A mixing device based on plastic waste recycling

Abstract

The application relates to the technical field of plastic recycling, in particular to a mixing device based on plastic waste recycling, which comprises a mixing body, a motor fixedly connected to the top of the mixing body, a mounting frame fixedly connected to the bottom of the output shaft of the motor, a rotating shaft fixedly connected to the bottom of the mounting frame, a sliding sleeve slidably connected to the outer side of the rotating shaft, stirring plates fixedly connected to the outer side of the sliding sleeve in an array, a liquid pipe fixedly connected to the inside of the rotating shaft, and a cold liquid assembly arranged in the mixing body, wherein the cold liquid assembly comprises a liquid inlet cavity formed in the bottom of the inside of the liquid pipe, and a liquid return cavity formed in the top of the inside of the liquid pipe. Through cooperation of the above structure, physical softening of plastic particles caused by friction during stirring can be prevented, excessive deformation or even adhesion of the plastic particles under the action of shearing force can be avoided, the uniformity of the particle size distribution of the mixing system can be maintained, and the quality of the plastic waste recycling product produced subsequently can be improved.

Description

Technical Field

[0001] This invention relates to the field of plastic recycling technology, specifically to a mixing device based on the recycling of plastic waste. Background Technology

[0002] In the process of recycling plastic waste, it is necessary to crush the plastic waste first. Premixing the crushed particles is a key preliminary step to ensure the stability of subsequent processes and the quality of recycled products. On the one hand, the sources of recycled plastic waste are complex, and there are natural differences in composition, density and particle size between different batches and types of crushed particles. Premixing can break the inhomogeneity of materials, allowing various particles to fully blend and form a uniform mixture. This avoids performance fluctuations during subsequent melting and plasticizing due to local component deviations, and lays a solid foundation for the consistency of the performance of recycled materials.

[0003] When mixing plastic granules, the friction generated by rapid stirring causes the plastic granules to soften physically. The softened plastic granules lose their original rigidity due to the intensified movement of molecular chain segments, and are prone to excessive deformation or even adhesion under shear force, which destroys the uniformity of particle size distribution of the mixed system. This leads to local melt viscosity differences in the subsequent melting and plasticizing stage, affecting the consistency of the mechanical properties of the recycled material. Summary of the Invention

[0004] The purpose of this invention is to provide a mixing device based on the recycling of plastic waste, so as to solve the problem of plastic particles sticking together during mixing as mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a mixing device for recycling plastic waste, comprising a mixing body, a motor fixedly connected to the top of the mixing body, a mounting bracket fixedly connected to the bottom of the motor's output shaft, a rotating shaft fixedly connected to the bottom of the mounting bracket, a sliding sleeve slidably connected to the outer side of the rotating shaft, an array of stirring plates fixedly connected to the outer side of the sliding sleeve, a liquid pipe fixedly connected to the inside of the rotating shaft, and a cooling liquid assembly disposed inside the mixing body, the cooling liquid assembly including a liquid inlet chamber opened at the bottom of the inner side of the liquid pipe. A return chamber is provided at the top of the inner side of the liquid tube. The interiors of the multiple stirring plates are hollow. A connecting pipe is fixedly inserted between adjacent stirring plates on the same side. An inlet pipe is fixedly inserted between the interior of the inlet chamber and one of the stirring plates on the same side. A return pipe is fixedly inserted between the interior of the return chamber and one of the stirring plates on the same side. Two round pipes are fixedly inserted inside the liquid tube. A rotary joint is installed at the bottom of the two round pipes. The top of one round pipe extends into the interior of the inlet chamber, and the top of the other round pipe extends into the interior of the return chamber.

[0006] Preferably, a liquid-driving assembly is disposed at the top inner side of the mixing body. The liquid-driving assembly includes a semi-ring frame fixedly connected to the top inner side of the mixing body. The liquid-driving assembly also includes a first piston movably connected inside the mounting frame. A vertical shaft is fixedly connected to the top centrifugal position of the first piston. A circular sleeve is fixedly connected to the inner side of the mounting frame. A second piston is movably connected inside the circular sleeve. A spring is fixedly connected between the second piston and the circular sleeve.

[0007] Preferably, a lifting shaft is fixedly connected to the bottom of the second piston, a lifting frame is fixedly connected to the bottom of the lifting shaft, and a third piston is fixedly connected to the bottom of the lifting frame extending into the interior of the liquid tube, the third piston moving inside the liquid tube.

