Continuous cascade microwave treatment device for organic and inorganic composite materials

Abstract

The invention provides a continuous cascade microwave treatment device for organic and inorganic composite materials. The continuous cascade microwave treatment device comprises a feeding device, a furnace body reaction device, a discharging device, a gas circuit device and a monitoring control device. The feeding device adopts a pneumatic hammering type structure to realize continuous and controllable feeding of materials; a mode of combining multi-source microwave segmented heating and rake type stirring is adopted in the furnace body reaction device, efficient and uniform pyrolysis of materials is achieved, the inclination angle of a furnace body is adjusted through a lifting mechanism, and the material advancing speed and the reaction time are accurately controlled; the gas path device realizes energy circulation and temperature self-maintenance inside and outside the furnace through residual carbon oxidation and flue gas circulation processes, so that the energy consumption of the device is remarkably reduced, and the carbon capture efficiency is improved; the monitoring control device integrates temperature, flow, pressure and oxygen concentration monitoring and is provided with a pyrolysis gas combustion device. The equipment can be used for directly treating large-size blocky materials of 2-20cm, has both operation safety and recycling economy, and is suitable for resource recycling of composite materials such as wind power blades and the like.

Description

Technical Field

[0001] This invention relates to the fields of microwave heating equipment and composite material recycling technology, and in particular to a continuous cascade microwave treatment device for organic and inorganic composite materials. Background Technology

[0002] Microwaves generally refer to electromagnetic waves with frequencies between 0.3 and 300 GHz, with 2.45 GHz being commonly used in industry. Microwave pyrolysis is a novel pyrolysis method. Unlike traditional pyrolysis, microwave pyrolysis utilizes the response of specific components in the raw materials to microwaves, accelerating the vibration of microscopic particles and causing the temperature to rise from within the material. Therefore, in the microwave-triggered pyrolysis reaction, energy and mass transfer within the system proceed in the same direction, thereby enhancing the pyrolysis reaction and improving pyrolysis efficiency.

[0003] For most solid wastes, thermal treatment is an effective recycling method. However, currently used thermal treatment methods have some problems. For example, incineration easily produces harmful gaseous products, and conventional pyrolysis has low heating efficiency and causes significant damage to the inorganic components. Therefore, for the organic-inorganic composite material waste that has been generated in large quantities in recent years, conventional thermal treatment methods are not entirely suitable for its recycling. There is an urgent need to develop new thermal treatment devices and methods to meet the recycling needs of organic-inorganic composite materials. It is noted that the organic components of organic-inorganic composite materials usually have strong microwave absorption energy and good responsiveness to microwaves, making them very suitable for microwave pyrolysis for recycling. Current emerging organic solid wastes mainly include decommissioned wind turbine blades, photovoltaic panels, and batteries, all of which belong to organic-inorganic composite materials. Taking wind turbine blades as an example, their main components are glass fiber and epoxy resin. Epoxy resin can effectively absorb microwaves and heat up; therefore, developing microwave pyrolysis devices to recycle organic-inorganic composite materials, represented by wind turbine blades, is feasible.

