JPH01146708A - Compression molding method for waste plastic and device thereof - Google Patents

Abstract

PURPOSE:To make the volume smaller and raise the efficiency of landfilling and discarding works by preliminarily softening crushed waste plastic in an atmosphere at a heat deformation temperature, heating the same in a compression molding chamber and then performing compression molding. CONSTITUTION:In the processes of crushing waste plastic by a crusher 2 and stirring and conveying only fragments selected by a selector 3 by a screw feeder 6, the waste plastic is softened by hot air regulated at 50-150 deg.C from a hot air producing device 7 and starts melting. Then, the waste plastic fed into a compression molding chamber 9 is piled up and softened and melted by blowing hot air of 150-200 deg.C from the hot air producing device 7. Next, a cylinder A is actuated and the heaped plastic is compressed and crushed by a press 13 and cylinders B and C are actuated to compress the plastic from left and right in the central section of the molding chamber 9 by presses 14 and 15. Then, a block 17 is pushed to a given position by the cylinders B and C, and a cylinder D is operated to actuate a press 18 to melt and solidify the surface layer of the block 17 and put the same into hot rollers 19 heated up to 200-400 deg.C and pushed outside.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Industrial Application Field The present invention relates to a method and apparatus for compression molding waste plastic, which preheats and dries plastic waste to reduce its weight and then form blocks and reduce its volume. be.

(b) Conventional technology In the conventional technology, the softening temperature of waste plastic varies depending on the type, so if an inappropriate temperature is applied, some types will melt, making mechanical operation difficult. In this process, waste mainly composed of thermoplastic plastics is compressed and pressed at room temperature without applying heat to the waste plastics, but blocks compressed under such conditions are compressed to allow the plastic to expand and recover after being press-molded. Because the blocks may burst, collapse, or scatter, it has been difficult to reduce the volume effectively, as it is necessary to prevent the blocks from expanding and restoring.

(c) Problems to be Solved by the Invention As mentioned above, the present invention has the following advantages: - Compression molding that does not expand or restore waste plastic that expands and restores itself over time and is difficult to form into regular blocks even when compressed A compression molding method for waste plastic, which can reduce the volume of the waste plastic block as much as possible, and improve the efficiency of loading and unloading at landfills, decoy work, etc. It is intended to obtain equipment.

(=) Means for Solving the Problems The present invention was made by focusing on such conventional problems, and consists of (1) a crushing process for crushing waste plastics, and a process for crushing waste plastics crushed by the crushing process; Stirring preheating step of preheating the plastic at about 50°C to 1500°C while stirring, and adding a predetermined amount of preheated waste plastic to about 1000°C to 20°C
It is softened or partially melted by blowing hot air at 00℃ and becomes white.
A heating compression step of compressing the waste plastic into an L-shape, and heating the surface layer of the heated and compressed waste plastic to approximately 2000°C to 4000°C''''C.
A compression molding method for waste plastic, which comprises a melting and carrying out step of carrying out the waste plastic while melting and solidifying it, and (2) a transfer chamber having a means for stirring the crushed input waste plastic and a means for blowing hot air at a required temperature. , a compression molding chamber that receives the waste plastic that has been stirred and preheated by the transfer chamber, and has hot air blowing means at a required temperature and compression means from three directions; a surface layer of the block compressed in the compression molding chamber; An object of the present invention is to provide a compression molding apparatus for waste plastics, which comprises an extrusion section having a means for melting and conveying at a temperature of .

(f) Embodiment and operation The operation and operation will be explained below with reference to the drawings showing the configuration of an embodiment of the present invention.

As shown in FIG. 1, waste plastic is transported from a garbage pit 1 to a crusher 2 and crushed, and a sorter 3 separates only the magnetic pieces of the waste plastic from the supply port 5 of the transport chamber 4.
It is stirred and conveyed by the knee feeder 6. So.

During the process, a temperature controller TC detects the temperature of the 0111° blowing pipe 8 sent from the hot air generator 7.

The waste plastic fragments are preheated evenly in the transfer chamber 4 by hot air at a temperature of 50 to 150°C, which is adjusted by adjusting the temperature control valve TCV and appropriately mixing atmospheric air, thereby drying out adhering moisture and organic matter. removed.

In this stirring and conveying process, if the hot air sent from the hot air generator 7 is selected to be as low as 100°C or less, the waste plastic will be preheated and softened to some extent.

Furthermore, if a temperature of 100 to 150° C. is selected, the thermoplastic waste plastic ivy softens and begins to melt, depending on the time it takes to pass through the above steps.

Without this preheating in the transfer chamber 4, it would be difficult to heat the inside of the piled up waste plastics thrown into the compression molding chamber 9.

