Utilization system for tail gas in bamboo activated carbon production and bamboo activated carbon production system

Abstract

The utility model discloses a bamboo activated carbon production tail gas utilization system and a bamboo activated carbon production system. The utilization system comprises a condensing device for condensing production tail gas to obtain non-condensable gas; the dust removal equipment is used for carrying out dust removal treatment on the non-condensable gas to obtain low-dust gas; an air inlet of the dust removal equipment is connected with an air outlet of the condensing equipment; the adsorption equipment is used for carrying out adsorption treatment on the low-dust gas to obtain adsorbed tail gas; a gas inlet of the adsorption equipment is connected with a gas outlet of the dust removal equipment; the deacidification equipment is used for carrying out deacidification treatment on the adsorbed tail gas to obtain reaction gas; a gas inlet of the deacidification equipment is connected with a gas outlet of the adsorption equipment; the reaction equipment is internally provided with a catalyst filler structure, and the reaction gas is subjected to a catalytic reaction in the reaction equipment through a catalyst to obtain H2-containing synthesis gas; and a gas inlet of the reaction equipment is connected with a gas outlet of the deacidification equipment.

Description

Technical Field

[0001] This utility model relates to the technical field of bamboo activated carbon production, and more specifically, to a system for utilizing exhaust gas from bamboo activated carbon production and a bamboo activated carbon production system. Background Technology

[0002] Biomass energy is the fourth largest energy source after coal, oil, and natural gas. Biomass energy uses biomass as its carrier, typically derived from firewood, straw, livestock manure, and municipal waste. Modern technologies usually convert this biomass into solid, liquid, or gaseous fuels for utilization. Bamboo energy is an important form of biomass energy, possessing advantages such as low pollution, wide distribution, abundant reserves, and renewability. my country has the world's richest bamboo resources, providing favorable conditions and an ideal environment for developing bamboo energy.

[0003] Currently, one important use of bamboo resources in my country is for the production of bamboo-based activated carbon. The production process mainly includes carbonization and activation. The carbonization process can be done once or twice. Secondary carbonization usually refers to grinding, kneading, and granulating the primary carbonized material into special shapes such as columnar, honeycomb, or spherical forms, and then performing a secondary carbonization to remove the binder used in granulation. In addition to the large amount of exhaust gas generated during the activation process, both primary and secondary carbonization processes also produce a significant amount of exhaust gas, and the composition of the exhaust gas produced by the two carbonization processes is significantly different.

[0004] Besides protective gas and water vapor, the exhaust gas produced by primary carbonization mainly consists of CO, CO2, H2, volatile organic compounds (such as alkanes, alkenes, aldehydes, etc.), organic vapors (such as terpenes, tannins, methanol, etc.), and acidic gases (such as formic acid, phenol, acetic acid, H2S, SO2, NH3, nitrogen oxides, etc.) produced by the pyrolysis of biomass components (such as lignin and hemicellulose).

[0005] The exhaust gases produced by secondary carbonization vary considerably depending on the type of binder. For example, the main components of exhaust gases from traditional secondary carbonization using asphalt or coal tar as binders are protective gases, water vapor, CO, CO2, volatile organic compounds (such as benzene, toluene, xylene, methylphenol, ethylphenol, etc.), and acidic gases (such as phenol, formic acid, acetic acid, aldehydes, nitrogen oxides, etc.), which are highly toxic. When using polymeric binders (such as starch, molasses, carboxymethyl cellulose, lignin, gelatin, chitosan, etc.), the content of volatile organic compounds and acidic gases in the secondary carbonization exhaust gases is significantly reduced, and the main components are protective gases, water vapor, CO, and CO2.

[0006] During the activation process, the activator reacts with carbon, causing erosion of the channels and generating a large number of micropores. The main components of the activated waste gas, in addition to protective gas and activator (such as water vapor, CO2, O2), also contain H2, CO, small amounts of volatile organic compounds (such as CH4, C2H4, propylene), and acidic gases (such as phenol).

[0007] If the exhaust gases generated during carbonization and activation can be converted into clean energy, the utilization rate of bamboo resources can be significantly improved. Chinese invention patent CN116332128A discloses a system and method for preparing methanol and high-quality activated carbon from biomass. This method directly uses the exhaust gases generated during activation in a water-gas conversion reaction, followed by a CO hydrogenation reaction to ultimately obtain methanol. However, on the one hand, a large amount of exhaust gas generated during carbonization is not recovered and utilized; on the other hand, directly using the activation exhaust gases for synthesis reactions easily leads to catalyst poisoning and results in low methanol purity. Utility Model Content

[0008] The technical problem to be solved by this utility model is to provide a simple and efficient method and system for utilizing bamboo activated carbon production exhaust gas, which can convert the exhaust gas of bamboo activated carbon production into clean energy, as well as a method and system for producing bamboo activated carbon.

