Preparation system for continuously producing carbon nanotube reinforced resin-based composite material

Abstract

The invention discloses a preparation system for continuously producing a carbon nanotube reinforced resin-based composite material, and relates to the technical field of functional composite material preparation, the system comprises a first fluidized bed reactor and a second fluidized bed reactor which are connected in series through a gas circuit, the bottom of the second fluidized bed is connected with a carbon nano tube conveying pipe communicated with the first fluidized bed, the bottom of the first fluidized bed is connected with a carbon nano tube discharging pipe, the carbon nano tube discharging pipe is connected with a mixer, the mixer is connected with a plurality of feeding pipelines, the inside of the mixer is connected with a porous distribution plate, and a discharging port in the bottom of the mixer is connected with a rotary feeder. The rotary feeder is connected with the Venturi tube, and the Venturi tube is connected with the shearing structure; the shearing structure is connected with the melting structure which is connected with the air pressure former, and the rear end of the air pressure former is connected with the nitrogen cooler. According to the system, the technical problems of reinforced phase nanoscale dispersion and material densification are solved, the production efficiency and the product quality stability of the carbon nanotube reinforced resin-based composite material are improved, and the production cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of functional composite material preparation technology, and specifically to a preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials. Background Technology

[0002] Continuous production technology for resin-based composite materials is widely used in electronic packaging, automotive manufacturing, and consumer electronics. The use of conductive and thermally conductive plastics in electronic components is growing at an average annual rate of over 25%, but the performance stability and production efficiency of existing materials urgently need improvement. To achieve large-scale automated production and improve product consistency, in-depth research into continuous production technology is crucial for the transformation and upgrading of my country's plastics industry. In recent years, the technological development and industrial application of continuous production of functionalized resin-based composite materials have continued to heat up.

[0003] Continuous production of resin-based composite materials, as an advanced automated production process, offers significant advantages for applications requiring high efficiency and high quality. Traditional resin-based composite material production mainly consists of three stages: raw material pretreatment, melt blending, and product molding.

[0004] While continuous production technology has broad prospects, its engineering applications still face limitations. Traditional production methods restrict material handling and process control, making precise control throughout the entire process difficult. Furthermore, online monitoring and quality control remain technical challenges. Optimizing production line design and control systems can enable precise adjustment of process parameters, which helps ensure product quality stability. Currently, in industrial applications, production lines mostly adopt segmented control modes. This approach limits overall efficiency, as the production process relies on independent adjustments of each unit, making coordinated control of the entire process difficult and lacking flexibility in process adjustment, which is detrimental to flexible production of multiple product varieties. In traditional production modes, parameters of each section influence each other, and the high coupling of quality control links leads to long product specification adjustment cycles, restricting the application benefits of this technology in multi-variety, small-batch production scenarios.

[0005] In existing research, Zhang et al. (Composites Science and Technology, 2022, 218:109-118) developed a fluidized bed-based method for preparing carbon nanotube / polymer composites, achieving dispersion of the reinforcing phase with airflow assistance. However, this method suffers from problems such as unstable material transport and easy agglomeration of carbon nanotubes in continuous production, affecting the consistency of product performance.

[0006] Therefore, current resin-based composite materials still face the problem of carbon nanotubes easily agglomerating and being difficult to disperse at the nanoscale during the production process. At the same time, there is also the problem of insufficient ability to simultaneously control material densification and functionalization, which affects product consistency and production efficiency. Summary of the Invention

[0007] Given the current challenges in producing resin-based composite materials, such as the tendency for carbon nanotubes to agglomerate and the difficulty in achieving nanoscale dispersion, this invention aims to provide a continuous production system for carbon nanotube-reinforced resin-based composite materials. This system achieves efficient conversion of carbon dioxide to carbon nanotubes through a two-stage fluidized bed reactor, employs a composite reactor and Venturi tube conveying structure to achieve precise proportioning and efficient transport of each component, solves the technical difficulties of nanoscale dispersion of the reinforcing phase and material densification through a two-stage melt blending and gas-assisted molding process, and significantly improves production efficiency and product quality stability through a full-process control system.

[0008] This invention is achieved through the following technical solution:

[0009] This application provides a continuous production system for carbon nanotube-reinforced resin-based composite materials, comprising a first fluidized bed reactor and a second fluidized bed reactor connected in series via gas paths. The bottom of the second fluidized bed reactor is connected to a carbon nanotube delivery pipe communicating with the first fluidized bed reactor. The bottom of the first fluidized bed reactor is connected to a carbon nanotube discharge pipe, which is connected to a mixer. The mixer has multiple feed pipes connected to it, and a porous distribution plate is connected inside. A rotary feeder is connected to the discharge port at the bottom of the mixer, which is connected to a venturi tube. The venturi tube is connected to a shearing structure. The shearing structure is connected to a melting structure, which is connected to a pressure forming device. The rear end of the pressure forming device is connected to a nitrogen cooler.

[0010] Among them, the air pressure forming device introduces an active atmosphere, and under the combined action of pressure and temperature, the final shaping of the material and the construction of the surface functional layer are completed simultaneously.

