Plastic waste catalytic depolymerization and recycling equipment

Abstract

The present application relates to the technical field of plastic waste recycling, and discloses a plastic waste catalytic depolymerization and recycling equipment, which comprises a rack, a feeding hopper is arranged on the rack, a pretreatment device is connected to the outlet of the feeding hopper, the pretreatment device comprises a crushing cavity and multiple groups of roller type crushing assemblies arranged in the crushing cavity, a spiral conveying mechanism is arranged at the bottom of the pretreatment device, the spiral conveying mechanism is connected to a catalytic depolymerization reaction kettle, a catalyst quantitative adding device and a pressure regulating valve are connected to the top of the catalytic depolymerization reaction kettle, a slag outlet and a gas-liquid separation device are arranged at the bottom of the catalytic depolymerization reaction kettle, and the top of the gas-liquid separation device is connected to a condensation recovery system through a first gas guide pipe. The present application realizes continuous and efficient operation from crushing pretreatment, catalytic depolymerization to gas-liquid condensation and oil-water separation, and improves the resource utilization efficiency of waste plastics and the quality of oil products.

Description

Technical Field

[0001] This invention relates to the field of plastic waste recycling technology, specifically to a device for catalytic depolymerization and recycling of plastic waste. Background Technology

[0002] Against the backdrop of increasingly severe global plastic pollution and an urgent need for resource recycling, the effective disposal of waste plastics has become a focal point of concern for both industry and environmental protection. Traditional methods of waste plastic treatment mainly include landfill and incineration. However, landfill not only occupies a large amount of land resources, but also causes persistent soil and groundwater pollution due to the extremely long degradation cycle of plastics in the natural environment. Incineration, while achieving volume reduction, can easily produce highly toxic substances and harmful gases such as dioxins if the combustion temperature is not properly controlled or the exhaust gas treatment facilities are inadequate, resulting in serious air pollution. To achieve resource utilization of waste plastics at its source, chemical catalytic depolymerization technology has emerged. This technology aims to break down long polymer chains and convert them into high-value-added liquid oils or chemical raw materials through high-temperature pyrolysis combined with the action of a catalyst.

[0003] However, existing plastic depolymerization equipment still suffers from many drawbacks in practical industrial applications. For example, pretreatment systems are often incompatible with complex mixed waste plastics, resulting in low crushing efficiency and severe equipment wear. Uneven heat and mass transfer inside the reactor easily leads to localized overheating and coking, which not only significantly reduces oil production but also seriously affects the stability of continuous operation. Existing recycling equipment lacks a refined removal mechanism for impurities in the pyrolysis products, often resulting in poor oil quality and incomplete gas-liquid separation, causing frequent blockages in the condensation system and high maintenance costs. Furthermore, existing systems mostly rely on manual control or simple instrument monitoring, lacking intelligent closed-loop scheduling of the entire reaction process, leading to poor production safety, serious energy waste, and difficulty in achieving large-scale continuous and standardized industrial production. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a catalytic depolymerization and recycling device for plastic waste, which can improve the resource utilization efficiency and oil quality of waste plastics.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a catalytic depolymerization and recycling device for plastic waste, comprising: a frame, a feeding hopper on the frame, a pretreatment device connected to the outlet of the feeding hopper, the pretreatment device including a crushing chamber and multiple sets of roller crushing components disposed within the crushing chamber, a spiral conveying mechanism at the bottom of the pretreatment device connected to a catalytic depolymerization reactor, a rotating stirring shaft inside the catalytic depolymerization reactor, multiple layers of inclined stirring blades integrated on the rotating stirring shaft, an electromagnetic induction heating jacket fitted on the outer side of the catalytic depolymerization reactor, a catalyst metering device and a pressure regulating valve connected to the top of the catalytic depolymerization reactor, a temperature monitoring sensor and a pressure sensor on the side wall of the catalytic depolymerization reactor, a slag outlet at the bottom of the catalytic depolymerization reactor and a gas-liquid separation device connected to its side, and the top of the gas-liquid separation device being connected to... The first gas guide pipe is connected to the condensation recovery system, which includes multiple condenser pipes connected in series and a circulating cooling water chamber located outside the condenser pipes. An oil-water separator is connected to the end of the condensation recovery system, and the oil-water separator has an oil phase output pipe and a water phase output pipe. A residue collection box is located at the bottom of the gas-liquid separation device. A central controller is also integrated on the frame, and the central controller is signal-connected to the pretreatment device, the catalytic depolymerization reactor, and the condensation recovery system. A liquid level sensor is installed inside the catalytic depolymerization reactor. A shock-absorbing base is located at the bottom of the frame. The inner wall of the crushing chamber is coated with a wear-resistant ceramic coating. The rotating stirring shaft is driven by a servo motor. The electromagnetic induction heating jacket is wrapped with a rock wool insulation layer. A sealing gas lock valve is installed at the slag outlet. A filter screen is installed on the first gas guide pipe. A flame arrester is installed at the air inlet of the condensation recovery system. The central controller integrates a touch screen display.

