A waste plastic catalytic reforming device and a reforming method

Abstract

The application provides a waste plastic catalytic reforming device and a reforming method, and belongs to the technical field of waste plastic resource treatment.The technical problems of easy carbon deposition and deactivation of a catalyst, uncontrolled carbon dioxide emission and unstable quality of synthesis gas in a traditional pyrolysis process are solved.The waste plastic catalytic reforming device comprises a glass tube reactor, a copper crucible is arranged in the glass tube reactor, a catalysis-adsorption assembly, a spring heating ring, an electromagnetic induction heating device, an inert gas cylinder and a product collection unit.The catalysis-adsorption assembly comprises a steel ball catalyst filled below the copper crucible in the glass tube, a three-dimensional network structure of the steel ball catalyst provides catalytic active sites, and a calcium oxide cake-shaped adsorption layer is used for adsorbing generated carbon dioxide.The spring heating ring is coaxially wound outside the copper crucible.The heating coil of the electromagnetic induction heating device is arranged around the glass tube reactor.The inert gas cylinder is used for providing inert gas to a reaction system.The product collection unit comprises a conical flask used for drying synthesis gas and an aluminum foil gas collection bag used for storing purified synthesis gas.The waste plastic catalytic reforming device is mainly used for waste plastic pyrolysis.

Description

Technical Field

[0001] This invention belongs to the field of waste plastic resource utilization technology, specifically relating to a waste plastic catalytic reforming device and reforming method. Background Technology

[0002] The continued growth in global plastic consumption has led to a surge in pressure on waste plastic disposal. Current mainstream landfill, incineration, and mechanical recycling technologies all have significant drawbacks: landfills occupy large amounts of land and cause long-term soil pollution; incineration releases toxic pollutants; and mechanical recycling struggles to achieve high-value utilization due to material degradation. In contrast, pyrolysis technology, which converts waste plastics into high-value-added products such as syngas through anaerobic pyrolysis, is considered a more promising solution. However, traditional pyrolysis processes rely on electric or microwave heating, resulting in low energy efficiency and insufficient temperature control precision, easily leading to localized overheating and coking. This results in large fluctuations in the hydrogen-to-carbon monoxide ratio in the products and low carbon utilization.

[0003] Pyrolysis catalysis technology can convert waste plastics into high-value-added products such as alkanes and hydrogen, and is currently a research hotspot. Traditional pyrolysis-catalysis units employ a two-stage design: the pyrolysis stage uses external heating to decompose waste plastics into volatiles, while the catalytic stage uses a fixed-bed catalyst to crack the volatiles and generate the target products. Recently proposed electromagnetic induction heating technology achieves rapid and uniform heating within the material through the eddy current effect, and combined with a liquid heat transfer medium (such as molten salt) to enhance heat transfer, it can significantly improve pyrolysis efficiency. Furthermore, methane and water vapor can undergo a reforming reaction on the surface of an electromagnetically activated metal catalyst, generating syngas with a controllable H2 / CO ratio.

[0004] In existing technologies, while the introduction of steam is used to regulate the reaction pathway, traditional steam inlet designs often result in low activation efficiency due to uneven gas-solid mixing. Furthermore, the lack of effective means to capture the acidic CO2 generated by the reaction not only leads to carbon loss but also contradicts the global goal of carbon neutrality. In addition, traditional powdered or granular catalysts are prone to pore blockage, resulting in rapid carbon buildup and often rapid deactivation. Frequent regeneration further increases operating costs and severely restricts the continuous operation capability of the unit. Summary of the Invention

[0005] In view of this, the present invention aims to provide a waste plastic catalytic reforming device and method to solve the technical problems of easy catalyst carbon deposition and deactivation, runaway carbon dioxide emissions, and unstable syngas quality in traditional pyrolysis processes.

