Method for crushing and cleaning waste material and device for crushing and cleaning waste material

Abstract

To provide a device that has a function of breaking up a clump of crushed pieces in addition to transporting waste plastic, efficiently dehydrating dispersed crushed pieces, and regenerating a resulting material into a high-purity plastic raw material.SOLUTION: There is provided a device for crushing and cleaning a waste material, comprising: a cleaning and crushing machine; a washer / dehydrator 2 that crushes a waste material into a predetermined shape and size, and washes a crushed waste by spraying water while rotating the crushed waste, removing dirt from the crushed waste, and removing moisture from a surface thereof; a gravity separator 8 that separates a pulverized material into floating film-like pulverized material and pulverized material such as plastics and metals that sink to a bottom of water in a separation tank 81 based on a difference in specific gravity; a screw conveyor; and a dehydrator 4 that rotates and centrifugally dehydrates the film-like pulverized material while twisting the material.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a technology for recycling discarded plastics, and more particularly to a method and apparatus for crushing and cleaning waste, which crushes waste such as plastic bags and plastic wrap used to wrap food, washes the crushed film, and dehydrates the water therefrom. [Background technology]

[0002] Technologies have been developed to separate, crush, and clean non-burnable waste such as plastic bags and plastic wrap used to wrap food, and the waste is being reused as plastic raw materials. The recycling method used is shown in the process diagrams in Figures 14(a) and (b). First, in the crushing process, non-burnable waste such as plastic bags and plastic wrap is crushed to a specified size using a crushing device. This crushed film is then washed in water or chemicals in the water washing process. Next, in the gravity separation process, the crushed film floats on water, while any mixed-in PET (polyethylene terephthalate) or metals such as caps are allowed to settle and are separated by type. As shown in Figure 14(b), this film-like pulverized material containing a lot of water is subjected to a centrifugal dehydration process to remove the moisture. This film-like pulverized material containing water is then dried in a hot air drying process. Film-like plastic raw materials that have undergone these processing steps can be used for a wide range of purposes.

[0003] Therefore, techniques for washing waste plastics when recycling them have been proposed. For example, Patent Document 1, JP 2008-80679 A, ​​"Waste Plastic Washing Device," proposes a waste plastic washing device in which a stirring blade is provided inside a cylindrical screen so as to be rotatable around the cylindrical axis of the screen, and by rotating the stirring blade, foreign matter adhering to waste plastics fed into the screen is separated and discharged outside the screen, in which the gap between the inner peripheral surface of the screen and the tip of the stirring blade changes in size in the direction of rotation of the stirring blade. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-80679 A Summary of the Invention [Problem to be solved by the invention]

[0005] In this conventional regeneration method, the moisture adhering to the surface of the film-like pulverized material can be removed by the centrifugal force of the dehydrator used in the centrifugal dehydration process, but the moisture enclosed within the film could not be removed even after a long time in this centrifugal dehydrator. In particular, since the centrifugal dehydrator is designed to have rotating blades inside a cylindrical mesh plate and to remove the moisture adhering to the film-like pulverized material by the rotational force of these rotating blades, there was a problem in that once the film-like pulverized material stuck to the cylindrical mesh plate, the dehydration function rapidly decreased.

[0006] Furthermore, in the separation tank used in the conventional gravity separation process, clumps of plastics and metals that should be allowed to settle get caught between the numerous film-like crushed materials and are transported to the next process as is, which creates the problem of easily clogging the mesh plates of the dehydration device.

[0007] Furthermore, if lumps of crushed waste material are formed during processing, there is a problem in that the difference in specific gravity makes it impossible to accurately separate the material into floating and sinking particles in the water tank of the next specific gravity separation process.

