JPH101680A - Treatment of waste plastic before oil formation and installation therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pretreatment of waste plastics for enabling the waste plastic to be smoothly converted to oil in the oil recovery process by preparing light plastic of higher purity than that of the waste plastic in the pretreatment to suppress the trouble to the oil regenerator, facilitate handleability, prohibiting oil splash and increase the efficiency and capacity of the oil regenerator. SOLUTION: Waste plastic undergoes a magnetic separator 2, a crusher 3 and a dry type gravity separation machine 4 to collect fluffy light weight plastic. The fluffy plastic is further treated with a magnetic separator 5 and a non-ferrous separator 6 to obtain a plastic of higher purity, which is treated with an agglomerater 7 to prepare granules of the light-weight plastic with a size of about 5mm cube and a large bulk density whereby a raw material of lightweight plastic of easy handleability without splashing is produced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of removing foreign matter such as iron and non-ferrous metals from waste plastic garbage separated and collected from households and buildings with sufficient accuracy, and supplying the waste as a raw material to an oil processing apparatus. The present invention relates to a method and an apparatus for pre-oiling plastics.

[0002]

2. Description of the Related Art As one of measures to prevent the depletion of earth resources, especially fossil fuels such as petroleum, or the destruction of the natural environment by dumping waste plastics, waste plastics are used as resource waste. A technique of pretreating oil and converting the oil into oil by an oiling device has attracted attention. In the oiling device, various waste plastics can be liquefied to obtain fuel such as gasoline or kerosene.

[0003] When waste plastics are supplied as raw materials to such an oiling apparatus, pretreatment is generally performed since waste plastics used as various industrial products are not suitable for oiling treatment in their original form. In this conventional oiling pretreatment method, the collected waste plastics are first crushed by a crusher to about 15 mm or less, then the magnetic material is removed by a magnetic separator, and then water or water is separated by a wind separator or a wet specific gravity separator. Light plastics that are lighter than air and heavier, for example, iron, non-ferrous metals, glass, stone, sand, heavy plastics including high specific gravity plastics, etc., light plastics are packed into flexible containers etc. It is transported and supplied to the liquefaction unit.

[0004]

When the light plastic raw material pretreated by the above-mentioned conventional oil pretreatment method is supplied to the oiling apparatus to perform the oiling treatment, the supplied raw material is pretreated. Although foreign matter such as iron has been removed to some extent in the process, the foreign matter has not been completely removed. May cause. This is because removal of solid heavy foreign matter such as iron in the conventional pretreatment step is insufficient.

[0005] Further, when light or heavy plastics are sorted by a wind separator or a wet specific gravity separator in the above-described oil pretreatment method, for example, sorting by a wind separator is called a dry sorting method, and a gravity difference is utilized. It is a method that separates heavy and light plastics by sucking up light plastics by suction wind force and dropping heavy plastics and iron, etc., but dirt and smell attached to the waste plastics themselves. There are problems such as being unremovable and unsanitary.

As a method for eliminating such inconveniences,
It is possible to use a wet specific gravity sorter, but in this sorter, when crushed waste plastic is put into the water stored in the tank, light plastic with a low specific gravity rises,
Since heavy plastics with a high specific gravity are sorted out by sinking in water, waste plastics can be sorted out and dirt and odor can be eliminated.However, after sorting, light and heavy plastics are dehydrated and dried. There is a problem that a facility for treatment and a large-scale water treatment facility are required, and a large-scale facility requires a large number of installation locations, resulting in a large facility cost.

[0007] Further, the light plastics sorted by any of the above sorters is generally made of a light fluff (fluffy fuzzy) having a shape of about 15 mm or less,
It is easy to fly because its bulk specific gravity is extremely small, about 0.02,
There are also problems such as difficulty in carrying and handling such as packing work in a container, and difficulty in supplying to an oiling device.