[0011] Heating structures can be connected to both the first and second fluidized bed reactors. These heating structures can employ resistance / electromagnetic heating systems to achieve selective growth of carbon nanotubes by controlling the reaction temperature (500℃~800℃), catalyst concentration, and gas flow rate. A molten salt heating system maintains the internal temperature of the reactor at the optimal reaction temperature.

[0012] In the preparation of carbon nanotube-reinforced resin-based composite materials, engineering resins are selected as the matrix material, specifically including polyetheretherketone (PEEK), polymers, and other high-molecular powders. Particle size range is controlled to ensure good flowability. Multi-walled carbon nanotubes serve as the main conductive and thermally conductive medium for the reinforcing phase. Each component is precisely proportioned through independent metering, with the resin matrix accounting for 60wt%~80wt%, carbon nanotubes for 5wt%~15wt%, and functional fillers for 10wt%~30wt%.

[0013] Furthermore, the shearing structure includes a first shearer connected to an ejector, the ejector connected to a second shearer, and the second shearer connected to the melting structure.

[0014] Furthermore, the melting structure includes a primary melter and a secondary melter connected in series. Both the primary and secondary melters are connected to a heat source replenishment structure. A material transport pipeline connecting the shearing structure and the melting structure is connected to a heating structure for the substance to be melted. The heating structure for the substance to be melted is a molten salt heating system.

[0015] Furthermore, the heat source supplementation structure includes a hot air duct connected to the primary melter and the secondary melter, the hot air duct is connected to a fan, and an air heating structure is connected to the hot air duct.

[0016] The air heating structure is a molten salt heating system. The temperature of the primary and secondary melters can be controlled by adjusting the fan speed to regulate the hot air flow. When the temperature in the melting zone deviates from the set value, the fan speed can be adjusted.

[0017] Furthermore, both the first and second fluidized bed reactors are connected to a product separation structure at the top; the outlet pipe of the product separation structure is connected to the catalyst inlet of the second fluidized bed reactor, and a first injector is connected to the outlet pipe; the first injector is connected to a power pipe, a power pump is connected to the power pipe, and the power pipe is connected to the carbon source inlet pipe of the first fluidized bed reactor; a hydrogen inlet pipe is connected to the bottom of the first fluidized bed reactor.

[0018] Furthermore, both the first fluidized bed reactor and the second fluidized bed reactor are equipped with a fixed reactor, and the fixed reactor is equipped with a porous gas distribution plate and a flow guide baffle connected to the top of the fixed reactor.

[0019] Furthermore, the outlet end of the product separation structure on the second fluidized bed reactor is connected to an exhaust pipe, which is connected to a catalyst recovery device and a hydrogen recovery device.

[0020] Furthermore, the catalyst recovery device includes a second cyclone separator, the top outlet of which is connected to a hydrogen recovery device, and the bottom of which is connected to a catalyst reuse pipeline. The catalyst reuse pipeline is connected to two catalyst reuse branch pipes that are respectively connected to the first fluidized bed reactor and the second fluidized bed reactor via a tee connector.

[0021] Furthermore, the hydrogen recovery device includes a second injector connected to a membrane separation unit, which is connected to a pressure swing adsorption system.

[0022] The membrane separation unit employs a multi-stage membrane structure. The mixed gas generated during the reaction enters the membrane separation unit, where a hydrogen-rich permeate gas is separated. The remaining impermeable gas enters the pressure swing adsorption system, where high-purity hydrogen is further separated. The separated hydrogen is returned to the reaction system via a reuse pipeline to continue participating in the reaction. The use of multi-stage adsorption towers achieves continuous and efficient hydrogen recovery. The recovered hydrogen, after pressurization, is directly returned to the reactor for recycling. This structure replaces the traditional direct emission process, significantly reducing the consumption of raw material gases and improving the resource utilization efficiency and economy of the entire system.

[0023] Furthermore, the top of the pressure swing adsorption system is connected to a first hydrogen recycling pipe that is connected to the hydrogen inlet pipe of the first fluidized bed reactor; the bottom of the pressure swing adsorption system and the membrane separation unit is connected to a second hydrogen recycling pipe that is connected to the hydrogen inlet pipe of the second fluidized bed reactor.

[0024] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0025] (1) The system of the present invention achieves efficient conversion of carbon dioxide to carbon nanotubes through a two-stage fluidized bed reactor, and achieves precise proportioning and efficient transport of each component by using a composite reactor and Venturi tube transport structure. It solves the technical problems of nanoscale dispersion of reinforcing phase and densification of materials through two-stage melt blending and gas-assisted molding process, and significantly improves production efficiency and product quality stability through the whole process control system.

[0026] (2) The system of the present invention utilizes the porous distribution plate in the mixer to achieve static mixing. At the same time, it is combined with the Venturi tube to solve the pollution and energy consumption problems caused by traditional mechanical stirring. Meanwhile, the connected shear structure, melting structure and gas pressure forming device realize the synchronous optimization of the microstructure control of the material and the construction of the surface functional layer. It achieves uniform dispersion of the functional phase in the matrix and a significant improvement in the interfacial bonding strength. At the same time, through the perfect pipeline network, it realizes the fully enclosed transportation of materials and the precise control of process parameters, effectively improving the consistency and stability of product performance.