[0008] The present invention has been devised to solve these problems. That is, the object of the present invention is to provide a method and apparatus for crushing and washing waste plastics, which not only has the function of transporting the waste plastics but also the function of breaking up clumps of crushed pieces, and which can efficiently dehydrate the dispersed crushed pieces and recycle them into high-purity plastic raw materials. [Means for solving the problem]

[0009] The method for crushing and cleaning waste of the present invention includes a crushing step (S1) of crushing plastic waste into a predetermined shape and size; a water washing step (S2) for removing dirt from the pulverized waste material; a washing and dehydration step (S3) in which a screw blade (24) spirally wound around a rotary shaft (23) in a dehydration tank (22) having a semi-cylindrical screen (25) with a large number of holes drilled in the housing, and square plate-like beating plates (28) attached to two positions of the screw blade (24) so ​​as to span one pitch (P) of the screw blade (24) in the longitudinal direction of the rotary shaft (23) break up lumps of the pulverized material being conveyed, disperse moisture, remove dirt from the pulverized material, and remove surface moisture; a gravity separation step (S5) in which the pulverized material is separated into floating pulverized material and pulverized material such as plastics and metals that sink to the bottom of the water in a separation water tank (81) based on the difference in specific gravity; The method further comprises a dehydration step (S22, S31) in which the pulverized material is twisted and centrifuged to remove moisture adhering to the pulverized material while intermittently injecting air onto the pulverized material. After the washing and dehydration step (S3), a rinsing step (S4) can be added in which the pulverized material is placed into a substantially cylindrical screw conveyor (3), the water adhering to the surface of the pulverized material is allowed to drip, and the water is squeezed out and removed.

[0010] The waste crushing and washing treatment device of the present invention comprises a washer / crusher (1) that crushes waste into a predetermined shape and size and washes the crushed waste by spraying water while rotating the crushed waste; a screw conveyor-type washer / dehydrator (2) comprising: a dehydration tank (22) having a semi-cylindrical screen (25) with a number of holes in the casing for removing dirt from the crushed waste material and removing moisture from the surface; a screw blade (24) spirally wound around a rotary shaft (23) that rotates within the dehydration tank (22); and one or more square beating plates (28) attached to two positions on the screw blade (24) so ​​as to span the rotary shaft (23) in the longitudinal direction over one pitch (P) of the screw blade (24); a gravity separator (8) for separating the pulverized waste material into floating film-like pulverized material and pulverized material such as plastics and metals that sink to the bottom of the water in a separation tank (81) based on the difference in specific gravity; a screw conveyor (3) having a rotatable screw shaft in a substantially cylindrical feeder body (31), a cylindrical mesh plate for dripping water in about half of the feeder body (31) on the inlet (32) side, and a screen with slits formed in its longitudinal direction in about half of the feeder body (31) on the outlet (33) side; The apparatus is characterized by including a dehydrator (4) that rotates and centrifugally dehydrates the pulverized material conveyed by the screw conveyor (3) to remove moisture adhering to the pulverized material.

[0011] It is preferable that a plurality of the beating plates (28) are attached to the screw blade (24) of the washer / extractor (2). The beating plates (28) of the washer / extractor (2) are attached to two locations of the screw blades (24) within one pitch (P) of the screw blades (24) so ​​as not to come into contact with the rotating shaft (23).

[0012] The gravity separator (8) A rotating blade is provided at the opening of the separation tank (81) that rotates on the water surface from the inlet (82) to the outlet (83), and a screw shaft is provided to discharge the crushed material that settles to the bottom of the separation tank (81). [Effects of the Invention]

[0013] In the configuration of the above invention, non-burnable waste such as plastic bags and plastic wrap, which has been sorted and processed to remove other different materials, is crushed to a predetermined shape and size in a crushing process (S1) (cleaning crusher (1)), and this crushed waste is washed by water spraying or the like in a water washing process (S2) (cleaning crusher (1)). This crushed waste is then transported in a washing and dehydrating process (S3) (cleaning and dehydrating machine (2)), where clumps of crushed material are broken down and the water is scattered to remove dirt from the crushed material and remove moisture from the surface. Next, in a specific gravity separation process (specific gravity separator (8)), the waste is separated into a film-like crushed material that floats on the water and crushed material such as plastics and metals that sink to the bottom of the separation tank (81). This film-like pulverized material is conveyed to the dehydration process (dehydrator (4)) via a rinsing process (screw conveyor (3)) to remove moisture. In this dehydrator (4), the film-like pulverized material is rotated and centrifuged for dehydration while being twisted, so that the moisture contained within the film can also be easily removed.