[0004] Chinese utility model patent CN 221744057 U discloses an oxygen-enriched heat treatment system for efficiently recycling glass fibers from wind turbine blades, achieving fiber recycling through pyrolysis and low-temperature oxidation processes. However, this system uses traditional pyrolysis, which results in a long heat treatment process, high energy consumption, significant damage to the fibers, and difficulty in obtaining longer fibers. Chinese invention patent CN 114963183 A discloses a microwave pyrolysis system and method for treating wind turbine blades, but its proposed batch operation requires adding the wind turbine blades before the reaction begins and removing the glass fibers using a forklift after the reaction is complete, making continuous feeding and discharging impossible and hindering large-scale industrial applications. Chinese invention patent CN 120137689 A discloses a continuous displacement pyrolysis device and its pyrolysis method. Through a continuous displacement system including a pulley device, it achieves a continuous material flow path from feeding to microwave pyrolysis to tar cracking to discharging, effectively reducing microwave leakage and improving production efficiency. However, because the material needs to be crushed (particle size 0.5-15 mm) before feeding, the length and integrity of the glass fibers are damaged, which is not conducive to their recycling. Chinese invention patent CN 120137690 A discloses a system and method for microwave pyrolysis of large-size wind turbine blades with dual heat transfer modes. This method involves embedding ceramic sheets containing SiC microwave absorbers on the surface of a conveyor belt to perform microwave pyrolysis on large blades ranging from 1 to 3 meters in length. However, the durability and maintenance of the SiC ceramic sheets pose cost and safety issues. In practice, excessively large blades may experience uneven heating due to irregular shapes and varying thicknesses, leading to localized overheating and affecting subsequent fiber recycling. Chinese invention patent CN 114378099 A discloses a high-efficiency thermal delamination system and method for retired photovoltaic modules based on microwave pyrolysis. To increase the adaptability of the core components from room temperature to high temperature, three stages of pyrolysis reaction temperatures are set: 100℃-200℃, 300℃-400℃, and 550℃-650℃. However, the three microwave generators consume a lot of energy, seriously affecting energy conservation and carbon reduction. Chinese invention patent CN 110000189 A provides a high-efficiency resource recovery device for fiber-reinforced organic composite waste. It first performs microwave pyrolysis on the fiber-reinforced organic composite material, then introduces oxygen-containing gas to oxidize residual carbon, finally obtaining clean reinforcing fibers, pyrolysis oil, and combustible gas. This device is compact and simple to operate, but it cannot perform continuous feeding and discharging or large-scale industrial recycling, and the energy of the entire process depends entirely on external microwave input, resulting in poor economic efficiency.

[0005] In summary, there are still some problems with current large-scale disposal equipment for decommissioned organic-inorganic composite materials.

[0006] First, commonly used thermal treatment methods such as incineration and pyrolysis can cause significant damage to recycled fibers, and are also energy-intensive and highly polluting.

[0007] Industrial-scale composite material recycling equipment has high requirements for recycling efficiency. At the same time, considering economic and environmental benefits, continuous reaction equipment is very necessary. However, most of the current large-scale continuous equipment uses powder feeding. However, finer particles are not conducive to the accurate prediction and control of the sample movement trajectory during the reaction process. At the same time, powder may explode at high temperatures, which is not conducive to industrial safety.

[0008] In addition, for composite materials containing inorganic fibers, such as wind turbine blades, excessively small feed sizes can damage the length and integrity of the fibers, severely reducing their recycling value. Summary of the Invention

[0009] To address the shortcomings and deficiencies of existing composite material recycling technologies, a continuous cascade microwave processing device for organic and inorganic composite materials is provided. This device fundamentally solves the problems of fiber damage, environmental pollution, and industrial safety associated with existing devices for continuous processing of large-sized composite materials. At the same time, it utilizes a self-sustaining temperature and self-circulating energy design to minimize the operating costs of the device.

[0010] This invention is achieved through the following technical solution:

[0011] Compared with the prior art, the continuous stepwise microwave treatment device for organic-inorganic composite materials provided by the present invention has the following advantages:

[0012] (1) Direct and continuous feeding of large-sized block materials: The combined design of the feed hopper, transition chamber and pneumatic hammer allows for the feeding of block materials of 2-20 cm. This avoids the pre-treatment step of crushing the material into powder, which can protect the structural integrity of inorganic fibers in composite materials and greatly improve the utilization value of recycled fibers; at the same time, it eliminates the risk of dust explosion that may occur during the high-temperature pyrolysis of fine particulate materials and improves the safety of industrial operation.

[0013] (2) Utilizing the inherent properties of materials to achieve efficient internal heating: The organic components in organic-inorganic composite materials (such as the resin in wind turbine blades) act as natural microwave absorbing media, and the organic parts in organic-inorganic composite materials are excellent microwave absorbers. They can be heated in microwaves, and the heat diffuses from the inside of the material to the outside, which is consistent with the direction of heat transfer of reaction products. Heat transfer and mass transfer are mutually enhanced, reducing energy consumption during pyrolysis. It can efficiently absorb microwave energy and convert it into thermal energy. The heat is generated from the inside of the material and diffuses outward. Its transfer direction is the same as the direction of volatiles generated by pyrolysis escaping outward, forming a synergistic enhancement effect of heat transfer and mass transfer processes. This significantly reduces the time and energy loss required for heat conduction from the outside to the inside, and improves the pyrolysis reaction rate and energy utilization efficiency.

