Carbonization-activation continuous fluidized bed system and process method

Abstract

The invention provides a carbonization-activation continuous fluidized bed system and a process method, and belongs to the technical field of porous carbon materials. The process method comprises the steps of carbonization, an activation stage, oil gas treatment and waste heat recovery. In the step of carbonization, interface treatment silicon dioxide is added into phenolic resin balls, and composite phenolic resin balls are obtained; adding the composite phenolic resin balls into a carbonization fluidized bed reactor, carrying out fluidization carbonization at 640-660 DEG C in a nitrogen atmosphere for 60-70 minutes, when the temperature in the reactor is reduced to 480-500 DEG C, feeding generated semicoke into an intermediate stock bin, continuing to add the composite phenolic resin balls into the carbonization fluidized bed reactor, and carrying out carbonization in the process in a semi-continuous state; by adopting the system and the process method disclosed by the invention, stable process operation and high yield can be ensured, and the obtained activated carbon product is high in specific surface area, large in pore volume, high in tar cracking conversion rate and low in tar content at an outlet.

Description

Technical Field

[0001] This invention belongs to the field of porous carbon materials technology, specifically relating to a carbonization-activation continuous fluidized bed system and process. Background Technology

[0002] Porous carbon materials, as a type of carbon-based functional material with well-developed pore structure, abundant surface chemical groups and excellent mechanical strength, are widely used in high-temperature technology fields such as supercapacitor electrode materials, lithium-ion battery anodes, industrial gas adsorption and separation, catalyst supports and environmental remediation due to their high specific surface area, adjustable pore size distribution and excellent physicochemical stability.

[0003] With the rapid upgrading of the new energy and environmental protection industries, the market has set more stringent requirements for the performance indicators of porous carbon materials, especially high specific surface area (≥1500m²). 2 The demand for composite products with high yields, such as those with a controllable mesoporous ratio (10-15%), is increasing.

[0004] Currently, the industrial preparation of porous carbon materials mainly employs physical activation and chemical activation methods. Physical activation primarily uses water vapor or carbon dioxide as activators to etch and create pores in the carbon source at high temperatures. Chemical activation involves dehydration and carbonization reactions with reagents such as alkali metal hydroxides or phosphoric acid to construct pores. However, these processes suffer from the following technical bottlenecks: 1. High energy consumption Physical and chemical activation involve higher temperatures and are typically carried out in a segmented manner using intermittent kilns or single reactors. This necessitates intermediate cooling and reheating during the carbonization and activation processes, resulting in significant heat energy loss. 2. Tar disposal issues During the carbonization stage, carbon sources produce a large amount of heavy tar and heavy hydrocarbons. In traditional batch processes, tar is prone to condensation and adheres to the inner wall of the equipment, causing pipe blockage, equipment coking, and even production shutdown, which seriously limits the continuous and stable operation of the production line.

[0005] 3. Mismatch between carbonization and activation capacity The carbonization process is usually a rapid pyrolysis with a short reaction time, while the activation process is a slow etching process with a long time requirement. This mismatch in time scales leads to a production capacity bottleneck. The prior art CN111100656A discloses a graded recovery system and method for the pyrolysis products of carbonaceous raw materials in a fluidized bed. It mainly focuses on the recovery of pyrolysis products, but does not solve the problem of matching the production capacity and continuous connection between the two reaction processes with different durations, carbonization and activation. CN119284904A introduces an integrated biomass carbonization and activation device. However, its device structure is difficult to adapt to different atmospheres and temperature gradients required for carbonization and activation. Furthermore, it is still insufficient in the in-situ treatment of tar and comprehensive energy utilization, resulting in easy equipment blockage, high energy consumption, and difficulty in meeting the stringent requirements for material consistency in high-end fields.

[0006] 4. Lack of interface control Existing technologies mostly focus on optimizing macroscopic process parameters, neglecting the fine treatment of the microscopic interface of the carbon source surface. Carbon source powders that have not undergone interface treatment are prone to particle agglomeration during high-temperature fluidization, resulting in uneven pore structure and difficulty in constructing an ideal mesoporous network. Furthermore, how to use in-situ treatment technology to coordinate the interfacial bonding force between inorganic fillers (such as silica) and organic carbon matrix to obtain a uniform carbon layer structure during high-temperature reaction remains a technological gap that urgently needs to be addressed.