[0014] In the washing and dehydration step (S3) (washing and dehydrating machine (2)), crushed waste plastics are fed into the inlet (26) and washed with water by the screw blades (24) in the washing tank (21). The washed crushed waste plastic pieces are transported by the same screw blades (24) to the dehydration tank (22) adjacent to the washing tank (21). Water adhering to the crushed waste plastic pieces falls off the semi-cylindrical screen (25) as they are transported by the screw blades (24) and is separated. The crushed waste plastic pieces are transported directly to the discharge port by the screw blades (24). In particular, the beating plate (28) attached to the screw blades (24) has the function of breaking up clumps of crushed waste plastic pieces being transported. When breaking up the clumps, the water scatters and can fall directly off the semi-cylindrical screen (25).

[0015] In the gravity separation process (gravity separator 8), the rotation of the rotary blades at the opening of the separation tank 81 causes the crushed materials such as plastics and metals mixed in the film-like crushed material to settle. The crushed materials that settle to the bottom of the separation tank 81 can be easily discharged by the screw shaft. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is an explanatory flow diagram showing each processing step constituting the method for crushing and cleaning waste of the present invention. [Figure 2] 1 is a front view showing a series of equipment for carrying out a method for crushing and cleaning waste materials. [Figure 3] FIG. 2 is a front view showing the washer-crusher and the washer-dehydrator. [Figure 4] FIG. [Figure 5] FIG. 2 is a front cross-sectional view of the washer / extractor. [Figure 6] FIG. 10 is an enlarged front view showing a screw blade with a striking plate attached thereto. [Figure 7] FIG. 2 is an enlarged cross-sectional view showing a screw blade with a striking plate attached thereto. [Figure 8] FIG. 2 is a front view showing a U-shaped screw conveyor. [Figure 9] FIG. [Figure 10] FIG. 2 is a front view showing the gravity separator. [Figure 11] FIG. 2 is an enlarged cross-sectional view showing the inlet of the gravity separator. [Figure 12] FIG. 2 is a front view showing the cyclone and the packaging bag. [Figure 13] FIG. 1 is a front view showing a vertical dehydrator for heavy plastics. [Figure 14] FIG. 1 is an explanatory flow diagram showing each processing step of a conventional method for crushing and cleaning waste. DETAILED DESCRIPTION OF THE INVENTION

[0017] The method for crushing and washing waste of the present invention comprises a crushing step for crushing plastic waste into a predetermined shape and size, a water washing step for removing dirt from the crushed waste, a dehydration tank having a semi-cylindrical screen with a large number of holes in the housing, a screw blade wound spirally around a rotating shaft that rotates in the dehydration tank, and a beating plate attached at one or more points along the length of one pitch (P) of the screw blade, which breaks up lumps of the crushed waste being transported, scatters moisture, and removes dirt from the crushed waste. This treatment method comprises a washing and dehydration process in which the floating particles are removed and the surface moisture is also removed; a gravity sorting process in which the crushed material is separated in a separation tank into floating particles and crushed particles of plastics, metals, etc. that sink to the bottom based on the difference in specific gravity; a rinsing process in which the crushed material is fed into a roughly cylindrical screw conveyor, where the moisture adhering to the surface of the crushed material is allowed to drip and is squeezed out to remove the moisture; and a dehydration process in which the crushed material is rotated and centrifuged while being twisted while air is intermittently sprayed onto it to remove the moisture adhering to the crushed material. [Example]

[0018] <Configuration of the method for crushing and cleaning waste> Preferred embodiments of the present invention will now be described with reference to the drawings. Fig. 1 is a flow chart showing each processing step constituting the method for crushing, cleaning and treating waste of the present invention, and Fig. 2 is a front view showing a series of facilities for carrying out the method for crushing, cleaning and treating waste. The crushing and washing treatment method of the present invention is a treatment method for plastic waste, which involves a crushing process S1 using a washer / crusher 1 and a water washing process S2, followed by a washing and dehydrating process S3 using a washer / dehydrator 2, a rinsing process S4 using a U-shaped screw conveyor 3, a dehydrating process using a horizontal dehydrator 4 as needed, and a gravity separation process S5 using a wet gravity separator 8 (separation water tank 81) via a blower 5, a cyclone 6, and a pushing screw 7.