[0006] Preferably, the crushing chamber of the pretreatment device is provided with a cleanup mechanism, which includes a magnetic separation roller disposed above the roller crushing assembly and a vibrating screen disposed on the side wall of the crushing chamber.

[0007] Preferably, the inner wall of the catalytic depolymerization reactor is provided with a guide plate, which is staggered with the stirring blades on the rotating stirring shaft to increase the turbulence intensity of the plastic material in the catalytic depolymerization reactor.

[0008] Preferably, the catalyst metering device includes a storage tank equipped with a weighing sensor and a variable frequency screw feeder connected to the bottom of the storage tank.

[0009] Preferably, the circulating cooling water chamber of the condensation recovery system is connected to an external cooling tower and a cooling circulation pump, and the central controller automatically adjusts the flow rate of the cooling circulation pump according to the temperature at the outlet of the circulating cooling water chamber.

[0010] Preferably, the gas-liquid separation device is provided with a cyclone separator inner cylinder, which has an inverted conical structure and is used to initially separate the pyrolysis gas from the liquid residue by centrifugal force.

[0011] Preferably, the oil-water separator is equipped with an automatic liquid level detector, and the oil phase output pipe and the water phase output pipe are respectively equipped with electromagnetic proportional valves.

[0012] Preferably, the frame is provided with an exhaust gas treatment unit, which is connected to the end of the condensation recovery system through a second gas guide pipe, and is used to perform activated carbon adsorption and catalytic oxidation treatment on the condensed non-condensable gas.

[0013] Preferably, the bottom of the catalytic depolymerization reactor is provided with a heating belt, which is used to maintain the temperature of the slag outlet area and prevent the liquid residue from condensing and clogging during the slag discharge process.

[0014] Preferably, the central controller has a built-in heating control program based on the PID algorithm, which adjusts the power of the electromagnetic induction heating jacket in real time according to the feedback data of the temperature monitoring sensor, so as to keep the temperature inside the reactor stable within the range of 350°C to 450°C.

[0015] Compared with the prior art, the present invention has the following beneficial effects: This type of plastic waste catalytic depolymerization and recycling equipment, through integrated full-process automation design, realizes continuous and efficient operation from crushing and pretreatment, catalytic depolymerization to gas-liquid condensation and oil-water separation, thereby improving the resource utilization efficiency of waste plastics and the quality of oil produced. By incorporating a wear-resistant coating pretreatment component and an intelligent magnetic separation and impurity removal mechanism, the problems of difficult feeding of complex waste materials and rapid equipment wear are effectively solved. The synergistic effect of electromagnetic induction heating, multi-layered spiral stirring blades, and guide plates ensures uniform heating of materials within the reactor, completely preventing coking and significantly improving the catalytic reaction rate and thermal energy utilization. The introduction of a cyclone separator inner cylinder, a multi-stage series condensation system, and automatic liquid level detection technology not only achieves deep separation of pyrolysis oil and gas from solid residues but also ensures high-purity output and automatic diversion of oil and water products. Simultaneously, the central controller's intelligent closed-loop control logic based on PID algorithms endows the system with extremely high safety stability and operational accuracy, effectively reducing energy consumption and minimizing manual intervention. This allows the equipment to meet stringent environmental emission standards while possessing excellent industrial continuous production capabilities and long-term operational reliability. Attached Figure Description