[0027] (3) By connecting the Venturi tube, the present invention replaces the traditional mechanical conveying method with the Venturi effect generated by the Venturi tube. It not only realizes the precise conveying and proportion control of various functional materials, but also ensures the performance stability of functional materials during the transmission process through a unique sealed conveying mechanism, especially avoiding the performance degradation of easily oxidized materials such as boron carbide during the transmission process.

[0028] (4) By connecting the air pressure forming device, the present invention can controllably generate a dense oxide alloy protective layer on the material surface by introducing a hot air flow of specific components into the atmosphere pressure furnace during the air pressure shaping stage. This design replaces the traditional surface treatment process by precisely controlling the hot air temperature, flow rate and oxygen partial pressure. It not only achieves the simultaneous completion of material densification and surface modification, but also significantly improves the surface hardness and oxidation resistance of the composite material through the metallurgical bonding between the oxide layer and the substrate.

[0029] (5) The melting structure of the present invention consists of two-stage melters connected in series, so that the carbonaceous product completes basic melting and homogenization in the first-stage melter, and then enters the second-stage melter for fine conditioning, thereby realizing the continuous and stable molding of carbon nanotube reinforced resin matrix composites, and at the same time obtaining carbon nanotube reinforced resin matrix composite products with ideal morphology and consistency.

[0030] (6) The molten structure of the present invention achieves precise control of the microstructure of carbon nanotube reinforced resin matrix composite products through the synergistic effect of hot air, thereby improving the quality of the prepared carbon nanotube reinforced resin matrix composite products.

[0031] (7) This invention realizes the stepwise catalytic conversion of mixed carbon sources through a two-stage fluidized bed reactor, and achieves efficient utilization of raw materials by using interstage separation and circulation units. It realizes the direct conversion of mixed carbon sources to carbon nanotubes, improves the conversion rate of mixed carbon sources, and also improves the quality of products. The process is simple, energy consumption is significantly reduced, and product performance is stable. The system is suitable for various working conditions from negative pressure to medium pressure, and provides a new technical path for the resource utilization of mixed carbon sources.

[0032] (8) In this invention, the first and second fluidized bed reactors connected in series can achieve continuous feeding. The first fluidized bed reactor achieves catalytic activation of the mixed carbon source to obtain carbon nanotubes and some intermediate products. The formed intermediate products enter the second fluidized bed reactor to continue the reaction and generate carbon nanotubes. The reaction is completed through continuous feeding and discharging. The gas-solid separation is achieved through the interstage separation structure, and the separated catalyst is returned to the reaction system for reuse.

[0033] (9) The fluidized bed reactor of the present invention is equipped with a porous gas distribution plate to ensure that the reaction gas is uniformly distributed in the bed. At the same time, the staggered flow guide plates inside the reactor can effectively prolong the gas-solid phase contact time and improve the raw material conversion efficiency. Meanwhile, the flow guide baffles enhance the airflow disturbance, enabling the reactants to diffuse rapidly to the catalyst active sites. This strong turbulent environment ensures high mass transfer efficiency, allowing the carbon source gas to be rapidly cracked and deposited, thereby achieving high-speed growth of carbon nanotubes.

[0034] (10) The hydrogen recovery device connected in this invention can perform membrane separation and pressure swing adsorption separation on unreacted gas and return it to the fluidized bed reactor for reuse, thereby improving the utilization rate of raw materials. Through the synergistic effect of dual reactors in series and raw material recycling, the product quality and production efficiency are significantly improved. It has the advantages of high conversion rate and good product consistency. Compared with the traditional single reactor, the process investment cost of this reactor is reduced by more than 40% and the energy consumption is reduced by more than 35% when it is applied, providing a reliable technical approach for the high-value utilization of mixed carbon sources.

[0035] (11) The ejector in this invention is the core power structure. It uses a high-pressure power gas source to generate a vacuum effect, providing stable gas flow power for the entire reaction system. The ejector ensures that the reactants form a stable sulfidation state in the fluidized bed reactor by precisely controlling the gas flow rate and pressure parameters, while realizing the efficient recycling of unreacted gas.

[0036] (12) The system in this invention is stable, energy-efficient, safe and reliable. It can process mixed carbon source raw materials of different concentrations. The system has wide raw material adaptability and high operational flexibility. It is suitable for various process conditions such as negative pressure, normal pressure, pressurization or vacuum. The preparation system is flexible in regulation and has high production efficiency.

[0037] (13) The continuous production system for carbon nanotube-reinforced conductive and thermally conductive resin-based composite materials of the present invention has broad application prospects. The system has a high degree of automation, low energy consumption, and significant production efficiency. This system is not only suitable for the field of electronic packaging materials, but can also be widely used in the production of functional composite materials in the fields of automotive parts and smart wearable devices. The system adopts a modular design, which can flexibly adjust the production process according to product specifications, and is suitable for large-scale continuous production needs. The innovative process flow of this system ensures the consistency and stability of product performance, and provides a complete technical guarantee for the industrial production of resin-based functional composite materials. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the structure of a continuous production system for carbon nanotube-reinforced resin-based composite materials according to the present invention.

