High-temperature bamboo charcoal preparation and flue gas recycling process capable of utilizing all components of bamboo sawdust

Abstract

The invention relates to the technical field of bamboo sawdust, and discloses a high-temperature bamboo charcoal preparation and flue gas recycling process for all-component utilization of bamboo sawdust, which realizes all-component efficient utilization of bamboo sawdust, improves the resource utilization rate, not only produces high-quality bamboo charcoal, but also realizes comprehensive utilization of flue gas through a multi-stage separation and deep processing technology. Wood vinegar, wood tar (containing aromatic compounds such as anthracene and naphthalene) and combustible gas are recycled from the smoke, graded conversion of components such as cellulose and hemicellulose in the bamboo sawdust is achieved, and resource waste is avoided. The problem that a traditional process only focuses on bamboo charcoal production and neglects byproduct recovery is solved, and the utilization rate of the bamboo scraps is increased to the maximum. In the bamboo sawdust pretreatment stage, through fine screening, cleaning and smashing, the uniformity of the raw materials is ensured, and a stable basis is provided for subsequent carbonization. High-temperature directional carbonization is combined with water vapor activation, so that the bamboo charcoal forms a rich microporous structure, the specific surface area is remarkably increased, the pH value of the finished bamboo charcoal is stabilized at 6.5-7.0, and the bamboo charcoal can be directly applied to sewage treatment, air purification and other scenes.

Description

Technical Field

[0001] This invention relates to the field of bamboo shavings technology, specifically to a high-temperature bamboo charcoal preparation and flue gas resource utilization process that utilizes all components of bamboo shavings. Background Technology

[0002] Bamboo shavings, a major waste product from bamboo processing, are produced in huge quantities annually. Currently, they are mostly disposed of by incineration or landfill, which not only wastes resources but also easily causes environmental pollution problems.

[0003] Traditional bamboo charcoal production processes focus primarily on the production of bamboo charcoal itself, which has the following limitations: First, the energy utilization rate is low during high-temperature carbonization, and the direct emission of flue gas leads to serious heat loss; second, the tar, volatile organic compounds (VOCs), and combustible gases contained in the flue gas are not effectively recovered, which pollutes the environment and wastes resources; third, bamboo charcoal products have limited performance and fail to achieve graded utilization of components such as cellulose and hemicellulose in bamboo chips.

[0004] The existing high-temperature bamboo charcoal preparation process has obvious limitations: First, the raw material pretreatment is crude, and the utilization rate is not improved through fine screening and crushing, resulting in uneven bamboo charcoal quality; second, the flue gas treatment only stops at basic dust removal and does not recover high-value-added by-products such as wood tar and wood vinegar; third, the energy utilization is inefficient, and the waste heat in the drying and carbonization process is not recycled, relying on external energy input.

[0005] Therefore, it is necessary to provide a high-temperature bamboo charcoal preparation and flue gas resource utilization process that utilizes all components of bamboo chips to solve the above problems. Summary of the Invention

[0006] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a high-temperature bamboo charcoal preparation and flue gas resource utilization process that utilizes all components of bamboo chips. This process has good quality, high resource utilization rate, and conforms to the concept of green development.

