A preparation method and system for carbonized particles

Abstract

The present application provides a method and a system for preparing carbonized particles. A high-temperature reaction zone is arranged at a position close to the bottom of a carbonization fluidized bed, a low-temperature reaction zone is arranged at a position close to the outlet of the carbonization fluidized bed, and an overflow pipe is arranged between the two. During preparation, heat carrier particles such as magnesium oxide and polymer particles are introduced into the low-temperature reaction zone, and are in countercurrent contact with the fluidizing gas for compounding and carbonization. The substantially solidified particles move to the high-temperature reaction zone through the overflow pipe for sufficient carbonization. The advantage of this method is that the heat carrier particles effectively disperse polymer particles such as resin, avoiding softening and adhesion during high-temperature carbonization, achieving the effect of continuous operation. After the heat carrier particles are dissolved subsequently, porous carbonized particles can be formed. This method can reduce the grinding energy consumption and cost, and can also realize the control of the carbonization degree at different temperatures, saving energy and reducing material consumption during subsequent activation.

Description

Technical Field

[0001] This application relates to the technical field of electrochemical energy storage electrode materials or environmental protection materials. Specifically, it relates to a preparation method and system for carbonized particles. Background Art

[0002] Devices based on clean electrochemical energy storage mechanisms, such as various secondary batteries, supercapacitors, lithium-ion capacitors, or their hybrid devices, are important electrical energy storage systems and have witnessed significant development in recent years. The positive electrode materials of supercapacitors and lithium-ion capacitors are porous activated carbons with a large specific surface area. Secondary batteries, such as lithium-ion negative electrode materials (silicon-carbon negative electrodes), also use porous activated carbons with a large specific surface area as the fixing carriers for silicon particles, accounting for approximately 50% of the weight of the silicon-carbon negative electrode.

[0003] Porous carbon mainly consists of biomass or organic polymers as precursors, and is composed of steps of carbonization (dehydrogenation and deoxygenation or other elements at high temperatures) and activation (pore formation). Among them, in the carbonization process, some precursor particles become soft and viscous at high temperatures, forming particularly large viscous aggregates, resulting in less controllable particle size and density. At the same time, there is also the phenomenon of sticking to the wall, which is particularly difficult to operate in engineering. For the generated huge carbonized aggregates or particles, they still need to be ground into small particles before subsequent steps can be carried out. Moreover, the strength of the carbonized aggregates is particularly high, so a large amount of mechanical energy needs to be consumed, making the carbonization process cumbersome, energy-consuming, costly, and the quality of the generated products is relatively low. Summary of the Invention

[0004] To solve the above problems, this application provides a preparation method and system for carbonized particles. By using heat carrier particles, the purpose of dispersing polymer particles (i.e., organic precursor particles) is achieved at a relatively low temperature, so that the carbonized particles are not easily grown or aggregated, avoiding subsequent grinding and other steps, and effectively reducing the consumption of mechanical energy. And by setting up a carbonization fluidized bed with two-stage variable temperature, both compounding and carbonization are easily controllable in engineering, and the carbonized products are easily activated, further reducing costs.

[0005] In a first aspect, this application provides a preparation method for carbonized particles, the method comprising:

[0006] Under the action of a fluidizing gas, the polymer particles and the heat carrier particles are subjected to a first high-temperature treatment at 200 °C - 400 °C. After 0.5 h - 20 h, a composite carbonized material is obtained;

[0007] The temperature is then raised to 500 °C - 950 °C for a second high-temperature treatment. After 0.5 h - 20 h, the carbonized particles are obtained;

[0008] Among them, the polymer particles include at least one of epoxy resin, phenolic resin, urea-formaldehyde resin, unsaturated resin and polycarbonate resin; the heat carrier particles include at least one of magnesium oxide, sodium chloride, potassium chloride, calcium chloride, calcium oxide, sodium silicate, calcium carbonate, sodium carbonate and magnesium carbonate.

[0009] Furthermore, the mass ratio of the polymer particles to the heat carrier particles is 1:(1 - 3).

[0010] Furthermore, the diameter of the polymer particles is 5 μm - 50 μm;

[0011] The diameter of the heat carrier particles is 50 μm - 200 μm.

[0012] Furthermore, the temperature of the first high-temperature treatment is 270 °C - 360 °C.

[0013] Furthermore, the temperature of the second high-temperature treatment is 750 °C - 900 °C, and the time of the second high-temperature treatment is 3 h - 12 h.

[0014] Furthermore, the fluidizing gas includes at least one of N2, CO, H2, Ar, He, CO2 and CH4.