[0007] Therefore, there is an urgent need to develop a fluidized bed system that can achieve continuous carbonization-activation production, efficient tar processing, optimized energy utilization, and precise micro-interface control, in order to meet the needs of green, efficient, and large-scale production of high-quality porous carbon materials. Summary of the Invention

[0008] To address the problems existing in the prior art, this invention provides a continuous fluidized bed system and process for carbonization-activation, aiming to achieve continuous, high-efficiency and clean production of porous carbon materials. It focuses on solving key technical problems such as mismatch between carbonization and activation capacities, difficulty in tar treatment, low energy utilization, small pore size and uneven pore size of porous carbon materials.

[0009] To address the aforementioned technical problems, the present invention adopts the following technical solution: A continuous carbonization-activation process includes carbonization, activation, oil and gas treatment, and waste heat recovery steps, as detailed below: 1. Carbonization Add interface-treated silica to phenolic resin balls and stir at 320-350 rpm for 15-20 min to obtain composite phenolic resin balls. Add 50-52 kg of composite phenolic resin balls to a carbonization fluidized bed reactor in batches and carbonize at 640-660℃ under a nitrogen atmosphere for 60-70 minutes. When the temperature inside the reactor drops to 480-500℃, the resulting semi-coke is sent to an intermediate silo via gas conveying. Then, continue to add 50-52 kg of composite phenolic resin balls to the carbonization fluidized bed reactor for carbonization. The above process is maintained in a semi-continuous state. The method for preparing the interface-treated silica is as follows: A 72-75 wt% ethanol solution is heated in a water bath to 36-40℃, and the stirring speed is controlled at 250-280 rpm. While stirring, KH560 silane coupling agent is added at a rate of 0.4-0.5 g / min. After addition, the mixture is stirred for 10-15 min. Tannic acid is added, and the addition time is controlled at 10-12 min. Stirring continues for 20-25 min. Silica is then added and stirred until homogeneous. The mixture is then ultrasonically dispersed for 10-15 min at a power of 200-220 W and a frequency of 36-40 kHz. After ultrasonic dispersion, the temperature is increased to 48-52℃, and the mixture is stirred at 400-420 rpm for 2.5-3.0 h. After centrifugation, washing, and drying, the interface-treated silica is obtained. The mass ratio of the interface-treated silica to the phenolic resin balls is 0.3-0.5:100; The phenolic resin balls were purchased from Zhejiang Zili Polymer Chemical Materials Co., Ltd., and the brand name is SS-8223. The carbonized fluidized bed reactor has a capacity of 300L and is made of 310S stainless steel. In the method for preparing interface-treated silica, the mass ratio of the ethanol solution, kH560 silane coupling agent, tannic acid and silica is 100:5-7:3-3.5:15-20. The silicon dioxide has a particle size of 20-30 nm.

[0010] 2. Activation stage When the semi-coke accumulates to 300-305 kg in the intermediate silo, it is fed into the activation fluidized bed reactor by gas conveying and activated at 945-955℃ in a steam atmosphere for 600-750 minutes to obtain activated carbon product. The activated fluidized bed reactor has a capacity of 1500L and is made of 310S stainless steel. The mass ratio of water vapor to semi-coke is 1.5-3:1.

[0011] 3. Oil and gas treatment The tail gas of the carbonized fluidized bed reactor is separated into oil and gas. The separated heavy tar is catalytically cracked into light gas under the action of Ni-based catalyst. The cracking temperature is 795-805℃. The main components of the light gas are H2, CO and CH4. Part of it is recycled as auxiliary fuel for activating the fluidized bed. The mass ratio of heavy tar to Ni-based catalyst is 1:0.3-0.4; The Ni-based catalyst was purchased from Dalian Longxiang Weihua Chemical Co., Ltd., and its brand name is Ni-ZSM-5-ATP.

[0012] 4. Waste heat recovery High-temperature oil and gas generate 0.45-0.55MPa saturated steam through a waste heat boiler, part of which is used for preheating the activator and part for drying the raw materials; The high-temperature oil and gas has a temperature of 500-510℃ and comes from the tail gas of the carbonized fluidized bed reactor and the tail gas of the activated fluidized bed reactor.

