Waste plastic catalytic reforming device and reforming method

Abstract

The invention provides a waste plastic catalytic reforming device and a reforming method, and belongs to the technical field of waste plastic resourceful treatment. The technical problems that in a traditional pyrolysis process, a catalyst is prone to carbon deposition and deactivation, carbon dioxide emission is out of control, and synthesis gas quality is unstable are solved. The waste plastic catalytic reforming device comprises a glass tube reactor, wherein a copper crucible is arranged in the glass tube reactor; the catalysis-adsorption assembly comprises a steel wire ball catalyst which is filled below the copper crucible in the glass tube, and a three-dimensional network structure of the steel wire ball catalyst provides catalytic active sites; the calcium oxide cake-shaped adsorption layer is used for adsorbing carbon dioxide generated by reaction; the spring heating ring is coaxially wound on the outer side of the copper crucible; a 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 for the reaction system; the product collecting unit comprises a conical flask used for drying the synthesis gas; and the aluminum foil gas production bag is used for storing the purified synthesis gas. The device is mainly used for waste plastic pyrolysis.

Description

Technical Field

[0001] The present invention belongs to the technical field of waste plastic resource treatment, and particularly relates to a waste plastic catalytic reforming device and a reforming method. Background Art

[0002] The continuous growth of global plastic consumption has led to a sharp increase in the pressure of waste plastic treatment. The current mainstream landfill, incineration, and mechanical recycling technologies all have significant defects: landfilling occupies a large amount of land and causes long-term soil pollution, the incineration process releases toxic pollutants, and mechanical recycling is difficult to achieve high-value utilization due to the deterioration of material properties. In contrast, pyrolysis technology converts waste plastics into high-value-added products such as syngas through anaerobic cracking, and is regarded as a more promising solution. However, traditional pyrolysis processes rely on electric heating or microwave heating, with low energy efficiency and insufficient temperature control accuracy, which easily causes local overheating and coking, resulting in large fluctuations in the ratio of hydrogen to carbon monoxide in the products and low carbon utilization rate.

[0003] Pyrolysis catalytic technology can convert waste plastics into high-value-added products such as alkanes and hydrogen, and is a current research hotspot. Traditional pyrolysis-catalytic devices adopt a two-stage design: the pyrolysis section decomposes waste plastics into volatile components through external heating, and the catalytic section cracks the volatile components through a fixed-bed catalyst to generate target products. The electromagnetic induction heating technology proposed in recent years can achieve rapid and uniform heating inside the material through the eddy current effect, and combines a liquid heat carrier medium (such as molten salt) to strengthen heat transfer, which can significantly improve the pyrolysis efficiency. In addition, the reforming reaction of methane and water vapor can occur on the surface of an electromagnetically activated metal catalyst to generate syngas with a controllable H2 / CO ratio.

[0004] In the prior art, although the introduction of water vapor is used to adjust the reaction path, the traditional steam inlet design often results in low activation efficiency due to uneven gas-solid mixing. At the same time, there is a lack of effective means for capturing the acidic gas CO2 generated by the reaction, resulting in carbon loss. In addition, traditional powder or granular catalysts have a fast carbon deposition rate due to easy pore blockage, often quickly deactivate, and frequent regeneration further increases the operating cost, seriously restricting the continuous operation ability of the device. 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 carbon deposition and deactivation of the catalyst, out-of-control carbon dioxide emissions, and unstable syngas quality in the traditional pyrolysis process.

[0006] To achieve the above object, according to one aspect of the present invention, there is provided a waste plastic catalytic reforming device, comprising: A glass tube reactor, inside which there is a copper crucible for accommodating heated waste plastic particles; The catalytic-adsorption component includes: a steel wool catalyst filled below the copper crucible in a glass tube, and its three-dimensional network structure provides catalytic active sites; a calcium oxide cake-shaped adsorption layer, which is pressed and fixed below the steel wool catalyst for adsorbing the carbon dioxide generated by the reaction. A spring heating coil is coaxially wound outside the copper crucible; an electromagnetic induction heating device, whose heating coil is arranged around the glass tube reactor, and heats the steel wool catalyst through eddy current; it constitutes a composite heating system together with the spring heating coil. An automatic feeder is connected to the inlet end of the glass tube reactor and can continuously transport waste plastic particles to the copper crucible. An inert gas cylinder is connected to the glass tube reactor through a pipeline for providing inert gas to the reaction system. The product collection unit includes: a conical flask filled with silica gel desiccant, which is connected to the outlet of the glass tube reactor for drying the syngas; an aluminum foil gas collection bag, which is 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, where: the first gas source is an inert gas cylinder, and its steam injection end is located between the copper crucible and the steel wool catalyst; the second gas source is a water vapor generator, and its purge gas inlet is located at the end of the glass tube reactor near the automatic feeder.