[0006] To achieve the above objectives, according to one aspect of the present invention, a waste plastic catalytic reforming apparatus is provided, comprising: A glass tube reactor containing a copper crucible for holding heated waste plastic particles; The catalytic-adsorption assembly includes: a steel wire ball catalyst, filled in a glass tube below a copper crucible, whose three-dimensional network structure provides catalytic active sites; and a calcium oxide cake-shaped adsorption layer, pressed and fixed below the steel wire ball catalyst, for adsorbing carbon dioxide generated in the reaction. A spring heating coil is coaxially wound around the outside of a copper crucible; an electromagnetic induction heating device has a heating coil surrounding a glass tube reactor, which heats the steel wire ball catalyst through eddy currents; together with the spring heating coil, they form a composite heating system. An automatic feeder, connected to the inlet of the glass tube reactor, can continuously transport waste plastic granules to the copper crucible; An inert gas cylinder, connected to a glass tube reactor via a pipeline, is used to supply inert gas to the reaction system; The product collection unit includes: a conical flask containing silica gel desiccant, connected to the outlet of the glass tube reactor for drying syngas; and an aluminum foil gas collection bag connected in series with the conical flask for storing the purified syngas.

[0007] Furthermore, the gas inlet of the glass tube reactor includes an independent first gas source and a second gas source, which are respectively connected to the glass tube reactor through control valves. The first gas source is an inert gas cylinder, whose steam injection end is located between the copper crucible and the steel wire ball catalyst. The second gas source is a steam generator, whose purge gas inlet is located on the glass tube reactor near the automatic feeder end.

[0008] Furthermore, the spring heating coil is a spiral structure made of nickel-chromium alloy resistance wire, and its heating power and heating temperature can be independently adjusted. It works in conjunction with the electromagnetic induction heating device to achieve gradient temperature control of the copper crucible and the steel wire ball catalyst.

[0009] Furthermore, the calcium oxide cake-shaped adsorption layer is formed by pressing CaO powder and kaolin binder at a mass ratio of 4:1, with a thickness of 10 mm and uniformly opened through-pores with a diameter of 1 mm and a density of 7 per square centimeter on the surface.

[0010] Furthermore, the steel wire ball catalyst is formed by modifying stainless steel wire by etching with 15% hydrochloric acid for 45 minutes and then oxidizing at high temperature in a furnace at 550℃ for 2.5 hours. It has a specific surface area of ​​85-120 m² / g, a porosity of 40%-55%, and an iron oxide active layer loaded on its surface.

[0011] Furthermore, the steam co-processing unit delivers steam to the reaction chamber through the purge gas inlet; the steam co-processing unit is equipped with an electrically heated steam generator, whose internal heating element is made of nickel-chromium alloy wire, the water inlet is connected to the water source by a stainless steel corrugated pipe, and the outlet is connected to the purge gas inlet by a silicone tube with an inner diameter of 5mm; the steam flows smoothly into the quartz tube from above at a flow rate of 10ml / min, and the purge gas inlet is close to the copper crucible, with the vertical distance controlled at 7cm.

[0012] According to another aspect of the present invention, a method for catalytic reforming of waste plastics using the above-described apparatus is provided, comprising the following steps: S1, waste plastic granules are conveyed to the copper crucible by an automatic feeder at a feeding rate of 0.1 g / h; S2, activate the spring heating coil and electromagnetic induction heating device to control the reaction chamber to heat to the predetermined temperature according to the set program; S3, turn on the argon gas source of the inert gas cylinder, set the inlet flow rate to 50ml / min, turn on the steam generator, and introduce steam at a flow rate of 10ml / min. The gas generated by the pyrolysis of waste plastic passes through the high-temperature steel wire ball catalyst catalytic reforming and the calcium oxide cake adsorption layer to remove carbon dioxide. S4, the synthesis gas exiting the reaction chamber is passed through a conical flask containing dry silica gel to remove water vapor, and then collected by an aluminum foil gas collection bag. Unreacted solid residue is retained in the steel wire ball catalyst.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. Synergistic effect of catalysis and adsorption: The three-dimensional network structure of the iron-based steel wire ball porous catalyst layer significantly improves the density of active sites. Combined with the co-current injection of water vapor, it makes the volume ratio in the syngas stable and controllable. The calcium oxide cake adsorption layer increases the gas-solid contact area and improves CO2 capture efficiency through its internal porous design.

