Reaction device for preparing methyl methacrylate from waste plastics

Abstract

The utility model discloses a reaction device for preparing methyl methacrylate by using waste plastics, which comprises an upper end of a cracking bin, a feeding bin arranged at the upper end of the cracking bin, a working bin arranged at the front end of the feeding bin, and a screening mechanism, the screening mechanism comprises a first screening hopper, a second screening hopper, a semicircular guide rail gear, an arc-shaped rack plate and a driving shaft, semicircular guide rails are fixedly connected to the upper end and the lower end of the inner wall of the front side and the inner wall of the rear side of the feeding bin correspondingly, the first screening hopper is rotationally connected between the two semicircular guide rails on the upper side, and the second screening hopper is rotationally connected between the two semicircular guide rails on the lower side; according to the reaction device for preparing methyl methacrylate from waste plastics, pretreated waste plastic particles can be subjected to double screening, impurities in the waste plastics are effectively filtered out, and then the purity of cracked methyl methacrylate is guaranteed.

Description

Technical Field

[0001] This utility model relates to the field of methyl methacrylate preparation from waste plastics, specifically a reaction apparatus for preparing methyl methacrylate from waste plastics. Background Technology

[0002] Methyl methacrylate (MMA) is an important organic compound. Preparing MMA from waste plastics is an effective method for realizing the high-value transformation of waste plastics. Typically, a reaction device for preparing MMA from waste plastics is used to pyrolyze and transform the waste plastics.

[0003] An existing reaction device for preparing methyl methacrylate (MMA) from waste plastics uses a feed hopper to concentrate pre-treated waste plastic particles into the inside of the feed pipe. Then, a rotating spiral blade conveys the waste plastic particles. At the same time, the spiral blade and the inside of the feed hopper squeeze each other, allowing the waste plastic particles to fully absorb the heat emitted by the heating tube, thereby cracking the waste plastic into methyl methacrylate gas. The methyl methacrylate gas then enters a distillation column through the gas outlet pipe for further purification.

[0004] This reaction device for preparing methyl methacrylate (MMA) from waste plastics has some problems. The pretreated waste plastics are directly injected into the feed hopper. During the pretreatment of waste plastics, some impurities will be mixed into the waste plastic particles. After heating treatment, some other chemical reactions can be easily triggered, which can affect the purity of the methyl methacrylate gas produced by cracking. Utility Model Content

[0005] The technical problem to be solved by this utility model is to overcome the existing defects and provide a reaction device for preparing methyl methacrylate from waste plastics. The device can perform double screening on the pretreated waste plastic particles to effectively filter out the impurities inside the waste plastics, thereby ensuring the purity of the methyl methacrylate produced by cracking. This can effectively solve the problems in the background art.

[0006] To achieve the above objectives, this utility model provides the following technical solution: a reaction device for preparing methyl methacrylate from waste plastics, comprising an upper end of a pyrolysis chamber, a feeding chamber at the upper end of the pyrolysis chamber, a working chamber at the front end of the feeding chamber, and a screening mechanism.

[0007] Screening mechanism: It includes screening hopper one, screening hopper two, semi-circular guide rails, gears, arc-shaped rack plates, and drive shaft. The semi-circular guide rails are fixedly connected to the upper and lower ends of the inner walls on the front and rear sides of the feed hopper. Screening hopper one is rotatably connected between the two upper semi-circular guide rails, and screening hopper two is rotatably connected between the two lower semi-circular guide rails. Baffles are fixedly connected to the front and rear ends of the bottom walls of screening hopper one and screening hopper two. A drive shaft is rotatably connected between the working chamber and the feed hopper. A gear is fixedly connected to the rear end of the drive shaft. Arc-shaped rack plates are fixedly connected to the front end of the lower surface of screening hopper one and screening hopper two. Both arc-shaped rack plates are meshed with the gears, which can perform secondary screening of pre-treated waste plastic particles, effectively filtering out impurities inside the waste plastic, thereby ensuring the purity of the methyl methacrylate cracked out.