[0015] Furthermore, the process of the first high-temperature treatment includes:

[0016] The heat carrier particles are in a fluidized state under the action of the fluidizing gas, and the polymer particles are melted and softened at a temperature of 200 °C - 400 °C and bonded and cured with the fluidized heat carrier particles to obtain the composite carbonized material.

[0017] In a second aspect, the present application provides a preparation system for carbonized particles. The system is used to execute the preparation method of the carbonized particles described in the first aspect above. The system includes: a carbonization fluidized bed;

[0018] A porous distribution plate is arranged in the carbonization fluidized bed, and the porous distribution plate divides the carbonization fluidized bed into a low-temperature reaction zone and a high-temperature reaction zone;

[0019] The low-temperature reaction zone is provided with a mixed raw material inlet, and the mixed raw material inlet is used to introduce polymer particles and heat carrier particles into the low-temperature reaction zone; the low-temperature reaction zone is used to perform the first high-temperature treatment on the polymer particles and the heat carrier particles to obtain a composite carbonized material;

[0020] The high-temperature reaction zone is used for performing a second high-temperature treatment on the composite carbonized material to convert it into carbonized particles. The high-temperature reaction zone is provided with a fluidizing gas inlet, and the fluidizing gas inlet is used to introduce fluidizing gas into the carbonization fluidized bed so that the mixed raw materials and the composite carbonized material in the carbonization fluidized bed are in a fluidized state.

[0021] Furthermore, an overflow pipe is arranged outside the carbonization fluidized bed. One end of the overflow pipe is connected to the low-temperature reaction zone and the other end is connected to the high-temperature reaction zone. The composite carbonized material flows to the high-temperature reaction zone through the overflow pipe.

[0022] A tail gas outlet is provided on the carbonization fluidized bed, and the fluidizing gas is discharged from the carbonization fluidized bed through the tail gas outlet.

[0023] A carbonized material outlet is provided on the carbonization fluidized bed, and the carbonized particles are discharged from the high-temperature reaction zone along the carbonized material outlet.

[0024] In a third aspect, the present application provides carbonized particles obtained by the preparation method of the carbonized particles described in the first aspect above. The particle size of the carbonized particles is 5 μm - 80 μm.

[0025] In summary, the present application includes at least one of the following beneficial technical effects:

[0026] 1. The preparation method of carbonized particles provided by the present application introduces heat carrier particles to disperse polymer particles at high temperature, further raises the temperature of the obtained composite carbonized material, and performs carbonization treatment to convert it into carbonized particles. This method can control the particle size of directly carbonized particles within a few μm to dozens of μm, avoid the agglomeration of polymer particles or the formation of large-particle-size particles at high temperature, save operation steps such as grinding, avoid the risk of introducing impurities during subsequent grinding, reduce grinding energy consumption and costs, and can also control the degree of carbonization at different temperatures, saving energy and reducing material consumption during subsequent activation. It reduces the number of preparation equipment by 20%, reduces equipment investment by 25% - 30%, greatly reduces the mechanical energy consumed in production, shortens the preparation time by about 50% - 90%, saves carbonization costs by 50% - 60%, and saves grinding costs by 70% - 90%.

[0027] 2. The preparation system of carbonized particles provided by the present application is provided with a porous distribution plate that divides the carbonization fluidized bed into a low-temperature reaction zone and a high-temperature reaction zone, and can perform the first high-temperature treatment and the second high-temperature treatment on heat carrier particles, polymer particles, and composite carbonized materials respectively, realizing precise control of the temperature during the carbonization process. By adjusting the temperatures of the low-temperature reaction zone and the high-temperature reaction zone and the fluidizing gas flow rate, the entire carbonization process is made more stable and controllable.

[0028] 3. The carbonized particles obtained by the preparation method of carbonized particles provided by this application have a particle size of 5 μm - 80 μm. The carbonized particles of this particle size do not need to be ground and can directly participate in subsequent treatments such as activation to prepare porous electrode carbon, thus achieving the effect of continuous operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions of the embodiments of this application, the following will briefly introduce the drawings required for the description of the embodiments of this application. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0030] Figure 1 The flowchart of a preparation method of carbonized particles provided by an embodiment of this application is shown;

[0031] Figure 2 The structural diagram of a preparation system of carbonized particles proposed by an embodiment of this application is shown.

[0032] Explanation of the reference numerals:

[0033] 1. Carbonization fluidized bed; 11. Porous distribution plate;

[0034] 12. Low-temperature reaction zone; 121. Mixed raw material inlet;

[0035] 13. High-temperature reaction zone; 131. Fluidizing gas inlet;

[0036] 14. Overflow pipe; 15. Tail gas outlet; 16. Carbonized material outlet. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] The following will clearly and completely describe the technical solutions in the embodiments of this application with reference to the drawings in the embodiments of this application. Obviously, the described embodiments are some, but not all, of the embodiments of this application. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of this application.