[0040] Figure label:

[0041] 01-Hydrogen inlet pipe, 02-Heating structure, 03-First fluidized bed reactor, 04-Porous gas distribution plate, 05-Fixed reactor, 06-Baffle plate, 07-First cyclone separator, 08-First hydrogen recovery pipe, 09-Catalyst recovery pipe, 10-Second cyclone separator, 11-Hydrogen replenishment pipe, 12-Pressure swing adsorption system, 13-Secondary membrane separation unit, 14-First-stage membrane separation unit, 15-Second hydrogen recovery pipe, 16-Second ejector, 17-Second fluidized bed reactor, 18-First ejector 19-Power pump, 20-Power pipe, 21-Carbon source inlet pipe, 22-Porous distribution plate, 23-Raw material storage bin, 24-First shearer, 25-Ejector, 26-Sheared material return pipe, 27-Second shearer, 28-First-stage melter, 29-Second-stage melter, 30-Material return pipe, 31-Blower, 32-Hot air pipe, 33-Rotary feeder, 34-Venturi tube, 35-Air pressure forming device, 36-Nitrogen cooler, 37-Mixer, 38-Carbon nanotube discharge pipe, 39-Carbon nanotube conveying pipe. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the embodiments. The illustrative embodiments and descriptions of this invention are only used to explain this invention and are not intended to limit this invention.

[0043] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known materials or methods have not been specifically described in order to avoid obscuring the invention.

[0044] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described herein, as well as the features of those different embodiments or examples.

[0045] In this application, unless otherwise stated, the terms "upper," "lower," "left," "right," "front," "rear," "top," "bottom," "middle," "vertical," "horizontal," "lateral," and "longitudinal," etc., generally refer to the directions shown in the drawings or describe the relative positional relationships of the components in a vertical, perpendicular, or gravitational direction. They are used only to describe the relative positional relationships between the components or constituent parts and do not specifically limit the specific installation orientation of each component or constituent part. "Inner" and "outer" generally refer to the interior or exterior of the cavity relative to the chamber or the radial interior or exterior relative to the center of a circle. The above directional terms are defined for ease of understanding of the present invention and therefore do not constitute a limitation on the scope of protection of the present invention.

[0046] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0047] Furthermore, the terms "installation," "setup," "equipped with," "connection," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0048] Furthermore, the structures, proportions, sizes, etc., drawn in the accompanying drawings of this application are only used to complement the content disclosed in the specification for those skilled in the art to understand and read, and are not intended to limit the conditions under which this application can be implemented. Therefore, they have no substantial technical significance. Any modification to the structure, change in the proportional relationship, or adjustment of the size, without affecting the effects and purposes that this application can produce, should still fall within the scope of the technical content disclosed in this application.

[0049] Example

[0050] like Figure 1As shown, this embodiment provides a continuous production system for carbon nanotube-reinforced resin-based composite materials, including a first fluidized bed reactor 03 and a second fluidized bed reactor 17 connected in series via gas paths. The bottom of the second fluidized bed reactor 17 is connected to a carbon nanotube conveying pipe 39 that communicates with the first fluidized bed reactor 03. The bottom of the first fluidized bed reactor 03 is connected to a carbon nanotube discharge pipe 38, which is connected to a mixer 37. The mixer 37 has multiple feed pipes connected to it, and a porous distribution plate 22 is connected inside the mixer 37. A rotary feeder 33 is connected to the discharge port at the bottom of the mixer 37. The rotary feeder 33 is connected to a venturi tube 34, which is connected to a shearing structure. The shearing structure is connected to a melting structure, which is connected to a pressure forming device 35. The rear end of the pressure forming device 35 is connected to a nitrogen cooler 36.

[0051] Specifically, the shearing structure includes a first shear 24, which is connected to an ejector 25. The ejector 25 is connected to a second shear 27, which is connected to the melting structure. The second shear 27 is a rotary shear, and a shearing material return pipe 26 connects the second shear 27 and the ejector 25. The ejector 25 is a high-speed ejector.

[0052] Specifically, the melting structure includes a primary melter 28 and a secondary melter 29 connected in series. Both the primary melter 28 and the secondary melter 29 are connected to a heat source supplementation structure. A material transfer pipe connecting the shear structure and the melting structure is connected to a heating structure for the material to be melted. The heating structure for the material to be melted is a molten salt heating system. The heat source supplementation structure includes a hot air duct 32 connected to the primary melter 28 and the secondary melter 29. The hot air duct 32 is connected to a fan 31, and an air heating structure is connected to the hot air duct 32. This air heating structure is also a molten salt heating system. The temperature of the primary melter 28 and the secondary melter 29 can be controlled by adjusting the speed of the fan 31 to regulate the hot air flow. When the temperature of the melting zone deviates from the set value, the speed of the fan 31 can be adjusted. If there is incompletely melted material, it can be passed back to the primary melter 28 and the secondary melter 29 through the material return pipe 30 for remelting.