[0013] A continuous fluidized bed system for carbonization and activation includes a carbonization fluidized bed reactor, an intermediate silo, an activation fluidized bed reactor, an oil and gas processing unit, and a material conveying device. It adopts a dual fluidized bed series structure and is connected by an intermediate silo for buffering, so as to realize the continuous carbonization and activation and the matching of production capacity.

[0014] Compared with the prior art, the present invention has achieved the following beneficial effects: 1. Using the process method of this invention, after 120 hours of continuous operation, the system operates continuously and stably without tar blockage problems, and the yield is 15-20%; 2. The activated carbon product obtained by the process method of the present invention has a specific surface area of ​​1785-2043 m². 2 / g, total pore volume is 0.79-0.95cm³ 3 / g, of which mesoporous content is 7-15%, and the product quality is uniform and stable; 3. Using the process method of this invention, in the oil and gas treatment step, the tar cracking conversion rate is >95%, and the tar content in the outlet gas is less than 45 mg / Nm³. 3 . Attached Figure Description

[0015] Figure 1 This is a flowchart of the carbonization-activation process of the present invention; Figure 2 This is a pore size distribution diagram of the activated carbon product prepared in Example 1. Detailed Implementation

[0016] To provide a clearer understanding of the technical features, objectives, and effects of the present invention, specific embodiments of the present invention are now described.

[0017] like Figure 1As shown, carbonaceous raw materials from the raw material silo 1 enter the carbonization fluidized bed reactor 2 from the left. The carbonized semi-coke is then sent to the intermediate material silo 4 under positive pressure via the first conveying device 13 for temporary storage, and then sent to the activation fluidized bed reactor 3 under positive pressure via the second conveying device 14 for activation. The oil and gas generated during carbonization enter the oil and gas separator 5 via the filter heating device 12. The separated heavy tar enters the tar catalytic cracking device 6 for processing. The light components are discharged after passing through the condensation recovery device 8, and the combustible gas is stored in the light gas storage tank 9 for reuse. The waste heat from the oil and gas and the activation tail gas is used by the waste heat recovery device 7 to preheat the activator preheater 10 and the raw material silo 1. Finally, the activated carbon product is discharged from the activation bed and enters the product cooling collection silo 11.

[0018] Example 1 1. Carbonization Interface-treated silica was added to phenolic resin balls and stirred at 320 rpm for 15 min to obtain composite phenolic resin balls. The composite phenolic resin balls were added to a carbonization fluidized bed reactor in batches of 50 kg and carbonized at 640 °C under a nitrogen atmosphere for 60 min. When the temperature inside the reactor dropped to 480 °C, the semi-coke produced was sent to an intermediate silo by gas conveying. Then, 50 kg of composite phenolic resin balls were added to the carbonization fluidized bed reactor for carbonization. The above process was kept in a semi-continuous state. The method for preparing the interface-treated silica is as follows: 100g of 72wt% ethanol solution is heated to 36℃ in a water bath, and the stirring speed is controlled at 250rpm. 5g of KH560 silane coupling agent is added while stirring at a rate of 0.4g / min. After the addition is complete, the mixture is stirred for 10min. Then, 3g of tannic acid is added, and the addition time is controlled at 10min. The mixture is stirred for another 20min. Finally, 15g of silica is added and stirred until homogeneous. The mixture is then ultrasonically dispersed for 10min at a power of 200W and a frequency of 36kHz. After ultrasonic dispersion, the temperature is increased to 48℃, and the mixture is stirred at 400rpm for 2.5h. After centrifugation, washing, and drying, the interface-treated silica is obtained. The mass ratio of the phenolic resin balls to the interface-treated silica is 100:0.3; The phenolic resin balls were purchased from Zhejiang Zili Polymer Chemical Materials Co., Ltd., and the brand name is SS-8223. The carbonized fluidized bed reactor has a capacity of 300L and is made of 310S stainless steel. The silicon dioxide has a particle size of 20 nm.

[0019] 2. Activation stage When the semi-coke accumulates to 300 kg in the intermediate silo, it is fed into the activation fluidized bed reactor by gas conveying and activated for 600 minutes at 945℃ in a steam atmosphere to obtain activated carbon product. The activated fluidized bed reactor has a capacity of 1500L and is made of 310S stainless steel. The mass ratio of water vapor to semi-coke is 1.5:1.