[0009] To achieve the above objectives, according to the first aspect of this utility model, a method and system for utilizing the exhaust gas from bamboo activated carbon production are provided, the technical solution of which is as follows:

[0010] A method for utilizing the tail gas from bamboo activated carbon production includes carbonization tail gas from the carbonization process of bamboo raw materials and activation tail gas from the subsequent activation treatment. The activating agent used in the activation treatment is water vapor. The utilization method includes the following steps: purifying the tail gas to remove water vapor, organic vapors, volatile organic compounds, acidic gases, and particulate impurities. The purified tail gas should have a water vapor volume fraction of 15-25%, a COD content ≤5 ppm, a volatile organic compound content ≤3 ppm, an acidic gas content ≤2 ppm, and a particulate matter content ≤20 mg / Nm³. 3 The production exhaust gas is passed into a reaction device containing a Cu-Zr catalyst, where a catalytic reaction is carried out at 240–300°C to generate syngas containing H2.

[0011] As a further improvement to the above-mentioned method for utilizing the exhaust gas from bamboo activated carbon production: the purification treatment includes sequentially performing condensation treatment, dust removal treatment, adsorption treatment and deacidification treatment on the exhaust gas; the deacidification treatment adopts wet deacidification.

[0012] As a further improvement to the above-mentioned method for utilizing the exhaust gas from bamboo activated carbon production, it also includes purifying the condensate obtained from the condensation treatment to obtain biomass oil.

[0013] As a further improvement to the above-mentioned method for utilizing the tail gas from bamboo activated carbon production, it further includes removing CO2 from the tail gas using a CO2 selective separation membrane before the catalytic reaction; and / or, it further includes removing CO2 from the syngas using a CO2 selective separation membrane after the catalytic reaction.

[0014] As a further improvement to the above-mentioned method for utilizing the tail gas from bamboo activated carbon production, a method for preparing Cu-Zr catalyst includes the following steps:

[0015] An aqueous solution containing urea and soluble zirconium salt is prepared, the aqueous solution is subjected to hydrothermal treatment, and the resulting first solid is collected, washed, and dried.

[0016] The first solid was calcined to obtain a zirconium precursor.

[0017] Zirconium precursor and copper salt were ground and mixed, then dispersed in deionized water to form a dispersion. Alkali solution was added to the dispersion under water bath conditions, and the resulting second solid was collected, washed and dried.

[0018] The second solid was calcined to obtain the Cu-Zr catalyst.

[0019] As a further improvement to the above-mentioned method for utilizing the exhaust gas from bamboo activated carbon production: the soluble zirconium salt is zirconium nitrate, and the molar ratio of urea to zirconium ions in the aqueous solution is 1.8 to 2.2; the hydrothermal reaction temperature is 140 to 160°C, and the hydrothermal reaction time is 18 to 30 hours.

[0020] As a further improvement to the above-mentioned method for utilizing the exhaust gas from bamboo activated carbon production: the calcination temperature for calcining the first solid is 230–270°C, and the calcination time is 3–5 hours.

[0021] As a further improvement to the above-mentioned method for utilizing the exhaust gas from bamboo activated carbon production: the copper salt is copper nitrate, the molar ratio of copper ions to zirconium ions is 0.1 to 0.15; the water bath temperature is 50 to 70°C, sodium hydroxide is used as the alkaline solution, and the dispersion is adjusted to pH 9 with sodium hydroxide after stirring for 1 to 3 hours under water bath conditions.

[0022] As a further improvement to the above-mentioned method for utilizing the exhaust gas from bamboo activated carbon production: the calcination temperature for calcining the second solid is 350–450°C, and the calcination time is 3–5 hours.

[0023] A system for utilizing exhaust gas from bamboo activated carbon production includes carbonization exhaust gas from a carbonization furnace that carbonizes bamboo raw materials and activation exhaust gas from a cremation furnace that activates the carbonized material. The activating agent used in the activation treatment is water vapor. The system comprises: a condensation device for condensing the exhaust gas to obtain non-condensable gas; a dust removal device for removing dust from the non-condensable gas to obtain low-dust gas; the inlet of the dust removal device is connected to the outlet of the condensation device; an adsorption device for adsorbing the low-dust gas to obtain adsorbed exhaust gas; the inlet of the adsorption device is connected to the outlet of the dust removal device; a deacidification device for deacidifying the adsorbed exhaust gas to obtain reactive gas; the inlet of the deacidification device is connected to the outlet of the adsorption device; and a reaction device containing a catalyst packing structure, where the reactive gas undergoes a catalytic reaction to obtain syngas containing H2; the inlet of the reaction device is connected to the outlet of the deacidification device.

[0024] As a further improvement to the above-mentioned bamboo activated carbon production tail gas utilization system: the dust removal equipment is a filter using a porous metal filter element.

[0025] As a further improvement to the above-mentioned bamboo activated carbon production tail gas utilization system, the deacidification equipment is a spray tower.

[0026] As a further improvement to the above-mentioned bamboo activated carbon production tail gas utilization system: the adsorption equipment is equipped with an activated carbon packing structure.

