Method for scaling, regulating and controlling fluidized bed for producing carbon material

Abstract

A carbon material is a widely popular novel material and has huge market demand, in order to meet the demand of large-scale production, the invention provides a fluidized bed scaling and regulating method for carbon material production, and the method aims to improve the production efficiency and reduce the production cost. The method comprises the following specific steps: (1) measuring and calculating geometrical parameters and operation conditions of an original fluidized bed; (2) calculating geometric parameters and operation conditions of the fluidized bed after scaling according to a similarity rule of the fluidized bed for producing the carbon material; step (3), realizing scaling of the fluidized bed and / or fluidization performance regulation and control in the fluidized bed through geometric parameters and operation conditions calculated by the fluidized bed scaling method; through the innovative method, accurate parameters required by different scales of carbon material production fluidized beds can be quickly determined, so that the amplification process of the industrial fluidized bed is accelerated, the raw material loss is reduced, the product yield and quality are remarkably improved, and the conversion from laboratory achievements to actual production is accelerated.

Description

Technical Field

[0001] The present invention relates to the field of fluidized bed for producing carbon materials, and in particular to a method for scaling and regulating a fluidized bed for producing carbon materials. Background Art

[0002] Carbon is one of the most closely related and vital elements in nature. The carbon materials it forms have excellent electrical, thermal and mechanical properties, and they have an irreplaceable position in many high-tech fields such as energy, electronics, aerospace, and biomedicine. At present, the main production method of large quantities of carbon materials relies on chemical vapor deposition to achieve efficient production in fluidized bed reactors. However, with the growing market demand for carbon materials, the problem of scaling up fluidized bed reactors has become increasingly prominent, becoming a key bottleneck restricting the widespread application of carbon materials. Traditionally, the scale-up process of carbon material fluidized beds often relies on the technical staff's experience accumulation and trial and error, lacking systematic theoretical guidance and accurate scaling calculation models. This experience-based method is not only inefficient, but also difficult to ensure the stable operation of the fluidized bed after scale-up and the consistency of product quality. Especially when transitioning from experimental scale (fluidized bed with cylindrical section diameter less than 0.14 meters) to industrial scale (fluidized bed with cylindrical section diameter greater than or equal to 0.14 meters), the significant changes in fluidization characteristics make it difficult to directly apply the operating parameters and performance indicators obtained in the experiment to industrial production, resulting in low production efficiency and large fluctuations in product quality. Therefore, it is particularly necessary and urgent to develop a calculation formula for the expansion and contraction of fluidized beds and a flow field control method for the production of carbon materials based on scientific theory. This method needs to comprehensively consider multiple factors such as the geometric structure of the fluidized bed, fluid dynamics, the interaction between reactants and products, and the heat and mass transfer process. Through mathematical modeling and numerical simulation, it reveals the inherent laws in the expansion and contraction process of the fluidized bed, and provides precise guidance for the optimal design and operation of the fluidized bed. In summary, the development of a calculation formula for the expansion and contraction of fluidized beds and a flow field control method for the production of carbon materials based on theoretical science is of great significance for promoting the rapid development of the carbon materials industry and improving product quality and production efficiency. Summary of the invention

[0003] In view of the above analysis, the present invention provides a method for scaling and controlling a fluidized bed for producing carbon materials, so as to solve the problem that there is a large error between the fluidization characteristics of a fluidized bed for producing carbon materials on an industrial scale obtained by empirical estimation and the fluidization characteristics of a fluidized bed for producing carbon materials on an experimental scale.

[0004] The present invention proposes a specific scaling and control method for a fluidized bed for producing carbon materials, which aims to solve the problem of fluidization performance change that may be encountered during the scaling process of the fluidized bed, and includes the following steps: Step (1): measuring and calculating the geometric parameters and operating conditions of the original fluidized bed; the geometric parameters at least include the cone angle of the cone section, the air inlet method, the air inlet position of the original fluidized bed, the diameter and height of the cone section, the cylindrical section and the expansion section of the original fluidized bed; the operating conditions at least include the bed pressure drop, gas velocity, inlet pressure, static bed volume inside the reactor during the fluidization process of the original fluidized bed, the particle sphericity, particle density, particle microscopic three-dimensional structure, and van der Waals force between particles of the carbon material particles; Step (2): using the geometric similarity criterion, gravity similarity criterion, drag similarity criterion, particle density and fluid density similarity criterion, pressure similarity criterion, and particle bed volume similarity criterion to jointly calculate the geometric parameters and operating conditions of the scaled fluidized bed; Step (3): Designing a scale-up or scale-down experiment; designing a scale-up or scale-down experiment through these parameter conditions, verifying the geometric parameters and operating conditions calculated by the fluidized bed scaling method, and further regulating and optimizing according to the experimental results to ensure that the fluidized bed can still maintain stable fluidization performance after being scaled up or down.