[0019] The pulverized material separated in this gravity separation process S5 (wet gravity separator 8) undergoes a rinsing process S21 using a U-shaped screw conveyor 3, a dehydration process S22 using a horizontal dehydrator 4, and a drying process S23 using a blower 5 to produce recycled film-like plastics. In addition, the crushed plastics and metals that have been separated by settling in the gravity separation process S5 (wet gravity separator 8) are separated into plastic waste and crushed metals, etc. through a dehydration process S31 using a vertical dehydrator 10 and a manual sorting process S32. [Example]

[0020] <Configuration of the waste crushing and cleaning treatment device> FIG. 3 is a front view showing the washer-crusher and the washer-extractor. The washer-crusher 1 used in the crushing step is a device that crushes waste into crushed material of a predetermined shape and size using rotating blades. In the water washing step, dirt on the inside and outside surfaces of the waste crushed using this washer / crusher 1 is removed by washing with water. Note that it is not necessary to perform these crushing and water washing steps separately, and a crushing / washing step in which crushing and water washing are performed simultaneously can be adopted. In the crushing / washing treatment method of the present invention, in order to reduce the treatment time by half, the crushing / washing machine 1 is used to crush the waste into particles of a predetermined shape and size and simultaneously washes it with water.

[0021] <Configuration of the washer / extractor> Fig. 4 is a front view showing only the washer / extractor, and Fig. 5 is a front sectional view of the washer / extractor. The washer / extractor 2 used in the washing / extraction step has a washing tank 21 and an adjacent dehydration tank 22. It is equipped with a single rotating shaft 23 that penetrates both the washing tank 21 and the dehydration tank 22, and a screw blade 24 wound spirally around the rotating shaft 23. The dehydration tank 22 contains a semi-cylindrical screen 25 for dehydration. It also has a drive device such as a motor that rotates the rotating shaft 23. In the illustrated example, the washing tank 21 and the dehydration tank 22 are shown as separate structures, but they can be housed in the same apparatus body to form a compact structure (not shown).

[0022] The cleaning tank 21 is, for example, a roughly rectangular parallelepiped housing with an inlet 26 at the top for inserting crushed waste. It also has side and bottom plates to prevent the crushed waste from scattering. The side or bottom plates have drainage ports 27 for discharging cleaning water and dehydrated water to the outside.

[0023] In the cleaning tank 21, the crushed pieces of waste are washed with a liquid such as water while rotating a screw blade 24 wound spirally around a rotating shaft 23. The drive device that rotates the rotating shaft 23 (screw blade 24) is designed to rotate forward and backward.

[0024] A dehydration tank 22 is disposed adjacent to the washing tank 21. This dehydration tank 22 is a roughly rectangular parallelepiped housing with side panels, a top panel, and a bottom panel that prevent the pulverized pieces of waste being dehydrated from scattering. Furthermore, a semi-cylindrical screen 25 is provided below the screw blades 24 that are arranged to penetrate the interior. The semi-cylindrical screen 25 is a screen with many holes that remove moisture from the pulverized pieces of pulverized waste plastics.

[0025] The distance between the inner surface of the semi-cylindrical screen 25 and the outer edge of the spiral screw blade 24 is approximately 10 mm to 20 mm. This distance varies depending on the size of the pulverized waste pieces or the properties of the pulverized waste pieces. The distance can be varied depending on the type of material, such as soft plastics, hard or thick plastics, etc.

[0026] <Strike board configuration> Fig. 6 is an enlarged front view showing a screw blade with a striking plate attached, and Fig. 7 is an enlarged cross-sectional view showing a screw blade with a striking plate attached. The configuration of the screw blade 24 in the dewatering tub 22 is basically the same as the configuration of the screw blade 24 in the cleaning tub 21. The screw blade 24 arranged in the dewatering tub 22 has square-shaped striking plates 28 attached at several points.

[0027] The striking plates 28 are attached at two locations across one pitch (P) of the screw blade 24. In the illustrated example, three square striking plates 28 are attached to one screw blade 24.

[0028] The beating plate 28 is arranged with its plate plane aligned along the longitudinal direction of the screw blade 24 (rotation shaft 23) and along the radial direction of the rotation shaft 23. The beating plate 28 attached to the screw blade 24 has the function of breaking up clumps of the crushed material (crushed waste plastic pieces) being transported. When breaking up these clumps, water scatters and falls directly from the semi-cylindrical screen 25.

[0029] In the illustrated example, three striking plates 28 are attached to one screw blade 24 (rotary shaft 23). These three striking plates 28 are just one example, and the number of striking plates may be four or more or two or less depending on the length of one screw blade 24. In addition, in the illustrated example, the three striking plates 28 are arranged in a straight line along the axial direction of the screw blade 24, with one pitch (P) between them, but this is just one example, and they do not necessarily have to be arranged in a straight line. Also, they do not necessarily have to be arranged with one pitch (P) between them.