[0016] Figure 1 This is a three-dimensional structural diagram of the entire invention; Figure 2 This is a three-dimensional structural diagram of the entire invention from another angle; Figure 3 This is a front view of the entire invention; Figure 4 This is a side view of the entire invention; Figure 5 This is a cross-sectional three-dimensional structural diagram of the entire invention; Figure 6 This is a cross-sectional three-dimensional structural diagram of the overall catalytic depolymerization reactor of the present invention; Figure 7 This is a cross-sectional three-dimensional structural diagram of the overall circulating cooling water chamber of the present invention; Figure 8 This is a cross-sectional three-dimensional structural diagram of the overall gas-liquid separation device of the present invention.

[0017] In the diagram: 1. Frame; 2. Feed hopper; 3. Pretreatment device; 4. Crushing chamber; 5. Roller crushing assembly; 6. Screw conveyor mechanism; 7. Catalytic depolymerization reactor; 8. Rotary stirring shaft; 9. Stirring blades; 10. Electromagnetic induction heating jacket; 11. Catalyst quantitative addition device; 12. Pressure regulating valve; 13. Temperature monitoring sensor; 14. Pressure sensor; 15. Slag outlet; 16. Gas-liquid separation device; 17. First gas guide pipe; 18. Condensation recovery system; 19. Condensation pipe; 20. Circulating cooling water chamber; 21. Oil-water separator; 22. Oil phase output pipe; 23. Water phase output pipe; 24. 101. Residue collection box; 25. Central controller; 26. Liquid level sensor; 27. Shock-absorbing base; 28. Wear-resistant ceramic coating; 29. ​​Servo motor; 30. Rock wool insulation layer; 31. Sealing airlock valve; 32. Filter screen; 33. Flame arrester; 34. Touch screen display; 101. Magnetic separator roller; 102. Vibrating screen; 201. Guide plate; 301. Storage tank; 302. Variable frequency screw feeder; 401. External cooling tower; 402. Cooling circulation pump; 501. Cyclone separator inner cylinder; 601. Electromagnetic proportional valve; 701. Exhaust gas treatment unit; 702. Second air guide pipe; 801. Heating belt. Detailed Implementation

[0018] The technical solutions 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.

[0019] Please see Figures 1 to 8 A device for catalytic depolymerization and recycling of plastic waste.

[0020] The entire equipment is supported by a frame 1 welded from high-strength steel. Considering the high-frequency mechanical impact of the crushing mechanism and the torque fluctuations generated by the rotation of the large stirring mechanism during operation of the plastic pyrolysis equipment, the frame 1 is designed as a split welded structure to enhance its resistance to eccentric loads. The bottom of the frame 1 is equipped with four shock-absorbing bases 27. The core component of each shock-absorbing base 27 is a multi-layer composite damping rubber pad with a built-in hydraulic buffer unit, capable of attenuating structural noise and physical vibration in the frequency range of 10Hz to 200Hz to an environmentally acceptable level. This base design not only protects the measurement accuracy of precision sensors, such as the temperature monitoring sensor 13 and the pressure sensor 14, but also improves the fatigue life of the equipment, ensuring that the entire machine will not experience structural resonance under long-term full-load operation.

[0021] Plastic waste comes from diverse sources, containing hard impurities such as metal, wood chips, and sand. If it enters the reactor directly, it will not only wear down the rotating stirring shaft 8 and the reactor body, but may also cause catalyst poisoning or pipeline blockage.