[0014] (3) Zonal Layout and Gradient Power Microwave Source Design: The six microwave sources are set up in a segmented frequency conversion configuration with decreasing microwave power from front to back. The front end of the six microwave sources is 100-1500 W, the back end is 100-600 W, and the middle two are set with decreasing frequency conversion between the front and back ends. The high-power microwave at the front end quickly starts pyrolysis, while the low-power or intermittent operation at the back end is only used to maintain the temperature. The tiered power supply mode matches the energy requirements of the material at different pyrolysis stages, avoids energy waste, and effectively reduces the overall microwave energy consumption of the system.

[0015] (4) Coordinated control of continuous cascade microwave processing and material conveying: The gravity sliding speed of the material in the reactor is controlled by adjusting the furnace body tilt angle through a lift. The lift adjusts the furnace body tilt angle to 0-10°, preferably 0-5°, to ensure a moderate material forward speed. The lift is located at the front of the furnace body support frame, and the tilt angle of the furnace body support frame is changed by varying the length of the lifting column. Combined with the rotation of the stirring rod, this achieves uniform and controllable continuous movement of the material from feed to discharge. This allows for precise control of the reaction time, meeting the requirements of pyrolysis kinetics for different materials, realizing continuous industrial processing, and significantly improving processing efficiency. The angle can be adjusted by the lift to tilt the reactor, facilitating control of the material forward speed and pyrolysis reaction rate.

[0016] (5) Built-in stirring to prevent uneven heating: A rotating stirring rod with stirring blades runs through the furnace body, continuously turning the material to ensure it is evenly exposed to the microwave field and hot atmosphere. The stirring speed is 0.2-10 r / min, preferably 2-3 r / min, to prevent excessive speed from causing centrifugal effect or severe dust generation that could trigger microwave discharge. This solves the problem of local overheating or insufficient heating caused by differences in material shape and thickness, ensuring the uniformity and thoroughness of pyrolysis, while preventing the material from sticking and clumping at high temperatures, thus ensuring smooth discharge.

[0017] (6) In-situ oxidation of residual carbon achieves self-sustaining temperature in the downstream section of the reactor: This exothermic oxidation process provides continuous heat to the downstream section of the furnace, reducing the dependence of this area on microwave energy, achieving self-sustaining temperature of the system, and further reducing operating energy consumption. The oxidation reaction can effectively remove residual carbon adhering to the surface of inorganic fibers, improving the cleanliness of the recovered fibers. Air is introduced from the bottom of the furnace to facilitate reaction with the solid, while nitrogen is introduced from the top of the furnace to ensure the oxygen-deficient pyrolysis environment of the furnace together with the gas generated after residual carbon oxidation. At the same time, the flue gas circulation and residual carbon oxidation process promote the enrichment of carbon dioxide, which facilitates subsequent tail gas treatment and carbon capture. By ensuring the self-sufficiency of heat at the downstream end of the reactor through flue gas circulation and residual carbon oxidation process, microwave energy consumption is further reduced, and carbon dioxide is enriched, thus improving both economic efficiency and environmental protection.

[0018] (7) Flue gas recirculation and deep utilization of waste heat: After the high-temperature flue gas is discharged from the exhaust port, it is fed into an external burner for combustion. The flue gas after combustion flows from the rear end to the front end of the furnace body along the flue pipe installed in the furnace, heating the furnace wall and internal gases along the way, and finally being ejected from the tail gas discharge port. The flue gas recirculation design recovers the sensible heat and chemical energy in the tail gas, providing an additional heat source for the material preheating zone in the front section of the furnace body, reducing dependence on external energy. It allows the gas to return to the furnace body to provide heat; it also enriches carbon dioxide, increasing its concentration and facilitating carbon capture.