[0030] The square-shaped striking plate 28 of the present invention is shown positioned so that one side does not come into contact with the rotating shaft 23. This is because the original function of the screw blade 24 is a screw conveyor. It is not desirable for the striking plate 28 to interfere with the transport of the crushed material or its chunks. However, if the crushed material is large, it can be moved beyond the striking plate 28. Therefore, the square-shaped striking plate 28 may be attached so that one side comes into contact with the shaft surface of the rotating shaft 23.

[0031] The illustrated example shows the beating plate 28 as a flat plate, but it may also be a curved plate. Furthermore, while the illustrated example shows a square plate parallel to the axial direction of the rotating shaft 23, this is not necessarily limited to an exact rectangular shape. As long as it has the function of breaking up lumps of material to be crushed, it can be in various shapes such as a trapezoid, bow, or pentagon.

[0032] The striking plate 28 is arranged so that one side does not come into contact with the rotation shaft 23. The multiple striking plates 28 are arranged so that the distance between each plate and the inner surface of the semi-cylindrical screen 25 is the same.

[0033] Depending on the properties and size of the crushed material, the optimum distance between each beating plate 28 and the inner surface of the semi-cylindrical screen 25 is used. When the size of each side of the crushed material is nearly uniform, it is suitable to arrange the multiple beating plates 28 so that the distance between each plate and the inner surface of the semi-cylindrical screen 25 is the same distance (C).

[0034] <Screw conveyor (rinsing process) configuration> FIG. 8 is a front view showing a U-shaped screw conveyor. The screw conveyor 3 that performs the rinsing step of the present invention has a rotatable screw shaft inside a substantially cylindrical feeder body 31. This feeder body 31 is also substantially cylindrical, and has a cylindrical mesh plate on about half of its inlet 32 ​​side that drips water, and a tapered conical screen with slits formed in its longitudinal direction on about half of its outlet 33 side.

[0035] In this screw conveyor 3, a cylindrical mesh plate 21 located approximately halfway along the inlet 32 ​​side allows moisture adhering to the surface of the film-like crushed material to drip off. Next, a screen formed approximately halfway along the outlet 33 side of the screw conveyor 3 squeezes out and removes moisture adhering to the inside of the film. In particular, because the slits are formed in the longitudinal direction, they do not clog even when pressed forcefully by the screw shaft, allowing moisture to be removed. In other words, waste containing moisture can be rinsed away.

[0036] The discharge port 33 of the screw conveyor 3 is equipped with a slide flange 34 that opens when the rotation of the screw shaft moves the pulverized material toward the discharge port 33. This slide flange 34 is constantly pressed from the discharge port 33 side toward the input port 32 side by an elastic member such as a spring, so that the film-like pulverized material in the screen portion is not discharged from the discharge port 33 before it receives a predetermined pressure and the moisture is removed, thereby ensuring that the moisture can be removed reliably.

[0037] <Configuration of the dehydrator (dehydration process)> FIG. 9 is a front view showing the dehydration device. The dehydrator 4, which performs the dehydration process of the present invention, is configured with a rotating shaft with multiple spirally formed separators around its periphery, located within a cylindrical mesh plate with spiral ribs on its inner wall within a housing 41. This configuration changes the orientation of the crushed waste material to facilitate the removal of adhering moisture and shortens the processing time required to remove moisture adhering to the interior and exterior surfaces of the crushed waste material. Specifically, the rotating shaft with spirally formed separators rotates within the mesh plate with the spiral ribs. This prevents the film-like crushed waste material introduced through the inlet 42 from immediately moving to the outlet 43, thereby lengthening the residence time of the crushed waste material in the dehydrator 4 and ensuring the removal of moisture adhering to the material. The dehydrated water is discharged through the drain outlet 44.

[0038] Furthermore, the rotating shaft of the dehydrator 4 of the present invention is not simply plate-shaped, but has multiple dividing sections formed continuously in a spiral shape, so that the crushed waste material does not cling to the rotating shaft and can easily move within the dividing sections, thereby enabling moisture to be removed efficiently.