[0005] The above-mentioned method for scaling and controlling a fluidized bed for producing carbon materials, wherein the fluidized bed is divided into a conical section, a cylindrical section and an expansion section from top to bottom, wherein the design of the conical section has an important influence on the initial distribution of the gas and the formation of the flow field, such as Figure 2 shown.

[0006] In the above-mentioned method for scaling and controlling a fluidized bed for producing carbon materials, the cone angle of the cone section in step (1) refers to the angle of the cone portion of the cone section. The cone angle of the cone section is one of the key parameters, and its size directly affects the flow pattern and velocity distribution of the gas after entering the fluidized bed. Figure 2 shown.

[0007] In the above-mentioned method for scaling and regulating a fluidized bed for producing carbon materials, the air intake method in step (1) is divided into two types: direct air intake and refraction air intake. The direct air intake method is simple and direct, but may lead to uneven gas distribution; the refraction air intake makes the gas more evenly distributed in the entire bed through the guiding effect of the cone segment. During the scaling process, the air intake method is flexibly selected or adjusted according to the changes in the size of the fluidized bed and production needs to optimize the flow field characteristics.

[0008] The method for scaling and regulating a fluidized bed for producing carbon materials according to claim 1 is characterized in that the carbon material particles described in step (1) specifically include a variety of nanoscale carbon material particles produced by a fluidized bed process, and these particles include but are not limited to carbon nanotubes, graphene, fullerenes, carbon spheres, and particles composed of doped forms of these nano-carbon materials; this feature clarifies the scope of carbon materials to which the method is applicable, emphasizes its application value in the field of production of nano-carbon materials and modified materials thereof, and provides an important basis for the precise control and optimization of the carbon material production process.

[0009] The method for scaling and regulating a fluidized bed for producing carbon materials according to claim 1 is characterized in that the geometric similarity in step (2) requires not only that the cone angles of the cone sections corresponding to the two fluidized beds are equal, but also that the shapes of the gas distributor and the internal components are similar to ensure the uniformity of the gas flow distribution. At the same time, the equality of the cone section height and the aspect ratio of the cylindrical section, as well as the similarity of the volume of the particle bed in the fluidized bed, are key elements for maintaining the consistency of the geometric structure of the fluidized bed; in terms of dynamic similarity, the method requires that all corresponding forces remain consistent in direction and change in the same proportion in size; this includes at least viscosity, drag, gravity, pressure, all of which are forces related to fluid dynamics, and the similarity of particle density and fluid density.

[0010] According to the scaling and control method for a fluidized bed for producing carbon materials as described in claim 3, its characteristics further specify the definition of similar volume of the fluidized bed particle bed layer; here, the similar volume of the fluidized bed particle bed layer refers to the proportional relationship between the total volume of the particles and the bed volume they occupy in a non-fluidized state, that is, when the particles are in a static stacking state; this proportional relationship should remain similar in the fluidized bed before and after scaling to ensure the consistency of the distribution and stacking state of the particles in the bed layer, thereby maintaining the stability of the fluidization performance; by strictly controlling this ratio, the present method can more accurately predict and control the behavior of particles in the fluidized bed after scaling, thereby improving the efficiency of carbon material production and product quality.

[0011] The method for scaling and regulating a fluidized bed for producing carbon materials according to claim 1 is characterized by a specific implementation method of the drag similarity in step (2); here, drag similarity is defined as the ratio between the drag force exerted on the carbon material particles in the fluidized bed and their inertial force remaining consistent in the fluidized bed before and after scaling; drag is the resistance exerted by the fluid on the movement of particles, while inertial force is the force exerted by the particles in motion due to their own mass; by ensuring that the ratio of drag force to inertial force is similar, the method can effectively simulate and predict the movement state and trajectory of the particles in the fluidized bed after scaling, thereby achieving precise regulation of the fluidization performance.