[0019] (8) Precise Zoning Control of Oxygen-Deficient Environment and Atmosphere: A covering layer is formed by continuously introducing nitrogen gas at a flow rate of 100-200 mL / min from above (the function of 16), combined with the controllable air flow rate of 50-200 mL / min from below, and monitored by an oxygen analyzer, establishing a stable and adjustable oxygen-deficient pyrolysis atmosphere in the furnace. The pressure gauge threshold is recommended to be set below 0.6 MPa, and the oxygen concentration measured by the oxygen analyzer must be stable below 2%. If the pressure exceeds 0.8 MPa and the oxygen concentration exceeds 3%, the microwave leakage detection alarm will be triggered, and the power will be cut off. This effectively inhibits the excessive combustion of organic materials at high temperatures or the generation of harmful fumes, ensuring a gentle and controllable pyrolysis process, avoiding violent combustion, and protecting inorganic fibers from oxidative damage.

[0020] (9) Microwave source and reaction chamber isolation and anti-fouling: The raised cavity is located in the middle section of the upper surface of the furnace body. The raised cavity is separated from the furnace body by a transparent quartz heat insulation and anti-fouling plate. The transparent quartz plate can efficiently transmit microwaves and physically isolate the microwave generator from the reaction chamber where dust may be generated. This prevents contaminants from adhering to the microwave source window, prevents materials inside the furnace from interfering with the use of the microwave source, ensures the long-term stability of microwave transmission efficiency, reduces equipment maintenance frequency and cost, and improves the reliability and durability of the system.

[0021] (10) Comprehensive safety protection and intelligent monitoring: Microwave leakage detection and alarm devices, automatic shutdown devices, pressure gauges, thermocouples, and control computers constitute a multi-layered safety protection system. The entire system can monitor and prevent microwave leakage in real time, monitor the pressure inside the furnace to avoid the risk of overpressure, detect the oxygen concentration inside the furnace to prevent combustion or explosion, and achieve precise temperature control through multi-point temperature measurement. All key parameters (microwave power, gas flow rate, temperature, etc.) can be centrally controlled and linked by the computer. This greatly improves the automation, safety, and stability of the device operation, meeting the requirements of industrial production. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the main structure of the continuous cascade microwave treatment device of the present invention;

[0023] Figure 2This is a side cross-sectional schematic diagram of the continuous stepped microwave treatment device of the present invention;

[0024] a is a cross-sectional view including the microwave source, and b is a cross-sectional view including the flue pipe.

[0025] Figure 3 This is a schematic diagram of the gas flow direction in the residual carbon oxidation process of step 6 of the present invention;

[0026] Figure 4 This is a schematic diagram of the gas flow direction in the flue gas recirculation process of step 7 of the present invention;

[0027] In the diagram: 1-Feed hopper, 2-Transition bin, 3-Pneumatic hammer, 4-Flange, 5-Furnace body, 6-Microwave source, 7-Stirring rod, 8-Elevator, 9-Quartz heat insulation and anti-fouling plate, 10-Furnace body support frame, 11-Motor, 12-Lifting column, 13-Discharge port, 14-Collection tank, 15-Discharge valve, 16-Nitrogen inlet, 17-Air inlet, 18-Flue pipe, 19-Exhaust port, 20-Oxygen analyzer, 21-Flow meter, 22-Pressure gauge, 23-Thermocouple, 24-External burner, 25-Tail exhaust port. Detailed Implementation

[0028] This invention discloses a continuous stepped microwave treatment device for organic-inorganic composite materials. The technical solution of this invention will be further described below with reference to the accompanying drawings and specific embodiments:

[0029] Figure 1 This is a schematic diagram of the main structure of the continuous cascade microwave treatment device of the present invention; Figure 2 This is a side cross-sectional view of the continuous cascade microwave treatment device of the present invention; a is a cross-sectional view including the microwave source, and b is a cross-sectional view including the flue pipe. Figure 3 This is a schematic diagram of the gas flow direction in the residual carbon oxidation process of step 6 of the present invention; Figure 4 This is a schematic diagram of the gas flow direction in the flue gas circulation process of step 7 of the present invention.