[0038] In the drawings, sometimes for clarity, the sizes of the components, the thicknesses of the layers, or the areas may be exaggerated. Therefore, any implementation of this disclosure is not necessarily limited to the dimensions shown in the figures, and the shapes and sizes of the components in the figures do not reflect the true proportions. In addition, the drawings schematically show ideal examples, and any implementation of this disclosure is not limited to the shapes or values shown in the drawings.

[0039] In related technologies, in the process of preparing porous electrode carbon, there are mainly two steps: carbonization and activation, and the carbonization step is particularly important. Traditional carbonization methods can cause the precursor particles to soften and adhere at high temperatures, forming uncontrollable aggregates, which not only affects the particle size and density distribution of the carbonized particles, but also increases the difficulty and cost of subsequent grinding treatment. In addition, the formation of aggregates may also lead to the destruction of the pore structure, reducing the specific surface area and electrochemical activity of the carbonized particles. Therefore, there is an urgent need for an innovative carbonization technology that can maintain the dispersibility of precursor particles while achieving an efficient carbonization process, which is beneficial to the subsequent preparation of high-performance and low-cost porous carbon electrode materials.

[0040] See Figure 1 , Figure 1 The figure shows a flow chart of a method for preparing carbonized particles provided by an embodiment of the present application. The specific operation steps include:

[0041] S1: Under the action of fluidizing gas, place polymer particles and heat carrier particles at 200 °C - 400 °C for the first high-temperature treatment. After 0.5 h - 20 h, a composite carbonized material is obtained;

[0042] S2: Continue to raise the temperature to 500 °C - 950 °C for the second high-temperature treatment. After 0.5 h - 20 h, carbonized particles are obtained.

[0043] Among them, the polymer particles include at least one of epoxy resin, phenolic resin, urea-formaldehyde resin, unsaturated resin, and polycarbonate resin; the heat carrier particles include at least one of magnesium oxide, sodium chloride, potassium chloride, calcium chloride, calcium oxide, sodium silicate, calcium carbonate, sodium carbonate, and magnesium carbonate.

[0044] In specific implementation, by mixing polymer particles and heat carrier particles under the action of fluidizing gas and performing high-temperature treatment. This method can effectively disperse polymer particles, prevent them from softening at high temperatures and generating particularly large sticky aggregates, and is more conducive to controlling the particle size and density of carbonized particles.

[0045] By introducing heat carrier particles, the growth of particles during carbonization is inhibited, and the carbonized particles will not grow excessively; it also helps to reduce the wall sticking phenomenon of polymer particles during carbonization, making the engineering operation more convenient; the heat carrier particles also act as a heat transfer medium to accelerate heat conduction and improve the uniformity and efficiency of the carbonization process. The heat carrier particles provided by the embodiments of the present application have the advantages of high stability, small diameter, and good fluidity. Using batch preparation can increase the production capacity per unit time by 3 to 10 times.

[0046] In specific implementation, for the generated carbonized particles with heat carrier particles, by removing the heat carrier particles, porous carbonized particles can be obtained, which can reduce the activation time by 30% - 50%.

[0047] In specific implementation, the chlorides in the heat carrier particles can be used below 780 °C, and sodium silicate, carbonates, magnesium oxide, and calcium oxide can be used below 950 °C.

[0048] In some embodiments, the mass ratio of the polymer particles to the heat carrier particles is 1:(1 - 3).

[0049] In specific implementation, the mass ratio of the polymer particles to the heat carrier particles can be 1:1, 1:1.5, 1:2, 1:2.5, or 1:3.

[0050] In specific implementation, within the above mass ratio range, the number of heat carrier particles is large enough to effectively disperse the polymer particles, prevent them from aggregating into large particles during the high-temperature carbonization process, keep the carbonized particles small and uniform, and create favorable conditions for the subsequent activation step.

[0051] In some embodiments, the diameter of the polymer particles is 5 μm - 50 μm;

[0052] The diameter of the heat carrier particles is 50 μm - 200 μm.

[0053] In specific implementation, small-diameter polymer particles are prone to form finer carbonized particles, while large-diameter heat carrier particles help maintain the dispersion of these fine particles and prevent the polymer particles from agglomerating at high temperatures. The large-diameter heat carrier particles can also provide a larger surface area, which is conducive to the rapid transfer of heat. Since the polymer particles are smaller, they can absorb heat faster and undergo carbonization reactions, thereby improving the heat transfer efficiency of the entire process.