[0008] Furthermore, the spring heating coil is made of a nickel-chromium alloy resistance wire wound into a spiral structure, and its heating power and heating temperature can be independently regulated, and cooperate with the electromagnetic induction heating device to realize the gradient temperature zone control of the copper crucible and the steel wool catalyst.

[0009] Furthermore, the calcium oxide cake-shaped adsorption layer is pressed from CaO powder and kaolin binder in a mass ratio of 4:1, with a thickness of 10 mm, and through holes with a pore diameter of 1 mm and a density of 7 per square centimeter are evenly opened on the surface.

[0010] Furthermore, the steel wool catalyst is formed by modifying stainless steel wire by etching with 15% hydrochloric acid for 45 min and high-temperature oxidation in a high-temperature furnace at 550 °C for 2.5 h. Its specific surface area is 85 - 120 m² / g, the porosity is 40% - 55%, and the surface is loaded with an iron oxide active layer.

[0011] Furthermore, the water vapor synergy unit conveys water vapor to the reaction cavity through the purge gas inlet; the water vapor synergy unit is equipped with an electrically heated water vapor generator, the internal heating element thereof selects 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 by a silica gel tube with an inner diameter of 5 mm; the water vapor flows in smoothly from above the quartz tube at a flow rate of 10 ml / min, the purge gas inlet is adjacent to the copper crucible, and the vertical distance is controlled at 7 cm.

[0012] According to another aspect of the present invention, there is provided a method for catalytic reforming of waste plastics using the above device, comprising the following steps: S1, conveying waste plastic particles to the copper crucible through an automatic feeder at a feeding rate of 0.1 g / h; S2, starting the spring heating coil and the electromagnetic induction heating device, and controlling the reaction cavity to be heated to a predetermined temperature according to a set program; S3, opening the argon gas source of the inert gas cylinder, setting the inlet gas flow rate to 50 ml / min, opening the water vapor generator, and introducing water vapor at a flow rate of 10 ml / min. The gas generated by the pyrolysis of waste plastics is catalytically reformed by a high-temperature steel wool catalyst and the carbon dioxide is removed by a calcium oxide cake-shaped adsorption layer in sequence; S4, after the syngas discharged from the reaction cavity outlet removes water vapor through a conical flask filled with drying silica gel, it is collected by an aluminum foil gas sampling bag, and the unreacted solid residue remains in the steel wool catalyst.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. Catalytic-adsorption synergistic enhancement: The three-dimensional network structure of the iron-based steel wool porous catalytic layer significantly increases the density of active sites. Combined with the smooth injection of water vapor, the volume ratio in the syngas is stable and controllable; the calcium oxide cake-shaped adsorption layer increases the gas-solid contact area through an internal porous design, improving the CO2 capture efficiency.

[0014] Anti-coking and long life: The gradient pore structure of the steel wool catalyst effectively inhibits coking formation, greatly reducing the catalyst activity attenuation phenomenon after long-term operation; the mechanical strength of the calcium oxide cake is significantly better than that of traditional adsorption powders, effectively avoiding system pipeline blockage caused by adsorbent fragmentation.

[0015] Low cost and easy operation Adopting a single water vapor inlet and a modular adsorption unit design reduces the equipment complexity and maintenance cost; the synergistic control of resistance heating and electromagnetic induction heating significantly reduces the energy consumption compared with traditional electric heating.

[0016] Environmental friendliness: Effectively reduce the carbon emission intensity of the system through in-situ carbon dioxide adsorption and adsorbent recycling and regeneration; reduce the pollution of key components by pyrolysis oil mist to ensure the long-term stable operation of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings forming a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments and descriptions thereof of the present invention are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings: Figure 1 is a schematic structural diagram of a waste plastic catalytic reforming reaction device according to the present invention; Figure 2 is a flowchart of a waste plastic catalytic reforming experimental method according to the present invention.