[0014] Anti-carbon buildup and long lifespan: The gradient pore structure of the steel wire ball catalyst effectively inhibits carbon deposition and greatly reduces the catalyst activity decay after long-term operation; the mechanical strength of the calcium oxide cake is significantly better than that of traditional adsorption powder, which can effectively avoid system pipeline blockage caused by adsorbent breakage.

[0015] Low cost and easy operation The design employs a single steam inlet and modular adsorption units, reducing equipment complexity and maintenance costs. The coordinated control of resistance heating and electromagnetic induction heating significantly reduces energy consumption compared to traditional electric heating.

[0016] Environmental friendliness: By using in-situ carbon dioxide adsorption and adsorbent recycling, the carbon emission intensity of the system is effectively reduced; key components are reduced to minimize pyrolysis oil mist pollution, ensuring long-term stable operation of the unit. Attached Figure Description

[0017] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the structure of a waste plastic catalytic reforming reactor according to the present invention; Figure 2 This is a flowchart of an experimental method for catalytic reforming of waste plastics according to the present invention.

[0018] 1. Automatic feeder; 2. Spring heating coil temperature controller; 3. Electromagnetic induction heating device; 4. Glass tube reactor (reaction chamber); 5. Conical flask (drying unit, filled with silica gel desiccant); 6. Aluminum foil gas collection bag (collection unit); 7. Purge gas inlet; 8. Waste plastic granules; 9. Copper crucible; 10. Spring heating coil; 11. Steel wool catalyst (steel wool modified structure); 12. Calcium oxide cake adsorption layer; 13. Inert gas cylinder. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other, and the described embodiments are only some embodiments of the present invention, not all embodiments.

[0020] It should be noted that the descriptions of "left," "right," "left side," "right side," "upper part," "lower part," "top," and "bottom" in this invention are defined based on the orientation or positional relationships shown in the accompanying drawings. They are merely for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the described structure must be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0021] In the description of this invention, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] Referring to the accompanying drawings, this embodiment provides a waste plastic catalytic reforming reactor, comprising: The reaction chamber is constructed from a high-purity quartz glass tube reactor 4, which possesses excellent high-temperature resistance, allowing it to stably withstand extreme temperatures up to 800°C during catalytic reforming reactions. Its strong chemical stability effectively prevents chemical reactions with various substances within the reaction system, ensuring the purity and stability of the reaction environment. Furthermore, the transparency of the glass tube provides operators with convenient and direct observation of the internal reaction process, allowing real-time monitoring of dynamic changes in the material state and providing crucial information for precise control of the reaction process. During installation, the high-temperature glass tube reactor 4 is mounted on an electromagnetic induction heating support frame. Adjustable bolts at the bottom of the frame allow for precise height adjustment, with a height error controllable within ±1mm. The glass tube is connected to external components at both ends via stainless steel 316L flanges with integrated sealing gaskets. The sealing gaskets are made of high-temperature and corrosion-resistant polytetrafluoroethylene (PTFE), effectively improving the airtightness of the device. During installation, the connection surfaces of the glass tube and flange are first carefully cleaned to ensure they are free of impurities and scratches. Next, a layer of sealant is applied, and the sealing gasket is carefully placed and positioned accurately. Finally, high-strength bolts are used for installation using a diagonal tightening method, tightening the bolts gradually in multiple stages. After each tightening, a hexagonal torque wrench is used to check the torque, ensuring that the torque of each bolt is uniform and consistent, controlling the torque deviation within ±5 N·m. Finally, the airtightness of the device is checked to prevent leakage of reactive gases.

[0023] The composite heating system consists of a spring heating coil 10 and an electromagnetic induction heating device 3. The spring heating coil 10 generates Joule heat by producing a rated current to heat the copper crucible 9, precisely controlling the temperature of the first pyrolysis reaction. The electromagnetic induction heating device 3 operates based on the principle of electromagnetic induction, releasing Joule heat by generating eddy currents in the steel wire ball catalyst 11 to achieve rapid and efficient heating of the reaction system. The electromagnetic induction heating coil is tightly and evenly wound around the outside of the glass tube according to design requirements. The coil uses high-purity copper wire, which is wrapped with insulating material. The cross-sectional area of ​​the coil is rationally selected based on the heating power and current density, approximately 30 square millimeters. The number of turns is 20. This composite heating method not only allows the heat generated by the two heaters to be superimposed to increase the calorific value and accelerate the reaction efficiency, but also places the reaction in the same space, achieving heat sharing, extending the reaction path, and making the reaction more complete.