[0039] The cover of the dehydrator 4 is equipped with air purges at multiple locations that intermittently inject air toward the cylindrical mesh plate. By intermittently injecting air at the crushed waste material, these air purges change the orientation of the film-like crushed material, making it easier to remove any moisture that adheres to it. At the same time, they also prevent the mesh plate from clogging, preventing a decrease in dehydration efficiency.

[0040] <Configuration of gravity separator (gravity separation process)> Fig. 10 is a front view of the gravity separator, and Fig. 11 is an enlarged cross-sectional view of the inlet of the gravity separator. The crushed material from which water has been removed in this rinsing process is transported by screw conveyor 3 to the separating water tank 81 of the gravity separator 8, which is used in the next gravity separation process. As shown in Figures 2 and 9, a horizontal dehydrator 4 may be used at this time if necessary. In the separating water tank 81 of the gravity separator 8, the crushed and pulverized materials may clump together, which may result in an inaccurate specific gravity. Therefore, this is done to break up the clumps of crushed and pulverized materials and make it easier to separate them into those that float in the water and those that sink.

[0041] The gravity separator 8 separates crushed material into film-like crushed material and crushed material such as plastics and metals based on the difference in specific gravity in a separation water tank 81. This gravity separator 8 has a plurality of rotating blades attached to a rotating shaft that spans the width of the opening of the roughly rectangular parallelepiped separation water tank 81, which is filled with water, in the longitudinal direction of the opening, from an inlet 82 to an outlet 83. By rotating these rotating blades 13 from the inlet 82 to the outlet 83, the water is circulated and the film-like crushed material is separated while being transported to the outlet 83.

[0042] The film-like crushed material is sent from the washer / extractor 2 or horizontal extractor 4 to the separation water tank (feeding port 82) of the gravity separator 8 via the blower 5, cyclone 6 and pushing screw . By stirring and circulating the water from the inlet 82 to the outlet 83 near the water surface in the separation tank 81, not only is the floating film-like crushed material transported directly to the outlet 83, but crushed materials such as plastics and metals mixed in the film-like crushed material are also efficiently allowed to settle.

[0043] In the separating water tank 81, crushed materials such as plastics and metals that settle are transported to a discharge port 83 by a screw shaft installed at the bottom of the separating water tank 81. From this discharge port 83, the materials are transported to the next process via a screw conveyor 3.

[0044] In this embodiment, the tip of the inlet 82 is placed underwater in the separation tank 81, as shown in Figure 11. Conventionally, crushed material is dropped onto the water surface to separate it by specific gravity. In other words, the tip of the inlet is separated from the water surface. When film-like crushed material is added as a lump, clumps containing air bubbles tend to float, while clumps containing heavy plastics or metals tend to sink, making it difficult to perform accurate specific gravity separation. This is because adding crushed material, which tends to clump during dehydration, to water makes it easier to break up.

[0045] <Configuration of dehydration process 1 (vertical dehydrator for light plastics)> FIG. 12 is a front view showing the cyclone and the packing bag. In the gravity separator 8 (gravity separation step), the waste is separated into floating film-like waste and sinking plastic waste (heavy plastic) and metal waste. The floating film-like waste is passed through a U-shaped screw conveyor 3 in the rinsing process, and then through a separating water tank 81 in the gravity sorting process, where moisture adhering to the pulverized waste is removed.Furthermore, moisture adhering to the pulverized waste is removed in a horizontal dehydrator 4 in the dehydration process.

[0046] Next, the film-like pulverized material is dried using a blower 5 (drying blower) etc. After that, the film-like pulverized material is filled into a packing bag 12 using a cyclone 11, and the series of processing steps is completed in a state where it can be transported.

[0047] <Configuration of dehydration process 2 (vertical dehydrator for heavy plastics)> FIG. 13 is a front view showing a vertical dehydrator for heavy plastics. Meanwhile, the crushed material that has settled in the gravity separator 8 is centrifuged in a vertical dehydrator 10 or the like to remove moisture, and then separated into metals and plastics in a sorting process. The separated pulverized material can be further pulverized using a separate pulverizing device (not shown) depending on the contents, thereby producing plastic raw materials of various desired sizes.

