, the shape of the molded product is easily collapsed, and its volume is greatly reduced. Can be reduced to

Claims (5)

[Claims] 1. After blending fibrous waste such as paper, cloth, etc., plastic waste, inorganic waste such as glass, gravel fragments, etc., the melting point of the thermoplastic resin in the plastic waste or higher, and the fibrous property. A method for recycling waste, comprising obtaining a desired molded product by using a pressure molding device heated to a temperature not higher than a heat deterioration temperature of the waste. 2. The method according to claim 1, wherein the plastic waste is preheated to melt the contained thermoplastic resin, and then the fibrous waste and / or the inorganic waste is mixed. Resource recycling method. 3. The recycling of waste according to claim 1 or 2, wherein the inorganic waste is an inorganic waste such as glass, earth and sand, and gravel pieces, and these are pulverized and finely divided into powder form. Method. 4. The method for recycling waste according to claim 1, 2 or 3, wherein the fibrous waste is paper in which fibers are shredded by a shredder or the like. 5. The method for recycling waste according to claim 1, 2 or 3, wherein the fibrous waste is fragmented wood-derived waste.