[0018] Automatic feeder; 2. Spring heating coil temperature controller; 3. Electromagnetic induction heating device; 4. Glass tube reactor (reaction cavity); 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 particles; 9. Copper crucible; 10. Spring heating coil; 11. Steel wool catalyst (modified structure of steel wool); 12. Calcium oxide cake-shaped adsorption layer; 13. Inert gas cylinder. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0019] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention. It should be noted that, without conflict, the embodiments and features in the embodiments of the present invention may be combined with each other. The described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0020] It should be noted that the descriptions of the present invention in terms of directions such as "left", "right", "left side", "right side", "upper part", "lower part", "top", "bottom", etc. are all defined based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the described structure must be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation to the present invention. In the description of the present invention, the meaning of "a plurality" is more than two, unless otherwise specifically defined.

[0021] In the description of the present invention, unless otherwise clearly defined and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0022] Referring to the accompanying drawings to illustrate this embodiment, according to one aspect of the present invention, a waste plastic catalytic reforming reaction device is provided, including: A reaction cavity, which is composed of a high-temperature resistant glass tube reactor 4 made of high-purity quartz glass. This glass material has excellent high-temperature resistance characteristics and can stably withstand an extreme high-temperature environment of up to 800 °C during the catalytic reforming reaction. At the same time, its strong chemical stability can effectively avoid chemical reactions with various chemical substances in the reaction system, ensuring the purity and stability of the reaction environment. In addition, the transparent nature of the glass tube provides convenience for operators to directly observe the internal reaction process, enabling real-time observation of the dynamic changes in the material state and providing a key basis for the precise control of the reaction process. During installation, the high-temperature resistant glass tube reactor 4 is placed on a supporting bracket for electromagnetic induction heating. The bottom of the bracket is equipped with adjustable bolts. By precisely adjusting the bolts, the height of the bracket can be accurately adjusted, and the height error can be controlled within ±1 mm. Both ends of the glass tube are connected to external components through stainless steel 316L flanges with attached sealing gaskets. The sealing gasket is made of polytetrafluoroethylene with high temperature resistance and corrosion resistance, which can effectively improve the airtightness of the device. During the installation operation, first, carefully clean the connection surface between the glass tube and the flange to ensure that the connection surface is free of impurities and scratches. Then, apply a layer of sealant, carefully place the sealing gasket, and make it accurately positioned. Finally, use high-strength bolts to install according to the diagonal tightening method, gradually tighten the bolts in multiple steps. After each tightening, use a hexagonal torque wrench to detect to ensure that the torque of each bolt is uniform and consistent, control the torque deviation within ±5 N·m, and finally detect the airtightness of the device to prevent the leakage of reaction gases.

[0023] A composite heating system, which is composed of a spring heating coil 10 and an electromagnetic induction heating device 3. The spring heating coil 10 generates Joule heat by generating 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 and quickly and efficiently heats the reaction system by generating eddy currents in the steel wool catalyst 11 to release Joule heat. The electromagnetic induction heating coil is wound tightly and evenly around the outside of the glass tube according to the design requirements. The coil is made of high-purity copper wire, and the outside of the wire is wrapped with insulating material. The cross-sectional area of the coil is reasonably selected according to the heating power and current density, about 30 square millimeters. The number of winding turns is 20 turns. This composite heating method can not only make the heat generated by the two heaters superimpose each other to increase the calorific value and accelerate the reaction efficiency, but also place the reaction in the same space to achieve heat sharing, extend the reaction path, and make the reaction more complete.

[0024] The catalytic-adsorption component has a layered structure with an upper layer of iron-based porous steel wool catalyst 11 and a lower layer of calcium oxide disc-shaped adsorption layer 12. The iron-based porous steel wool catalyst 11 is prepared by subjecting a stainless steel wool to special modification treatment. Specifically, first, the stainless steel wool is immersed in a hydrochloric acid solution with a concentration of 15% for 45 minutes of acid etching treatment. This process can effectively remove impurities on the surface of the steel wool and etch out a large number of micropores, significantly increasing its specific surface area. Subsequently, the acid-etched steel wool is placed in a high-temperature furnace and oxidized at a temperature of 550°C for 2.5 hours to form an iron oxide coating on its surface, significantly enhancing the catalytic activity. During installation, the iron-based porous steel wool catalyst 11 and the calcium oxide disc-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 to ensure the stability of the catalytic-adsorption bed layer during the reaction.