[0024] The catalytic-adsorption assembly has a layered structure, with an upper layer of iron-based porous steel wire ball catalyst 11 and a lower layer of calcium oxide cake-shaped adsorption layer 12. The iron-based porous steel wire ball catalyst 11 is prepared from stainless steel wire balls through a special modification treatment. Specifically, the stainless steel wire balls are first immersed in a 15% hydrochloric acid solution for 45 minutes, effectively removing impurities from the surface of the wire balls and etching out numerous micropores, significantly increasing their specific surface area. Subsequently, the etched wire balls are placed in a high-temperature furnace and oxidized at 550°C for 2.5 hours, forming an iron oxide coating on their surface, which significantly enhances catalytic activity. During installation, the iron-based porous steel wire ball catalyst 11 and the calcium oxide cake-shaped adsorption layer 12 are placed on a specific support structure inside a glass tube and fixed to the quartz glass tube by tight pressing, ensuring the stability of the catalytic-adsorption bed position during the reaction process.

[0025] In the preparation of the calcium oxide cake-shaped adsorption layer 12, CaO powder and kaolin binder are mixed at a mass ratio of 4:1, and an appropriate amount of water is added and stirred into a mud-like consistency. The mud-like material is then pressed into a cake-shaped structure with a thickness of 10 mm using a mold. The pressure during pressing is controlled at 12 MPa to ensure good mechanical strength of the adsorption layer. Next, through-holes with a diameter of 1 mm, uniformly distributed, and a density of 7 per square centimeter are machined using a drilling device. During installation, it is placed below the catalytic bed, maintaining a 7 mm gap between them. At the contact point between the adsorption layer and the glass tube, multiple layers of high-temperature resistant sealing asbestos rope are wrapped to ensure a sealing effect and prevent gas leakage.

[0026] The steam co-processing unit injects steam into the reaction chamber through the purge gas inlet 7. This system is equipped with an independent electrically heated steam generator, whose internal heating element is made of corrosion-resistant nickel-chromium alloy wire. The generator inlet is securely connected to the water source via a corrosion-resistant stainless steel corrugated pipe. The stainless steel corrugated pipe has good flexibility and corrosion resistance, effectively preventing leakage. The steam generator outlet is connected to the single inlet 7 at the top of the reaction chamber via a high-temperature resistant silicone tube. The silicone tube has an inner diameter of 5mm, and the connection is secured with stainless steel clamps, using a torque wrench to ensure a tight connection. The steam inlet is precisely positioned at the top of the glass tube reactor 4, adjacent to the copper crucible 9. During installation, the distance between the steam inlet and the copper crucible is precisely controlled to within 7cm by fine-tuning the steam inlet mounting bracket. This method ensures that the steam can quickly mix with the vaporized reactants without interfering with the plastic pyrolysis reaction. Experimental results show that compared with traditional steam inlet locations, this scheme can improve the overall reaction efficiency by 10% and increase the content of the target component in the product by 5%. In terms of steam utilization efficiency, the amount of steam consumed per unit time is reduced by 25%, and the effective use time of the drying conical flask is extended by 30%. In addition, this layout can stabilize the gas flow rate, and because the steam inlet is far away from the electromagnetic induction heating area, it is beneficial for the reaction gas to be mixed evenly before entering the steel wire ball catalyst layer, which significantly improves the safety of system operation and the uniformity of gas distribution.