[0008] Preferably, the circular tube extending into the return fluid chamber is equipped with a first check valve, and the return fluid fitting is equipped with a second check valve.

[0009] Preferably, a curved frame is fixedly connected to the outer side of the lifting frame, and the bottom of the curved frame is fixedly connected to the sliding sleeve.

[0010] Preferably, the portions of the return pipe and the inlet pipe located outside the sliding sleeve are made of rigid material, while the portions of the return pipe and the inlet pipe located inside the sliding sleeve are made of flexible material.

[0011] Preferably, the rotating shaft has a slot near the return pipe and the inlet pipe.

[0012] Preferably, one of the inlet pipes is inserted into the bottom stirring plate, and the other inlet pipe is inserted into the top stirring plate.

[0013] Preferably, a mixing assembly is disposed below the third piston. The mixing assembly includes a liquid tank fixedly connected to the bottom of the mixer body. A semiconductor cooling chip is installed at the bottom of the liquid tank. The liquid tank is connected to the rotary joint through a pipeline. A rotating rod is rotatably connected inside the liquid tank. A moving rod is movably connected inside the rotating rod. A guide spiral groove is formed on the inner side of the rotating rod. A guide slider is fixedly connected to the outer side of the moving rod. The guide slider moves inside the guide spiral groove. A straight rod is fixedly connected below the third piston. The bottom of the straight rod extends from the liquid pipe and is fixedly connected to the moving rod. A stirring blade is fixedly connected to the outer side of the rotating rod.

[0014] Preferably, the bottom of the liquid tank is made of copper.

[0015] Compared with the prior art, the beneficial effects of the present invention are:

[0016] 1. This invention can achieve circulating cooling, and with the stirring plate stirring inside the plastic particles, it can effectively cool the mixed plastic particles, prevent the friction generated by stirring from causing physical softening of the plastic particles, avoid excessive deformation or even adhesion of the plastic particles under shear force, destroy the uniformity of particle size distribution of the mixed system, and improve the quality of the plastic waste recycling products produced subsequently.

[0017] 2. This invention allows the bending frame to reciprocate in the vertical direction. This design allows the sliding sleeve to carry the stirring plate in the vertical direction to reciprocate. On the one hand, this allows for mixing at different locations, improving the quality of mixing. On the other hand, it allows the stirring plate to move to different positions, which is beneficial for cooling the plastic particles at different locations, improving the uniformity of cooling, further reducing the physical softening and adhesion of plastic particles, and further improving the quality of the subsequent plastic waste recycling products.

[0018] 3. In this invention, the coolant can enter from the upper stirring plate on one side and from the lower stirring plate on the other side. This design can reduce the situation where the temperature of the coolant gradually increases during the cooling process, which affects the uniformity of subsequent cooling. It can also reduce the physical softening and adhesion of plastic particles, thereby improving the quality of the plastic waste recycling products produced later.

[0019] 4. This invention enables the rotating rod to rotate with the stirring plate, mixing the cooling liquid inside the liquid tank, ensuring uniform cooling liquid temperature, which is beneficial for uniform cooling liquid temperature entering the stirring plate and ensuring the subsequent cooling effect. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0021] Figure 2 This is a schematic diagram of the half-section structure of the present invention;

[0022] Figure 3 This is a partial structural schematic diagram of the coolant assembly of the present invention;

[0023] Figure 4 This is a rear view schematic diagram of the stirring plate of the present invention;

[0024] Figure 5 This is a schematic diagram of the top half-section structure of the rotating shaft of the present invention;

[0025] Figure 6 This is a schematic diagram of a half-section of the first piston of the present invention;

[0026] Figure 7 This is a schematic diagram of the bottom half-section structure of the rotating shaft of the present invention;

[0027] Figure 8 This is a side view of the liquid tank structure of the present invention;

[0028] Figure 9 This is a side sectional view of the liquid tank of the present invention;

[0029] Figure 10 This is a partial structural schematic diagram of the guide slider of the present invention.