The present invention is intended to remove various solid weight foreign matters and remove dirt and odor so as not to hinder the treatment in the subsequent oiling step, taking into account the various problems in the conventional pretreatment method described above. It is another object of the present invention to provide a waste plastic pretreatment method and apparatus capable of improving handling efficiency and performance in an oiling apparatus with good handleability during transportation on the way.

[0009]

According to the present invention, as a means for solving the above-mentioned problems, collected waste plastics containing foreign substances such as iron, non-ferrous metal, stone, sand, and high-density plastic are included in the refuse. Crushed plastic so as to have a fluffy size, fluffy light plastic is separated from the crushed waste by specific gravity, and then foreign substances such as iron and non-ferrous metals contained in the light plastic are removed by secondary sorting. Further, the fluff-like light plastic is shrunk to increase the bulk specific gravity to obtain a raw material agglomerated into flakes, thereby providing a pre-oiling pretreatment method for waste plastic.

[0010] The apparatus for performing the above method includes foreign substances such as iron, non-ferrous metal, stone, sand, and high specific gravity plastic.
A crusher that crushes the collected waste plastic garbage so that the plastic contained in the garbage becomes fluffy in size, a specific gravity separator that separates fluffy light plastic from the crushed garbage, and A secondary sorter that removes foreign substances such as ferrous and non-ferrous metals,
An agglomerator for shrinking the light plastic from which the ferrous and non-ferrous metals have been removed to increase the bulk specific gravity, secondary sorting of the light plastic by the secondary sorter, and flakes of the light plastic by the agglomerator It is also possible to use a waste plastic pretreatment device that is formed as a raw material.

In the pretreatment of waste plastics for oilification by the above method and apparatus, it is premised that waste plastics are first collected separately. Even in the case of the waste plastic garbage collected separately in this way, the plastic actually contains foreign matters such as iron, non-ferrous metal, stone, sand, and plastic having a high specific gravity.

[0012] Waste plastics include polyolefin-based plastics having a specific gravity smaller than that of water and other plastics which are heavier than water. The former is suitable for oily treatment, and the latter is unsuitable. Therefore, the method and apparatus of the present invention aim at extracting the former, which is as pure as possible and contains as little foreign matter as possible, by pretreatment. Therefore,
The above-mentioned plastic having a high specific gravity is heavier than water and is unsuitable for oiling.

[0013] Waste plastics containing foreign matter as described above are first crushed to a size smaller than a required size. In this case, the required size is such that the plastic contained in the waste plastic is crushed so as to have a fluff-like size of about 15 mm square or less. Therefore, if the primary crushing is insufficient, it is crushed by secondary crushing to one having a required size or less.

Next, the crushed waste plastic waste is sorted by specific gravity to separate it into light plastic and heavy plastic containing a large amount of foreign matter. Light plastics contain some foreign matter but have a specific gravity lighter than the specific gravity of water, while heavy plastics contain foreign matter and have a specific gravity heavier than water.

The means for selecting the specific gravity may be a dry-type wind separator or a wet-type separator. In a wind separator, a material having a low specific gravity is sucked up by suction air, and a material having a heavy specific gravity falls down even if suctioned by suction air, thereby performing sorting.

In a wet-type specific gravity separator, crushed waste plastic waste is put into water in a tank, and materials that are heavier than the specific gravity of the water sink, and those that are lighter are floated on the water surface, and are sorted.

When the oil is converted into oil by the oiling device as it is,
Foreign matter still remains in the plastics that can be used for oiling, which may cause failures, and because it is obtained in the form of fluff, it is difficult to carry out transportation and other operations and it is easy to scatter, so the entire supply is sufficiently oiled. It is not supplied to the device, and the processing efficiency is reduced.

For this reason, in the present invention, foreign substances contained in the light plastic are further removed by secondary sorting. As a means for the secondary sorting, a combination of a magnetic separator and a non-ferrous separator, or a wet specific gravity separator that separates foreign substances in a water layer formed in a hollow shape by centrifugal force can be used.