[0008] Furthermore, the screening mechanism also includes a drive handle and a turntable. The drive handle is fixedly connected to the front end of the drive shaft. A sliding groove is provided inside the drive handle. A rotating shaft is rotatably connected to the lower end of the inner wall of the front side of the working chamber. A turntable is fixedly connected to the rear end of the rotating shaft. A connecting shaft is fixedly connected to the rear end of the turntable. The connecting shaft is slidably connected to the sliding groove to realize the periodic shaking of the two screening buckets, and the shaking directions of the two screening buckets are opposite.

[0009] Furthermore, a controller is provided on the right side of the pyrolysis chamber. The input terminal of the controller is electrically connected to an external power source to control various electrical appliances.

[0010] Furthermore, the screening mechanism also includes a motor, which is located at the lower end of the front surface of the working chamber. The rear end of the output shaft of the motor is fixedly connected to the front end of the rotating shaft. The input end of the motor is electrically connected to the output end of the controller to provide driving force for the periodic sliding of the screening hopper.

[0011] Furthermore, a drive chamber is provided at the front end of the pyrolysis chamber, and a rotating drum is rotatably connected between the pyrolysis chamber and the drive chamber. Spiral blades are provided on the outer surface of the rotating drum, and spirally distributed kneading blocks are provided inside the pyrolysis chamber. A heating tube is provided on the inner wall of the front side of the drive chamber. The input end of the heating tube is electrically connected to the output end of the controller. While the waste plastic is being conveyed by a spiral, the spiral blades, kneading blocks, and pyrolysis chamber cooperate with each other to achieve spiral pressurization of the waste plastic. Under the heating action of the heating tube, the waste plastic is pyrolyzed to produce methyl methacrylate.

[0012] Furthermore, a driven gear is fixedly connected to the front end of the outer surface of the rotating drum, and a rotating shaft is rotatably connected to the lower end of the drive chamber. A drive gear is fixedly connected to the middle of the rotating shaft. The drive gear and the driven gear are meshed together. A second motor is provided at the lower end of the rear surface of the drive chamber. The front end of the output shaft of the second motor is fixedly connected to the rear end of the rotating shaft. The input end of the second motor is electrically connected to the output end of the controller to provide driving force for the rotation of the rotating drum.

[0013] Furthermore, a feed pipe is provided at the front end of the upper surface of the pyrolysis chamber, and the upper end of the feed pipe is fixedly connected to the lower end of the feed chamber. An exhaust pipe is provided at the rear end of the upper surface of the pyrolysis chamber, and the upper end of the exhaust pipe is connected to the air inlet of the external distillation column. An exhaust pipe is provided at the rear end of the lower surface of the pyrolysis chamber. Evenly distributed support legs are fixedly connected to the lower end of the pyrolysis chamber. Mounting holes are provided at both the front and rear ends of the lower surface of the support legs to provide channels for the inlet and outlet of waste plastics and the exhaust of gas.

[0014] Compared with the prior art, the beneficial effects of this utility model are as follows: This reaction apparatus for preparing methyl methacrylate from waste plastics has the following advantages:

[0015] The motor drives the turntable to rotate, and while the connecting shaft slides inside the chute, it periodically moves the drive handle laterally. This, in turn, through the gear mechanism, causes the first and second screening hoppers to oscillate laterally and periodically. The screening directions of the first and second screening hoppers are opposite, thus achieving double screening of the pre-treated waste plastic particles. This effectively filters out impurities inside the waste plastic, avoids triggering other chemical reactions and generating other gases, and ensures the purity of the methyl methacrylate produced by cracking. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] Figure 2 This is a cross-sectional view of the internal structure of this utility model;

[0018] Figure 3 This is a cross-sectional view of the pyrolysis chamber of this utility model;

[0019] Figure 4 This is an enlarged structural diagram of point A in this utility model.