[0012] According to the method for scaling and regulating a fluidized bed for producing carbon materials as described in claim 1, it is characterized in that the specific description of gravity similarity in step (2) is further refined; here, gravity similarity is defined as the ratio between the gravity and the inertia force exerted on the carbon material particles in the fluidized bed remains consistent in the fluidized bed before and after scaling; gravity is the earth's attraction to the particles, and the inertia force is the force generated by the particles to maintain their original state of motion; in the fluidized bed, gravity and inertia act together on the particles, affecting their motion trajectory and distribution state; by ensuring that the ratio of gravity to inertia is similar, this method can more accurately simulate the movement behavior of the particles in the fluidized bed after scaling, thereby achieving precise regulation of the fluidization performance.

[0013] The method for scaling and regulating a fluidized bed for producing carbon materials according to claim 1 is characterized in that the details of gravity similarity in step (2) are further deepened; here, gravity similarity is precisely defined as the ratio between the gravity borne by the carbon material particles in the fluidized bed environment and the inertial force generated by maintaining their own motion inertia, which needs to be maintained constant before and after the fluidized bed is scaled; gravity, as the natural gravitational force given by the earth to the particles, interacts with the inertial force of the particles trying to maintain their existing motion state, and together shapes the motion trajectory and spatial distribution of the particles in the fluidized bed; by strictly ensuring the similarity of this ratio, this method can achieve accurate simulation of the particle motion pattern in the scaled fluidized bed, thereby achieving detailed regulation of the fluidization performance.

[0014] The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1 is characterized in that the similarity between the particle density and the fluid density mentioned in step (2) is determined by calculating the dimensionless ratio of the fluid density to the particle density in the fluidized bed; this ratio needs to remain consistent in the fluidized bed before and after scaling to ensure that the interaction forces between the fluid and the particles, such as drag and buoyancy, can be scaled proportionally to maintain the stability of the fluidization performance; this feature is crucial for accurately simulating and controlling the flow and particle behavior in the scaled fluidized bed, and helps to improve the predictability and efficiency of carbon material production.

[0015] The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1 is characterized in that the method specifically realizes the dynamic adjustment of the geometric volume of the fluidized bed in step (3), including but not limited to the scaling and reduction of the fluidized bed volume by mechanical structure or gas pressure means. This process is intended to optimize the production process of carbon materials and adapt to different production requirements or improve production efficiency by adjusting the geometric dimensions of the fluidized bed.

[0016] The method for scaling and regulating a fluidized bed for producing carbon materials according to claim 1 is characterized in that step (3) specifically involves fine regulation of the fluidization performance in the fluidized bed, and the regulation process is intended to achieve a flow field characteristic of one fluidized bed that is highly similar to the flow field characteristic of another geometrically similar fluidized bed. This regulation method adjusts fluid parameters (such as flow rate, pressure, temperature) and / or the internal structure design of the fluidized bed (such as gas distribution plates, baffles) to ensure that fluidized beds at different scales or operating conditions can maintain similar flow field states, thereby optimizing the production efficiency and quality of carbon materials.

[0017] In the above-mentioned method for scaling up and down a fluidized bed for producing carbon materials, method 1 is used to calculate the gravity similarity criterion in the fluidized bed for producing carbon materials: Method 1: Where: g is the neutral acceleration; d p is the equivalent diameter of carbon material particles; u 0 is the superficial fluid velocity.

[0018] In the above-mentioned method for scaling up and down a fluidized bed for producing carbon materials, the similarity criterion for calculating the internal drag of a fluidized bed for producing carbon materials using method 2 is as follows: Method 2: Where β is the inertia coefficient of the particle; ρ p is the density of carbon material particles.

[0019] In the above-mentioned method for scaling up a fluidized bed for producing carbon materials, method three is used to calculate the similarity criterion between the particle density and the fluid density in the fluidized bed for producing carbon materials: Method 3: Among them, ρ f is the density of the fluid; ρ p is the density of carbon material particles.

[0020] In the above-mentioned method for scaling up and down a fluidized bed for producing carbon materials, method 4 is used to calculate the similarity criterion of the pressure in the fluidized bed for producing carbon materials: Method 4: where p 0 is the fluid pressure in the fluidized bed.

[0021] In the above-mentioned method for scaling up a fluidized bed for producing carbon materials, method 5 is used to calculate the similarity criterion for the volume of the fluidized bed particle layer: Method 5: Where D is the diameter of the fluidized bed, V p is the bed volume occupied by particles.