As described above, the light plastic from which foreign matter has been sufficiently removed by the secondary sorting is a high-purity plastic and is well suited to oiling. However, in the present invention, the subsequent processing operation is facilitated or oiling is performed. The light plastics are subjected to agglomeration processing so that the feed to the apparatus is reduced by scattering and does not lead to a decrease in the efficiency and capacity of the oiling apparatus.

This agglomeration device is generally called an agglomerator, and is a kind of granulation device. The light plastic to be charged is agitated by a blade and heated by frictional heat by stirring to convert the fluffy light plastic into a 5 mm square. Converts to less than flake-like grains. This simplifies the subsequent processing, and is sent to the next step in a container or the like.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic system diagram of an entire system for implementing the pre-oiling method of the present invention. 1 is a stock yard, 2 is a magnetic separator, 3 is a crusher, and 4 is a dry specific gravity separator. All of the above-mentioned constituent members are publicly known, and a detailed description thereof will be omitted. Although not shown, waste plastic garbage separated and collected from ordinary households and buildings is often wrapped in polyethylene garbage bags and the like. A machine may be provided to perform bag breaking processing.

The waste plastic waste introduced from the stock yard 1 is sent to a crusher 3 by removing a large magnetic metal such as iron by a strong magnet of a magnetic separator 2. In the illustrated example, a single-shaft crusher is used as the type of the crusher 3, but the crusher 3 is not limited to this, and another type such as a twin-shaft crusher may be used. This crusher 3 can crush waste plastic waste to a size of about 15 mm square or less in only one stage. The crusher may be of a two-stage system of coarse crushing and fine crushing, and may be capable of crushing dust to the above size by fine crushing.

Although not shown, the crushed waste plastic waste is sent to the next dry specific gravity sorter 4 by, for example, a pneumatic transportation device or a belt conveyor. The dry specific gravity sorter 4 can be a zigzag wind specific gravity sorter that sorts by suction air using, for example, a difference in specific gravity of refuse.
Heavy specific gravity can be sucked by the suction air within the zig-zag tube 4a falls also to the tank T _4, light light plastic specific gravity is stored are sorted in the storage hopper 4b.

It should be noted that a wet specific gravity sorter 4 'shown in FIG. 2 may be used instead of the dry specific gravity sorter 4, or a wet specific gravity sorter 4' is provided downstream of the dry specific gravity sorter 4. They may be used in combination. As shown in the drawing, when the wet specific gravity separator 4 'puts waste plastic pieces into the water in the separation tank T' as shown by the arrow, the lighter specific gravity floats on the water surface,
Those having a high specific gravity sink to the bottom of the water, and heavy foreign substances such as light plastic and heavy iron, non-ferrous metal, stone, sand, etc., which have been selected in this way, are carried out to the outside by belt conveyors 4a 'and 4b'. 4w is a water treatment device.

Even if foreign substances such as iron, non-ferrous metal, stone, sand, and heavy plastics are removed by the apparatus in each of the above-mentioned processing steps, the remaining light plastic still contains the same foreign substances as described above. In order to remove with high precision, an apparatus for the next processing step is further added. That is, the apparatus includes the magnetic separator 5, the non-ferrous separator 6, and the aggregator 7.

The magnetic separator 5 has two conveyors C ₅ and C ₅ ′.
Although a configuration in which a magnet 5a is provided between them is shown, a general magnetic separator 2 may be used instead of this type. The non-ferrous sorter 6 is a sorter that uses an attractive force and a repulsive force of ferrous and non-ferrous metals with respect to a rotating magnet, and non-ferrous metals such as aluminum are blown away and sorted.

The aggregator 7 is a kind of agglomeration device, and rotates a rotary blade 7a in a casing by a motor m to agitate light plastic pieces to generate heat.
By a kind of granulation action, a piece of light plastic is 5mm
Make it flake-like with less than square corners. The discharged light plastic flakes are sent to the conveyor 8 by the vibrating conveyor 7b. A large number of flexible containers 8a are placed on the conveyor 8 and each container 8a is packed with the light plastic flakes that have been subjected to the above-mentioned treatment, carried out to the outside, and carried to the next oiling device.