[0020] In the diagram: 1. Cracking chamber, 2. Drive chamber, 3. Feed chamber, 4. Working chamber, 5. Screening mechanism, 51. Screening hopper one, 52. Screening hopper two, 53. Semi-circular guide rail, 54. Gear, 55. Arc-shaped rack plate, 56. Drive shaft, 57. Drive handle, 58. Turntable, 59. Motor one, 6. Rotary drum, 7. Spiral blade, 8. Kneading block, 9. Heating tube, 10. Driven gear, 11. Rotary shaft, 12. Motor two, 13. Discharge pipe, 14. Feed pipe, 15. Air outlet pipe, 16. Controller, 17. Support leg. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] Please see Figure 1-4 This embodiment provides a technical solution: a reaction device for preparing methyl methacrylate using waste plastics, including the upper end of a pyrolysis chamber 1, a feeding chamber 3 provided at the upper end of the pyrolysis chamber 1, a working chamber 4 provided at the front end of the feeding chamber 3, a controller 16 provided on the right side of the pyrolysis chamber 1, the input end of the controller 16 being electrically connected to an external power supply, and also including a screening mechanism 5.

[0023] Screening mechanism 5 includes screening hopper 1 51, screening hopper 2 52, semi-circular guide rails 53, gears 54, arc-shaped rack plates 55, and drive shaft 56. The semi-circular guide rails 53 are fixedly connected to the upper and lower ends of the inner walls of the front and rear sides of the feed hopper 3, respectively. Screening hopper 1 51 is rotatably connected between the two upper semi-circular guide rails 53, and screening hopper 2 52 is rotatably connected between the two lower semi-circular guide rails 53. The central axes of the two semi-circular guide rails 53, screening hopper 1 51, and screening hopper 2 52 coincide. Baffles are fixedly connected to the front and rear ends of the bottom walls of screening hopper 1 51 and screening hopper 2 52. Drive shaft 56 is rotatably connected between the working chamber 4 and the feed hopper 3. Gear 54 is fixedly connected to the rear end of drive shaft 56. The front ends of the lower surfaces of screening hopper 1 51 and screening hopper 2 52 are fixed. The screening mechanism 5 includes two arc-shaped rack plates 55, both of which mesh with gears 54. The screening mechanism 5 also includes a drive handle 57 and a turntable 58. The drive handle 57 is fixedly connected to the front end of a drive shaft 56, and a groove is provided inside the drive handle 57. A rotating shaft is rotatably connected to the lower end of the front inner wall of the working chamber 4. The rear end of the rotating shaft is fixedly connected to the turntable 58, and the rear end of the turntable 58 is fixedly connected to a connecting shaft, which is slidably connected to the groove. The screening mechanism 5 also includes a motor 59, which is located at the lower end of the front surface of the working chamber 4. The rear end of the output shaft of the motor 59 is fixedly connected to the front end of the rotating shaft. The input end of the motor 59 is electrically connected to the output end of the controller 16. Pre-treated waste plastic particles are injected into the feed hopper 3 for pre-treatment. The waste plastic particles fall into screening hopper 52. Controller 16 activates motor 59. The output shaft of motor 59 rotates, driving the rotating shaft, which in turn drives turntable 58. Turntable 58 rotates, driving the connecting shaft. The connecting shaft slides inside the chute. Simultaneously, when the connecting shaft rotates to the left with turntable 58, it moves drive handle 57 to the left; when it rotates to the right with turntable 58, it moves drive handle 57 to the right. As the connecting shaft follows turntable 58 in circular motion, drive handle 57 oscillates laterally periodically. When drive handle 57 rotates to the left, drive shaft 56 rotates to the left, causing gear 54 to rotate clockwise. The clockwise rotation of gear 54 acts on two arc-shaped rack plates 5... 5. This causes the upper arc-shaped rack plate 55 to rotate to the right and the lower arc-shaped rack plate 55 to rotate to the left. The right rotation of the upper arc-shaped rack plate 55 drives the second screening hopper 52 to rotate to the right, and the left rotation of the lower arc-shaped rack plate 55 drives the first screening hopper 51 to rotate to the left. When the drive handle 57 rotates to the right, the drive shaft 56 follows the drive handle 57 to rotate to the right, which in turn causes the gear 54 to rotate counterclockwise. The counterclockwise rotation of the gear 54 acts on the two arc-shaped rack plates 55, causing the upper arc-shaped rack plate 55 to rotate to the left and the lower arc-shaped rack plate 55 to rotate to the right. The left rotation of the upper arc-shaped rack plate 55 drives the second screening hopper 52 to rotate to the left, and the right rotation of the lower arc-shaped rack plate 55 drives the first screening hopper 51 to rotate to the right. This is accompanied by the horizontal periodic oscillation of the drive handle 57.Screening hopper 51 and screening hopper 52 slide laterally and periodically under the guidance of corresponding semi-circular guide rails 53, thereby achieving secondary screening of the pre-treated waste plastic particles and effectively filtering out impurities inside the pre-treated waste plastic particles;