[0022] The feed hopper 2 employs an internal electrolytic polishing process, achieving an inner surface roughness Ra≤0.4μm. This significantly reduces the coefficient of friction for waste plastics, especially flexible film materials, preventing material buildup. The feed hopper 2 is tilted at 65°, utilizing gravity guidance to ensure smooth feeding.

[0023] Multi-stage crushing, with the crushing chamber 4 within the pretreatment device 3 being one of the key technical means of this invention. The wear-resistant ceramic coating 28 covering the inner wall of the crushing chamber 4 is achieved through plasma spraying. This coating uses alumina and zirconium oxide as the matrix, with the addition of trace amounts of toughening additives, achieving a Vickers hardness of HV1500 or higher. The multiple sets of double-roll crushing components 5 inside are made of high-chromium alloy material, and the shape of the blades is designed through computer fluid dynamics simulation, presenting a spiral arrangement. This design not only generates extremely high shearing force but also forces the plastic fragments downward, improving crushing efficiency.

[0024] For efficient impurity removal, a suspended magnetic separator 101 above the crushing assembly uses a high-strength neodymium iron boron magnet array to remove iron contaminants from the material with an efficiency of over 98%. Following this, a vibrating screen 102 uses a variable-frequency eccentric vibration mechanism to classify the material. Dust particles smaller than 5mm are directly screened out, while excessively large materials are forcibly retained and passed through the rollers again, ensuring that the diameter of the plastic particles entering subsequent processes is precisely controlled between 15mm and 25mm, laying a good material foundation for subsequent high-temperature uniform deagglomeration.

[0025] The catalytic depolymerization reactor 7 is the core reaction center of this invention, and its internal space layout is extremely sophisticated.

[0026] For heating and insulation, the electromagnetic induction heating jacket 10 directly generates heat on the vessel wall through a high-frequency alternating magnetic field, achieving a thermal efficiency of over 95%. Compared to traditional heat transfer oil heating, electromagnetic heating can achieve a millisecond-level response speed. To maximize energy utilization, the vessel body is wrapped with a 100mm thick high-quality aluminum silicate rock wool insulation layer 30 and encapsulated with a stainless steel shell, ensuring that the shell temperature is only slightly higher than room temperature at a high temperature of 450℃ in the core reaction zone inside the vessel, thereby significantly reducing heat loss.

[0027] As a key safety and process control component at the top of the catalytic depolymerization reactor 7, the pressure regulating valve 12 plays a crucial role in dynamically balancing the reaction pressure within the reactor. During pyrolysis, the material decomposes to produce a large amount of gaseous products. This valve ensures that the reactor remains within a preset slightly positive pressure range, maintaining the kinetic stability of the pyrolysis reaction, preventing changes in product composition due to pressure fluctuations, and acting as the first safety unloading barrier when the system pressure abnormally rises, preventing overpressure risks. Simultaneously, this valve also isolates the reactor from external air, ensuring an inert atmosphere environment and preventing oxidation reactions or deflagration hazards at high temperatures. The power stirring system features a rotating stirring shaft 8 driven by a high-torque servo motor 29, enabling smooth start-up and stepless speed regulation. The stirring blades 9 are designed with a segmented helical arrangement, with each layer of blades having a different angle. This design simulates a compression and propulsion effect, overcoming the resistance of high-viscosity molten plastic. The guide plate 201 is welded to the inner wall of the reactor, serving not only as a flow turbulence agent but, more importantly, generating strong centrifugal and axial mixing effects. This thoroughly disrupts the laminar flow zone generated by the molten plastic, achieving a uniform distribution of reactants and catalyst at the microscopic level, significantly improving the oil yield and quality of catalytic depolymerization.

[0028] Precise catalysis and feeding: The catalyst metering device 11 employs loss-in-weight weighing technology, and the variable frequency screw feeder 302 connected to the bottom of the storage tank 301 can achieve continuous pulsed addition of trace amounts of catalyst. The central controller 25 dynamically adjusts the catalyst addition ratio through a PID feedback loop based on the reaction pressure and the real-time amount of oil and gas generated.