[0022] In the above-mentioned method for scaling up and down a fluidized bed for producing carbon materials, in the above-mentioned method 2, the inertia coefficient β of the particles is calculated using the following formula: When the bed porosity ε is less than 0.8 during complete fluidization, the particle inertia coefficient β is calculated by the following formula: The inertia coefficient of the particle Where: μ f is the fluid viscosity; ρ f is the density of the fluid; ε is the porosity of the bed; is the fluid velocity with direction; is the particle velocity with direction. When the bed porosity ε is greater than or equal to 0.8 during complete fluidization, the particle inertia coefficient β is calculated by the following formula: The inertia coefficient of the particle Among them, C D is the apparent drag coefficient of the particle: When turbulent flow occurs in the fluidized bed, the Reynolds number Re>1000. At this time, according to the Newton formula, the apparent drag coefficient of the particle is set to C D = 0.44. When the Reynolds number of the relative motion between the particle and the fluid is small enough, the inertial force is much smaller than the viscous force, and the drag coefficient is

[0023] The above method significantly narrows the gap in flow characteristics between experimental-scale fluidized beds and industrial-scale fluidized beds through refined fluidized bed structure design and optimized air intake strategies. This breakthrough not only improves the accuracy of scaling, but also ensures the effective application of experimental data in larger-scale production.

[0024] Compared with the existing technology, the core advantage of the present invention is that it can almost perfectly reproduce the flow characteristics of the experimental scale fluidized bed on an industrial scale. This feature greatly simplifies the conversion process from laboratory to production line, effectively reduces unnecessary loss of raw materials, and significantly improves the yield and quality of products. In addition, it also accelerates the transformation process of experimental research results into practical production applications, injecting new vitality and impetus into the rapid development of the carbon material industry. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1is a flow chart of the amplification method of the present invention; Figure 2 It is a schematic diagram of the geometric shape of the enlarged fluidized bed of the present invention; Reference numerals 1-conical section; 2-cylindrical section; 3-expansion section; 4-carbon material particles; 5-fluid inlet; 6-dust baffle; 7-gas outlet; 8 - Experimental scale fluidized bed; 9 - Industrial scale fluidized bed.

[0023] The drawings are only for the purpose of illustrating particular embodiments and are not to be considered limiting of the present invention. Like reference symbols denote like components throughout the drawings. DETAILED DESCRIPTION

[0024] In view of the wide application of carbon materials in high-end fields such as aerospace, energy storage, biosensors and vacuum electronic devices, and their excellent mechanical, thermal and electrical properties, the market demand for carbon materials continues to grow, showing great development potential. In order to meet this huge market demand, it is urgent to efficiently scale up the existing carbon material preparation technology from laboratory scale to industrial-grade production. The core of the present invention is to scientifically derive the geometric configuration and optimal operating conditions suitable for industrial-scale fluidized beds by accurately analyzing the key parameters in the experimental-scale fluidized bed, so as to ensure the stability of the process and the consistency of product quality during the scale-up process.

[0025] The implementation of the present invention first relies on at least one experimental scale fluidized bed device for producing carbon materials. In this device, through small-scale trial production, the optimal catalyst types (covering iron, cobalt, nickel metal elements and their composites, such as pure metal catalysts, metal oxide catalysts, nanoclusters and single-atom catalysts), catalyst shapes (such as particle size and sphericity), gas source selection, reaction temperature, reaction time and fluidization state are systematically explored and determined. The fine control of these parameters has a decisive influence on the performance and structure of the final product, and also lays a solid foundation for subsequent industrial scale-up production.

[0026] Taking the fluidized bed for carbon nanotube production as an example, the present invention adopts chemical vapor deposition (CVD) to efficiently prepare carbon nanotubes under low temperature and low pressure conditions. In this method, transition metal iron, cobalt, and nickel are selected as catalysts, and carbon-containing gases such as methane or propane are used as carbon sources. The catalyst is pre-prepared into nano-scale particles and placed in a fluidized bed. According to the "gas-liquid-solid" growth mechanism, the gaseous carbon source is adsorbed and cracked on the surface of the catalyst particles to form C1 and C2 small molecular carbon species, which are then dissolved and diffused into the interior of the catalyst. When the internal carbon concentration reaches saturation, carbon nanotubes are precipitated on the other side of the catalyst, and self-assembled into a graphite sheet cylindrical structure, i.e., carbon nanotubes, due to the guiding effect of the catalyst.