Next, the waste plastics in the above state put into the compression molding chamber 9 are piled up in a certain amount for one process in the compression molding chamber 9, and the hot air sent from the hot air generator 7 to the compression molding chamber 9 is compressed. Temperature controller TC that detects the temperature of the molding chamber 9
Hot air of 150 to 200°C, whose temperature was adjusted by adjusting the temperature control valve TCV2 according to 2 and appropriately mixing air, was blown from the hot air blowing nozzle 10 on the side wall of the compression molding chamber 9 and heated. Thermoplastics soften and melt.

The molten waste plastic surrounds the unsoftened waste plastic, solidifies it, suppresses expansion and restoration, and increases the compressed density.

Next, when the supply of waste plastic ink is stopped and the compression molding process begins, cylinder A is activated first, as shown in FIG. 2, and gate 12 closes outlet 11 of transfer chamber 4, and When the valve S is switched to the exhaust side, the breather 13 compresses and eliminates the pile of waste plastic, and then the cylinders B and C
are operated at the same time, and the presses 14 and 15 compress from the left and right sides in the center of the compression molding chamber 9, as shown in FIG.

Depending on the material of the waste plastic fragments present on the surface of the compression-molded waste plastic block, the main components may be polyethylene, polypropylene, polyvinyl chloride, polystyrene, etc., such as waste plastic from municipal waste. In this case, it will be in a molten state by 180°C, although it depends on the time of the compression molding process, so in this case, the appropriate temperature of the hot air will be selected to be 150 to 160°C.

Hard plated thin plates 16 are attached to both sides of the compression molding chamber 9, the bottom surface, the compression surfaces of the presses 14 and 15, and the compression surfaces of the brace 13, so that the compression molded blocks can be easily peeled off. When the waste plastic is compressed in the compression molding chamber 9, the molten thermoplastic plastic surrounds other poorly softened solids and forms a block.

Next, regarding the surface treatment of the compression-molded block, cylinder B is further extended and cylinder ○ is retracted to move the block 17 from the position shown in Figure 3 to the position shown in Figure 4.
is pressed, the cylinder D is operated, and the block 17 is heated to 200 to 400° C. in a hot row of 5-19 days to melt and solidify the surface layer and extrude it to the outside.

In this case, the mechanical installation of the hot rollers 19 is such that the rotating direction of all the hot rollers 19 is in the direction shown in FIG. 9 through gears 20 as shown in FIGS. 6 and 7. The hot roller 19 and gear 20 are supported by bearings 21 and 22, respectively.

Further, a scraping device 23 is provided to scrape off any waste plastic that is fused to the hot roller 19 when the surface layer of the block is melted and make it adhere to the block. Incidentally, a hot plate 24 is attached to the front and rear walls of the extruded portion of the block 17. Also, Figure 6,
In the case shown in FIG. 7, all of the hot rollers 19 are rotationally driven by the motor 25 to help extrude the block 17. It may be arranged to fall naturally in accordance with the melting speed of the surrounding four sides of 17.

On the other hand, as shown in FIG. 11, when preheating is performed by configuring the stirring and preheating steps in the transfer chamber 4 and the screw feeder 6 in multiple stages, the preheating is completely performed and the compression molding chamber 9
The molding process is also facilitated.

The molded block is in a heat storage state, and heat is not transferred to the inside of the block during extrusion by hot rollers 19 on the surface layer, so that melting and assimilation is rapid and good.

When melting and solidifying the surface layer of a block compression-molded at room temperature, external heating takes a very long time because the block absorbs heat first.

50-100°C first by screw feeder 6
Next stirring, preheating and compression molding chamber 9 at 150-160°
The secondary heating of C is very important, and the hot air 5 in the transfer chamber 4
Waste plastic temperature is 50-100°C compared to 0-150°C.
Hot air preheated to 150-200 °C and into the compression molding chamber 9
It is thought that waste plastics are heated to 150 to 160°C to melt polyethylene, polypropylene, polyvinyl chloride, polystyrene, etc. “
' Also, the stirring and preheating by the screw feeder 6 affect the heating effect in the compression molding chamber 9.

In addition, it is also possible to install a hot plate 24 on the entire wall surface of the extrusion section as shown in FIG. 10 instead of the hot roller 19 described above. Since it falls naturally, a good block surface can be obtained.

Next, when the waste plastic is compression molded by the method described above, the block 17 accumulates heat and takes a considerable amount of time to cool down. The conveyor 26 drains, transports, and cools the material.

As shown in FIG. 6, the extrusion portion of the block 17 has an opening/closing bottom 27 that is closed by a weight 28, and is opened by the weight of the block 17, and is returned to the closed state by the weight 28 after extrusion.