[0054] In some embodiments, the temperature of the first high-temperature treatment is 270 °C - 360 °C.

[0055] In some embodiments, the temperature of the second high-temperature treatment is 750 °C - 900 °C, and the time of the second high-temperature treatment is 3 h - 12 h.

[0056] In some embodiments, the fluidizing gas includes at least one of N2, CO, H2, Ar, He, CO2, and CH4.

[0057] In specific implementation, inert gases such as N2, Ar, and He can provide a relatively oxygen-free environment during the carbonization process to prevent the polymer particles from undergoing oxidation reactions at high temperatures.

[0058] In specific implementation, the fluidizing gas not only plays a fluidizing role but also can carry the heat carrier particles to be evenly distributed, ensuring that the polymer particles can fully contact the heat and undergo carbonization reactions.

[0059] In some embodiments, the process of the first high-temperature treatment includes:

[0060] The heat carrier particles are in a fluidized state under the action of the fluidizing gas. The polymer particles are melted and softened at a temperature of 200 °C - 400 °C and are bonded and solidified with the fluidized heat carrier particles to obtain a composite carbonized material.

[0061] Specifically, when implemented, after the heat carrier particles are in a fluidized state under the action of the fluidizing gas, it helps to achieve a more uniform distribution, further enhancing the dispersion effect of the polymer particles and avoiding their agglomeration and wall sticking phenomena at high temperatures. After the polymer particles are melted and softened, they are more likely to come into contact with and bond to the heat carrier particles, forming a more homogeneous composite carbonized material.

[0062] In some embodiments, the curing time is 1 min - 10 min. Preferably, the curing time is 3 min - 6 min.

[0063] See Figure 2 , Figure 2 which shows a preparation system for carbonized particles provided by an embodiment of the present application, specifically including:

[0064] A carbonization fluidized bed 1;

[0065] A porous distribution plate is provided inside the carbonization fluidized bed 1, and the porous distribution plate divides the carbonization fluidized bed 1 into a low-temperature reaction zone 12 and a high-temperature reaction zone 13;

[0066] The low-temperature reaction zone 12 is provided with a mixed raw material inlet 121, and the mixed raw material inlet 121 is used to introduce polymer particles and heat carrier particles into the low-temperature reaction zone 12; the low-temperature reaction zone 12 is used for performing the first high-temperature treatment on the polymer particles and the heat carrier particles to obtain a composite carbonized material;

[0067] The high-temperature reaction zone 13 is used for performing the second high-temperature treatment on the composite carbonized material to convert it into carbonized particles; the high-temperature reaction zone 13 is provided with a fluidizing gas inlet 131, and the fluidizing gas inlet 131 is used to introduce fluidizing gas into the carbonization fluidized bed 1 so that the mixed raw materials and the composite carbonized material in the carbonization fluidized bed 1 are in a fluidized state.

[0068] Specifically, when implemented, this system can prepare carbonized particles with excellent pore structures by precisely controlling the carbonization process; through the design of the carbonization fluidized bed 1 with two-stage temperatures, precise control of the carbonization process temperature is achieved, and carbonized particles suitable for activation can be directly prepared without grinding treatment, simplifying the production process and reducing production costs.

[0069] In some embodiments, temperature control devices are respectively provided on the low-temperature reaction zone 12 and the high-temperature reaction zone 13, and through a preset program, the temperatures of the low-temperature reaction zone 12 and the high-temperature reaction zone 13 are controlled to remain unchanged for a period of time.

[0070] In some embodiments, an overflow pipe 14 is provided outside the carbonization fluidized bed 1. One end of the overflow pipe 14 is connected to the low-temperature reaction zone 12 and the other end is connected to the high-temperature reaction zone 13; the composite carbonized material flows to the high-temperature reaction zone 13 through the overflow pipe 14.

[0071] During specific implementation, by providing the overflow pipe 14, it helps to quickly transport the composite carbonized material formed in the low-temperature reaction zone 12 to the high-temperature reaction zone 13. On the one hand, it avoids blockage of the low-temperature reaction zone 12, enables solid particles and fluidizing gas to continuously enter the low-temperature reaction zone 12, and ensures the smooth progress of the first high-temperature reaction; on the other hand, it accelerates the further carbonization process of the composite carbonized material and improves the reaction efficiency.

[0072] In some embodiments, a tail gas outlet 15 is further provided on the carbonization fluidized bed 1, and the fluidizing gas is discharged from the carbonization fluidized bed 1 through the tail gas outlet 15.