[0029] The mixture produced by catalytic depolymerization contains, in addition to the oil and gas that need to be collected, a large amount of solid coke, catalyst waste and a small amount of non-condensable gas.

[0030] The core of the cyclone separator, the gas-liquid separator 16, is the cyclone separator inner cylinder 501. After the pyrolysis mixture enters the separator, it enters tangentially. Using centrifugal force, the denser solid residue is thrown against the cylinder wall and slides down to the residue collection box 24 at the bottom. The gaseous substance, located at the center where centrifugal force is less, is led out through the upper first gas guide pipe 17. A filter screen 32 is installed on the first gas guide pipe 17, acting as a physical barrier in the gas path from the catalytic depolymerization reactor 7 to the condensation recovery system 18. Its main function is to intercept fine solid particles, catalyst dust, and carbon black impurities carried by the pyrolysis gas. Through primary purification of the gas flow, the filter screen 32 effectively prevents these solid impurities from entering the subsequent precision multi-stage condenser tubes 19, avoiding impurities from depositing and scaling on the inner wall of the condenser, thus reducing heat exchange efficiency or blocking the condensation channels. This significantly reduces the maintenance frequency of the condensation recovery system 18, extends the overall service life of the equipment, and improves the purity of the recovered oil and gas.

[0031] The slag discharge is sealed, and the sealing airlock valve 31 at the slag discharge port 15 adopts a metal hard seal structure, which can maintain airtightness at high temperatures and prevent outside air from entering the vessel. In addition, the heating belt 801 continuously maintains the temperature of the slag discharge port 15 above 200°C to prevent the heavy oil in the residue from cooling and sticking together, which could cause the slag discharge mechanism to jam.

[0032] The multi-stage condensation and condensation recovery system 18 is equipped with three-stage series condenser pipes 19. The first stage is forced air condensation for initial cooling; the second and third stages are circulating cooling water chambers 20, which use circulating water provided by an external cooling tower 401 for precise temperature control. The central controller 25 monitors the temperature difference between the inlet and outlet of the circulating cooling water chamber 20 and adjusts the frequency conversion drive signal of the cooling circulation pump 402 in real time to ensure that the condensation temperature is strictly controlled, thereby ensuring the consistency of the condensed oil composition.

[0033] For flame arrest and safety, a flame arrester 33 is installed at the air inlet of the condensation system. The inside is filled with a high-density stainless steel sintered filter element. This filter element has a large heat dissipation surface area. In the event of abnormal backfire, the flame will be extinguished instantly by the heat absorbed by the filter element, effectively preventing explosive gases from entering the reactor.

[0034] Oil-water separation is achieved through an advanced dual mechanism of gravity settling and electrostatic demulsification in oil-water separator 21. An automatic liquid level interface detector, utilizing a dielectric constant probe, accurately identifies the interface between oil and water. When the oil layer accumulates to a set height, the electromagnetic proportional valve 601 automatically activates, discharging the oil and water phases into their respective storage tanks 301. The entire process is fully automated, requiring no manual monitoring. The oil phase output pipe 22 is a dedicated downstream discharge channel for oil from oil-water separator 21, its main function being to efficiently output the fuel oil fraction obtained after treatment by the condensation recovery system 18. This pipeline works in conjunction with an automatic liquid level detector and an electromagnetic proportional valve 601. When the system detects that the oil layer has reached the predetermined interface, the oil phase output pipe 22 automatically opens to perform precise oil-water separation and discharge, ensuring the purity of the output oil and preventing water from entering the storage tank. This ensures that the recovered plastic pyrolysis oil meets industrial fuel standards or the requirements for raw materials for further processing. The water phase output pipe 23 is responsible for discharging the separated process wastewater from the oil-water separator 21. Its main function is to maintain the phase balance inside the oil-water separator 21. Since a small amount of water or condensate from the reaction may accompany the plastic pyrolysis process, this water will mix with the oil. Under the coordinated control of the electromagnetic proportional valve 601, the water phase output pipe 23 can promptly discharge the water phase deposited at the bottom based on the oil-water interface detection results, effectively preventing overflow or oil-water emulsification caused by water accumulation. This ensures the quality of the oil produced by the entire recovery system and meets the process requirements for centralized wastewater treatment in environmental protection emissions.