[0027] During the growth of carbon nanotubes, the nanoagglomeration phenomenon is particularly significant. Due to the action of van der Waals forces, carbon nanotubes tend to bend and agglomerate with each other when growing on the surface of catalyst particles, forming a complex three-dimensional network structure. The type of fluidizing gas and the fluidizing state have an important influence on the morphology, structure and quantity of the agglomerates. Under a stable fluidizing environment, primary agglomerates can be decomposed into smaller agglomerates, and then form more fragile secondary agglomerates through the re-agglomeration process. This process not only affects the structural stability of the catalyst, but also directly determines the performance and quality of the final carbon nanotube product. Therefore, by precisely controlling the fluidization conditions, the growth process of carbon nanotubes can be effectively regulated to improve product quality and yield.

[0028] The heterogeneous mixture of solids and gases in the fluidized bed has the properties of a liquid, so it is difficult to accurately describe the phenomena in the fluidized bed, especially when the solid particles have a special shape or microstructure, the degree of disorder in the bed will be further increased. Many good operating conditions and fluidization behaviors obtained at the experimental scale will change dramatically when they are scaled up to the industrial level. In serious cases, they may even cause scale-up accidents, causing harm to the safety of plant operation and economic investment. Therefore, the scale-up of the fluidized bed for the production of carbon materials needs to be very precise, and the fluidization morphology in the fluidized bed cannot be easily changed during the scale-up process.

[0029] The embodiment is to enlarge the experimental scale fluidized bed with a diameter of 100 mm to an industrial scale fluidized bed with a diameter of 300 mm. First, it is necessary to determine that the shape structure, gas distribution device structure, and reactor internal component layout of the enlarged industrial scale fluidized bed are similar to those of the experimental scale fluidized bed, and the aspect ratio of the cylindrical section and the cone angle of the conical section are equal to those of the experimental scale fluidized bed. Among them, the similarity of the shape and structure of the fluidized bed means that the core fluidized area is cylindrical, conical, or square. The similarity of the structure of the gas distribution device means using gas distribution plates of the same shape and the same opening rate, or not using gas distribution plates at all.

[0030] This example focuses on the precise scaling of the carbon nanotube production fluidized bed, selects carbon nanotube cluster particles with consistent microstructure, sphericity and van der Waals force as the fluidized medium, and only adjusts the average particle size and minimum fluidization speed to adapt to industrial scale. Through scientific planning and strict execution, the scaled fluidized bed is ensured to operate stably, and the production efficiency is optimized with the help of real-time monitoring and feedback mechanisms.

[0031] Use a ruler to accurately measure the static bed height, fluidized bed inner diameter, and cone angle.

[0032] A high-speed camera captures the changes in particle concentration in the bed during the fluidization process.

[0033] Consult the literature to obtain the air density and viscosity data under experimental conditions.

[0034] The average particle size of carbon nanotube cluster particles was determined by sieving method.

[0035] The minimum fluidization velocity of particles was measured by the bed collapse method.

[0036] The flow meter records the flow rate at the fluidized bed inlet to calculate the superficial fluidization velocity.

[0037] Mercury intrusion method is used to measure the true density of particles.

[0038] The pressure changes inside the fluidized bed are monitored in real time by the pressure detection devices built into the gas inlet and above the fluidized bed.

[0039] Through measurement, the inner diameter D = 0.1m and the static bed height H of the experimental scale fluidized bed were obtained. mf = 0.2m, cone angle θ = 11°, bed particle concentration ε during fluidization = 0.5, density of fluidizing air ρ f =0.00129 g cm -3 、Gas viscosity μ f =1.81×10 -5 kg / (m·s), average particle size of carbon nanotube cluster particles d p =350μm, minimum fluidization velocity of particles U mf =0.016m / s, superficial fluidization velocity U 0 =0.042m / s, fluidized bed internal pressure p 0 =525Pa, particle true density ρ p =1.51 g cm -3 .

[0040] By calculating the first method, we can get the dimensionless viscosity of the resistance in the fluidized bed.