[0030] In the attached diagram, the components represented by each number are as follows:

[0031] 1. Mixing body; 2. Motor; 3. Mounting bracket; 4. Rotating shaft; 5. Sliding sleeve; 6. Cooling liquid assembly; 61. Inlet chamber; 62. Return chamber; 63. Connecting pipe; 64. Return fitting; 65. Circular pipe; 66. Rotary joint; 67. Inlet fitting; 7. Liquid driving assembly; 71. Semi-ring frame; 72. First piston; 73. Vertical shaft; 74. Circular sleeve; 75. Second piston; 76. Spring; 77. Lifting shaft; 78. Lifting frame; 79. Third piston; 710. First check valve; 711. Second check valve; 712. Bending frame; 713. Empty tank; 8. Mixing assembly; 81. Liquid tank; 82. Semiconductor cooling chip; 83. Rotating rod; 84. Moving rod; 85. Guide spiral groove; 86. Straight rod; 87. Guide slider; 88. Stirring blade; 9. Liquid pipe; 10. Stirring plate. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] This invention provides a technical solution: such as Figure 1 - Figure 10The mixing device shown is for recycling plastic waste. It includes a mixing body 1, a motor 2 fixedly connected to the top of the mixing body 1, a mounting bracket 3 fixedly connected to the bottom of the output shaft of the motor 2, a rotating shaft 4 fixedly connected to the bottom of the mounting bracket 3, a sliding sleeve 5 slidably connected to the outer side of the rotating shaft 4, an array of stirring plates 10 fixedly connected to the outer side of the sliding sleeve 5, a liquid pipe 9 fixedly connected inside the rotating shaft 4, and a cooling liquid assembly 6 disposed inside the mixing body 1. The cooling liquid assembly 6 includes an inlet chamber 61 located at the bottom of the inner side of the liquid pipe 9, and a return chamber 62 located at the top of the inner side of the liquid pipe 9. The interior of multiple stirring plates 10 is hollow. A connecting pipe 63 is fixedly inserted between adjacent stirring plates 10 on the same side. An inlet pipe 67 is fixedly inserted between the interior of the liquid inlet chamber 61 and one of the stirring plates 10 on the same side. A return pipe 64 is fixedly inserted between the interior of the return chamber 62 and one of the stirring plates 10 on the same side. Two round pipes 65 are fixedly inserted inside the liquid pipe 9. A rotary joint 66 is installed at the bottom of the two round pipes 65. The top of one round pipe 65 extends into the interior of the liquid inlet chamber 61, and the top of the other round pipe 65 extends into the interior of the return chamber 62.

[0034] A liquid-driving assembly 7 is disposed at the top inner side of the mixing body 1. The liquid-driving assembly 7 includes a semi-ring frame 71 fixedly connected to the top inner side of the mixing body 1. The liquid-driving assembly 7 also includes a first piston 72 movably connected inside the mounting frame 3. A vertical shaft 73 is fixedly connected to the top centrifugal position of the first piston 72. A circular sleeve 74 is fixedly connected to the inner side of the mounting frame 3. A second piston 75 is movably connected inside the circular sleeve 74. A spring 76 is fixedly connected between the second piston 75 and the circular sleeve 74. A lifting shaft 77 is fixedly connected to the bottom of the second piston 75. A lifting frame 78 is fixedly connected to the bottom of the lifting shaft 77. A third piston 79 is fixedly connected to the bottom of the lifting frame 78, which extends into the liquid pipe 9. The third piston 79 moves inside the liquid pipe 9. A first check valve 710 is installed in the circular pipe 65, which extends into the return liquid chamber 62. A second check valve 711 is installed inside the return liquid fitting 64.

[0035] It should be noted that the bottom of the semi-ring frame 71 is inclined, and the top of the vertical shaft 73 is rotatably connected with a ball to reduce frictional damping.

[0036] It should be noted that an opening is provided at the bottom of the ring side of the mixer body 1, and a blocking door is hinged to the opening for material discharge.

[0037] The rotary joint 66 has two passages. This technology is a mature existing technology and will not be described in detail. One passage is for the inlet of cooling liquid and the other passage is for the outlet of cooling liquid.

[0038] With the above technical solution, when in use, plastic particles are added to the inside of the mixer body 1, and then the output shaft of the motor 2 is rotated, which causes the mounting frame 3 to rotate with the rotating shaft 4 and the sliding sleeve 5, so that the stirring plate 10 can rotate to mix the crushed plastic particles.