[0035] The soul of the entire device lies in the multi-dimensional control strategy integrated into the central controller 25.

[0036] The intelligent temperature control algorithm, with its built-in PID heating control program, not only considers temperature but also incorporates a differential term, enabling it to predict sudden temperature changes. For example, when the feed rate suddenly increases, the program will increase the heating power in advance to prevent localized overcooling of the reactor. The operating temperature is locked between 350℃ and 450℃, a range proven to be the optimal process window for achieving the highest yield of plastic pyrolysis oils and the lowest carbon buildup.

[0037] The environmentally friendly exhaust gas treatment unit 701 is the guarantee for the equipment to achieve green production. The small amount of non-condensable gas remaining after condensation is introduced into the exhaust gas unit through the second gas guide pipe 702. It first passes through the activated carbon adsorption tower to remove organic vapors, and then enters the catalytic oxidation chamber for deep combustion. The final emission gas meets the environmental emission standards, achieving truly pollution-free treatment.

[0038] The touchscreen human-machine interface is not only a parameter display terminal, but also integrates a fault tree logic analysis system. Once the equipment alarms, the screen will display fault location suggestions and emergency operation guidelines in real time, greatly reducing the difficulty of maintenance.

[0039] The plastic waste catalytic depolymerization and recycling equipment of the present invention is based on a thermochemical depolymerization and continuous conveying circulation process. First, coarsely crushed plastic waste is introduced through the feed hopper 2. Multiple sets of roller crushing components 5, assisted by a magnetic separator roller 101 and a vibrating screen 102, process the plastic into uniform particles. These particles are then conveyed by a screw conveyor 6 into a catalytic depolymerization reactor 7. Inside the reactor, precise temperature control provided by an electromagnetic induction heating jacket 10, along with a high-intensity turbulent field created by a rotating stirring shaft 8, stirring blades 9, and guide plates 201, causes the plastic to undergo efficient depolymerization under the action of a catalyst, breaking down long-chain macromolecules into light oil and gas. The resulting oil and gas mixture is separated by a cyclone separator 16 to remove solid impurities, and the solid residue is periodically discharged through a sealed gas lock valve 31. The gaseous pyrolysis products enter the condensation recovery system 18, where they are cooled and liquefied by multi-stage condenser tubes 19. The liquid products then enter the oil-water separator 21, where an automatic liquid level detector controls an electromagnetic proportional valve 601 to complete oil-water separation. Finally, the remaining non-condensable gases are introduced into the tail gas treatment unit 701 for purification and incineration. The entire system's operation is controlled in real time by the integrated central controller 25 based on feedback from the temperature monitoring sensor 13, pressure sensor 14, and liquid level sensor 26. This is achieved through a closed-loop precise control of the entire chain using a PID algorithm, thus realizing the resource utilization, high-value recycling, and green recycling of plastic waste.