[0073] During specific implementation, by providing the tail gas outlet 15, the organic gas and water vapor generated in the low-temperature reaction zone 12 can escape from the carbonization fluidized bed 1 in the shortest time, without contacting the materials in the high-temperature reaction zone 13, avoiding adhesion or generation of impurities such as amorphous carbon, and being able to improve the product quality by 20 % - 30 %.

[0074] In some embodiments, a carbonized material outlet 16 is further provided on the carbonization fluidized bed 1, and the carbonized particles are discharged from the high-temperature reaction zone 13 along the carbonized material outlet 16.

[0075] During specific implementation, by providing the carbonized material outlet 16, the obtained carbonized particles can be quickly discharged from the carbonization fluidized bed 1, avoiding over-carbonization and making the carbonization process more controllable.

[0076] This application provides carbonized particles obtained by the above preparation method. The particle size of the carbonized particles is 5 μm - 80 μm. During subsequent activation treatment, no further grinding is required and it can be directly used for activation treatment to achieve the effect of continuous operation.

[0077] During specific implementation, the carbonized particles within this particle size range have higher surface reaction activity, which is beneficial to the full contact and reaction with the activator during the subsequent activation process, enabling the activator to more easily penetrate into the particle interior, react with carbon atoms to form pores, and finally form a more open and connected pore structure, improving the conductivity and capacitance performance of the porous electrode carbon of the product.

[0078] To enable those skilled in the art to more clearly understand this application, the following embodiments are now used to elaborate in detail on a method and system for preparing carbonized particles of this application.

[0079] Embodiment

[0080] Example 1

[0081] 1. A large number of heat carrier particles (magnesium oxide, particle size 50 μm - 100 μm) are loaded into the carbonization fluidized bed through the mixed raw material inlet and piled up in the high-temperature reaction zone; fluidizing gas (95% CO, 5% He) is introduced into the carbonization fluidized bed from the fluidizing gas inlet to make the heat carrier particles in a fluidized state;

[0082] 2. The temperature in the high-temperature reaction zone is raised to 920 °C - 950 °C. The fluidizing gas and the heat carrier particles pass through the porous distribution plate and enter the low-temperature reaction zone, and then form a bed layer of a certain height;

[0083] 3. Polymer particles (phenolic resin, particle size 6 μm - 9 μm) with a mass ratio of 1:1 to the heat carrier particles enter the low-temperature reaction zone of the carbonization fluidized bed along the mixed raw material inlet. The temperature is controlled at 200 °C - 300 °C for the first high-temperature treatment. After the polymer particles are rapidly melted and softened at high temperature, they are dispersed by a large number of heat carrier particles to form small composite particles (particle size 3 μm - 30 μm), and are cured after 3 minutes to obtain composite carbonized materials; a large amount of organic gases generated during the carbonization process move upward and are discharged from the carbonization fluidized bed through the tail gas outlet;

[0084] 4. As the particles are continuously fed, the composite carbonized materials in the low-temperature reaction zone increase continuously. They move downward through the porous distribution plate and the overflow pipe to reach the high-temperature reaction zone. The temperature of the high-temperature reaction zone is controlled at 920 °C - 950 °C for the second high-temperature treatment;

[0085] 5. The composite carbonized particles in the high-temperature reaction zone contact with the high-temperature gas and the high-temperature heat carrier particles and are further carbonized for 3 hours. The proportion of the carbonized particles with a particle size of 5 μm - 6 μm is greater than 90%. The obtained carbonized particles are discharged from the carbonization fluidized bed through the carbonized material outlet;

[0086] 6. By continuously introducing gas and particles, the above process can be continuously operated.

[0087] Example 2

[0088] 1. A large number of heat carrier particles (potassium oxide, particle size 100 μm - 200 μm) are loaded into the carbonization fluidized bed through the mixed raw material inlet and piled up in the high-temperature reaction zone; fluidizing gas (90% nitrogen, 10% CH4) is introduced into the carbonization fluidized bed from the fluidizing gas inlet to make the heat carrier particles in a fluidized state;

[0089] 2. The temperature in the high-temperature reaction zone is raised to 500 °C - 700 °C. The fluidizing gas and the heat carrier particles pass through the porous distribution plate and enter the low-temperature reaction zone, and then form a bed layer of a certain height;

[0090] 3. Polymer particles (90% phenolic resin + 10% urea formaldehyde resin, particle size 40 μm - 50 μm) with a mass ratio of 1:2 to the heat carrier particles are introduced into the low-temperature reaction zone of the carbonization fluidized bed along the mixed raw material inlet. The temperature is controlled at 350 °C - 400 °C for the first high-temperature treatment. After the polymer particles are rapidly melted and softened at high temperature, they are dispersed by a large number of heat carrier particles to form small composite particles (particle size 3 μm - 30 μm), and are cured after 5 minutes to obtain composite carbonized materials. A large amount of organic gases generated during the carbonization process move upward and are discharged from the carbonization fluidized bed through the tail gas outlet;