[0053] The molten structure consists of two series-connected melters. The carbonaceous product undergoes basic melting and homogenization in the first melter 28, followed by fine conditioning and spinning in the second melter 29. Both melters are equipped with spinnerets, enabling continuous and stable formation of carbon nanofibers and yielding carbon nanofiber products with ideal morphology and consistency. Through the synergistic effect of hot air, the molten structure achieves precise control over the microstructure of the carbon nanofiber product, improving the quality of the prepared carbon nanofiber product.

[0054] Specifically, both the first fluidized bed reactor 03 and the second fluidized bed reactor 17 are connected to the top of a first cyclone separator 07; the outlet pipe of the first cyclone separator 07 is connected to the catalyst inlet of the second fluidized bed reactor 17, and a first injector 18 is connected to the outlet pipe; the first injector 18 is connected to a power pipe 20, and a power pump 19 is connected to the power pipe 20, which is connected to the carbon source inlet pipe 21 of the first fluidized bed reactor 03; a hydrogen inlet pipe 01 is connected to the bottom of the first fluidized bed reactor 03. A heating structure 02 is connected to the hydrogen inlet pipe 01, and a heating structure is also connected to the carbon source inlet pipe 21. All heating structures in this system are resistance / electromagnetic heating systems.

[0055] Specifically, both the first fluidized bed reactor 03 and the second fluidized bed reactor 17 are equipped with fixed reactors 05. Each fixed reactor 05 contains a porous gas distribution plate 04, and a flow guide baffle 06 is connected to its top. The porous gas distribution plate 04 ensures uniform distribution of the reactant gas within the bed. Simultaneously, the staggered flow guide plates inside the reactor effectively extend the gas-solid phase contact time, improving raw material conversion efficiency. Meanwhile, the flow guide baffle 06 enhances airflow turbulence, allowing reactants to rapidly diffuse to the catalyst active sites. This highly turbulent environment ensures high mass transfer efficiency, enabling rapid cracking and deposition of the carbon source gas, thereby achieving high-speed growth of carbon nanotubes. Furthermore, the surface of the flow guide baffle 06 forms a synergistic interaction surface with the reactor inner wall, increasing the reaction interface area, enhancing the mass and heat transfer efficiency within the system, and significantly improving energy utilization efficiency.

[0056] Specifically, the outlet end of the first cyclone separator 07 on the second fluidized bed reactor 17 is connected to an exhaust pipe, which is connected to a catalyst recovery device and a hydrogen recovery device.

[0057] The catalyst recovery device includes a second cyclone separator 10. The top outlet of the second cyclone separator 10 is connected to a hydrogen recovery device, and the bottom is connected to a catalyst reuse pipe 09. The catalyst reuse pipe 09 is connected to two catalyst reuse branch pipes that are respectively connected to the first fluidized bed reactor 03 and the second fluidized bed reactor 17 via a tee connector.

[0058] The hydrogen recovery device includes a second injector 16, which is connected to a membrane separation unit. The membrane separation unit is connected to a pressure swing adsorption (PSA) system 12. The top of the PSA system 12 is connected to a first hydrogen recycling pipe 08, which is connected to the hydrogen inlet pipe 01 of the first fluidized bed reactor 03. The bottom of the PSA system 12 and the membrane separation unit is connected to a second hydrogen recycling pipe 15, which is connected to the hydrogen inlet pipe 01 of the second fluidized bed reactor 17.

[0059] The membrane separation unit consists of a primary membrane separation unit 14 and a secondary membrane separation unit 13, forming a two-stage membrane separation structure. It can recover and purify more than 95% of the hydrogen in the reaction tail gas and return it to the reaction system for recycling.

[0060] By connecting a hydrogen recovery unit, unreacted gases can be separated by membrane separation and pressure swing adsorption and then returned to the fluidized bed reactor for reuse, improving the utilization rate of raw materials. Through the synergistic effect of dual reactors in series and raw material recycling, product quality and production efficiency are significantly improved. It has the advantages of high conversion rate and good product consistency. Compared with traditional single reactors, the process investment cost of this reactor is reduced by more than 40% and energy consumption is reduced by more than 35%, providing a reliable technical approach for the high-value utilization of mixed carbon sources.

[0061] The ejector is the core power structure. It uses a high-pressure power gas source to generate a vacuum effect, providing stable gas flow power for the entire reaction system. The ejector ensures that the reactants form a stable sulfidation state in the fluidized bed reactor by precisely controlling the gas flow rate and pressure parameters, while realizing the efficient recycling of unreacted gases.

[0062] Specifically, a hydrogen supply pipe 11 is connected to the top of the pressure swing adsorption system 12. The purpose of connecting the hydrogen supply pipe to the top of the pressure swing adsorption system 12 is that when the hydrogen in the pressure swing adsorption system 12 cannot meet the hydrogen requirements of the second fluidized bed reactor 17, hydrogen can be added from the outside to the pressure swing adsorption system 12 to meet the reaction requirements of the second fluidized bed reactor 17.