[0024] The pyrolysis chamber 1 has a drive chamber 2 at its front end, and a rotating drum 6 is rotatably connected between the pyrolysis chamber 1 and the drive chamber 2. The outer surface of the rotating drum 6 is provided with spiral blades 7. The pitch of the spiral blades 7 is the same at both ends, and the pitch in the middle of the spiral blades 7 is smaller than the pitch at both ends. Inside the pyrolysis chamber 1, there are spirally distributed kneading blocks 8. The pitch of the kneading blocks 8 is the same as the pitch of the corresponding spiral blades 7. A heating tube 9 is provided on the front inner wall of the drive chamber 2. The input end of the heating tube 9 is electrically connected to the output end of the controller 16. A driven gear 10 is fixedly connected to the front end of the outer surface of the rotating drum 6. A rotating shaft 11 is rotatably connected to the lower end of the drive chamber 2. A drive gear is fixedly connected to the middle of the rotating shaft 11. The drive gear and the driven gear 10 are meshed. A second motor 12 is provided at the lower end of the rear surface of the drive chamber 2. The front end of the output shaft of the second motor 12 is fixedly connected to the rear end of the rotating shaft 11. The input end of the second motor 12 is electrically connected to the output end of the controller 16. The controller 16 activates the heating tube 9, which heats the air inside the pyrolysis chamber 1. The air conducts heat to the waste plastic particles, causing them to undergo a pyrolysis reaction and generate methyl methacrylate gas. Simultaneously, the controller 16 activates the second motor 12. The output shaft of the second motor 12 rotates, driving the rotating shaft 11 to rotate. The rotating shaft 11 then drives the drive gear, which in turn drives the driven gear. The driven gear drives the rotating drum 6, which in turn drives the spiral blade 7. The spiral blade 7 conveys the waste plastic particles in a spiral motion. At the same time, the spiral blade 7, the kneading block 8, and the inner wall of the pyrolysis chamber 1 support each other, compressing the waste plastic particles. This allows the waste plastic particles to efficiently absorb heat and accelerate pyrolysis. Because the pitch in the middle of the spiral blade 7 is smaller than the pitch at the front and rear ends of the spiral blade 7, the movement required for the waste plastic particles to reach the middle of the pyrolysis chamber 1 is reduced, allowing the pyrolysis reaction of the waste plastic particles to be more complete.

[0025] The pyrolysis chamber 1 has a feed pipe 14 at the front end of its upper surface. Filtered waste plastic particles enter the interior of the pyrolysis chamber 1 through the feed pipe 14. The upper end of the feed pipe 14 is fixedly connected to the lower end of the feed chamber 3. The pyrolysis chamber 1 has an exhaust pipe 15 at the rear end of its upper surface. The upper end of the exhaust pipe 15 is connected to the air inlet of the external distillation column. Methyl methacrylate gas is then discharged through the exhaust pipe 15. Under the action of the external distillation column, the methyl methacrylate gas condenses into liquid and is then stored. The pyrolysis chamber 1 has an exhaust pipe 13 at the rear end of its lower surface. The pyrolysis chamber 1 has uniformly distributed support legs 17 fixedly connected to its lower end. The support legs 17 have mounting holes at both the front and rear ends of their lower surfaces.