[0091] 4. As the particles are continuously fed in, the composite carbonized materials in the low-temperature reaction zone increase continuously. They move downward through the porous distribution plate and the overflow pipe respectively to reach the high-temperature reaction zone. The temperature in the high-temperature reaction zone is controlled at 500 °C - 700 °C for the second high-temperature treatment;

[0092] 5. The composite carbonized particles in the high-temperature reaction zone contact with the high-temperature gas and the high-temperature heat carrier particles, and are further carbonized for 20 hours. The proportion of the carbonized particles with a particle size of 35 μm - 45 μm is greater than 85%. The obtained carbonized particles are discharged from the carbonization fluidized bed along the carbonized material outlet;

[0093] 6. By continuously introducing gases and particles, the above process can be continuously operated.

[0094] Example 3

[0095] 1. A large number of heat carrier particles (sodium silicate, particle size 150 μm - 200 μm) are loaded into the carbonization fluidized bed through the mixed raw material inlet and piled up in the high-temperature reaction zone. Fluidizing gas (50% Ar, 50% He) is introduced into the carbonization fluidized bed from the fluidizing gas inlet to make the heat carrier particles in a fluidized state;

[0096] 2. The temperature in the high-temperature reaction zone is raised to 900 °C - 950 °C. The fluidizing gas and the heat carrier particles enter the low-temperature reaction zone through the porous distribution plate and then form a bed layer of a certain height;

[0097] 3. Polymer particles (30% phenolic resin + 30% unsaturated resin + 40% polycarbonate resin, particle size 3 μm - 12 μm) with a mass ratio of 2:3 to the heat carrier particles are introduced into the low-temperature reaction zone of the carbonization fluidized bed along the mixed raw material inlet. The temperature is controlled at 300 °C - 400 °C for the first high-temperature treatment. After the polymer particles are rapidly melted and softened at high temperature, they are dispersed by a large number of heat carrier particles to form small composite particles (particle size 3 μm - 30 μm), and are cured after 1 minute to obtain composite carbonized materials. A large amount of organic gases generated during the carbonization process move upward and are discharged from the carbonization fluidized bed through the tail gas outlet;

[0098] 4. As the feeding continues, the composite carbonized materials in the low-temperature reaction zone continuously increase and move downward through the porous distribution plate and the overflow pipe respectively to reach the high-temperature reaction zone. The temperature in the high-temperature reaction zone is controlled at 900 °C - 950 °C for the second high-temperature treatment.

[0099] 5. The composite carbonized particles in the high-temperature reaction zone contact with the high-temperature gas and the high-temperature heat carrier particles and are further carbonized for 10 hours. The proportion of the carbonized particles with a particle size of 2 μm - 8 μm is greater than 85%. The obtained carbonized particles are discharged from the carbonization fluidized bed along the carbonized material outlet.

[0100] 6. By continuously introducing gas and particles, the above process can be continuously operated.

[0101] Example 4

[0102] 1. A large amount of heat carrier particles (50% magnesium oxide + 2% calcium oxide + 10% magnesium carbonate + 38% calcium carbonate, particle size 100 μm - 150 μm) are charged into the carbonization fluidized bed through the mixed raw material inlet and stacked in the high-temperature reaction zone. Fluidizing gas (90% nitrogen, 10% H2) is introduced into the carbonization fluidized bed from the fluidizing gas inlet to make the heat carrier particles in a fluidized state.

[0103] 2. The temperature in the high-temperature reaction zone is raised to 820 °C. The fluidizing gas and the heat carrier particles enter the low-temperature reaction zone through the porous distribution plate and then form a bed layer of a certain height.

[0104] 3. Polymer particles (50% epoxy resin + 50% unsaturated resin, particle size 10 μm - 30 μm) with a mass ratio of 1:1 to the heat carrier particles enter the low-temperature reaction zone of the carbonization fluidized bed along the mixed raw material inlet. The temperature is controlled at 200 °C - 400 °C for the first high-temperature treatment. After the polymer particles are rapidly melted and softened at high temperature, they are dispersed by a large number of heat carrier particles to form small composite particles (particle size 3 μm - 30 μm) and are cured after 6 minutes to obtain composite carbonized materials. A large amount of organic gas generated during the carbonization process moves upward and is discharged from the carbonization fluidized bed through the tail gas outlet.