[0025] When preparing the calcium oxide disc-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 state. The mud-like material is pressed into a disc-shaped structure with a thickness of 10 mm using a mold, and the pressure during the pressing process is controlled at 12 MPa to ensure that the adsorption layer has good mechanical strength. Then, a punching device is used to process through-holes with a pore diameter of 1 mm, uniform distribution, and a density of 7 per square centimeter. During installation, it is placed below the catalytic bed layer with a spacing of 7 mm between them. At the contact between the adsorption layer and the glass tube, multiple layers of high-temperature-resistant sealing asbestos ropes are wound to ensure the sealing effect and prevent gas leakage.

[0026] Steam co - unit injects steam into the reaction chamber through the purge gas inlet 7. The system is equipped with an independent electrically heated steam generator, and the heating element inside the generator is made of corrosion - resistant nickel - chromium alloy wire. The water inlet of the generator is firmly connected to the water source through a corrosion - resistant stainless - steel corrugated pipe. The stainless - steel corrugated pipe has good flexibility and corrosion resistance, which can effectively prevent water leakage. The outlet of the steam generator is connected to the single inlet 7 at the top of the reaction chamber through a high - temperature resistant silicone tube. The inner diameter of the silicone tube is selected as 5 mm, and the connection is fastened with a stainless - steel pipe clamp and operated with a torque wrench according to the specified torque to ensure a tight connection. The steam inlet is precisely set at the top of the glass tube reactor 4 and adjacent to the copper crucible 9. During installation, by fine - tuning the mounting bracket of the steam inlet, the distance between the steam inlet and the copper crucible is accurately controlled within 7 cm. This method can ensure that the steam can quickly mix with the gasified reaction materials without interfering with the plastic pyrolysis reaction. Through experimental verification, compared with the traditional steam injection position, this scheme can increase 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 steam consumption 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 from the electromagnetic induction heating area, it is beneficial for the reaction gas to be evenly mixed before entering the steel wool catalytic layer, significantly improving the safety and gas distribution uniformity of the system operation.

[0027] Product collection unit consists of a conical flask 5 filled with silica gel desiccant for drying gaseous products and an aluminum foil gas sampling bag 6 for storing the dried syngas. Place a high - temperature and chemical - corrosion - resistant glass conical flask 5 with a volume of 750 mL at an appropriate position below the outlet of the reaction chamber, and fill it with about 2 / 3 of its volume of silica gel desiccant. Connect the reaction chamber and the conical flask 5 through a glass connecting pipe with an inner diameter of 2 mm. The long pipe extends into the silica gel desiccant for sufficient contact with steam, and the short pipe extends out of the conical flask and is connected to the gas bag. The connection part is sealed with sealant to prevent gas leakage. The aluminum foil gas sampling bag 6 is connected to the gas outlet through a sealed joint with a rubber sealing ring inside. The gas bag is made of aluminum foil material with a volume of 10 L. During installation, first use a gas pump to evacuate the gas bag to vacuum, and then place the gas bag on a horizontal plane to ensure smooth opening and closing of the valve 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 silo. The conveying pipeline is made of corrosion-resistant stainless steel, and the inner wall is polished to reduce the friction during the transportation of waste plastics. In this embodiment, the stepper motor is adjusted to the lowest speed. After multiple measurements and data analysis, the plastic particle feeding rate is about 0.1g / h. The discharge port of the conveying pipeline is connected to the inlet end of the feed channel with a high-temperature resistant and aging-resistant silicone tube. The inner diameter of the silicone tube is selected to be 2mm according to the principle of matching material flow and tube diameter to ensure smooth passage of materials. When connecting, plastic pipe clamps are put on both ends and tightened to prevent material leakage. Check the silicone tube regularly on a daily basis, and replace it in time if it is aging or damaged to ensure stable feeding.

[0029] The inert gas supply assembly is connected to the reaction quartz tube and is used to create an oxygen-free environment in the reaction chamber.

[0030] Specifically, the inert gas supply component can choose the method of a gas cylinder and gas pump, and cooperate with a flow meter to deliver inert gas to the reaction chamber, and argon is selected as the inert gas. As for the specific connection method, the output end of the gas pump can be connected to the feed channel of 1, and the air in the continuous feeding device and the reaction chamber is emptied through the feed channel to create an oxygen-free environment. It should be emphasized here that for the manufacture of an oxygen-free environment, the joints of each part of the present application should ensure airtightness to prevent leakage from occurring, which may cause the oxygen-free environment to be unable to be guaranteed.