[0007] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: a high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips, comprising the following steps: S1: Bamboo Shavings Pretreatment After removing impurities from the bamboo shavings through an 18-20 mesh vibrating screen, the raw bamboo shavings are rinsed 3-4 times with running water to remove surface dust. Then, they are placed in a 60-65℃ hot air drying oven to dry for 3-4 hours until the moisture content is 8-10%. Finally, they are crushed by a pulverizer to obtain pre-treated bamboo shavings. S2: High-temperature directional carbonization The pretreated bamboo chips are fed into a continuous vertical carbonization furnace (5m³ volume, made of high-temperature resistant stainless steel), and nitrogen gas (flow rate 0.8m³ / h) is introduced to isolate oxygen for protection. The temperature is increased according to the following procedure: First stage: Heat at a rate of 5℃ / min and hold for 1.5 hours; Second stage: Continue to heat to 400-600℃ at a rate of 8℃ / min, and hold for 2 hours; Third stage: Continue to heat to 800-1000℃ at a rate of 12℃ / min, and hold for 2 hours; Cooling stage: After carbonization, the bamboo charcoal is slowly cooled under nitrogen protection (to prevent oxidation) to obtain coarse bamboo charcoal (containing a small amount of non-volatile tar and wood vinegar residue). S3: Flue Gas Collection and Separation The flue gas produced during the carbonization process (mainly composed of wood tar vapor, wood vinegar vapor, ...) Combustible gases and water vapor are introduced into a multi-stage condensation system through high-temperature resistant pipes (≥1000℃ tolerance): Preheating section: Removes large particles of dust (such as incompletely crushed bamboo shavings) from the flue gas under heating conditions. First-stage condenser (60℃): Separates crude tar (density 1.0~1.2g / cm³, containing anthracene and naphthalene aromatic compounds); Secondary condenser (25℃): Condensation yields crude wood vinegar (pH 3.5~4.0, main components are acetic acid, propionic acid and phenols); Non-condensable gas treatment: Residual non-condensable gases (mainly...) (And a small amount of nitrogen) is removed by spraying sodium hydroxide solution in the desulfurization tower. After purification, it is temporarily stored in a gas storage tank; S4: Bamboo Charcoal Post-treatment The coarse bamboo charcoal is crushed to 1-3mm and placed in an activation furnace. It is activated in a steam atmosphere (flow rate 0.5kg / h) at 830-850℃ (the steam reacts with the carbon on the bamboo charcoal surface to generate micropores, increasing the specific surface area). It is then cooled to room temperature and washed with deionized water until the pH reaches 6.5-7.0 (to remove residual acid and alkali impurities). Finally, it is dried at 102-105℃ for 2-3 hours to obtain the finished bamboo charcoal. Optional applications: The finished bamboo charcoal is mixed with bentonite at a mass ratio of 9:1 and pressed into columnar charcoal with a diameter of 5cm and a length of 10cm under a pressure of 20MPa (suitable for wastewater treatment or air purification). S5: Deep utilization of flue gas Wood vinegar: After the crude wood vinegar is allowed to stand and separate into layers (to remove impurities at the bottom), it is filtered through a 0.45μm filter membrane and then vacuum distilled at 60℃ and -0.08MPa. The fraction at 102-105℃ is collected to obtain refined wood vinegar. Wood tar: Crude tar is distilled under reduced pressure at -0.09 MPa (220-250℃ range) to separate high-value-added aromatic compounds such as anthracene and naphthalene; Combustible gas: The purified gas in the gas storage tank is pressurized and reused as the carrier gas in the carbonization furnace (replacing part of the nitrogen), reducing external energy consumption.

[0008] Furthermore, the particle size of the pulverized material in S1 is 3-5 mm.

[0009] Furthermore, the first stage heating temperature in S2 is 200-300℃.

[0010] Furthermore, the cooling temperature in the S2 cooling stage is reduced to 115-120°C.

[0011] Furthermore, the heating temperature in S3 is 195-200℃.

[0012] Furthermore, the mass fraction of sodium hydroxide solution in S3 is 5-7%.

[0013] Furthermore, the activation time in S4 is 1-1.5 hours.

[0014] Furthermore, the pressurization pressure of the combustible gas in S5 is 0.26-0.3 MPa.

[0015] (iii) Beneficial technical effects This invention achieves efficient utilization of all components of bamboo shavings, improving resource utilization. It not only produces high-quality bamboo charcoal but also recovers wood vinegar, wood tar (containing aromatic compounds such as anthracene and naphthalene), and combustible gases from flue gas through multi-stage separation and deep processing technology. This process enables the graded conversion of components such as cellulose and hemicellulose in bamboo shavings, avoiding resource waste. It solves the problem of traditional processes focusing solely on bamboo charcoal production while neglecting byproduct recovery, maximizing the utilization rate of bamboo shavings. In the bamboo shavings pretreatment stage, fine screening, washing, and crushing ensure the uniformity of raw materials, providing a stable foundation for subsequent carbonization. High-temperature directional carbonization combined with steam activation results in a rich microporous structure in the bamboo charcoal, significantly increasing its specific surface area. The finished bamboo charcoal has a stable pH value of 6.5-7.0, allowing for direct application in wastewater treatment, air purification, and other scenarios.