[0030] This invention discloses a continuous stepped microwave processing device for organic-inorganic composite materials, comprising a furnace body 5 reaction device, a feeding device connected to the furnace body 5 reaction device, a discharging device, a support tilting drive device located at the bottom of the furnace body 5 reaction device near the feeding device, and a gas passage device disposed on the furnace body 5 reaction device; the furnace body 5 reaction device includes a furnace body 5, a protruding cavity 26 located on the upper surface of the furnace body 5, a stirring rod 7 located inside the furnace body 5 and fixed on the central axis of the furnace body 5, and a microwave source 6 with a window disposed in the protruding cavity 26. The microwave source 6 is located within the furnace body 5. The tilting drive device includes a furnace body support frame 10 located below the furnace body 5, a lifting column 12 fixedly connected to the surface of the furnace body support frame 10, and a lifting machine 8. The lifting machine 8 is located near the front section of the furnace body 5. The gas path device includes a nitrogen inlet 16 located on the upper part of the rear end wall of the furnace body 5, an air inlet 17 located on the wall of the furnace body 5 near the middle and rear section, a tail gas exhaust port 25 located on the upper surface of the furnace body 5, and an exhaust port 19 located on the wall of the furnace body 5 near the upper part and connected to the tail gas exhaust port 25. The nitrogen inlet 16 is located at the upper end of the furnace body 5, the air inlet 17 is located on the lower right side of the middle and rear section of the furnace body 5, and the exhaust port 19 is located directly above the furnace body 5.

[0031] The feeding device includes a feed hopper 1 located at the front of the upper surface of the furnace body 5, extending from top to bottom; a transition chamber 2; a pneumatic hammer 3 installed on the side wall of the transition chamber 2; and a feed inlet connected to the transition chamber 2 via pipeline. The material entering the feed hopper 1 is 2-20cm in size and does not need to be crushed into powder. The feed hopper 1 and the transition chamber 2 are supported and connected by a flange 4, and the pneumatic hammer 3 is connected to the side of the transition chamber 2 via a small flange. The transition chamber 2 has an opening at the bottom; material is discharged by adjusting the opening size. The feed inlet is only for feeding, and the material is temporarily stored in the transition chamber 2. When the opening of the transition chamber 2 is blocked, the pneumatic hammer 3 strikes the transition chamber 2, causing the material to continue falling into the furnace body 5 through the opening.

[0032] The discharge device includes a discharge port 13 located at the rear of the lower surface of the furnace body 5, extending from top to bottom; a discharge tank connected to the discharge port 13 via a pipeline; and a discharge valve 15 installed on the discharge port 13 pipeline. The discharge is controlled by the size of the valve.

[0033] The inner wall of the furnace body 5 is made of high-temperature resistant quartz, and the outer wall is made of microwave-insulating metal. The stirring rod 7 is connected to a motor, and at least three stirring blades are evenly distributed on the stirring rod 7. In this embodiment, the stirring rod 7 includes seven stirring blades evenly distributed on the stirring rod 7, and the stirring rod 7 is driven to rotate by the motor 11.

[0034] The protruding cavity 26 is located in the middle section of the upper surface of the furnace body 5. A transparent quartz heat-insulating and anti-fouling plate 9 separates the protruding cavity 26 from the furnace body 5. The transparent surface of the quartz heat-insulating and anti-fouling plate 9 separates the microwave source 6 from the furnace cavity, preventing materials inside the furnace body 5 from interfering with the use of the microwave source 6. The microwave source 6 consists of at least two groups of microwave sources located on the same plane perpendicular to the furnace body 5. Each group includes two sources at the top and one on each side. The window of each microwave source 6 faces the protruding cavity and is located inside the protruding cavity. There are a total of sixteen microwave sources 6, located above and to the sides of the protruding part in the middle of the furnace body 5. The eight microwave sources at the top are arranged in four vertical rows side by side.