[0026] The working principle of the reaction device for preparing methyl methacrylate from waste plastics provided by this utility model is as follows: During operation, personnel use bolts to stably connect the mounting holes at the lower end of the support leg 17 to the threaded holes in the working area, thereby achieving stable installation of the pyrolysis chamber 1, the drive chamber 2, and other mechanisms. After stable installation, personnel inject pre-treated waste plastic particles into the feed chamber 3. The pre-treated waste plastic particles fall into the screening hopper 2 52. Personnel use the controller 16 to operate the motor 59. The output shaft of the motor 59 rotates, driving the rotating shaft to rotate, which in turn drives the turntable 58 to rotate. The rotation of the turntable 58 drives the connecting shaft to rotate. The connecting shaft slides inside the chute. At the same time, when the connecting shaft rotates to the left with the turntable 58, the connecting shaft moves the drive handle 5 to the left. 7. When the connecting shaft rotates to the right with the turntable 58, the connecting shaft moves the drive handle 57 to the right. As the connecting shaft moves in a circular motion with the turntable 58, the drive handle 57 oscillates laterally periodically. When the drive handle 57 rotates to the left, the drive shaft 56 rotates to the left with the drive handle 57, causing the gear 54 to rotate clockwise. The clockwise rotation of the gear 54 acts on the two arc-shaped rack plates 55, causing the upper arc-shaped rack plate 55 to rotate to the right and the lower arc-shaped rack plate 55 to rotate to the left. The right rotation of the upper arc-shaped rack plate 55 drives the second screening hopper 52 to rotate to the right, and the left rotation of the lower arc-shaped rack plate 55 drives the first screening hopper 51 to rotate to the left. When the drive handle 57 rotates to the right, the drive shaft 56 rotates to the right with the drive handle 57, thereby causing... Gear 54 rotates counterclockwise, which in turn affects two arc-shaped rack plates 55, causing the upper arc-shaped rack plate 55 to rotate to the left and the lower arc-shaped rack plate 55 to rotate to the right. The leftward rotation of the upper arc-shaped rack plate 55 drives the second screening hopper 52 to rotate to the left, and the rightward rotation of the lower arc-shaped rack plate 55 drives the first screening hopper 51 to rotate to the right. As the drive handle 57 performs lateral periodic oscillation, the first screening hopper 51 and the second screening hopper 52 slide laterally periodically under the guidance of the corresponding semi-circular guide rails 53, thereby achieving secondary screening of the pre-treated waste plastic particles and effectively filtering out impurities inside the pre-treated waste plastic particles. The filtered waste plastic particles enter the interior of the pyrolysis chamber 1 through the feed pipe 14, and then the controller 16 heats them. When pipe 9 operates, heating pipe 9 heats the air inside the pyrolysis chamber 1. The air conducts heat to the waste plastic particles, causing them to undergo a pyrolysis reaction and generate methyl methacrylate gas. The methyl methacrylate gas is then discharged through outlet pipe 15 and condensed into liquid under the action of an external distillation column for storage. Simultaneously, controller 16 activates motor 12. The output shaft of motor 12 rotates, driving shaft 11 to rotate. Shaft 11 rotates, driving drive gear to rotate, which in turn drives driven gear. Driven gear rotates, driving drum 6 to rotate, which in turn drives spiral blade 7 to rotate. Spiral blade 7 performs spiral conveying of waste plastic particles. Spiral blade 7, kneading block 8, and inner wall of pyrolysis chamber 1 support each other.The compression of waste plastic particles allows them to efficiently absorb heat and accelerate pyrolysis. Because the pitch of the central part of the spiral blade 7 is smaller than the pitch at both ends, the movement required for the waste plastic particles to reach the center of the pyrolysis chamber 1 is reduced, allowing the pyrolysis reaction to be more complete.

[0027] It is worth noting that the controller 16 disclosed in the above embodiments controls the operation of motor 59, heating tube 9 and motor 12 using methods commonly used in the prior art.