[0016] The flue gas undergoes a multi-stage condensation system to separate crude tar and crude wood vinegar, which are then refined through processes such as vacuum distillation to obtain high-value-added products (such as refined wood vinegar, anthracene, and naphthalene compounds), thus realizing the transformation of pollutants into resources. The purified combustible gas ( The nitrogen gas is recycled back to the carbonization furnace as carrier gas, replacing part of the nitrogen gas, reducing external energy input and lowering production energy consumption; at the same time, the desulfurization tower removes nitrogen. This avoids environmental pollution caused by direct emissions of flue gas. A continuous vertical carbonization furnace is used, combined with a precise temperature control program (three-stage heating rate and holding time) and nitrogen-protected cooling to ensure the continuity and stability of bamboo charcoal production and reduce batch variations. The recycling of by-products (wood vinegar, tar derivatives, and combustible gases) increases the economic value of the process and reduces the unit production cost of bamboo charcoal. This method replaces traditional bamboo chip incineration or landfill disposal, reducing carbon emissions and solid waste pollution, aligning with the concept of green and low-carbon development. Detailed Implementation

[0017] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 A high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips includes the following steps: S1: Bamboo Shavings Pretreatment After removing impurities by passing the bamboo shavings through an 18-mesh vibrating screen, the raw material is rinsed three times with running water to remove surface dust. Then, it is placed in a 60℃ hot air drying oven to dry for 3 hours until the moisture content is 8%. Finally, it is crushed to 3mm by a pulverizer to obtain pre-treated bamboo shavings. S2: High-temperature directional carbonization The pretreated bamboo chips are fed into a continuous vertical carbonization furnace (5m³ volume, made of high-temperature resistant stainless steel), and nitrogen gas (flow rate 0.8m³ / h) is introduced to isolate oxygen for protection. The temperature is increased according to the following procedure: First stage: Heat to 200℃ at a rate of 5℃ / min and hold for 1.5 hours; Second stage: Continue to heat to 400℃ at a rate of 8℃ / min, and hold for 2 hours; Third stage: Continue to heat to 800℃ at a rate of 12℃ / min, and hold for 2 hours; Cooling stage: After carbonization, the bamboo charcoal is slowly cooled to 115°C under nitrogen protection (to prevent oxidation) to obtain coarse bamboo charcoal (containing a small amount of non-volatile tar and wood vinegar residue). S3: Flue Gas Collection and Separation The flue gas produced during the carbonization process (mainly composed of wood tar vapor, wood vinegar vapor, ...) Combustible gases and water vapor are introduced into a multi-stage condensation system through high-temperature resistant pipes (≥1000℃ tolerance): Preheating section: Removes large particles of dust (such as incompletely crushed bamboo shavings) from the flue gas by heating at 195℃. First-stage condenser (60℃): Separates crude tar (density 1.0 g / cm³, containing anthracene and naphthalene aromatic compounds); Secondary condenser (25℃): Condensation yields crude wood vinegar (pH 3.5, main components are acetic acid, propionic acid and phenols); Non-condensable gas treatment: Residual non-condensable gases (mainly...) (And a small amount of nitrogen) is removed by spraying in a desulfurization tower (using a 5% sodium hydroxide solution). After purification, it is temporarily stored in a gas storage tank; S4: Bamboo Charcoal Post-treatment The coarse bamboo charcoal is crushed to 1mm and placed in an activation furnace. It is activated for 1 hour in a steam atmosphere at 830℃ (flow rate 0.5kg / h) (the steam reacts with the carbon on the surface of the bamboo charcoal to generate micropores, increasing the specific surface area). Then it is cooled to room temperature. It is washed with deionized water until pH 6.5 (to remove residual acid and alkali impurities). Finally, it is dried at 102℃ for 2 hours to obtain the finished bamboo charcoal. Optional applications: The finished bamboo charcoal is mixed with bentonite at a mass ratio of 9:1 and pressed into columnar charcoal with a diameter of 5cm and a length of 10cm under a pressure of 20MPa (suitable for sewage treatment or air purification). S5: Deep utilization of flue gas Wood vinegar: After the crude wood vinegar is allowed to stand and separate into layers (to remove impurities at the bottom), it is filtered through a 0.45μm filter membrane and then vacuum distilled at 60℃ and -0.08MPa. The fraction at 102℃ is collected to obtain refined wood vinegar. Wood tar: Crude tar is distilled under reduced pressure at -0.09 MPa (220℃ range) to separate high-value-added aromatic compounds such as anthracene and naphthalene; Combustible gas: The purified gas in the gas storage tank is pressurized to 0.26MPa and reused as the carrier gas for the carbonization furnace (replacing part of the nitrogen), reducing external energy consumption.