An exhaust gas nozzle 29 is disposed at a communication port that communicates with the supply port 5 of the cleaning device 24, the compression molding device, etc., and the dust collection and deodorization equipment 3 is passed from these through an exhaust gas pipe 30.
1 to remove dust and odors.

(f) Effects of the Invention As is clear from the above explanation, the present invention is based on the method of softening waste plastics by preheating them in an atmosphere with a heat deformation temperature before gas generation, and then processing the waste plastics in a compression molding chamber. After heating, compression molding is performed using a press.
As a result, compression-molded waste plastics can be effectively reduced in volume without expanding and restoring.

In addition, by selecting a common heat distortion temperature for each of the many types of waste plastics, it is possible to melt thermoplastics while minimizing the generation of harmful thermal decomposition products, and to melt other unmelted solids, such as Welded to thermosetting resin, pebbles, glass magnetic pieces, etc., and penetrated into the cavity inside the block to eliminate the cavity inside the block as much as possible, and the surface layer was sufficiently melted and solidified. It is possible to perform very effective i-solubilization that strengthens the strength of the material, and it is extremely rational and economical because it is simple and easy to handle, making it possible to improve the efficiency of loading and unloading for landfill disposal and transportation work.

[Brief explanation of the drawing]

Fig. 1 is a simplified flow sheet showing the processing steps of one embodiment of the present invention, and Figs. 2, 3, and 4 are explanatory diagrams of the compression molding process of waste plastics, showing longitudinal cross-sectional views at the start of compression molding. , Figure 2 is a state diagram of a softened waste plastic block at the start of compression molding in the compression molding chamber, and Figure 3 is a state diagram of a softened waste plastic block compressed from both sides by a press.
FIG. 4 is a state diagram in which a block of compressed waste plastic is moved to the right side and then extruded from above using a press and moved into the gtE. Fig. 5 is a schematic three-dimensional view of the main body of the apparatus for implementing the method of the present invention, Fig. 6 is a sectional view showing the arrangement of the hot roller, its rotational drive mechanism, and the opening/closing mechanism of the opening/closing bottom. The right side view of the same, Figure 8 is an explanatory diagram of the state in which the gate equipped on the press blocks the exit of the transfer chamber, and Figure 9 is an explanatory diagram of the state in which the exit of the transfer chamber is blocked by the gate equipped on the press. A cross-sectional view showing the arrangement of a scraping device for redeposition; FIG. 10 is a cross-sectional view when only the hot plate is attached to the inner wall of the extrusion part;
FIG. 11 is a simplified explanatory diagram of another embodiment in which waste plastic is stirred, preheated, and transported by a plurality of screw feeders. 1...garbage bit, 2...crusher, 3...
Sorter, 4... Transfer chamber, 5... Supply port, 6... Screw feeder, 7... Hot air generator, 8...
Hot air blowing pipe, 9... Compression molding chamber, 10... Hot air blowing nozzle, 11... Transfer chamber outlet, 12... Gate, 13... Press, 14... Press, 15 ...
Press, 16... Plated thin plate, 17... Block,
1st...press, 19...hot roller, 20.
...Gear, 21.22...Bearing, 23...Scraping device, 24...Hot plate, 25...Motor, 26...Conveyor, 27...Opening/closing bottom, 2nd...・
Weight, 29...Exhaust gas nozzle, 30...Exhaust gas pipe, 31...Dust collecting and deodorizing equipment, A...Cylinder, B...Cylinder, C...Cylinder, D...Cylinder , TC, ... Temperature control device, TC, ... Temperature control device, S■ ... Solenoid valve,
TCV...Temperature control valve, TCV2...Temperature control valve. Figure 2 Figure 3 Figure 6 Figure 7 Figure I Figure 8 Figure 9 Figure 10

Claims (2)

[Claims] (1) A crushing process in which waste plastic is crushed, and while stirring the waste plastic crushed in the crushing process,
A stirring preheating step of preheating at 0°C to 1500°C, and a predetermined amount of the preheated waste plastic to about 1000°C to 2000°C.
A heating compression process in which hot air is blown to soften or partially melt the plastic and compress it into a block shape, and a melting process in which the surface layer of the heated and compressed waste plastic is melted and solidified at approximately 2000°C to 4000°C and then transported outside. A compression molding method for waste plastic, characterized by comprising the steps of: (2) A transfer chamber having a means for stirring the input waste plastic that has been crushed and a means for blowing hot air at a desired temperature, which receives the waste plastic that has been stirred and preheated by the transfer chamber, and blows hot air at the desired temperature. A compression molding chamber having a compression molding means and a compression means from three directions, and an extrusion section having a means for melting and transporting the surface layer of the block compressed in the compression molding chamber at a required temperature. Compression molding equipment.