[0048] It should be noted that the present invention is not limited to the above-described embodiments of the invention, and as long as it is a method or recycling processing device for recycling plastic raw materials by efficiently removing moisture adhering to the film-like crushed material of crushed waste, it is not limited to the configuration of the illustrated process, processing equipment or processing device, and can of course be modified in various ways within the scope of the gist of the present invention. [Industrial Applicability]

[0049] The apparatus for washing and dehydrating waste plastics of the present invention can be used mainly for recycling plastic containers, plastic products, or vinyl sheets for greenhouse cultivation. [Explanation of symbols]

[0050] S1 Crushing process S2 Water cleaning process S3 Washing and dehydration process S4 Rinse process S5 Gravity sorting process S22 Dehydration process S31 Dehydration process 1. Cleaning and crushing machine 2 Washing and dehydrating machine 22 Dehydration tank 23 Rotation axis 24 screw blade 25 Semi-cylindrical screen 28 Beating Board P 1 pitch 3 Screw conveyor 31 Feeder body 32 Inlet 33 Outlet 8 Gravity separator 81 Separation tank 82 Inlet 83 Outlet

Claims

1. A crushing step (S1) of crushing plastic waste into a predetermined shape and size; a water washing step (S2) for removing dirt from the pulverized waste material; a washing and dehydration step (S3) in which a screw blade (24) spirally wound around a rotary shaft (23) in a dehydration tank (22) having a semi-cylindrical screen (25) with a large number of holes drilled in the housing, and square plate-like beating plates (28) attached to two positions on the screw blade (24) so ​​as to span the rotary shaft (23) in the longitudinal direction over one pitch (P) of the screw blade (24) break up lumps of the pulverized material being conveyed, disperse moisture, remove dirt from the pulverized material, and remove surface moisture; A gravity separation step (S5) in which the pulverized material is separated into floating pulverized material and pulverized material such as plastics and metals that sink to the bottom of the water in a separation water tank (81) based on the difference in specific gravity; The method for crushing and cleaning waste material further comprises a dehydration step (S22, S31) in which the crushed material is twisted and rotated by centrifugation to remove moisture adhering to the crushed material while intermittently injecting air onto the crushed material.

2. 2. The method for crushing and cleaning waste according to claim 1, further comprising a rinsing step (S4) of feeding the crushed material into a substantially cylindrical screw conveyor (3) after the cleaning and dewatering step (S3), allowing the water adhering to the surface of the crushed material to drip off, and squeezing the water out to remove it.

3. a washing and crushing machine (1) that crushes waste into a predetermined shape and size and washes the crushed waste by spraying water while rotating the crushed waste; a screw conveyor-type washer / dehydrator (2) comprising: a dehydration tank (22) having a semi-cylindrical screen (25) with a large number of holes in the casing for removing dirt from the pulverized waste material and removing moisture from the surface; a screw blade (24) wound in a spiral shape around a rotating shaft (23) that rotates in the dehydration tank (22); and one or more square beating plates (28) attached to two locations on the screw blade (24) so ​​as to span the rotating shaft (23) in the longitudinal direction over one pitch (P) of the screw blade (24); a gravity separator (8) for separating the pulverized waste material into floating film-like pulverized material and pulverized material such as plastics and metals that sink to the bottom of the water in a separation tank (81) based on the difference in specific gravity; a screw conveyor (3) having a rotatable screw shaft in a substantially cylindrical feeder body (31), a cylindrical mesh plate for dripping water in about half of the feeder body (31) on the inlet (32) side, and a screen with slits formed in its longitudinal direction in about half of the feeder body (31) on the outlet (33) side; and a dehydrator (4) for rotating and centrifugal dehydrating the pulverized material transported by the screw conveyor (3) to remove moisture adhering to the pulverized material while twisting the pulverized material.

4. 4. The waste crushing, cleaning and treatment device according to claim 3, wherein a plurality of said beating plates (28) are attached to a screw blade (24) of said washer / dehydrator (2).

5. 4. The waste crushing and cleaning treatment device according to claim 3, wherein the beating plates (28) of the washer / dehydrator (2) are attached to two locations of the screw blades (24) within one pitch (P) of the screw blades (24) so ​​as not to come into contact with the rotary shaft (23).

6. The gravity separator (8) 4. The waste crushing and cleaning treatment device according to claim 3, wherein the opening of the separation water tank (81) is provided with a rotary blade which rotates on the water surface from the inlet (82) to the outlet (83), and a screw shaft which discharges crushed material which settles to the bottom of the separation water tank (81).

Images