[0039] During the mixing process, the rotation of the mounting frame 3 causes the first piston 72 and the vertical shaft 73 to rotate accordingly. When the vertical shaft 73 rotates to the position of the semi-ring frame 71, the limiting action of the semi-ring frame 71 causes the vertical shaft 73 to move downward with the first piston 72. At this time, the medium inside the mounting frame 3 located below the first piston 72 is pushed into the interior of the sleeve 74. Under the pressure of the liquid medium, the second piston 75 causes the lifting shaft 77 to move downward against the elastic force of the spring 76, and the lifting frame 78 moves downward accordingly. When the vertical shaft 73 rotates away from the position of the semi-ring frame 71, the elastic force of the spring 76 causes the liquid medium to return to the interior of the mounting frame 3, allowing the vertical shaft 73 to move upward with the first piston 72 to reset. This design allows the lifting frame 78 to move in the vertical direction.

[0040] With the combined action of the first check valve 710 and the second check valve 711, the cooling liquid can enter the return chamber 62 from the return pipe 64, flow from the return chamber 62 into the circular pipe 65 extending into the return chamber 62 and then be discharged, thus realizing the unidirectional flow of the cooling liquid.

[0041] This design allows the lifting frame 78 to move the third piston 79 vertically during the mixing process. Due to the suction and pushing action of the third piston 79, external cooling liquid can enter through one passage of the rotary joint 66, enter the liquid inlet chamber 61 through the circular pipe 65 extending into the liquid inlet chamber 61, and enter the stirring plate 10 through the inlet pipe 67. Under the action of the connecting pipe 63, the cooling liquid can enter the interior of multiple stirring plates 10 in sequence. Then, the cooling liquid enters the liquid return chamber 62 through the return pipe 64, and then exits through another passage of the rotary joint 66 through the circular pipe 65 extending into the liquid return chamber 62. This design can achieve circulating cooling, and together with the stirring plate 10 stirring inside the plastic particles, it can effectively cool the mixed plastic particles, prevent the plastic particles from being physically softened due to friction generated by stirring, avoid excessive deformation or even adhesion of plastic particles under shear force, and prevent damage to the uniformity of particle size distribution of the mixed system, thereby improving the quality of the plastic waste recycling products produced later.

[0042] A curved frame 712 is fixedly connected to the outside of the lifting frame 78. The bottom of the curved frame 712 is fixedly connected to the sliding sleeve 5. The parts of the return pipe 64 and the inlet pipe 67 located outside the sliding sleeve 5 are made of rigid material, while the parts of the return pipe 64 and the inlet pipe 67 located inside the sliding sleeve 5 are made of flexible material. A slot 713 is provided on the rotating shaft 4 near the return pipe 64 and the inlet pipe 67.

[0043] Through the above technical solution, this design allows the lifting frame 78 to move up and down during the mixing process, while the bending frame 712 moves back and forth in the same direction. This design also allows the sliding sleeve 5 to move back and forth with the stirring plate 10 in the same direction. This allows for mixing at different locations, improving the quality of the mixing process. Furthermore, it allows the stirring plate 10 to move to different positions, facilitating the cooling of plastic particles at different locations. This improves the uniformity of cooling, further reduces the physical softening and adhesion of plastic particles, and further improves the quality of the recycled plastic waste products produced later.

[0044] One of the inlet pipes 67 is inserted into the bottom stirring plate 10, and the other inlet pipe 67 is inserted into the top stirring plate 10.

[0045] With the above technical solution, in this design, the coolant on one side enters from the upper stirring plate 10, and the coolant on the other side enters from the lower stirring plate 10. This design can reduce the situation where the temperature of the coolant gradually increases during the cooling process, thus affecting the uniformity of subsequent cooling. It can also reduce the physical softening and adhesion of plastic particles, thereby improving the quality of the plastic waste recycling products produced later.

[0046] Below the third piston 79 is a mixing assembly 8, which includes a liquid tank 81 fixedly connected to the bottom of the mixer body 1. A semiconductor cooling chip 82 is installed at the bottom of the liquid tank 81. The liquid tank 81 is connected to the rotary joint 66 through a pipeline. A rotating rod 83 is rotatably connected inside the liquid tank 81. A moving rod 84 is movably connected inside the rotating rod 83. A guide spiral groove 85 is opened on the inner side of the rotating rod 83. A guide slider 87 is fixedly connected to the outer side of the moving rod 84. The guide slider 87 moves inside the guide spiral groove 85. A straight rod 86 is fixedly connected below the third piston 79. The bottom of the straight rod 86 extends from the liquid pipe 9 and is fixedly connected to the moving rod 84. A stirring blade 88 is fixedly connected to the outer side of the rotating rod 83. The bottom of the liquid tank 81 is made of copper.