[0020] 3. Oil and gas treatment The tail gas of the carbonized fluidized bed reactor is separated into oil and gas. The separated heavy tar is catalytically cracked into light gas under the action of Ni-based catalyst. The cracking temperature is 795℃. The main components of the light gas are H2, CO and CH4. Part of it is recycled as auxiliary fuel for activating the fluidized bed. The mass ratio of heavy tar to Ni-based catalyst is 1:0.3. The Ni-based catalyst was purchased from Dalian Longxiang Weihua Chemical Co., Ltd., and its brand name is Ni-ZSM-5-ATP.

[0021] 4. Waste heat recovery High-temperature oil and gas generate 0.45MPa saturated steam through a waste heat boiler, part of which is used for preheating the activator and part for drying the raw materials; The high-temperature oil and gas has a temperature of 500℃ and comes from the tail gas of the carbonized fluidized bed reactor and the tail gas of the activated fluidized bed reactor.

[0022] The pore size distribution diagram of the activated carbon product obtained in Example 1 is shown in the attached figure in the instruction manual. Figure 2 ; Using the process method of Example 1, after continuous operation for 120 hours, the following results were obtained: The system operated continuously and stably without tar blockage issues, achieving a yield of 15%; the obtained activated carbon product had a specific surface area of ​​1785 m². 2 / g, total pore volume is 0.79cm³ 3 / g, of which mesoporous content is 15%, and the product quality is uniform and stable; In the oil and gas processing steps, the tar cracking conversion rate is >95%, and the tar content in the outlet gas is less than 45 mg / Nm³. 3 .

[0023] Example 2 1. Carbonization Interface-treated silica was added to phenolic resin balls and stirred at 340 rpm for 180 min to obtain composite phenolic resin balls. The composite phenolic resin balls were added to a carbonization fluidized bed reactor in batches of 50 kg and carbonized at 650 °C under a nitrogen atmosphere for 65 min. When the temperature inside the reactor dropped to 490 °C, the semi-coke produced was sent to an intermediate silo by gas conveying. Then, 50 kg of composite phenolic resin balls were added to the carbonization fluidized bed reactor for carbonization. The above process was kept in a semi-continuous state. The method for preparing the interface-treated silica is as follows: 100g of 74wt% ethanol solution is heated to 38℃ in a water bath, and the stirring speed is controlled at 270rpm. 6g of KH560 silane coupling agent is added while stirring at a rate of 0.45g / min. After addition, the mixture is stirred for 13min. Then, 3.2g of tannic acid is added over a time of 12min. The mixture is stirred for another 23min. Finally, 18g of silica is added and stirred until homogeneous. The mixture is then ultrasonically dispersed for 13min at a power of 210W and a frequency of 38kHz. After ultrasonic dispersion, the temperature is increased to 50℃, and the mixture is stirred at 410rpm for 2.8h. After centrifugation, washing, and drying, the interface-treated silica is obtained. The mass ratio of the phenolic resin balls to the interface-treated silica is 100:0.4; The phenolic resin balls were purchased from Zhejiang Zili Polymer Chemical Materials Co., Ltd., and the brand name is SS-8223. The carbonized fluidized bed reactor has a capacity of 300L and is made of 310S stainless steel. The silicon dioxide has a particle size of 25 nm.

[0024] 2. Activation stage When the semi-coke accumulates to 303 kg in the intermediate silo, it is fed into the activation fluidized bed reactor by gas conveying and activated for 700 minutes at 950°C in a steam atmosphere to obtain activated carbon product. The activated fluidized bed reactor has a capacity of 1500L and is made of 310S stainless steel. The mass ratio of water vapor to semi-coke is 2:1.

[0025] 3. Oil and gas treatment The tail gas of the carbonized fluidized bed reactor is separated into oil and gas. The separated heavy tar is catalytically cracked into light gas under the action of Ni-based catalyst at a cracking temperature of 800℃. The main components of the light gas are H2, CO and CH4, and part of it is recycled as auxiliary fuel for activating the fluidized bed. The mass ratio of heavy tar to Ni-based catalyst is 1:0.4. The Ni-based catalyst was purchased from Dalian Longxiang Weihua Chemical Co., Ltd., and its brand name is Ni-ZSM-5-ATP.