[0027] The product collection unit consists of a conical flask 5 containing silica gel desiccant for drying the gaseous product and an aluminum foil gas collection bag 6 for storing the dried syngas. A high-temperature resistant and chemically corrosion-resistant glass conical flask 5 with a volume of 750 mL is placed appropriately below the outlet of the reaction chamber, filled with silica gel desiccant to approximately 2 / 3 of its volume. The reaction chamber is connected to the conical flask 5 via a glass connecting tube with an inner diameter of 2 mm. The longer tube is inserted into the silica gel desiccant to ensure sufficient contact with water vapor, while the shorter tube extends out of the conical flask and connects to the gas bag. The connection is sealed with sealant to prevent gas leakage. The aluminum foil gas collection bag 6, with a volume of 10 L, is connected to the gas outlet via a sealing joint with an internal rubber sealing ring. During installation, the gas bag is evacuated to a vacuum using a gas pump beforehand, and then placed on a horizontal surface to ensure smooth valve opening and closing for convenient collection and storage of syngas.

[0028] Specifically, the continuous feeding of the automatic feeder 1 relies on a screw conveyor and a matching hopper. The conveying pipeline is made of corrosion-resistant stainless steel, and the inner wall is polished to reduce friction during waste plastic conveying. In this embodiment, the stepper motor is adjusted to the lowest speed, and after multiple measurements and data analysis, the plastic granule feeding rate is approximately 0.1 g / h. The outlet of the conveying pipeline is connected to the inlet of the feeding channel using a high-temperature resistant and aging-resistant silicone tube. The inner diameter of the silicone tube is selected as 2 mm according to the principle of matching material flow rate and pipe diameter to ensure smooth material passage. During connection, plastic pipe clamps are fitted at both ends and tightened to prevent material leakage. The silicone tube is regularly inspected daily, and any aging or damage is promptly replaced to ensure stable feeding.

[0029] An inert gas supply assembly, connected to the reaction quartz tube, is used to create an oxygen-free environment within the reaction chamber.

[0030] Specifically, the inert gas supply assembly can be a combination of a gas cylinder and a gas pump, along with a flow meter, to deliver inert gas to the reaction chamber. Argon is selected as the inert gas. For the specific connection method, the output of the gas pump can be connected to the feed channel of component 1. The feed channel empties the air from the continuous feeding device and the reaction chamber, thus creating an oxygen-free environment. It is important to emphasize that for the creation of an oxygen-free environment, all connections in this application must be airtight to prevent leaks that could compromise the oxygen-free environment.

[0031] In this embodiment, during the system preheating stage, the operator activates the electromagnetic induction heating device 3 and the spring heating coil temperature controller 2. The spring heating coil temperature controller 2 sets the heating program, causing the copper crucible 9 to heat up to 500°C at a rate of approximately 5°C / min. During the heating process, the temperature inside the copper crucible 9 is monitored in real time by a high-precision thermocouple sensor to ensure that the temperature deviation is controlled within ±5°C, guaranteeing the stability and accuracy of the heating process and providing a suitable initial temperature environment for the subsequent plastic pyrolysis and catalytic reforming reactions.

[0032] In this embodiment, during the atmosphere replacement step, the valve of inert gas cylinder 13 is first opened, and the flow rate of inert argon gas is controlled by a flow meter to be introduced into the reaction chamber at a rate of approximately 500 mL / min for about 15 minutes to fully purge the air from the reaction chamber. Then, the inert gas flow controller is set to a flow rate of 50 mL / min, and a steam generator is turned on according to a pre-set ratio, injecting steam into the reaction chamber at a rate of 10 mL / min to mix with the inert gas, creating an atmosphere that meets the reaction requirements and ensuring that the reaction proceeds under oxygen-free conditions with an appropriate amount of steam present.

[0033] In this embodiment, during the continuous reaction process, the automatic feeder 1 feeds waste plastic particles 8 into the reaction chamber at a rate of 0.1 g / h. The waste plastic particles first undergo a pyrolysis process in the copper crucible 9. As the gaseous products generated by pyrolysis descend, they pass sequentially through the iron-based steel wire ball catalyst 11 for catalytic reforming. Subsequently, the carbon dioxide generated by the reaction is adsorbed by the calcium oxide cake-shaped adsorption layer 12 below, realizing a continuous reaction process in which the material sequentially undergoes high-temperature pyrolysis of plastic, catalytic reforming of pyrolysis products, and chemical adsorption of carbon dioxide.