The light plastic from which foreign matter has been removed through the above steps is subjected to secondary sorting by the magnetic separator 5 and the non-ferrous sorter 6 so that the foreign matter contained therein is removed with the highest possible accuracy. From light plastic particles of extremely high purity.

Also, since the light plastic particles having a size of about 5 mm square or less are heated and granulated by the agglomerator 7, the dirt, oil and odor adhering to the light plastic pieces are removed by the action. Further, if the crushed material is crushed by the crushing machine 3 and only the specific gravity is selected by the dry-type specific gravity separator 4, the light plastic remains very fluffy and has a specific gravity of about 0.02, which is extremely light and easily scattered, so that subsequent handling is difficult. However, by performing the granulation treatment with an agglomerator, the specific gravity becomes about 0.2 or more, and the above-described difficulty is solved.

The combination of the magnetic separator 5 to the agglomerator 7 may be in the order of the components described above, but in this case, the entire amount of the fluffy light plastic raw material passes through the non-ferrous separator 6. Large raw material, non-ferrous sorting machine 6
Requires a large one with a large processing capacity.

For this reason, for example, as shown in the process path of FIG. 3, the magnetic separator 5 → agglomerator 7 → non-ferrous separator 6 may be installed in this order. In this case, granulation is carried out by the aggregator 7 while containing a small amount of non-ferrous metal.
If a method in which the light plastic granules having a small bulk after granulation are processed by the non-ferrous sorter 6 is adopted, the non-ferrous sorter 6 can be small, and the increase in installation cost can be suppressed.

The sorting of the light plastic pieces by the magnetic separator 5 and the non-ferrous metal separator 6 of the above embodiment may be replaced by the treatment by the wet specific gravity separator 10 shown in FIG. As shown in FIG. 5, the wet specific gravity sorting apparatus 10 is a new type different from the conventional one shown in FIG. 2 and has three functions of specific gravity sorting, washing and dehydration, and is a rotary type. Extremely high processing capacity.

As shown in the figure, light plastic is put into a water storage tank 11, and light plastic mixed in water from this tank is fed into a hollow shaft 12 a of a wet-type specific gravity separator 12 by a feed pump P. The wet specific gravity sorter 12 has a hollow shaft 1
2a is rotatably provided by a motor (not shown), and a number of blades 12b having different diameters are provided on the hollow shaft 12a in a slanted shape in opposite directions with respect to the center, and an opening is provided at the center and a partition plate is provided near the center. Is provided.

An outlet for circulating water is provided in the casing,
The water is returned to the water storage tank 11 by the circulation path 12c. Outlet of the light plastic 13a is that sorted, 13b iron, outlet of the foreign matter such as non-ferrous metals, T ₁₀ is a storage tank. Light plastic is sent to the water storage tank 11 by conveyor C _1, light plastic which is selected by a wet gravity separator 12 has another by conveyor C ₂ to send out the Aguromareta 7 the next step.

The wet-type specific gravity sorting apparatus 10 having the above structure can sort foreign substances contained in light plastic.
In the wet-type specific gravity separator 12, when the flow of light plastic mixed with water spouts from the center opening of the hollow shaft 12a, the blade is stirred by the blades 12b, the casing is rotated, and the water is deflected outward by centrifugal force and a hollow layer is formed in the center. it can.

Water rotating toward the outer side contains foreign matter having a higher specific gravity than water, such as iron and non-ferrous metals. Light plastic having a low specific gravity floats on the surface of the hollow layer, whereby the light plastic is separated and sorted. The light plastics are collected at the end of the hollow shaft by the blades having different inclinations, and light plastic is discharged from the discharge port 13a, and foreign matter having a high specific gravity is discharged from the discharge port 13b.

The above-mentioned wet specific gravity sorter may adopt a conventional type shown in FIG. 2 if importance is placed on its function.