[0105] 4. As the feeding continues, the composite carbonized materials in the low-temperature reaction zone continuously increase and move downward through the porous distribution plate and the overflow pipe respectively to reach the high-temperature reaction zone. The temperature in the high-temperature reaction zone is controlled at 820 °C for the second high-temperature treatment.

[0106] 5. The composite carbonized particles in the high-temperature reaction zone contact with the high-temperature gas and the high-temperature heat carrier particles, and are further carbonized for 0.5 hour. The proportion of the obtained carbonized particles with a particle size of 7 μm - 25 μm is greater than 85%. The obtained carbonized particles are discharged from the carbonization fluidized bed along the carbonized material outlet;

[0107] 6. By continuously introducing gas and particles, the above process can be continuously operated.

[0108] Example 5

[0109] 1. A large amount of heat carrier particles (sodium oxide, particle size 50 μm - 70 μm) are loaded into the carbonization fluidized bed through the mixed raw material inlet and piled up in the high-temperature reaction zone; fluidizing gas (90% nitrogen, 10% H2) is introduced into the carbonization fluidized bed from the fluidizing gas inlet to make the heat carrier particles in a fluidized state;

[0110] 2. The temperature in the high-temperature reaction zone is raised to 750 °C. The fluidizing gas and the heat carrier particles pass through the porous distribution plate and enter the low-temperature reaction zone, and then form a bed layer of a certain height;

[0111] 3. Polymer particles (50% epoxy resin + 50% unsaturated resin, particle size 30 μm - 50 μm) with a mass ratio of 1:2 to the heat carrier particles enter the low-temperature reaction zone of the carbonization fluidized bed along the mixed raw material inlet. The temperature is controlled at 280 °C - 360 °C for the first high-temperature treatment. After the polymer particles are rapidly melted and softened at high temperature, they are dispersed by a large number of heat carrier particles to form small composite particles (particle size 3 μm - 30 μm, and solidified after 3 minutes to obtain composite carbonized materials); a large amount of organic gases generated during the carbonization process move upward and are discharged from the carbonization fluidized bed through the tail gas outlet;

[0112] 4. As the particles are continuously fed, the composite carbonized materials in the low-temperature reaction zone increase continuously. They move downward through the porous distribution plate and the overflow pipe respectively and reach the high-temperature reaction zone. The temperature in the high-temperature reaction zone is controlled at 750 °C for the second high-temperature treatment;

[0113] 5. The composite carbonized particles in the high-temperature reaction zone contact with the high-temperature gas and the high-temperature heat carrier particles, and are further carbonized for 12 hours. The proportion of the obtained carbonized particles with a particle size of 2 μm - 6 μm is greater than 85%. The obtained carbonized particles are discharged from the carbonization fluidized bed along the carbonized material outlet;

[0114] 6. By continuously introducing gas and particles, the above process can be continuously operated.

[0115] Example 6

[0116] 1. Load a large amount of heat carrier particles (sodium carbonate, particle size 70 μm - 150 μm) into the carbonization fluidized bed through the mixed raw material inlet, and stack them in the high-temperature reaction zone; introduce fluidizing gas (75% CO2, 30% N2) into the carbonization fluidized bed from the fluidizing gas inlet to make the heat carrier particles in a fluidized state;

[0117] 2. Raise the temperature in the high-temperature reaction zone to 800 °C - 850 °C. The fluidizing gas and the heat carrier particles pass through the porous distribution plate and enter the low-temperature reaction zone, and then form a bed layer of a certain height;

[0118] 3. Polymer particles (unsaturated resin, particle size 5 μm - 12 μm) with a mass ratio of 1:3 to the heat carrier particles enter the low-temperature reaction zone of the carbonization fluidized bed along the mixed raw material inlet. Control the temperature at 270 °C - 320 °C for the first high-temperature treatment. After the polymer particles are quickly melted and softened at high temperature, they are dispersed by a large number of heat carrier particles to form small composite particles (particle size 3 μm - 30 μm), and are cured after 1 - 3 minutes to obtain composite carbonized materials; a large amount of organic gases generated during the carbonization process move upward and are discharged from the carbonization fluidized bed through the tail gas outlet;

[0119] 4. As the feeding continues, the composite carbonized materials in the low-temperature reaction zone increase continuously. They move downward through the porous distribution plate and the overflow pipe respectively and reach the high-temperature reaction zone. The temperature in the high-temperature reaction zone is controlled at 800 °C - 850 °C for the second high-temperature treatment;

[0120] 5. The composite carbonized particles in the high-temperature reaction zone contact with the high-temperature gas and the high-temperature heat carrier particles, and are further carbonized for 6 hours. The proportion of the carbonized particles with a particle size of 4 μm - 10 μm is greater than 75%. The obtained carbonized particles are discharged from the carbonization fluidized bed along the carbonized material outlet;

[0121] 6. By continuously introducing gas and solid, the above process can be continuously operated.