[0034] In this embodiment, during the product fractionation and collection stage, after the pyrolysis gas passes through the calcium oxide adsorption layer to adsorb CO2, it first flows through a connecting pipe into a conical flask 5 containing silica gel desiccant. As the gas flows through the silica gel desiccant in the conical flask, the moisture is effectively adsorbed, thus achieving the syngas drying process. During this process, the state of the silica gel desiccant in the conical flask 5 is closely monitored. If obvious signs of moisture absorption are found, it is replaced promptly to ensure the drying effect. The dried syngas is then piped into an aluminum foil gas collection bag 6 for collection.

[0035] In this embodiment, during adsorbent regeneration, the adsorption performance of the calcium oxide adsorption layer is monitored online or periodically. When the calcium oxide adsorption capacity reaches 80% saturation, the switching process is initiated. The device is disassembled according to the procedure, the connection between the current adsorption unit and the reaction chamber is removed, and a backup adsorption unit is installed, switching the reaction gas to the backup adsorption unit for carbon dioxide adsorption. The saturated calcium oxide adsorption layer is removed and placed in a high-temperature calcination furnace, calcined at approximately 800°C for about 2 hours to desorb the adsorbed carbon dioxide, thus regenerating the adsorbent. After cooling, the regenerated calcium oxide adsorption layer is reinstalled into the device for the next cycle, effectively reducing operating costs and improving the sustainability of the device.

[0036] According to another aspect of the present invention, a test method using the above-described waste plastic pyrolysis-reforming reactor is provided, comprising the following steps: S1. Equipment installation and commissioning: Place the waste plastic pyrolysis device on a stable test bench, connect the pipes and lines between each component, check the equipment operation, and adjust the parameters of each device to the initial state. S2. Atmosphere replacement and preheating: Open the valve of inert gas cylinder 13, and use a flow meter to control the inert gas to flow into the reaction chamber at a rate of 500 mL / min for 15 minutes to purge the air. Then adjust the flow rate to 50 mL / min. Next, start the electromagnetic induction heating device 3 and the spring heating coil temperature controller 2, and follow the heating program to heat the copper crucible 9 to 300℃ at a rate of 5℃ / min. Maintain the temperature for 15 minutes to preheat the reaction chamber. After preheating, turn on the steam generator to inject steam. S3. Feeding and Reaction: Waste plastic granules 8 are continuously fed into the reaction chamber via automatic feeder 1 at a rate of 0.1 g / h. During the reaction, the temperature data of each thermocouple is closely monitored to maintain the reaction temperature in the first and second steps at the predetermined experimental temperature.

[0037] S4. Product Collection and Monitoring: After CO2 is adsorbed by the calcium oxide cake adsorption layer 12, the pyrolysis gas flows through a connecting tube into a conical flask 5 containing silica gel desiccant for drying. After drying, it is introduced into an aluminum foil gas collection bag 6 for collection. Finally, the collected syngas is analyzed by gas chromatography, and the composition and content of each component are recorded.

[0038] S5. Reaction Completion: After the predetermined reaction time, stop feeding the automatic feeder 1. Continue operating the electromagnetic induction heating device 3 and the spring heating coil temperature controller 2 to ensure that the remaining material in the reaction chamber reacts completely. Subsequently, close the valves of the electromagnetic induction heating device 3, the spring heating coil temperature controller 2, the steam generator, and the inert gas cylinder 13. After the reaction chamber cools to room temperature, disassemble all components, and the test is complete.

[0039] Specifically, to ensure that the electromagnetic induction heating coil can adapt to the height of the steel wool catalyst 11, the electromagnetic induction heating device 3 is placed on a scissor lift platform, which is fixed to a moving platform. During the experiment, the forward, backward, left, and right movements of the reactor can be directly achieved through the moving platform; the up and down movements of this device are achieved by operating the scissor lift platform.

[0040] The controllers, sensors, and control programs mentioned above are all existing technologies and will not be elaborated upon here.