[0019] Example 2 A high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips includes the following steps: S1: Bamboo Shavings Pretreatment After removing impurities by passing the bamboo shavings through a 20-mesh vibrating screen, the raw material is rinsed four times with running water to remove surface dust. Then, it is placed in a 65℃ hot air drying oven to dry for 4 hours until the moisture content is 10%. Finally, it is crushed to 5mm by a pulverizer to obtain pre-treated bamboo shavings. S2: High-temperature directional carbonization The pretreated bamboo chips are fed into a continuous vertical carbonization furnace (5m³ volume, made of high-temperature resistant stainless steel), and nitrogen gas (flow rate 0.8m³ / h) is introduced to isolate oxygen for protection. The temperature is increased according to the following procedure: First stage: Increase the temperature to 300℃ at a rate of 5℃ / min and hold for 1.5 hours; Second stage: Continue to heat to 600℃ at a rate of 8℃ / min, and hold for 2 hours; Third stage: Continue heating to 1000℃ at a rate of 12℃ / min, and hold for 2 hours; Cooling stage: After carbonization, the bamboo charcoal is slowly cooled to 120°C under nitrogen protection (to prevent oxidation) to obtain coarse bamboo charcoal (containing a small amount of non-volatile tar and wood vinegar residue). S3: Flue Gas Collection and Separation The flue gas produced during the carbonization process (mainly composed of wood tar vapor, wood vinegar vapor, ...) Combustible gases and water vapor are introduced into a multi-stage condensation system through high-temperature resistant pipes (≥1000℃ tolerance): Preheating section: Removes large particles of dust (such as incompletely crushed bamboo shavings) from the flue gas at a heating temperature of 200℃. First-stage condenser (60℃): Separates crude tar (density 1.2g / cm³, containing anthracene and naphthalene aromatic compounds); Secondary condenser (25℃): Condensation yields crude wood vinegar (pH 4.0, main components are acetic acid, propionic acid and phenols); Non-condensable gas treatment: Residual non-condensable gases (mainly...) (And a small amount of nitrogen) is removed by spraying with a 5-7% sodium hydroxide solution in a desulfurization tower. After purification, it is temporarily stored in a gas storage tank; S4: Bamboo Charcoal Post-treatment The coarse bamboo charcoal is crushed to 3mm and placed in an activation furnace. It is activated for 1.5 hours in a steam atmosphere at 850℃ (flow rate 0.5kg / h) (the steam reacts with the carbon on the surface of the bamboo charcoal to generate micropores, increasing the specific surface area). Then it is cooled to room temperature. It is washed with deionized water until the pH reaches 7.0 (to remove residual acid and alkali impurities). Finally, it is dried at 105℃ for 3 hours to obtain the finished bamboo charcoal. Optional applications: The finished bamboo charcoal is mixed with bentonite at a mass ratio of 9:1 and pressed into columnar charcoal with a diameter of 5cm and a length of 10cm under a pressure of 20MPa (suitable for sewage treatment or air purification). S5: Deep utilization of flue gas Wood vinegar: After the crude wood vinegar is allowed to stand and separate into layers (to remove impurities at the bottom), it is filtered through a 0.45μm filter membrane and then vacuum distilled at 60℃ and -0.08MPa. The fraction at 105℃ is collected to obtain refined wood vinegar. Wood tar: Crude tar is distilled under reduced pressure at -0.09 MPa (250℃ range) to separate high-value-added aromatic compounds such as anthracene and naphthalene; Combustible gas: The purified gas in the gas storage tank is pressurized to 0.3MPa and reused as the carrier gas for the carbonization furnace (replacing part of the nitrogen), reducing external energy consumption.