[0122] In summary, a method and system for preparing carbonized particles proposed in this application have the advantage that heat carrier particles are used to effectively disperse polymer particles such as resin, avoiding softening and adhesion during carbonization, achieving the purpose of continuous operation. After the heat carrier particles are dissolved subsequently, porous carbonized particles can be formed. This method can reduce the grinding energy consumption and cost, and can also realize the control of carbonization degree at different temperatures, saving energy and reducing material consumption during subsequent activation.

[0123] Each embodiment in this specification is described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts among the embodiments can be referred to each other.

[0124] Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art can make additional changes and modifications once they learn the basic creative concept. Therefore, the appended claims are intended to be construed as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0125] Finally, it should also be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or terminal device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or terminal device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the existence of additional identical elements in the process, method, article or terminal device comprising the element.

[0126] The above has introduced in detail a method and system for preparing carbonized particles provided by the present application. Specific examples are used in this text to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those of ordinary skill in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A method for preparing carbonized particles, characterized in that, The method includes: Under the action of fluidizing gas, polymer particles and heat carrier particles are subjected to a first high-temperature treatment at 200 °C - 400 °C. The heat carrier particles are in a fluidized state under the action of the fluidizing gas. The polymer particles are melted and softened at 200 °C - 400 °C and bond and solidify with the fluidized heat carrier particles. After 0.5 h - 20 h, a composite carbonized material is obtained; The temperature is continuously raised to 500 °C - 950 °C for a second high-temperature treatment. After 0.5 h - 20 h, the carbonized particles are obtained; Among them, the polymer particles include at least one of epoxy resin, phenolic resin, urea-formaldehyde resin, unsaturated resin, and polycarbonate resin; the heat carrier particles include at least one of magnesium oxide, sodium chloride, potassium chloride, calcium chloride, calcium oxide, sodium silicate, calcium carbonate, sodium carbonate, and magnesium carbonate.

2. The preparation method of the carbonized particles according to claim 1, characterized in that, The mass ratio of the polymer particles to the heat carrier particles is 1:(1 - 3).

3. The preparation method of the carbonized particles according to claim 1, wherein The diameter of the polymer particles is 5 μm - 50 μm; The diameter of the heat carrier particles is 50 μm - 200 μm.

4. The method for preparing carbonized particles according to claim 1, wherein The temperature of the first high-temperature treatment is 270 °C - 360 °C.

5. The preparation method of the carbonized particles according to claim 1, characterized in that, The temperature of the second high-temperature treatment is 750 °C - 900 °C, and the time of the second high-temperature treatment is 3 h - 12 h.

6. The preparation method of the carbonized particles according to claim 1, characterized in that, The fluidizing gas includes at least one of N2, CO, H2, Ar, He, CO2, and CH4.

7. The preparation method of the carbonized particles according to any one of claims 1-6, characterized in that, The carbonized particles are prepared in a carbonization fluidized bed; A porous distribution plate is arranged in the carbonization fluidized bed, and the porous distribution plate divides the carbonization fluidized bed into a low-temperature reaction zone and a high-temperature reaction zone; The low-temperature reaction zone is provided with a mixed raw material inlet for introducing polymer particles and heat carrier particles into the low-temperature reaction zone; the low-temperature reaction zone is used for performing the first high-temperature treatment on the polymer particles and the heat carrier particles to obtain a composite carbonized material; The high-temperature reaction zone is used for performing the second high-temperature treatment on the composite carbonized material to convert it into carbonized particles; the high-temperature reaction zone is provided with a fluidizing gas inlet for introducing fluidizing gas into the carbonization fluidized bed to make the mixed raw materials and the composite carbonized material in the carbonization fluidized bed in a fluidized state.

8. The preparation method of the carbonized particles according to claim 7, characterized in that, An overflow pipe is arranged outside the carbonization fluidized bed. One end of the overflow pipe is connected to the low-temperature reaction zone and the other end is connected to the high-temperature reaction zone; the composite carbonized material flows to the high-temperature reaction zone through the overflow pipe; A tail gas outlet is opened on the carbonization fluidized bed, and the fluidizing gas is discharged from the carbonization fluidized bed through the tail gas outlet; A carbonized material outlet is arranged on the carbonization fluidized bed, and the carbonized particles are discharged from the high-temperature reaction zone along the carbonized material outlet.

9. The carbonized particles obtained by the preparation method of the carbonized particles according to any one of claims 1-6, characterized in that, The particle size of the carbonized particles is 5 μm - 80 μm.

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