[0026] 4. Waste heat recovery High-temperature oil and gas generate 0.50MPa saturated steam through a waste heat boiler, part of which is used for preheating the activator and part for drying the raw materials; The high-temperature oil and gas has a temperature of 505℃ and comes from the tail gas of the carbonized fluidized bed reactor and the tail gas of the activated fluidized bed reactor.

[0027] Using the process method of Example 2, after continuous operation for 120 hours, the following results were obtained: The system operated continuously and stably without tar blockage issues, achieving a yield of 20%; the obtained activated carbon product had a specific surface area of ​​1800 m². 2 / g, total pore volume is 0.82cm³ 3 / g, of which mesoporous content is 7%, and the product quality is uniform and stable; In the oil and gas processing steps, the tar cracking conversion rate is >95%, and the tar content in the outlet gas is less than 45 mg / Nm³. 3 .

[0028] Example 3 1. Carbonization Interface-treated silica was added to phenolic resin balls and stirred at 350 rpm for 20 min to obtain composite phenolic resin balls. The composite phenolic resin balls were added to a carbonization fluidized bed reactor in batches of 52 kg and carbonized at 660 °C under a nitrogen atmosphere for 70 min. When the temperature inside the reactor dropped to 500 °C, the semi-coke produced was sent to an intermediate silo by gas conveying. Then, 52 kg of composite phenolic resin balls were added to the carbonization fluidized bed reactor for carbonization. The above process was kept in a semi-continuous state. The method for preparing the interface-treated silica is as follows: 100g of 75wt% ethanol solution is heated to 40℃ in a water bath, and the stirring speed is controlled at 280rpm. 7g of KH560 silane coupling agent is added while stirring at a rate of 0.5g / min. After the addition is complete, the mixture is stirred for 15min. Then, 3.5g of tannic acid is added over a time of 12min. The mixture is stirred for another 25min. Finally, 20g of silica is added and stirred until homogeneous. The mixture is then ultrasonically dispersed for 15min at a power of 220W and a frequency of 40kHz. After ultrasonic dispersion, the temperature is increased to 52℃, and the mixture is stirred at 420rpm for 3.0h. After centrifugation, washing, and drying, the interface-treated silica is obtained. The mass ratio of the phenolic resin balls to the interface-treated silica is 100:0.5; The phenolic resin balls were purchased from Zhejiang Zili Polymer Chemical Materials Co., Ltd., and the brand name is SS-8223. The carbonized fluidized bed reactor has a capacity of 300L and is made of 310S stainless steel. The silicon dioxide has a particle size of 30 nm.

[0029] 2. Activation stage When the semi-coke accumulates to 305 kg in the intermediate silo, it is fed into the activation fluidized bed reactor by gas conveying and activated for 750 minutes at 955°C in a steam atmosphere to obtain activated carbon product. The activated fluidized bed reactor has a capacity of 1500L and is made of 310S stainless steel. The mass ratio of water vapor to semi-coke is 3:1.

[0030] 3. Oil and gas treatment The tail gas of the carbonized fluidized bed reactor is separated into oil and gas. The separated heavy tar is catalytically cracked into light gas under the action of Ni-based catalyst at a cracking temperature of 805℃. The main components of the light gas are H2, CO and CH4, and part of it is recycled as auxiliary fuel for activating the fluidized bed. The mass ratio of heavy tar to Ni-based catalyst is 1:0.4. The Ni-based catalyst was purchased from Dalian Longxiang Weihua Chemical Co., Ltd., and its brand name is Ni-ZSM-5-ATP.

[0031] 4. Waste heat recovery High-temperature oil and gas generate 0.55MPa saturated steam through a waste heat boiler, part of which is used for preheating the activator and part for drying the raw materials; The high-temperature oil and gas has a temperature of 510℃ and comes from the tail gas of the carbonized fluidized bed reactor and the tail gas of the activated fluidized bed reactor.