[0041] The embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A waste plastic catalytic reforming device, characterized in that, The device includes: A glass tube reactor (4) is provided inside a copper crucible (9) for holding heated waste plastic particles (8). The catalytic-adsorption assembly includes a steel wire ball catalyst (11) filled below a copper crucible (9) in a glass tube reactor (4). Its three-dimensional network structure provides catalytic active sites. The steel wire ball catalyst (11) is formed by modifying stainless steel wire by etching with 15% hydrochloric acid for 45 min and then oxidizing at high temperature in a furnace at 550℃ for 2.5 h. Its specific surface area is 85-120 m². 2 / g, with a porosity of 40%-55%, and an iron oxide active layer loaded on the surface; a calcium oxide cake-shaped adsorption layer (12), which is pressed and fixed below the steel wire ball catalyst (11) for adsorbing carbon dioxide generated in the reaction; A spring heating coil (10) is coaxially wound around the outside of a copper crucible (9); an electromagnetic induction heating device (3) is set with its heating coil surrounding a glass tube reactor (4) to heat the steel wire ball catalyst (11) through eddy currents; together with the spring heating coil (10), they form a composite heating system; An automatic feeder (1) is connected to the inlet end of the glass tube reactor (4) and can continuously convey waste plastic particles (8) to the copper crucible (9). An inert gas cylinder (13) is connected to a glass tube reactor (4) via a pipeline to provide inert gas to the reaction system; The product collection unit includes: a conical flask (5) containing silica gel desiccant, connected to the bottom outlet of the glass tube reactor (4) for drying syngas; an aluminum foil gas collection bag (6) connected in series with the conical flask (5) for storing purified syngas; the gas inlet of the glass tube reactor (4) is provided with an independent first gas source and a second gas source, which are respectively connected to the glass tube reactor (4) through control valves, wherein: the first gas source is an inert gas cylinder (13), whose inert gas injection end is located between the copper crucible (9) and the steel wire ball catalyst (11); the second gas source is a steam generator, whose purge gas inlet (7) is located on the glass tube reactor (4) near the automatic feeder (1).

2. The apparatus according to claim 1, characterized in that: The spring heating coil (10) is a spiral structure made of nickel-chromium alloy resistance wire. Its heating power and heating temperature can be independently adjusted, and it works in conjunction with the electromagnetic induction heating device (3) to achieve gradient temperature control of the copper crucible (9) and the steel ball catalyst (11).

3. The apparatus according to claim 1, characterized in that: The calcium oxide cake-shaped adsorption layer (12) is formed by pressing CaO powder and kaolin binder at a mass ratio of 4:1, with a thickness of 10 mm and through-pores with a diameter of 1 mm and a density of 7 per square centimeter evenly opened on the surface.

4. The apparatus according to claim 1, characterized in that: The steam coordinating unit delivers steam to the reaction chamber through the purge gas inlet (7); the steam coordinating unit is equipped with an electrically heated steam generator, whose internal heating element is a nickel-chromium alloy wire, the water inlet is connected to the water source by a stainless steel corrugated pipe, and the outlet is connected to the purge gas inlet (7) by a silicone tube with an inner diameter of 5 mm; the steam flows smoothly into the quartz tube from above at a flow rate of 10 ml / min, and the purge gas inlet (7) is close to the copper crucible, with the vertical distance controlled at 7 cm.

5. A method for catalytic reforming of waste plastics using the apparatus according to any one of claims 1-4, characterized in that: S1, waste plastic granules (8) are conveyed to copper crucible (9) by automatic feeder (1) at a feeding rate of 0.1 g / h; S2, start the spring heating coil (10) and the electromagnetic induction heating device (3) to control the reaction chamber to heat to the predetermined temperature according to the set program; S3, turn on the argon gas source of the inert gas cylinder (13), set the inlet flow rate to 50 ml / min, turn on the steam generator, and introduce steam at a flow rate of 10 ml / min. The gas generated by the pyrolysis of waste plastic passes through the high temperature steel wire ball catalyst (11) for catalytic reforming and the calcium oxide cake adsorption layer (12) to remove carbon dioxide. S4, the synthesis gas flowing out of the reaction chamber outlet passes through a conical flask (5) containing dry silica gel to remove water vapor, and is then collected by an aluminum foil gas collection bag (6). The unreacted solid residue is retained in the steel wire ball catalyst (11).

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