[0035] The six microwave sources feature a segmented frequency conversion setting with decreasing microwave power from front to back. The front of the six microwave sources has a power range of 100-1500 W, while the rear has 100-600 W. The two middle sources show a decreasing frequency conversion between the front and rear values. The power of the six microwave sources gradually decreases from the front to the rear of the furnace body 5, enabling segmented frequency conversion. This ensures that the microwave heating in the front section of the furnace and the temperature in the rear section are self-sustaining. In addition, the operating time of the magnetron in each microwave source 6 can be adjusted individually, thereby releasing microwaves intermittently and reducing the system's microwave energy consumption.

[0036] The lifting platform 8 adjusts the tilt angle of the furnace body 5 to 0-10°. The lifting platform 8 is located at the front of the furnace body support frame 10. The furnace body support frame 10 includes a horizontal support frame and three vertical support frames connected to it. The tilt angle of the furnace body support frame 10 is changed by the change in the length of the lifting column 12. The stirring speed of the stirring rod 7 is 0.2-10 r / min. The flue pipe 18 connected to the exhaust port 19 includes an outer part of the furnace body 5 and an inner part of the furnace body 5. The flue pipe 18 of the outer part of the furnace body 5 is equipped with an external burner 24. The inner part of the furnace body 5 is located on the inner wall of the upper surface of the furnace body 5 cavity.

[0037] The preferred tilt angle of the furnace body 5 is 0-5° for the elevator 8, and the preferred rotation speed of the stirring rod 7 is 2-3 r / min.

[0038] It also includes a hot-wire thermocouple installed on the wall of furnace body 5, offset from the plane of the stirring blades; a flow meter 21, independent of furnace body 5 and connected to the inlet pipes of nitrogen inlet 16 and air inlet 17, i.e., nitrogen first passes through flow meter 21 and then through nitrogen inlet 16, and air first passes through flow meter 21 and then through air inlet 17; an oxygen analyzer 20 located on the front wall of furnace body 5; a pressure gauge 22 located on the upper surface of furnace body 5; and a microwave leakage detection alarm device set near the feed inlet and discharge outlet 13. The automatic shutdown device is controlled by feedback from the control system to ensure operational safety. All of the above components are connected to an external control computer circuit. The pneumatic hammer 3, microwave source 6, stirring rod 7, and elevator 8 are also connected to the external control computer circuit. The start and stop of microwave source 6, oxygen analyzer 20, and flow meter 21 are synchronized with the start and stop of the entire microwave device. The oxygen analyzer 20 is located at the upper front of the furnace body 5, and the pressure gauge 22 is located above the rear section of the furnace body 5. It is used to detect the gas pressure inside the furnace. Thermocouples 23 are evenly distributed in the front, middle and rear of the furnace to measure the temperature of the material at different travel positions. The external burner 24 is located after the exhaust port 19 and can burn the discharged high-temperature pyrolysis flue gas. Then the gas continues to enter the upper part of the furnace along the pipeline and is discharged from the tail gas exhaust port 25 at the front of the furnace body 5.

[0039] The pneumatic hammer 3, microwave source 6, stirring rod 7, elevator 8, oxygen analyzer 20, and flow meter 21 can all be started and stopped and their parameters adjusted in a control computer independent of the furnace body 5. The start and stop of the microwave source 6, oxygen analyzer 20, and flow meter 21 are synchronized with the start and stop of the entire microwave device.

[0040] The method of using this device is as follows:

[0041] Step 1), connect the gas pipeline and check the airtightness, adjust the nitrogen flow meter 21 to 100-200 mL / min, and introduce nitrogen from the nitrogen inlet 16 for 20-60 minutes to ensure that the air in the system is completely discharged, and continue to introduce nitrogen during the reaction process.

[0042] Step 2), the threshold value of pressure gauge 22 is recommended to be set below 0.6 MPa. The oxygen concentration measured by oxygen analyzer 20 should be stable below 2%. When the pressure exceeds 0.8 MPa and the oxygen value exceeds 3%, the microwave leakage detection alarm device will be activated and the power will be cut off.