[0032] Using the process method of Example 3, after continuous operation for 120 hours, the following results were obtained: The system operated continuously and stably without tar blockage issues, achieving a yield of 16%; the obtained activated carbon product had a specific surface area of ​​2043 m². 2 / g, total pore volume is 0.95cm³ 3 / g, of which mesoporous content is 11%, and the product quality is uniform and stable; In the oil and gas processing steps, the tar cracking conversion rate is >95%, and the tar content in the outlet gas is less than 45 mg / Nm³. 3 .

[0033] Comparative Example The changes made in Example 3 are as follows: In the carbonization step, phenolic resin balls are replaced with coconut shells in equal amounts; the preparation method of interface-treated silica is omitted, and interface-treated silica is replaced with untreated silica in equal amounts. The rest of the operations are exactly the same.

[0034] Using a comparative process, after 120 hours of continuous operation, the following results were obtained: The system's operational stability deteriorated, with localized tar adhesion and particle agglomeration occurring, resulting in a yield of 13%; the obtained activated carbon product had a specific surface area of ​​1627 m². 2 / g, total pore volume is 0.72cm³ 3 / g, of which mesoporous content is 5%; In the oil and gas processing steps, the tar cracking conversion rate is <90%, and the tar content in the outlet gas is higher than 80 mg / Nm³. 3 .

[0035] In this invention, the silica undergoes interface treatment during the carbonization process. Specifically, it is treated with a mixture of KH560 silane coupling agent and tannic acid. The silanol groups in KH560 hydrolyze to form hydroxyl groups, which bind firmly to the hydroxyl groups of silica, adhering to the silica surface. The silane coupling agent forms an organic coating layer on the silica surface, preventing particle agglomeration. The epoxy group at the other end of the silane coupling agent can bind to the surface of phenolic resin balls and coconut shells. Tannic acid, as a natural polyphenol compound, contains a large number of phenolic hydroxyl groups, which can bind to both phenolic resin balls and the epoxy groups of the silane coupling agent on the silica surface, promoting the dispersion of silica in the carbon source. The interface-treated silica, as a dopant, exhibits high-temperature inertness and structural stability, and also possesses fluidization properties. It does not melt or decompose during high-temperature carbonization and does not react with carbon, maintaining particle size distribution. In terms of morphology, phenolic resin spheres form a carbon matrix during pyrolysis and polycondensation. Silica can form mesoporous sites, and its excellent thermal conductivity allows for rapid dispersion of reaction heat, reducing the temperature difference between the inside and outside of the particles, resulting in a more uniform semi-coke structure. During the activation stage, the stable mesoporous structure provides efficient mass transfer channels, allowing water vapor to quickly enter the particle interior, resulting in more uniform activation etching and avoiding the phenomenon of "excessive ablation of the outer shell and insufficient activation of the interior." This significantly increases the specific surface area and improves the total pore volume. Furthermore, silica acts as a skeletal support during activation, preventing the collapse of pores at high temperatures and ensuring the integrity of the pores, resulting in high porosity and uniform quality of the activated carbon. This invention uses interface-treated silica, which can reduce side reactions, reduce the generation of heavy tar, improve the quality of semi-coke, increase the catalytic cracking conversion rate of tar, reduce tar content, avoid tar blockage, and ensure stable operation of the process. This invention employs a dual-fluidized bed series structure, connected by an intermediate silo for buffering, to achieve continuous carbonization and activation with matching capacity. It integrates tar catalytic cracking and waste heat recovery units to realize tar resource utilization and system energy optimization. Based on the reaction characteristics of short carbonization time and long activation time, the capacity of the carbonization fluidized bed is designed to be 10%-30% of that of the activation fluidized bed. An intermediate silo (7-15 times the volume of the carbonization bed) provides material buffering and continuous supply, solving the capacity mismatch problem. Furthermore, combined with a high-efficiency tar treatment system, the oil and gas generated during carbonization are first separated into heavy tar and medium-light tar by an oil-gas separator. The heavy tar is introduced into a tar catalytic cracker for cracking into light gases (such as H2, CO, CH4) and a small amount of activated carbon. The light gases are reused as system fuel or fluidizing medium. The system uses a waste heat recovery device to preheat the activator or raw materials with the waste heat from the high-temperature oil and gas and activation tail gas, significantly reducing energy consumption and producing activated carbon products with different specific surface areas and pore sizes.