[0028] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A reaction apparatus for preparing methyl methacrylate from waste plastics, comprising an upper end of a pyrolysis chamber (1), a feed chamber (3) provided at the upper end of the pyrolysis chamber (1), and a working chamber (4) provided at the front end of the feed chamber (3), characterized in that: It also includes a screening mechanism (5); Screening mechanism (5): It includes screening hopper one (51), screening hopper two (52), semi-circular guide rail (53), gear (54), arc-shaped rack plate (55) and drive shaft (56). The semi-circular guide rail (53) is fixedly connected to the upper and lower ends of the inner walls of the front and rear sides of the feed hopper (3). Screening hopper one (51) is rotatably connected between the two upper semi-circular guide rails (53), and screening hopper two is rotatably connected between the two lower semi-circular guide rails (53). (52) Baffles are fixedly connected to the front and rear ends of the bottom walls of screening hopper one (51) and screening hopper two (52). A drive shaft (56) is rotatably connected between the working chamber (4) and the feeding chamber (3). A gear (54) is fixedly connected to the rear end of the drive shaft (56). An arc-shaped rack plate (55) is fixedly connected to the front end of the lower surface of screening hopper one (51) and screening hopper two (52). Both arc-shaped rack plates (55) are meshed with the gear (54).

2. The reaction device for preparing methyl methacrylate from waste plastics according to claim 1, characterized in that: The screening mechanism (5) also includes a drive handle (57) and a turntable (58). The drive handle (57) is fixedly connected to the front end of the drive shaft (56). A sliding groove is provided inside the drive handle (57). A rotating shaft is rotatably connected to the lower end of the front inner wall of the working chamber (4). The rear end of the rotating shaft is fixedly connected to the turntable (58). The rear end of the turntable (58) is fixedly connected to a connecting shaft. The connecting shaft is slidably connected to the sliding groove.

3. The reaction device for preparing methyl methacrylate from waste plastics according to claim 2, characterized in that: A controller (16) is provided on the right side of the pyrolysis chamber (1), and the input terminal of the controller (16) is electrically connected to an external power supply.

4. The reaction device for preparing methyl methacrylate from waste plastics according to claim 3, characterized in that: The screening mechanism (5) also includes a motor (59), which is located at the lower end of the front surface of the working chamber (4). The rear end of the output shaft of the motor (59) is fixedly connected to the front end of the rotating shaft, and the input end of the motor (59) is electrically connected to the output end of the controller (16).

5. The reaction device for preparing methyl methacrylate using waste plastics according to claim 3, characterized in that: The front end of the pyrolysis chamber (1) is provided with a drive chamber (2), and a rotating drum (6) is rotatably connected between the pyrolysis chamber (1) and the drive chamber (2). The outer surface of the rotating drum (6) is provided with a spiral blade (7), and the interior of the pyrolysis chamber (1) is provided with a spirally distributed kneading block (8). The front inner wall of the drive chamber (2) is provided with a heating tube (9), and the input end of the heating tube (9) is electrically connected to the output end of the controller (16).

6. The reaction device for preparing methyl methacrylate from waste plastics according to claim 5, characterized in that: A driven gear (10) is fixedly connected to the front end of the outer surface of the rotating drum (6). A rotating shaft (11) is rotatably connected to the lower end of the drive chamber (2). A drive gear is fixedly connected to the middle of the rotating shaft (11). The drive gear and the driven gear (10) are meshed together. A second motor (12) is provided at the lower end of the rear surface of the drive chamber (2). The front end of the output shaft of the second motor (12) is fixedly connected to the rear end of the rotating shaft (11). The input end of the second motor (12) is electrically connected to the output end of the controller (16).

7. The reaction device for preparing methyl methacrylate using waste plastics according to claim 1, characterized in that: A feed pipe (14) is provided at the front end of the upper surface of the pyrolysis chamber (1). The upper end of the feed pipe (14) is fixedly connected to the lower end of the feed chamber (3). An exhaust pipe (15) is provided at the rear end of the upper surface of the pyrolysis chamber (1). The upper end of the exhaust pipe (15) is connected to the air inlet of the external distillation column. An exhaust pipe (13) is provided at the rear end of the lower surface of the pyrolysis chamber (1). Evenly distributed support legs (17) are fixedly connected to the lower end of the pyrolysis chamber (1). Mounting holes are provided at both the front and rear ends of the lower surface of the support legs (17).

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