[0043] Step 3), adjust the elevator 8 so that the furnace body 5 tilts at 0-5°, and adjust the motor control stirring rod 7 to rotate at 2-3 r / min;

[0044] Step 4) Set the microwave pyrolysis reaction temperature to 300-1000 ℃. Each microwave source 6 is equipped with circulating cooling water. The external cooling water pump outside the furnace is turned on by the control computer to prevent the microwave source 6 from failing due to overheating. Then, the microwave source 6 is turned on. During the initial setup, the power of the four microwave sources 6 in the first row on the left is set to 100-1500 W, the power of the four microwave sources 6 in the fourth row on the far right is set to 100-600 W, and the power of the two middle rows is set as follows: the maximum power is between 600-1400 W, and the power of the second row of microwave sources 6 is greater than that of the third row, and the minimum power is 100 W. During the reaction, the thermocouple 23 will feed back the measured temperature to the computer, and the microwave power will be automatically adjusted according to the temperature fed back by the thermocouple 23: when the temperature is higher than the set temperature, the power decreases, and vice versa.

[0045] Step 5), put the 2-20 cm material into the feed hopper 1, and use the pneumatic hammer 3 to strike the transition chamber 2 to deliver the material;

[0046] Step 6): The material undergoes microwave pyrolysis inside the furnace body 5, and the generated high-temperature pyrolysis flue gas is discharged from the exhaust port 19;

[0047] Step 7), Residual Carbon Oxidation: After a period of reaction, adjust the air flow meter 21 to 50-200 mL / min, and introduce air through the air inlet 17, forming a counter-current airflow with the sample's direction of travel. At the high temperature inside the furnace, the pyrolysis residual carbon generated in the rear section of furnace 5 is oxidized. At this time, the reaction produces complete combustion products such as carbon dioxide. These high-temperature combustion gaseous products continue to flow along the airflow direction towards the front middle of the reactor, finally forming high-temperature combustion flue gas that is discharged from the exhaust port 19. The introduced air flows in the opposite direction to the sample's direction of travel, oxidizing the pyrolysis residual carbon at the high temperature inside furnace 5. The heat released by the oxidation reaction simultaneously ensures the self-sustaining temperature inside the furnace. The reaction gas flows towards the front of the furnace and heats the front chamber, then cools down to a medium-high temperature gas before being discharged from furnace 5. Air is introduced from the bottom of furnace 5 to facilitate reaction with the solid, while nitrogen is introduced from the top of furnace 5, together with the gas produced after residual carbon oxidation, ensuring an oxygen-deficient pyrolysis environment in the furnace.

[0048] Step 8), flue gas recirculation: The high-temperature pyrolysis flue gas generated in Step 6) and the high-temperature combustion flue gas generated in Step 7) are discharged from the exhaust port 19 and then fed into the external burner 24 for combustion. The flue gas after combustion flows from the rear end of the furnace body 5 to the front end along the flue pipe 18 installed in the furnace. The process of returning to the furnace is equivalent to flue gas recirculation. After heating the gas in the furnace, it is sprayed out from the tail gas discharge port 25. Its own temperature is reduced to medium and high temperature, which can serve as a heat source to ensure the temperature in the furnace is self-maintained, and at the same time facilitates subsequent carbon capture. The carbon dioxide and residual carbon generated in Step 7) can further react to generate carbon monoxide, which is then burned in Step 8). This leads to the enrichment of carbon dioxide, which facilitates carbon capture of the last discharged gas.

[0049] (Step 9) The solid product after the reaction is discharged through the discharge port 13, with the discharge valve 15 acting as a control switch, and finally collected in the receiving tank 14.

[0050] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any modifications or equivalent substitutions made to the present invention without departing from the spirit and scope thereof should be covered within the protection scope of the claims of the present invention.