[0036] In the comparative example, silica was directly mixed with coconut shell for carbonization. Silica without interface treatment exhibited strong agglomeration forces, easily agglomerating on the coconut shell surface and failing to form a uniformly dispersed mesoporous template. This resulted in a disordered mesoporous structure after activation, with low surface area and pore volume. Furthermore, under the high temperature and strong airflow of the fluidized bed, silica easily detached from the coconut shell and was carried away by the exhaust gas, failing to continuously exert its doping effect. The coconut shell also melted and softened more during pyrolysis, resulting in more significant shrinkage. Compared to phenolic resin balls, it was more prone to adhesion and uneven fluidization within the fluidized bed, making it difficult for water vapor to uniformly penetrate the interior of the coconut shell-based semi-coke. This led to excessive external ablation and insufficient internal activation, significantly reducing specific surface area, total pore volume, and mesoporous ratio. Ultimately, this also resulted in a significant increase in the generation of heavy tar, a subsequent decrease in tar catalytic cracking rate, an increase in outlet tar content, and system blockage, making long-term stable operation impossible.

[0037] Unless otherwise stated, all percentages used in this invention are mass percentages.

[0038] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A continuous carbonization-activation process, characterized in that, This includes carbonization, activation, oil and gas treatment, and waste heat recovery steps. The carbonization step involves adding interface-treated silica to phenolic resin balls to obtain composite phenolic resin balls; adding the composite phenolic resin balls to a carbonization fluidized bed reactor and carbonizing them at 640-660°C under a nitrogen atmosphere for 60-70 minutes; and when the temperature inside the reactor drops to 480-500°C, the resulting semi-coke is sent to an intermediate silo, and the composite phenolic resin balls are continued to be added to the carbonization fluidized bed reactor for carbonization. The above process is maintained in a semi-continuous state. The method for preparing the interface-treated silica is as follows: heat the ethanol solution to 36-40℃, add kH560 silane coupling agent and tannic acid, stir evenly, add silica, and ultrasonically disperse for 10-15 min. After ultrasonic dispersion, heat to 48-52℃ and stir for 2.5-3.0 h to obtain interface-treated silica.

2. The continuous carbonization-activation process method according to claim 1, characterized in that, In the carbonization step, the mass ratio of the interface-treated silica to the phenolic resin balls is 0.3-0.5:

100. The carbonized fluidized bed reactor has a capacity of 300L and is made of 310S stainless steel.

3. The continuous carbonization-activation process according to claim 1, characterized in that, In the method for preparing interface-treated silica, the mass ratio of the ethanol solution, kH560 silane coupling agent, tannic acid and silica is 100:5-7:3-3.5:15-20. The silicon dioxide has a particle size of 20-30 nm.

4. The continuous carbonization-activation process according to claim 1, characterized in that, The activation stage involves the following steps: when the semi-coke accumulates to 300-305 kg in the intermediate silo, it is fed into the activation fluidized bed reactor via gas conveying and activated at 945-955℃ in a steam atmosphere for 600-750 minutes to obtain activated carbon product. The activated fluidized bed reactor has a capacity of 1500L and is made of 310S stainless steel. The mass ratio of water vapor to semi-coke is 1.5-3:

1.

5. The continuous carbonization-activation process according to claim 1, characterized in that, The oil and gas treatment step is to separate the carbonized oil and gas from the tail gas of the carbonized fluidized bed reactor. The separated heavy tar is catalytically cracked into light gas under the action of Ni-based catalyst. The cracking temperature is 795-805℃. The main components of the light gas are H2, CO and CH4. Part of it is recycled as auxiliary fuel for activating the fluidized bed. The mass ratio of heavy tar to Ni-based catalyst is 1:0.3-0.

4.

6. The continuous carbonization-activation process according to claim 1, characterized in that, The waste heat recovery step involves generating 0.45-0.55MPa saturated steam from high-temperature oil and gas through a waste heat boiler, part of which is used for preheating the activator and part for drying the raw materials. The high-temperature oil and gas has a temperature of 500-510℃ and comes from the tail gas of the carbonized fluidized bed reactor and the tail gas of the activated fluidized bed reactor.

7. A continuous fluidized bed system for carbonization-activation, characterized in that, The system employs a dual fluidized bed series structure, with intermediate silos acting as buffers to achieve continuous carbonization and activation, and to match production capacity.

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