[0041] By calculating the second method, we can get the dimensionless inertia of the fluid in the fluidized bed:

[0042] The dimensionless ratio of the density of the fluid and particles in the fluidized bed can be calculated by method 3:

[0043] The dimensionless ratio of the pressure and inertial force on the particles in the fluidized bed can be calculated by method 4:

[0044] By using method 5, we can calculate the ratio of the total volume of particles to the volume of the bed they occupy under non-fluidized conditions.

[0045] Through measurement, the inner diameter of the industrial-scale fluidized bed is D = 0.3m, the cone angle θ = 11°, and the density of the fluidizing air ρ f=0.00129 g cm -3 、Gas viscosity μ f =1.81×10 -5 kg / (m·s), average particle size of carbon nanotube cluster particles d p =350μm, particle true density ρ p =1.51 g cm -3 , fluidization pressure p 0 =550Pa.

[0046] By using the condition that the dimensionless data in the two fluidized beds are equal, the operating conditions of the industrial-scale fluidized bed are obtained by back-calculation: the minimum fluidization velocity of the particles U mf =0.020m / s, superficial fluidization velocity U 0 =0.028m / s, bed particle concentration during fluidization ε = 0.5, static bed height H mf =0.6m.

[0047] The operating conditions obtained through detailed calculation and experimental optimization were successfully applied to a 300 mm fluidized bed system, achieving a perfect bubbling fluidization state. This achievement not only demonstrated the effectiveness and accuracy of the proposed method, but also proved its applicability in actual production environments. The experimental results showed that the fluidization characteristics of the fluidized bed under this operating condition were highly similar to those of the experimental scale fluidized bed, and were fully able to meet the high standards of industrial production for fluidization quality, stability and efficiency.

[0048] The above is only one of the specific embodiments of the present invention, and is intended to elaborate the technical concept and practical application of the present invention in detail through examples. However, the protection scope of the present invention is not limited to the specific embodiments described above. Any technician familiar with the technical field, on the basis of understanding the basic principles and technical features of the present invention, can make various forms of changes, modifications, substitutions or combinations within the technical scope disclosed by the present invention. These changes or replacement technical solutions, as long as they comply with the essential spirit and claims of the present invention, should be deemed to fall within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the scope defined by the claims, rather than being limited to the specific content of the above text description.

Claims

1. The present invention proposes a specific method for scaling and regulating a fluidized bed for producing carbon materials, which aims to solve the problem of fluidization performance changes that may be encountered during the scaling process of the fluidized bed, and includes the following steps: Step (1): measuring and calculating the geometric parameters and operating conditions of the original fluidized bed; The geometric parameters at least include the cone angle of the cone section, the air inlet method, the air inlet position of the original fluidized bed, the diameter and height of the cone section, the cylindrical section and the expansion section of the original fluidized bed; the operating conditions at least include the bed pressure drop, gas velocity, inlet pressure, static bed volume inside the reactor during the fluidization process of the original fluidized bed, the particle sphericity, particle density, particle microscopic three-dimensional structure, and van der Waals force between particles of the carbon material particles; Step (2): using the geometric similarity criterion, gravity similarity criterion, drag similarity criterion, particle density and fluid density similarity criterion, pressure similarity criterion, and particle bed volume similarity criterion to jointly calculate the geometric parameters and operating conditions of the scaled fluidized bed; Step (3): Design a scale-up or scale-down experiment; Through these parameter conditions, scale-up or scale-down experiments are designed to verify the geometric parameters and operating conditions calculated by the fluidized bed scaling method, and further regulation and optimization are carried out according to the experimental results to ensure that the fluidized bed can still maintain stable fluidization performance after being scaled up or down.

2. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The carbon material particles described in step (1) specifically include a variety of nanoscale carbon material particles produced by a fluidized bed process, including but not limited to carbon nanotubes, graphene, fullerenes, carbon spheres, and particles composed of doped forms of these nanocarbon materials; this feature clarifies the scope of carbon materials to which the method is applicable, emphasizes its application value in the field of production of nanocarbon materials and their modified materials, and provides an important basis for the precise control and optimization of the carbon material production process.

3. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The geometric similarity criterion in step (2) requires not only that the cone angles of the cone sections corresponding to the two fluidized beds are equal, but also that the shapes of the gas distributor and the internal components are similar to ensure the uniformity of the gas flow distribution; at the same time, the equality of the cone section height and the aspect ratio of the cylindrical section, as well as the similarity of the volume of the particle bed in the fluidized bed, are key factors in maintaining the consistency of the geometric structure of the fluidized bed; in terms of dynamic similarity, this method requires that all corresponding forces remain consistent in direction and change in the same proportion in magnitude; this includes at least viscosity, drag, gravity, pressure, all of which are forces related to fluid dynamics, as well as the similarity of particle density and fluid density.