[0031] In this embodiment, during the system preheating stage, the operator starts 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 to heat the copper crucible 9 to 500°C at a rate of about 5°C / min. During the heating process, the temperature in 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, thereby ensuring the stability and accuracy of the heating process and providing a suitable initial temperature environment for the subsequent plastic cracking and catalytic reforming reactions.

[0032] In this embodiment, in the atmosphere replacement step, first open the valve of the inert gas bottle 13, and control the flow rate of the inert gas argon gas through the flow meter to pass into the reaction chamber at a rate of about 500mL / min, and the duration is about 15 minutes to fully evacuate the air in the reaction chamber. After that, change the flow value set by the inert gas flow controller to 50mL / min, and then turn on the water vapor generator according to the preset ratio, so that water vapor is injected into the reaction chamber at a rate of 10ml / min, mixed with the inert gas, and create an atmosphere environment that meets the reaction requirements, ensuring that the reaction is carried out under the condition of oxygen-free and with the participation of an appropriate amount of water vapor.

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

[0034] In this embodiment, in the product classification and collection link, after the pyrolysis gas adsorbs CO2 through the calcium oxide adsorption layer, it first flows into the conical flask 5 filled with silica gel desiccant through the connecting pipe. When the gas flows through the silica gel desiccant in the conical flask, the moisture in it is effectively adsorbed, thus realizing the drying process of the syngas. During this process, closely monitor the state of the silica gel desiccant in the conical flask 5. If it is found that the desiccant shows obvious signs of dampness, replace it in time to ensure the drying effect. The dried syngas is collected by being introduced into the aluminum foil gas sampling bag 6 through the pipeline.

[0035] In this embodiment, during the adsorbent regeneration operation, the adsorption performance of the calcium oxide adsorption layer is detected through an on-line monitoring device or regularly. When the calcium oxide adsorption capacity reaches 80% saturation, start the switching process. Disassemble the device according to the process, disassemble the connection part between the current adsorption unit and the reaction cavity, install the standby adsorption unit, and switch the reaction gas to the standby adsorption unit for carbon dioxide adsorption. Take out the saturated calcium oxide adsorption layer and put it into a high-temperature calcination furnace. Calcinate it at a temperature of about 800 °C for about 2 hours to desorb the adsorbed carbon dioxide and realize the regeneration of the adsorbent. After the regenerated calcium oxide adsorption layer is cooled, reinstall it into the device and enter the next cycle of use, effectively reducing the operation cost and improving the sustainability of the device.

[0036] According to another aspect of the present invention, there is provided a test method using the above-mentioned waste plastic pyrolysis-reforming reaction device, including the following steps: S1. Equipment installation and debugging: Place the waste plastic pyrolysis device on a stable test bench, connect the pipelines and circuits between the components, check the operation of the equipment, and debug the parameters of each equipment to the initial state; S2. Atmosphere replacement and preheating: Open the valve of the inert gas cylinder 13, control the inert gas to flow into the reaction cavity at a flow rate of 500 mL / min for 15 minutes to evacuate the air with a flowmeter, and then adjust the flow rate to 50 mL / min; then start the electromagnetic induction heating device 3 and the spring heating coil temperature controller 2, and let the copper crucible 9 heat up to 300 °C at a rate of 5 °C / min according to the heating program, keep it at a constant temperature for 15 minutes to preheat the reaction cavity, and start the steam generator to inject steam after the preheating is completed; S3. Feedstock and Reaction: Continuously input waste plastic particles 8 into the reaction chamber through the automatic feeder 1 at a feeding rate of 0.1 g / h. During the reaction process, closely monitor the temperature data of each temperature control thermocouple and control the temperatures of the first and second-step reactions to maintain at the pre-determined test temperatures.

[0037] S4. Product Collection and Monitoring: After the pyrolysis gas adsorbs CO2 through the calcium oxide cake-shaped adsorption layer 12, it flows into the conical flask 5 filled with silica gel desiccant through the connecting pipe for drying, and then is introduced into the aluminum foil gas sampling bag 6 for collection. Finally, conduct gas chromatography component analysis on the collected synthesis gas and record each component and its content.

[0038] S5. End of Reaction: When the pre-determined reaction time ends, stop the feeding of the automatic feeder 1. Continue to maintain the operation of the electromagnetic induction heating device 3 and the spring heating coil temperature controller 2 to ensure that the remaining materials in the reaction chamber react 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 waiting for the reaction chamber to cool down to room temperature, disassemble each component and the experiment ends.