[0020] Example 3 A high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips includes the following steps: S1: Bamboo Shavings Pretreatment After removing impurities from the bamboo shavings through a 19-mesh vibrating screen, the raw material is rinsed 3.5 times with running water to remove surface dust. Then it is placed in a 62℃ hot air drying oven to dry for 4 hours until the moisture content is 9%. Finally, it is crushed to 4mm by a pulverizer to obtain pre-treated bamboo shavings. S2: High-temperature directional carbonization The pretreated bamboo chips are fed into a continuous vertical carbonization furnace (5m³ volume, made of high-temperature resistant stainless steel), and nitrogen gas (flow rate 0.8m³ / h) is introduced to isolate oxygen for protection. The temperature is increased according to the following procedure: First stage: Increase the temperature to 260℃ at a rate of 5℃ / min and hold for 1.5 hours; Second stage: Continue to heat to 500℃ at a rate of 8℃ / min, and hold for 2 hours; Third stage: Continue to heat to 900℃ at a rate of 12℃ / min, and hold for 2 hours; Cooling stage: After carbonization, the bamboo charcoal is slowly cooled to 117°C under nitrogen protection (to prevent oxidation) to obtain coarse bamboo charcoal (containing a small amount of non-volatile tar and wood vinegar residue). S3: Flue Gas Collection and Separation The flue gas produced during the carbonization process (mainly composed of wood tar vapor, wood vinegar vapor, ...) Combustible gases and water vapor are introduced into a multi-stage condensation system through high-temperature resistant pipes (≥1000℃ tolerance): Preheating section: Removes large particles of dust (such as incompletely crushed bamboo shavings) from the flue gas by heating at 197℃. First-stage condenser (60℃): Separates crude tar (density 1.1g / cm³, containing anthracene and naphthalene aromatic compounds); Secondary condenser (25℃): Condensation yields crude wood vinegar (pH 3.6, main components are acetic acid, propionic acid and phenols); Non-condensable gas treatment: Residual non-condensable gases (mainly...) (And a small amount of nitrogen) is removed by spraying in a desulfurization tower (using a 6% sodium hydroxide solution). After purification, it is temporarily stored in a gas storage tank; S4: Bamboo Charcoal Post-treatment The coarse bamboo charcoal is crushed to 2mm and placed in an activation furnace. It is activated for 1.2 hours in a steam atmosphere at 840℃ (flow rate 0.5kg / h) (the steam reacts with the carbon on the surface of the bamboo charcoal to generate micropores, increasing the specific surface area). Then it is cooled to room temperature; washed with deionized water until pH 6.8 (to remove residual acid and alkali impurities), and finally dried at 103℃ for 2.5 hours to obtain the finished bamboo charcoal. Optional applications: The finished bamboo charcoal is mixed with bentonite at a mass ratio of 9:1 and pressed into columnar charcoal with a diameter of 5cm and a length of 10cm under a pressure of 20MPa (suitable for sewage treatment or air purification). S5: Deep utilization of flue gas Wood vinegar: After the crude wood vinegar is allowed to stand and separate into layers (to remove impurities at the bottom), it is filtered through a 0.45μm filter membrane and then vacuum distilled at 60℃ and -0.08MPa. The fraction at 103℃ is collected to obtain refined wood vinegar. Wood tar: Crude tar is distilled under reduced pressure at -0.09 MPa (240℃ range) to separate high-value-added aromatic compounds such as anthracene and naphthalene; Combustible gas: The purified gas in the gas storage tank is pressurized to 0.28MPa and reused as the carrier gas for the carbonization furnace (replacing part of the nitrogen), reducing external energy consumption.