[0063] Specifically, both the first fluidized bed reactor 03 and the second fluidized bed reactor 17 are connected to a heating structure. This heating structure is a molten salt heating system, which controls the reaction temperature in the first fluidized bed reactor and the second fluidized bed reactor 17, so that carbon nanotubes are prepared within a suitable temperature range, thereby improving product quality.

[0064] Working principle: When using this system for continuous production of carbon nanotube-reinforced resin-based composite materials, carbon nanotubes prepared through the first fluidized bed reactor 03 and the second fluidized bed reactor 17 enter the mixer 37 from the carbon nanotube discharge pipe 38. Simultaneously, other raw materials are added to the mixer 37 through other feed pipes. The porous distribution plate 22 connected to the mixer 37 disperses and mixes the raw materials evenly. After mixing, the raw materials are fed into the Venturi tube 34 through the rotary feeder 33. The Venturi effect generated by the Venturi tube 34 enables precise delivery and proportioning control of various functional materials. The raw materials are then fed into the raw material storage bin 23, and the mixture in the raw material storage bin 23 is then uniformly and slowly conveyed to the first shear. The material undergoes primary dispersion in device 24, then enters high-speed jet injector 25. After further dispersion in high-speed jet injector 25, the material enters second shearer 27 (rotary shearer) for deep processing. Some material returns to high-speed jet injector 25 via shear material return pipe 26 for further processing. The homogenized material then enters first-stage melter 28 and second-stage melter 29 sequentially. Basic plasticization of the material is completed in first-stage melter 28, and then it enters second-stage melter 29. With the assistance of hot air, the material undergoes deep melting. After melting, the material is formed by air pressure forming device 35 and then cooled and shaped in nitrogen cooler 36, thus obtaining carbon nanotube reinforced resin matrix composite material.

[0065] When preparing carbon nanotubes using the unit of the present invention, a mixed carbon source is introduced into the first fluidized bed reactor 03 through a carbon source inlet pipe 21 connected to the first fluidized bed reactor 03, and hydrogen is introduced into the first fluidized bed reactor 03 through a hydrogen inlet pipe 01 connected to the first fluidized bed reactor 03. Simultaneously, a catalyst is introduced into the first fluidized bed reactor 03 through the catalyst inlet. Both the mixed carbon source and hydrogen entering the first fluidized bed reactor 03 are first heated by a resistance / electromagnetic heating system connected to the carbon source inlet pipe 21 and the hydrogen inlet pipe 01 before entering the mixed carbon source and hydrogen inlet pipe 03. Carbon source and hydrogen are first evenly distributed through porous gas distribution plate 04 to form a stable fluidized state. Simultaneously, a resistance / electromagnetic heating system connected to fixed reactor 05 provides heating and temperature control. After the raw gas fully reacts in fixed reactor 05, carbon nanotubes and some intermediate products are generated. After separation by a cyclone separator connected to the top of the first fluidized bed reactor 03, the carbon nanotubes fall downwards through the channel formed between the guide baffle 06 and the wall of the first fluidized bed reactor 03, and are then discharged from the outlet at the bottom of the first fluidized bed reactor 03. The resulting intermediate products or remaining gas enter the second fluidized bed reactor 17 through the inlet pipe. Before entering the second fluidized bed reactor 17, the gas enters the first ejector 18. The first ejector 18 utilizes a high-pressure power gas source to generate a vacuum effect, providing stable gas flow power for the entire reaction system. Simultaneously, through precise control of gas flow rate and pressure parameters, it ensures that the reactants form a stable sulfidation state within the fluidized bed reactor. The intermediate products or residual gas generated in the first fluidized bed reactor 03 are introduced into the second fluidized bed reactor 17 through the first injector 18 for further catalytic reaction. At the same time, a mixed carbon source is introduced into the second fluidized bed reactor 17 through the carbon source inlet pipe 21. The hydrogen required in the second fluidized bed reactor 17 comes from the hydrogen recovery system. After the raw gas reacts fully in the second fluidized bed reactor 17, carbon nanotubes are formed, and some intermediate products or residual hydrogen may also be formed. The generated carbon nanotubes can be discharged directly from the discharge port at the bottom of the second fluidized bed reactor 17, or a feed pipe can be connected to the discharge port of the second fluidized bed reactor 17 to introduce the carbon nanotubes generated in the second fluidized bed reactor 17 into the first fluidized bed reactor 03, and then discharged together from the discharge port at the bottom of the first fluidized bed reactor 03.In addition, the residual gas after reaction in the second fluidized bed reactor 17 is separated by a cyclone separator and enters the second cyclone separator 10. The second cyclone separator 10 separates the hydrogen and catalyst. The separated hydrogen is then fed into a hydrogen recovery device. The hydrogen first enters the second injector 16, and then enters the primary membrane separation unit 14 and the secondary membrane separation unit 13 for separation and purification, achieving efficient hydrogen recovery. The hydrogen after being processed by the membrane separation unit enters the pressure swing adsorption system 12. When hydrogen needs to be introduced into the second fluidized bed reactor 17, the hydrogen separated in the pressure swing adsorption system 12 can be used, achieving efficient resource utilization. The separated catalyst is then reintroduced into the first fluidized bed reactor 03 and the second fluidized bed reactor 17 for use.