Claims

1. A continuous stepped microwave treatment device for organic-inorganic composite materials, characterized in that, The system includes a furnace reaction device, a feeding device connected to the furnace reaction device, a discharging device, a support tilting drive device located at the bottom of the furnace reaction device near the feeding device, and a gas path device installed on the furnace reaction device. The furnace reaction device includes a furnace body, a raised cavity located on the upper surface of the furnace body, a stirring rod located inside the furnace body and fixed on the central axis of the furnace body, and a microwave source with a microwave source window located in the raised cavity. The support tilting drive device includes a furnace body support frame installed below the furnace body, a lifting column and a lifting machine fixedly connected to the surface of the furnace body support frame, with the lifting machine located near the front section of the furnace body. The gas path device includes a nitrogen inlet located on the upper part of the rear wall of the furnace body, an air inlet located on the furnace body wall near the middle and rear section, a tail gas exhaust port located on the upper surface of the furnace body, and an exhaust port located on the upper part of the furnace body arm connected to the tail gas exhaust port.

2. The continuous stepped microwave treatment device for organic-inorganic composite materials according to claim 1, characterized in that, The feeding device includes a feeding hopper located at the front of the upper surface of the furnace body, a transition chamber, a pneumatic hammer set on the side wall of the transition chamber, and a feeding port connected to the pipeline of the transition chamber. The material entering the feeding hopper is blocky material with a size of 2cm-20cm.

3. The continuous stepped microwave treatment device for organic-inorganic composite materials according to claim 2, characterized in that, The discharge device includes a discharge port located at the rear section of the lower surface of the furnace body, extending from top to bottom, a discharge tank connected to the discharge port pipeline, and a discharge valve installed on the discharge port pipeline.

4. The continuous stepped microwave treatment device for organic-inorganic composite materials according to claim 3, characterized in that, The inner wall of the furnace body is made of high-temperature resistant quartz, and the outer wall is made of microwave-insulating metal. The stirring rod is connected to a motor, and at least three stirring blades are evenly distributed on the stirring rod.

5. The continuous stepped microwave treatment apparatus for organic-inorganic composite materials according to claim 1, 2, 3, or 4, characterized in that, The protruding cavity is located in the middle section of the upper surface of the furnace body. The protruding cavity is separated from the furnace body by a transparent quartz heat insulation and anti-fouling plate. The microwave source consists of at least two groups of microwave sources located on the same plane perpendicular to the furnace body. Each group includes two sources at the top and one source on each side. The window of each microwave source faces the protruding cavity and is located inside the protruding cavity.

6. The continuous stepped microwave treatment device for organic-inorganic composite materials according to claim 5, characterized in that, The microwave source group is a segmented frequency conversion setting with a decreasing microwave power gradient from the front to the back. The front end of the microwave source group is 100-1500W and the back end is 100-600W. The two middle ones are set with decreasing frequency conversion between the front and back ends.

7. The continuous stepped microwave treatment device for organic-inorganic composite materials according to claim 6, characterized in that, The lifting mechanism adjusts the furnace body tilt angle to 0-10°, the stirring rod rotation speed is 0.2-10 r / min, and the flue pipe connected to the exhaust port includes an external part and an internal part. The external part of the flue pipe is equipped with an external burner, and the internal part is located on the inner wall of the furnace body cavity, near the upper surface.

8. The continuous stepped microwave treatment device for organic-inorganic composite materials according to claim 7, characterized in that, The preferred tilt angle of the furnace body is 0-5°, and the preferred rotation speed of the stirring rod is 2-3 r / min.

9. The continuous stepped microwave treatment apparatus for organic-inorganic composite materials according to any one of claims 1, 2, 3, 4, 6, 7, or 8, characterized in that, It also includes a hot spot thermocouple installed on the furnace wall and offset from the plane of the stirring blades, a flow meter installed on the air inlet pipes connected to the furnace wall, an oxygen analyzer located on the front section of the furnace wall, a pressure gauge located on the upper surface of the furnace, and a microwave leakage detection alarm device installed near the feed inlet and discharge outlet. All of the above components are connected to an external control computer circuit. The pneumatic hammer, microwave source, stirring rod, and elevator are also connected to an external control computer circuit. The start and stop of the microwave source, oxygen analyzer, and flow meter are synchronized with the start and stop of the entire microwave device.

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