In each of the above-described embodiments, both the first sorting means and the second sorting means can employ a combination of dry and wet sorting methods (four ways), but the second sorting means has a wet specific gravity. When a sorter is used, the first sorter is preferably a dry specific gravity sorter (wind sorter).

Conveyor means for transporting waste plastic or light plastic is required between each component, but illustration and description are omitted for simplicity, and the components are appropriately installed as necessary. It shall be.

Further, another crusher may be provided for further crushing the light plastic before the sorting by the second sorting means. In this way, it is possible to more reliably sort foreign matter with high accuracy.

[0041]

As described in detail above, in the method and apparatus for pre-oiling waste plastic according to the present invention, the collected waste plastic is crushed to a fluff-like size, and this is separated into primary specific gravity. The fluff-like light plastic is taken out, and the foreign matter contained in the light plastic is removed with high accuracy by secondary sorting, and the shrinkage is performed to increase the bulk specific gravity to obtain a flake-like agglomerate material. As a result, it is possible to supply flake-like agglomerated raw materials with sufficient precision to perform the oiling treatment with the oiling device, to remove dirt and smell by the agglomeration treatment, and to handle with an appropriate specific gravity. It is easy to supply because it is supplied as an agglomerate raw material, and there is an effect that a plastic raw material can be obtained which can contribute to the improvement of the processing efficiency and capacity of the oiling device.

[Brief description of the drawings]

FIG. 1 is an overall schematic system diagram of an oily pretreatment device according to an embodiment.

Fig. 2 Principle diagram of wet specific gravity separator

FIG. 3 is a diagram of another combination example of a magnetic separator, a non-ferrous separator, and an aggregator.

FIG. 4 is an overall configuration diagram of a wet specific gravity sorting device.

FIG. 5: Principle of the wet specific gravity separator

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stockyard 2 Magnetic separator 3 Crusher 4 Dry specific gravity separator 5 Magnetic separator 6 Non-ferrous separator 7 Agglomerator 8 Conveyor 10 Wet specific gravity separator 12 Wet specific gravity separator

Claims (6)

[Claims] 1. Collected waste plastic containing foreign matter such as iron, non-ferrous metal, stone, sand, and high specific gravity plastic is crushed so that the plastic contained in the garbage becomes fluffy in size, and the crushing is performed. The fluffy light plastic is separated from the garbage by specific gravity, and then the foreign substances such as iron and non-ferrous metal contained in the light plastic are removed by secondary sorting.
Furthermore, a pre-oiling treatment method for waste plastics, which comprises a process of shrinking the fluffy light plastic to increase the bulk specific gravity to obtain a raw material agglomerated into flakes. 2. A crusher for crushing collected waste plastic waste including foreign matters such as iron, non-ferrous metal, stone, sand, and high-density plastic so that the plastic contained in the waste has a fluff-like size. And a specific gravity separator for separating fluffy light plastics from the crushed waste, a secondary separator for removing foreign substances such as iron and non-ferrous metals contained in the light plastics, and removing the iron and non-ferrous metals. An agglomeration device for shrinking the light plastic to increase the bulk specific gravity, and for reducing the light plastic by the secondary sorter.
An oil pre-treatment device for waste plastics, which sorts the waste plastics and forms light plastics as flake-like raw materials using an agglomeration device. 3. The waste plastic pretreatment apparatus according to claim 2, wherein the specific gravity sorter is a dry type wind sorter. 4. The waste plastic pre-treating apparatus according to claim 2, wherein the specific gravity sorter is a wet specific gravity sorter. 5. The pretreatment device according to claim 3, wherein the secondary sorter is a magnetic sorter for removing iron and a nonferrous sorter for removing nonferrous metals. 6. The waste plasticizer according to claim 3, wherein the secondary sorter is a wet specific gravity sorter that sorts foreign substances in a water layer formed in a hollow shape by centrifugal force. Pretreatment device.