[0066] The continuous production system for carbon nanotube-reinforced resin-based composite materials of this invention utilizes the porous distribution plate 22 in the mixer 37 to achieve static mixing. Combined with the Venturi tube 34, this solves the pollution and energy consumption problems associated with traditional mechanical stirring. Simultaneously, the connected shear structure, melting structure, and pressure forming device 35 enable simultaneous optimization of the material's microstructure control and surface functional layer construction, achieving uniform dispersion of the functional phase in the matrix and a significant improvement in interfacial bonding strength. Furthermore, the sophisticated pipeline network enables fully enclosed material transport and precise control of process parameters, effectively improving the consistency and stability of product performance. In addition, by connecting the Venturi tube 34, the Venturi effect generated by the tube replaces the traditional mechanical transport method. This not only achieves precise transport and proportioning control of various functional materials but also ensures the performance stability of functional materials during transport through a unique sealed transport mechanism, particularly preventing performance degradation of easily oxidized materials such as boron carbide during transport. Simultaneously, by connecting the air pressure forming unit 35, a dense oxide alloy protective layer can be controllably generated on the material surface during the air pressure setting stage by introducing a specific composition of hot air into the atmosphere pressure furnace. This design, through precise control of hot air temperature, flow rate, and oxygen partial pressure, replaces the traditional surface treatment process, achieving not only simultaneous material densification and surface modification, but also significantly improving the surface hardness and oxidation resistance of the composite material through the metallurgical bonding between the oxide layer and the matrix. Furthermore, the melting structure consists of two-stage melters connected in series, allowing the carbonaceous product to undergo basic melting and homogenization in the first-stage melter 28, followed by fine tempering in the second-stage melter 29. This enables continuous and stable molding of carbon nanotube-reinforced resin matrix composites, while simultaneously obtaining carbon nanotube-reinforced resin matrix composite products with ideal morphology and consistency.

[0067] Furthermore, the continuous production system for carbon nanotube-reinforced resin-based composite materials of this invention is integrated with the carbon nanotube preparation unit, allowing the prepared carbon nanotubes to be directly mixed with other raw materials, reducing intermediate processes and improving production efficiency. Moreover, the carbon nanotube preparation unit of this invention achieves the stepwise catalytic conversion of mixed carbon sources through a two-stage fluidized bed reactor, utilizing interstage separation and recycling units to achieve efficient utilization of raw materials, realizing the direct conversion of mixed carbon sources to carbon nanotubes, improving the conversion rate of mixed carbon sources, and also improving product quality. The process is simple, energy consumption is significantly reduced, and product performance is stable. This carbon nanotube preparation unit is suitable for various operating conditions from negative pressure to medium pressure, providing a new technical path for the resource utilization of mixed carbon sources. In addition, the first fluidized bed reactor 03 and the second fluidized bed reactor 17, connected in series, can achieve continuous feeding. The first fluidized bed reactor 03 achieves catalytic activation of the mixed carbon source to obtain carbon nanotubes and some intermediate products. The formed intermediate products enter the second fluidized bed reactor 17 to continue reacting and generating carbon nanotubes. The reaction is complete through continuous feeding and discharging. This system achieves efficient gas-solid separation through an interstage separation structure, with the separated catalyst returned to the reaction system for reuse. Furthermore, the system is stable, energy-efficient, and reliable, capable of handling mixed carbon source feedstocks of varying concentrations. It boasts broad feedstock adaptability, high operational flexibility, and applicability to various industrial conditions. Compared to traditional single-reactor carbon source conversion processes, this reaction system achieves directional pyrolysis and efficient conversion of different carbon source feedstocks, improving the yield of carbon nanotubes. The carbon nanotube preparation unit exhibits strong feedstock adaptability and a short process flow, reducing energy consumption by 25-35% compared to traditional reaction beds. The product exhibits uniform structure and stable quality, making it suitable for large-scale conversion of various mixed carbon source feedstocks. The carbon nanotube preparation unit utilizes a sophisticated pipeline network to achieve fully enclosed material transport, effectively preventing contamination and improving product purity.

[0068] Experimental Example 1

[0069] The system of this invention is used for the continuous production of carbon nanotube-reinforced resin-based composite materials. The fluidized bed synthesis unit has a diameter of 200 mm, and the composite unit has a height of 650 mm. During resin-based composite production, the matrix resin is 66% polyamide, and the carbon nanotube addition is 3 wt%. The melt blending unit has a heat load of 45 kW, and the gas-assisted hot pressing unit has a pressure of 8 MPa and a temperature of 600 °C. The resulting composite material has a volume resistivity of 10⁻⁶. -3 Ω·cm, thermal conductivity is 58 W / (m·K).

[0070] Experiment Example 2

[0071] The system of this invention is used for the continuous production of carbon nanotube-reinforced resin-based composite materials. During resin-based compounding, the matrix resin is polycarbonate, and the carbon nanotube addition is 5 wt%. The heat load of the melt blending unit is 55 kW, and the pressure of the gas-assisted hot pressing unit is 10 MPa, and the temperature is 520 °C. The resulting composite material has a volume resistivity of 10 Ω·cm. -4 Ω·cm, thermal conductivity is 65 W / (m·K).