4. The scaling and control method for a fluidized bed for producing carbon materials according to claim 3 is characterized in that the definition of similar volume of the fluidized bed particles is further specified; here, the similar volume of the fluidized bed particles refers to the proportional relationship between the total volume of the particles and the volume of the bed they occupy in a non-fluidized state, that is, when the particles are in a static stacking state; this proportional relationship should remain similar in the fluidized bed before and after scaling to ensure the consistency of the distribution and stacking state of the particles in the bed, thereby maintaining the stability of the fluidization performance; by strictly controlling this ratio, the present method can more accurately predict and control the behavior of particles in the fluidized bed after scaling, thereby improving the efficiency of carbon material production and product quality.

5. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The specific implementation method of the drag similarity in step (2); here, drag similarity is defined as the ratio between the drag force on the carbon material particles in the fluidized bed and their inertial force remains consistent in the fluidized bed before and after scaling; drag is the resistance exerted by the fluid on the movement of particles, while inertial force is the force exerted by the particles in motion due to their own mass; by ensuring that the ratio of drag force to inertial force is similar, the present method can effectively simulate and predict the movement state and trajectory of particles in the fluidized bed after scaling, thereby achieving precise control of the fluidization performance.

6. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The specific description of gravity similarity in step (2) is further refined; here, gravity similarity is defined as the ratio between the gravity and the inertia force of the carbon material particles in the fluidized bed remains consistent in the fluidized bed before and after scaling; gravity is the earth's attraction to the particles, while the inertia force is the force generated by the particles to maintain their original state of motion; in the fluidized bed, gravity and inertia act together on the particles, affecting their motion trajectory and distribution state; by ensuring that the ratio of gravity to inertia is similar, the method can more accurately simulate the motion behavior of the particles in the fluidized bed after scaling, thereby achieving precise control of the fluidization performance.

7. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The details of gravity similarity in step (2) are further deepened; here, gravity similarity is precisely defined as the ratio between the gravity exerted on the carbon material particles in the fluidized bed environment and the inertial force generated by the particles due to maintaining their own inertia of motion, which needs to be kept constant before and after the fluidized bed is expanded and contracted; gravity, as the natural attraction given by the earth to the particles, interacts with the inertial force of the particles trying to maintain their existing state of motion, and together shapes the motion trajectory and spatial distribution of the particles in the fluidized bed; by strictly ensuring the similarity of this ratio, this method can achieve accurate simulation of the particle motion pattern in the fluidized bed after expansion, thereby achieving detailed control of the fluidization performance.

8. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The similarity between the particle density and the fluid density mentioned in step (2) is determined by calculating the dimensionless ratio of the fluid density to the particle density in the fluidized bed; this ratio must remain consistent in the fluidized bed before and after scaling to ensure that the interaction forces between the fluid and the particles, such as drag and buoyancy, can be scaled proportionally to maintain the stability of the fluidization performance; This feature is critical to accurately simulate and control the flow and particle behavior within a scaled fluidized bed, helping to improve the predictability and efficiency of carbon material production.

9. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: The method specifically implements the dynamic adjustment of the geometric volume of the fluidized bed in step (3), including but not limited to the enlargement and reduction of the volume of the fluidized bed by mechanical structure or gas pressure means; this process is intended to optimize the production process of carbon materials by adjusting the geometric dimensions of the fluidized bed to adapt to different production needs or improve production efficiency.

10. The method for scaling and controlling a fluidized bed for producing carbon materials according to claim 1, characterized in that: Step (3) specifically involves fine-tuning the fluidization performance in the fluidized bed, the purpose of which is to achieve a flow field characteristic of one fluidized bed that is highly similar to the flow field characteristic of another fluidized bed with similar geometry; This control method adjusts fluid parameters (such as flow rate, pressure, temperature) and / or the internal structure design of the fluidized bed (such as gas distribution plates, baffles) to ensure that the fluidized bed at different scales or operating conditions can maintain a similar flow field state, thereby optimizing the production efficiency and quality of carbon materials.

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