[0021] Example 4 A high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips includes the following steps: S1: Bamboo Shavings Pretreatment After removing impurities by passing the bamboo shavings through an 18-mesh vibrating screen, the raw material is rinsed three times with running water to remove surface dust. Then, it is placed in a 60℃ hot air drying oven to dry for 3 hours until the moisture content is 8%. Finally, it is crushed to 3mm by a pulverizer to obtain pre-treated bamboo shavings. S2: High-temperature directional carbonization The pretreated bamboo chips are fed into a continuous vertical carbonization furnace (5m³ volume, made of high-temperature resistant stainless steel), and nitrogen gas (flow rate 0.8m³ / h) is introduced to isolate oxygen for protection. The temperature is increased according to the following procedure: First stage: Heat to 200℃ at a rate of 5℃ / min and hold for 1.5 hours; Second stage: Continue to heat to 400℃ at a rate of 8℃ / min, and hold for 2 hours; Third stage: Continue to heat to 800℃ at a rate of 12℃ / min, and hold for 2 hours; Cooling stage: After carbonization, the bamboo charcoal is slowly cooled to 115°C under nitrogen protection (to prevent oxidation) to obtain coarse bamboo charcoal (containing a small amount of non-volatile tar and wood vinegar residue). S3: Flue Gas Collection and Separation The flue gas produced during the carbonization process (mainly composed of wood tar vapor, wood vinegar vapor, ...) Combustible gases and water vapor are introduced into a multi-stage condensation system through high-temperature resistant pipes (≥1000℃ tolerance): Preheating section: Removes large particles of dust (such as incompletely crushed bamboo shavings) from the flue gas at a heating temperature of 200℃. First-stage condenser (60℃): Separates crude tar (density 1.2g / cm³, containing anthracene and naphthalene aromatic compounds); Secondary condenser (25℃): Condensation yields crude wood vinegar (pH 4.0, main components are acetic acid, propionic acid and phenols); Non-condensable gas treatment: Residual non-condensable gases (mainly...) (And a small amount of nitrogen) is removed by spraying with a 5-7% sodium hydroxide solution in a desulfurization tower. After purification, it is temporarily stored in a gas storage tank; S4: Bamboo Charcoal Post-treatment The coarse bamboo charcoal is crushed to 2mm and placed in an activation furnace. It is activated for 1.2 hours in a steam atmosphere at 840℃ (flow rate 0.5kg / h) (the steam reacts with the carbon on the surface of the bamboo charcoal to generate micropores, increasing the specific surface area). Then it is cooled to room temperature; washed with deionized water until pH 6.8 (to remove residual acid and alkali impurities), and finally dried at 103℃ for 2.5 hours to obtain the finished bamboo charcoal. Optional applications: The finished bamboo charcoal is mixed with bentonite at a mass ratio of 9:1 and pressed into columnar charcoal with a diameter of 5cm and a length of 10cm under a pressure of 20MPa (suitable for sewage treatment or air purification). S5: Deep utilization of flue gas Wood vinegar: After the crude wood vinegar is allowed to stand and separate into layers (to remove impurities at the bottom), it is filtered through a 0.45μm filter membrane and then vacuum distilled at 60℃ and -0.08MPa. The fraction at 103℃ is collected to obtain refined wood vinegar. Wood tar: Crude tar is distilled under reduced pressure at -0.09 MPa (240℃ range) to separate high-value-added aromatic compounds such as anthracene and naphthalene; Combustible gas: The purified gas in the gas storage tank is pressurized to 0.28MPa and reused as the carrier gas for the carbonization furnace (replacing part of the nitrogen), reducing external energy consumption.

[0022] Performance testing Conducted in accordance with GB 16297-1996 "Integrated Emission Standard for Air Pollutants" Emissions, particulate matter testing.

[0023] Table 1: Indicator Test.

[0024]

[0025] As shown in Table 1, the bamboo charcoal of the present invention has a good adsorption effect and the process is green and low-carbon.

[0026] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0027] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

[0028] Those skilled in the art should understand that the above descriptions are merely several specific embodiments of the present invention, and not all embodiments.