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

[0040] In the above introduction, the controllers, sensors, control programs, etc. that may be involved are all prior arts and will not be elaborated here.

[0041] The embodiments of the present invention disclosed above are only used to help illustrate the present invention. The embodiments do not describe all details in detail, nor limit the invention to the specific embodiments described. According to the content of this specification, many modifications and changes can be made. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention.

Claims

1. A waste plastic catalytic reforming device, characterized in that, The device includes: A glass tube reactor (4) with a copper crucible (9) inside for accommodating heated waste plastic particles (8); A catalytic-adsorption assembly, including: A steel wool catalyst (11) filled below the copper crucible (9) in the glass tube, whose three-dimensional network structure provides catalytic active sites; A calcium oxide cake-shaped adsorption layer (12) pressed and fixed below the steel wool catalyst (11) for adsorbing the carbon dioxide generated by the reaction; A spring heating coil (10) wound coaxially outside the copper crucible (9); An electromagnetic induction heating device (3) whose heating coil is arranged around the glass tube reactor (4) to heat the steel wool catalyst (11) through eddy current; Together with the spring heating coil (10), it constitutes a composite heating system; An automatic feeder (1) connected to the inlet end of the glass tube reactor (4) for continuously transporting waste plastic particles (8) to the copper crucible (9); An inert gas cylinder (13) connected to the glass tube reactor (4) through a pipeline for providing inert gas to the reaction system; A product collection unit, including: A conical flask (5) filled with silica gel desiccant, connected to the outlet of the glass tube reactor (4) for drying the syngas; An aluminum foil gas sampling bag (6) connected in series with the conical flask (5) for storing the purified syngas.

2. The device according to claim 1, wherein: The gas inlet of the glass tube reactor (4) includes an independent first gas source and a second gas source, which are respectively connected to the glass tube reactor (4) through control valves, where: The first gas source is the inert gas cylinder (13), and its steam injection end is located between the copper crucible (9) and the steel wool catalyst (11); The second gas source is a steam generator, and its purge gas inlet (7) is located at the end of the glass tube reactor (4) near the automatic feeder (1).

3. The device according to claim 1, wherein: The spring heating coil (10) is made of a nickel-chromium alloy resistance wire wound into a spiral structure, whose heating power and heating temperature can be independently regulated, and cooperate with the electromagnetic induction heating device (3) to realize the gradient temperature zone control of the copper crucible (9) and the steel wool catalyst (11).

4. The device according to claim 1, wherein: The calcium oxide cake-shaped adsorption layer (12) is pressed and formed from CaO powder and kaolin binder in a mass ratio of 4:1, with a thickness of 10 mm, and through holes with a pore diameter of 1 mm and a density of 7 per square centimeter are evenly opened on the surface.

5. The device according to claim 1, wherein: The steel wool catalyst (11) is formed by modifying stainless steel wire with 15% hydrochloric acid etching for 45 min and high-temperature oxidation in a high-temperature furnace at 550 °C for 2.5 h. Its specific surface area is 85 - 120 m² / g, the porosity is 40% - 55%, and the surface is loaded with an iron oxide active layer.

6. The device according to claim 1, wherein: The water vapor synergistic unit conveys water vapor to the reaction cavity through the purge gas inlet (7); the water vapor synergistic unit is equipped with an electric heating type water vapor generator, the internal heating element thereof selects 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 silica gel tube with an inner diameter of 5 mm; the water vapor flows in smoothly from above the quartz tube at a flow rate of 10 ml / min, the purge gas inlet (7) is adjacent to the copper crucible, and the vertical distance is controlled at 7 cm.

7. A method for catalytic reforming of waste plastics using the device according to any one of claims 1-6, characterized in that: S1. Convey the waste plastic particles (8) to the copper crucible (9) through the 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), and control the reaction cavity to be heated to a predetermined temperature according to the set program; S3. Open the argon gas source of the inert gas cylinder (13), set the inlet gas flow rate to 50 ml / min, start the water vapor generator, and introduce water vapor at a flow rate of 10 ml / min. The gas generated by the pyrolysis of the waste plastic passes through the high-temperature steel wool catalyst (11) for catalytic reforming and the calcium oxide cake-shaped adsorption layer (12) to remove carbon dioxide in sequence; S4. After the syngas discharged from the reaction cavity outlet removes water vapor through the conical flask (5) filled with drying silica gel, it is collected by the aluminum foil gas collection bag (6), and the unreacted solid residue remains in the steel wool catalyst (11).

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