[0040] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A device for catalytic depolymerization and recycling of plastic waste, characterized in that, include: A frame (1) is provided with a feed hopper (2). The outlet of the feed hopper (2) is connected to a pretreatment device (3). The pretreatment device (3) includes a crushing chamber (4) and multiple sets of roller crushing components (5) arranged in the crushing chamber (4). A screw conveyor mechanism (6) is provided at the bottom of the pretreatment device (3). The screw conveyor mechanism (6) is connected to a catalytic depolymerization reactor (7). A rotating stirring shaft (8) is provided inside the catalytic depolymerization reactor (7). A multi-layered inclined stirring blade (9) is integrated on the rotating stirring shaft (8). The catalytic depolymerization reaction... An electromagnetic induction heating jacket (10) is fitted around the outside of the reactor (7). A catalyst metering device (11) and a pressure regulating valve (12) are connected to the top of the catalytic depolymerization reactor (7). A temperature monitoring sensor (13) and a pressure sensor (14) are provided on the side wall of the catalytic depolymerization reactor (7). A slag outlet (15) is provided at the bottom of the catalytic depolymerization reactor (7), and a gas-liquid separation device (16) is connected to its side. The top of the gas-liquid separation device (16) is connected to a condensation recovery system (18) through a first gas guide pipe (17). The condensation recovery system (18) includes multiple stages connected in series. The condenser (19) and the circulating cooling water chamber (20) located outside the condenser (19) are provided. The end of the condensation recovery system (18) is connected to an oil-water separator (21). The oil-water separator (21) is provided with an oil phase output pipe (22) and a water phase output pipe (23). The bottom of the gas-liquid separation device (16) is provided with a residue collection box (24). The frame (1) is also integrated with a central controller (25). The central controller (25) is connected to the pretreatment device (3), the catalytic depolymerization reactor (7), and the condensation recovery system (18). The catalytic depolymerization reactor (7) is connected to the pretreatment device (3), the catalytic depolymerization reactor (7). The machine is equipped with a liquid level sensor (26), a shock-absorbing base (27) at the bottom of the frame (1), a wear-resistant ceramic coating (28) on the inner wall of the crushing chamber (4), a servo motor (29) driving the rotating stirring shaft (8), a rock wool insulation layer (30) covering the outside of the electromagnetic induction heating jacket (10), a sealing gas lock valve (31) installed at the slag outlet (15), a filter screen (32) on the first air guide pipe (17), a flame arrester (33) at the air inlet of the condensation recovery system (18), and a touch screen (34) integrated into the central controller (25).

2. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The pretreatment device (3) has a cleaning mechanism in the crushing chamber (4), which includes a magnetic separation roller (101) disposed above the roller crushing assembly (5) and a vibrating screen (102) disposed on the side wall of the crushing chamber (4).

3. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The inner wall of the catalytic depolymerization reactor (7) is provided with a guide plate (201), which is staggered with the stirring blade (9) on the rotating stirring shaft (8) to increase the turbulence intensity of the plastic material in the catalytic depolymerization reactor (7).

4. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The catalyst quantitative addition device (11) includes a storage tank (301) equipped with a weighing sensor and a variable frequency screw feeder (302) connected to the bottom of the storage tank (301).

5. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The circulating cooling water chamber (20) of the condensation recovery system (18) is connected to an external cooling tower (401) and a cooling circulation pump (402). The central controller (25) automatically adjusts the flow rate of the cooling circulation pump (402) according to the temperature at the outlet of the circulating cooling water chamber (20).

6. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The gas-liquid separation device (16) is equipped with a cyclone separation inner cylinder (501), which has an inverted conical structure and is used to initially separate pyrolysis gas from liquid residue by centrifugal force.

7. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The oil-water separator (21) is equipped with an automatic liquid level interface detector, and electromagnetic proportional valves (601) are respectively installed on the oil phase output pipe (22) and the water phase output pipe (23).

8. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The frame (1) is provided with an exhaust gas treatment unit (701), which is connected to the end of the condensation recovery system (18) through a second gas guide pipe (702) for activated carbon adsorption and catalytic oxidation treatment of the condensed non-condensable gas.

9. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The bottom of the catalytic depolymerization reactor (7) is provided with a heating belt (801), which is used to maintain the temperature of the slag outlet (15) area and prevent the liquid residue from condensing and clogging during the slag discharge process.

10. The catalytic depolymerization and recycling equipment for plastic waste according to claim 1, characterized in that, The central controller (25) has a built-in heating control program based on PID algorithm, which adjusts the power of the electromagnetic induction heating jacket (10) in real time according to the feedback data of the temperature monitoring sensor (13) to keep the temperature inside the reactor stable in the range of 350°C to 450°C.

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