Claims

1. A high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips, characterized in that, Includes the following steps: S1: Bamboo Shavings Pretreatment After removing impurities from the bamboo shavings through an 18-20 mesh vibrating screen, the raw bamboo shavings are rinsed 3-4 times with running water to remove surface dust. Then, they are placed in a 60-65℃ hot air drying oven to dry for 3-4 hours until the moisture content is 8-10%. Finally, they are crushed by a pulverizer to obtain pre-treated bamboo shavings. S2: High-temperature directional carbonization The pretreated bamboo chips are fed into a continuous vertical carbonization furnace (5m³ volume, made of high-temperature resistant stainless steel), and nitrogen gas (flow rate 0.8m³ / h) is introduced to isolate oxygen for protection. The temperature is increased according to the following procedure: First stage: Heat at a rate of 5℃ / min and hold for 1.5 hours; Second stage: Continue to heat to 400-600℃ at a rate of 8℃ / min, and hold for 2 hours; Third stage: Continue to heat to 800-1000℃ at a rate of 12℃ / min, and hold for 2 hours; Cooling stage: After carbonization, the bamboo charcoal is slowly cooled under nitrogen protection (to prevent oxidation) to obtain coarse bamboo charcoal (containing a small amount of non-volatile tar and wood vinegar residue). S3: Flue Gas Collection and Separation The flue gas produced during the carbonization process (mainly composed of wood tar vapor, wood vinegar vapor, ...) Combustible gases and water vapor are introduced into a multi-stage condensation system through high-temperature resistant pipes (≥1000℃ tolerance): Preheating section: Removes large particles of dust (such as incompletely crushed bamboo shavings) from the flue gas under heating conditions. First-stage condenser (60℃): Separates crude tar (density 1.0~1.2g / cm³, containing anthracene and naphthalene aromatic compounds); Secondary condenser (25℃): Condensation yields crude wood vinegar (pH 3.5~4.0, main components are acetic acid, propionic acid and phenols); Non-condensable gas treatment: Residual non-condensable gases (mainly...) (And a small amount of nitrogen) is removed by spraying sodium hydroxide solution in a desulfurization tower. After purification, it is temporarily stored in a gas storage tank; S4: Bamboo Charcoal Post-treatment The coarse bamboo charcoal is crushed to 1-3mm and placed in an activation furnace. It is activated in a steam atmosphere (flow rate 0.5kg / h) at 830-850℃ (the steam reacts with the carbon on the surface of the bamboo charcoal to generate micropores, increasing the specific surface area). Then it is cooled to room temperature. It is washed with deionized water until the pH reaches 6.5-7.0 (to remove residual acid and alkali impurities). Finally, it is dried at 102-105℃ for 2-3 hours to obtain the finished bamboo charcoal. S5: Deep utilization of flue gas Wood vinegar: After the crude wood vinegar is allowed to stand and separate into layers, it is filtered through a 0.45μm filter membrane and then vacuum distilled at 60℃ and -0.08MPa. The fraction at 102-105℃ is collected to obtain refined wood vinegar. Wood tar: Crude tar is distilled under reduced pressure at -0.09 MPa (220-250℃ range) to separate high-value-added aromatic compounds such as anthracene and naphthalene; Combustible gas: The purified gas in the gas storage tank is pressurized and reused as the carrier gas in the carbonization furnace (replacing part of the nitrogen), reducing external energy consumption.

2. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The particle size of the powder crushed in S1 is 3-5 mm.

3. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The first stage of heating in S2 is at a temperature of 200-300℃.

4. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The cooling temperature in the S2 stage is reduced to 115-120℃.

5. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The heating temperature in S3 is 195-200℃.

6. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The sodium hydroxide solution in S3 has a mass fraction of 5-7%.

7. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The activation time in S4 is 1-1.5 hours.

8. The high-temperature bamboo charcoal preparation and flue gas resource utilization process for the complete utilization of bamboo chips according to claim 1, characterized in that, The pressurization pressure of the combustible gas in S5 is 0.26-0.3 MPa.

Images