[0047] It should be noted that a sealing ring is installed near the straight rod 86 on the liquid tube 9 to ensure the airtightness at that location. The semiconductor cooling chip 82 is a mature existing technology and will not be described in detail.

[0048] Through the above technical solution, the liquid tank 81 is filled with liquid for cooling. As the third piston 79 moves the straight rod 86 in the up-down direction, the moving rod 84 can reciprocate in the up-down direction. At this time, relative motion is generated between the moving rod 84 and the rotating rod 83. The guide slider 87 moves inside the guide spiral groove 85, which allows the rotating rod 83 to rotate with the stirring plate 88 to mix the cooling liquid inside the liquid tank 81, ensuring that the cooling liquid temperature is uniform. This is beneficial for the uniform temperature of the cooling liquid entering the stirring plate 10, ensuring the subsequent cooling effect.

[0049] Working principle: When in use, plastic granules are added to the inside of the mixer body 1, and then the output shaft of the motor 2 is rotated, which causes the mounting frame 3 to rotate along with the rotating shaft 4 and the sliding sleeve 5. This allows the mixing plate 10 to rotate and mix the crushed plastic granules.

[0050] When the vertical shaft 73 rotates to the position of the semi-ring frame 71, the limiting action of the semi-ring frame 71 allows the vertical shaft 73 to move downward with the first piston 72. At this time, the medium inside the mounting bracket 3 located below the first piston 72 is pushed into the interior of the sleeve 74. Under the pressure of the liquid medium, the second piston 75 can move downward with the lifting shaft 77, overcoming the elastic force of the spring 76. The lifting frame 78 then moves downward. When the vertical shaft 73 rotates away from the position of the semi-ring frame 71, the elastic force of the spring 76 causes the liquid medium to return to the interior of the mounting bracket 3, allowing the vertical shaft 73 to move upward with the first piston 72 to reset. This design allows the lifting frame 78 to move downward. The lifting frame 78 moves vertically, and the lifting frame 78 can move the third piston 79 vertically. Due to the suction and pushing action of the third piston 79, the external cooling liquid can enter from one passage of the rotary joint 66, and enter the interior of the inlet chamber 61 through the round pipe 65 extending into the inlet chamber 61, and enter the interior of the stirring plate 10 through the inlet pipe 67. Under the action of the connecting pipe 63, the cooling liquid can enter the interior of multiple stirring plates 10 in sequence. Then the cooling liquid enters the interior of the return chamber 62 through the return pipe 64, and then the cooling liquid is discharged from another passage of the rotary joint 66 through the round pipe 65 extending into the return chamber 62.

[0051] During the mixing process, when the lifting frame 78 moves in the vertical direction, the bending frame 712 can reciprocate in the vertical direction. This design allows the sliding sleeve 5 to carry the stirring plate 10 in the vertical direction to reciprocate. This allows for mixing at different locations, improving the quality of mixing. On the other hand, it allows the stirring plate 10 to move to different positions, which is beneficial for cooling the plastic particles at different locations.

[0052] As the third piston 79 moves the straight rod 86 in the vertical direction, the moving rod 84 can reciprocate in the vertical direction. At this time, the moving rod 84 and the rotating rod 83 generate relative motion. The guide slider 87 moves inside the guide spiral groove 85, which allows the rotating rod 83 to rotate with the stirring plate 88 to mix the cooling liquid inside the liquid tank 81 and ensure that the cooling liquid temperature is uniform.

[0053] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus.