[0072] Experimental Example 3

[0073] The present invention provides a continuous system for the production of carbon nanotube-reinforced resin-based composite materials. During resin-based compounding, the matrix resin is polyphenylene sulfide, the carbon nanotube content is 8 wt%, and the boron nitride content is 15 wt%. The melt blending unit has a heat load of 65 kW, and the gas-assisted hot pressing unit has a pressure of 12 MPa and a temperature of 550 °C. The resulting composite material has a volume resistivity of 10⁻⁶. -5 Ω·cm, thermal conductivity is 48 W / (m·K).

[0074] Finally, it should be noted that the specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention. For those skilled in the art, it is obvious that this application is not limited to the details of the above exemplary embodiments, and that the present application can be implemented in other specific forms without departing from the spirit or basic characteristics of the present application. Furthermore, it should be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, the present invention will not describe various possible combinations separately. Therefore, the embodiments should be considered exemplary and non-limiting in all respects. The scope of this application is defined by the appended claims rather than the foregoing description, and therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included within this application.

Claims

1. A continuous production system for carbon nanotube-reinforced resin-based composite materials, characterized in that, The system includes a first fluidized bed reactor (03) and a second fluidized bed reactor (17) connected in series via gas paths. The bottom of the second fluidized bed reactor (17) is connected to a carbon nanotube delivery pipe (39) that communicates with the first fluidized bed reactor (03). The bottom of the first fluidized bed reactor (03) is connected to a carbon nanotube discharge pipe (38). The carbon nanotube discharge pipe (38) is connected to a mixer (37). The mixer (37) is connected to multiple feed pipes. The mixer (37) has a porous distribution plate (22) inside. A rotary feeder (33) is connected to the discharge port at the bottom of the mixer (37). The rotary feeder (33) is connected to a venturi tube (34). The venturi tube (34) is connected to a shearing structure. The shearing structure is connected to a melting structure. The melting structure is connected to a gas pressure forming device (35). The rear end of the gas pressure forming device (35) is connected to a nitrogen cooler (36).

2. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 1, characterized in that, The shearing structure includes a first shear (24), which is connected to an ejector (25), and the ejector (25) is connected to a second shear (27), which is connected to the melting structure.

3. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 1, characterized in that, The melting structure includes a primary melter (28) and a secondary melter (29) connected in series. Both the primary melter (28) and the secondary melter (29) are connected to a heat source supplementation structure. The material transfer pipeline connected to the shearing structure and the melting structure is connected to a heating structure (02) for the material to be melted.

4. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 3, characterized in that, The heat source supplementation structure includes a hot air pipe (32) connected to the primary melter (28) and the secondary melter (29), the hot air pipe (32) is connected to a fan (31), and an air heating structure (02) is connected to the hot air pipe (32).

5. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 1, characterized in that, The top of the first fluidized bed reactor (03) and the second fluidized bed reactor (17) are both connected to a product separation structure; the gas outlet of the product separation structure is connected to the catalyst inlet of the second fluidized bed reactor (17), and a first injector (18) is connected to the gas outlet; the first injector (18) is connected to a power pipe (20), and a power pump (19) is connected to the power pipe (20); the power pipe (20) is connected to the carbon source inlet pipe (21) of the first fluidized bed reactor (03); a hydrogen inlet pipe (01) is connected to the bottom of the first fluidized bed reactor (03).

6. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 1, characterized in that, Both the first fluidized bed reactor (03) and the second fluidized bed reactor (17) are equipped with a fixed reactor (05). The fixed reactor (05) is equipped with a porous gas distribution plate (04), and the top of the fixed reactor (05) is connected to a flow guide baffle (06).

7. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 5, characterized in that, The product separation structure on the second fluidized bed reactor (17) is connected to an exhaust pipe at its outlet, and the exhaust pipe is connected to a catalyst recovery device and a hydrogen recovery device.

8. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 7, characterized in that, The catalyst recovery device includes a second cyclone separator (10), the top outlet of the second cyclone separator (10) is connected to a hydrogen recovery device, and the bottom is connected to a catalyst reuse pipe (09). The catalyst reuse pipe (09) is connected to two catalyst reuse branch pipes that are respectively connected to the first fluidized bed reactor (03) and the second fluidized bed reactor (17) through a three-way connector.

9. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 7, characterized in that, The hydrogen recovery device includes a second injector (16), which is connected to a membrane separation unit, and the membrane separation unit is connected to a pressure swing adsorption system (12).

10. The preparation system for continuous production of carbon nanotube-reinforced resin-based composite materials according to claim 9, characterized in that, The top of the pressure swing adsorption system (12) is connected to a first hydrogen recycling pipe (08) that is connected to the hydrogen inlet pipe (01) of the first fluidized bed reactor (03); the bottom of the pressure swing adsorption system (12) and the membrane separation unit is connected to a second hydrogen recycling pipe (15) that is connected to the hydrogen inlet pipe (01) of the second fluidized bed reactor (17).

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