[0054] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mixing device for recycling plastic waste, comprising a mixing body (1), wherein a motor (2) is fixedly connected to the top of the mixing body (1), a mounting bracket (3) is fixedly connected to the bottom of the output shaft of the motor (2), a rotating shaft (4) is fixedly connected to the bottom of the mounting bracket (3), a sliding sleeve (5) is slidably connected to the outer side of the rotating shaft (4), a stirring plate (10) is fixedly connected to the outer side of the sliding sleeve (5), and a liquid pipe (9) is fixedly connected inside the rotating shaft (4), characterized in that, Also includes: A cooling liquid assembly (6) is disposed inside the mixing body (1). The cooling liquid assembly (6) includes an inlet chamber (61) opened at the bottom of the inner side of the liquid pipe (9). A return chamber (62) is opened at the top of the inner side of the liquid pipe (9). The interiors of multiple stirring plates (10) are hollow. A connecting pipe (63) is fixedly inserted between adjacent stirring plates (10) on the same side. An inlet pipe (67) is fixedly inserted between the interior of the inlet chamber (61) and one of the stirring plates (10) on the same side. A return pipe (64) is fixedly inserted between the interior of the return chamber (62) and one of the stirring plates (10) on the same side. Two round pipes (65) are fixedly inserted inside the liquid pipe (9). A rotary joint (66) is installed at the bottom of the two round pipes (65). The top of one round pipe (65) extends into the interior of the inlet chamber (61), and the top of the other round pipe (65) extends into the interior of the return chamber (62).

2. The mixing device based on plastic waste recycling according to claim 1, characterized in that: A liquid-driving assembly (7) is provided at the top inner side of the mixing body (1). The liquid-driving assembly (7) includes a semi-ring frame (71) fixedly connected to the top inner side of the mixing body (1). The liquid-driving assembly (7) also includes a first piston (72) movably connected inside the mounting frame (3). A vertical shaft (73) is fixedly connected to the top centrifugal position of the first piston (72). A circular sleeve (74) is fixedly connected to the inner side of the mounting frame (3). A second piston (75) is movably connected inside the circular sleeve (74). A spring (76) is fixedly connected between the second piston (75) and the circular sleeve (74).

3. A mixing device for recycling plastic waste according to claim 2, characterized in that: The bottom of the second piston (75) is fixedly connected to a lifting shaft (77), the bottom of the lifting shaft (77) is fixedly connected to a lifting frame (78), the bottom of the lifting frame (78) extends into the interior of the liquid tube (9) and is fixedly connected to a third piston (79), the third piston (79) moves inside the liquid tube (9).

4. A mixing device for recycling plastic waste according to claim 3, characterized in that: The circular tube (65) extending into the return chamber (62) is equipped with a first check valve (710), and the return fitting (64) is equipped with a second check valve (711).

5. A mixing device for recycling plastic waste according to claim 4, characterized in that: A curved frame (712) is fixedly connected to the outside of the lifting frame (78), and the bottom of the curved frame (712) is fixedly connected to the sliding sleeve (5).

6. A mixing device for recycling plastic waste according to claim 1, characterized in that: The portion of the return pipe (64) and the inlet pipe (67) located outside the sliding sleeve (5) are made of rigid material, while the portion of the return pipe (64) and the inlet pipe (67) located inside the sliding sleeve (5) are made of flexible material.

7. A mixing device for recycling plastic waste according to claim 1, characterized in that: The rotating shaft (4) has a slot (713) near the return pipe (64) and the inlet pipe (67).

8. A mixing device for recycling plastic waste according to claim 1, characterized in that: One of the inlet pipes (67) is inserted into the bottom stirring plate (10), and the other of the inlet pipes (67) is inserted into the top stirring plate (10).

9. A mixing device for recycling plastic waste according to claim 3, characterized in that: Below the third piston (79) is a mixing assembly (8), which includes a liquid tank (81) fixedly connected to the bottom of the mixer body (1). A semiconductor cooling chip (82) is installed at the bottom of the liquid tank (81). The liquid tank (81) is connected to the rotary joint (66) through a pipeline. A rotating rod (83) is rotatably connected inside the liquid tank (81). A moving rod (84) is movably connected inside the rotating rod (83). A guide spiral groove (85) is opened on the inner side of the rotating rod (83). A guide slider (87) is fixedly connected to the outer side of the moving rod (84). The guide slider (87) moves inside the guide spiral groove (85). Below the third piston (79) is a straight rod (86). The bottom of the straight rod (86) extends from the liquid pipe (9) and is fixedly connected to the moving rod (84). A stirring plate (88) is fixedly connected to the outer side of the rotating rod (83).

10. A mixing device for recycling plastic waste according to claim 9, characterized in that: The bottom of the liquid tank (81) is made of copper.

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