[0027] As a further improvement to the above-mentioned bamboo activated carbon production tail gas utilization system, it also includes a first separation device for removing CO2 from the reaction gas; and / or, it also includes a second separation device for removing CO2 from the synthesis gas.

[0028] As a further improvement to the above-mentioned bamboo activated carbon production tail gas utilization system: both the first separation device and the second separation device are membrane separation devices equipped with CO2 selective separation membranes, wherein the CO2 selective separation membrane is any one of polyetherimide membrane, polyamide membrane, and carbon membrane.

[0029] To achieve the above objectives, according to a second aspect of this utility model, a method and system for producing bamboo activated carbon using the bamboo activated carbon production tail gas utilization method and system described in the first aspect are provided. The technical solution is as follows:

[0030] A method for producing bamboo activated carbon includes carbonization and activation treatment of bamboo raw materials, and also includes utilizing the production tail gas using the above-mentioned method for utilizing bamboo activated carbon production tail gas, wherein the production tail gas includes carbonization tail gas generated from carbonization treatment of bamboo raw materials and activation tail gas generated from activation treatment after carbonization.

[0031] The carbonization process includes the following steps:

[0032] The dried bamboo raw material is placed in a carbonization furnace, and the furnace temperature is raised from room temperature to 130-280℃ under an inert atmosphere and held for 0.5-1.5 hours.

[0033] Continue heating to 300–400℃ and hold for 0.5–1.5 hours;

[0034] Continue heating to 500-600℃, hold at that temperature for 0.5-1.5 hours, then cool with the furnace to obtain the carbonized material;

[0035] The activation process is as follows: the carbonized material is placed in an activation furnace, and under an inert atmosphere, water vapor is used as the activating agent. After being kept at 800-1100℃ for 2-4 hours, the material is cooled with the furnace to obtain bamboo activated carbon.

[0036] The bamboo activated carbon production system includes a carbonization furnace for carbonizing bamboo raw materials and an activation furnace for activating bamboo raw materials after carbonization. The activating agent used in the activation process is water vapor. The system also includes a system for utilizing the exhaust gas from the bamboo activated carbon production process. The exhaust gas includes carbonization exhaust gas generated by the carbonization furnace and activation exhaust gas generated by the activation furnace.

[0037] This utility model has the following advantages:

[0038] (1) Effectively utilize the tail gas generated during the carbonization process (either single or double carbonization) and activation process of bamboo raw materials. Through the catalytic reaction of CO and water vapor, the tail gas is converted into syngas including H2 (reaction equation: CO + H2O → CO2 + H2). This not only reduces the pollution of the environment caused by tail gas emissions, but also H2 is a clean energy source. On the one hand, it can be recycled and reused as an energy source, reducing the external energy consumption of bamboo activated carbon production and enhancing the overall competitiveness of bamboo activated carbon production. On the other hand, it can be used for industrial applications (such as hydrogen-powered vehicles, oil refining, etc.) and can be sold to increase the economic benefits of enterprises.

[0039] (2) Removing excess water vapor, organic vapor, volatile organic compounds, acidic gases, and particulate impurities from the exhaust gas before the catalytic reaction helps improve catalyst activity and catalytic reaction efficiency, reduces catalyst poisoning and equipment clogging and wear, and results in less impurities in the obtained syngas, which helps simplify the subsequent H2 purification process. Furthermore, the condensate obtained after carbonization exhaust gas condensation contains a significant amount of organic matter, which can be condensed into bio-oil with high calorific value, further generating revenue for the enterprise.

[0040] The embodiments of the invention provided in this specification will be further described below with reference to the accompanying drawings and specific embodiments. Additional aspects and advantages of the embodiments of the invention provided in this specification will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the embodiments of the invention provided in this specification. Attached Figure Description

[0041] The accompanying drawings, which form part of the embodiments of the invention provided in this specification, are used to aid in understanding the embodiments of the invention provided in this specification. The content provided in the drawings and the related descriptions in the embodiments of the invention provided in this specification can be used to explain the embodiments of the invention provided in this specification, but do not constitute an undue limitation on the embodiments of the invention provided in this specification. In the drawings:

[0042] Figure 1 This is a schematic diagram of the first embodiment of a bamboo activated carbon production system and a bamboo activated carbon production tail gas utilization system.

[0043] Figure 2 This is a schematic diagram of the second embodiment of the bamboo activated carbon production system and the bamboo activated carbon production tail gas utilization system.

[0044] Figure 3 The image shows the XRD pattern of the Cu-Zr catalyst.

[0045] The relevant markings in the above figures are:

[0046] 210 - Gas collecting tank, 220 - Condensation equipment, 230 - Dust removal equipment, 240 - Adsorption equipment, 250 - Deacidification equipment, 260 - Reaction equipment, 270 - First separation equipment, 280 - Second separation equipment. Detailed Implementation

[0047] The embodiments of the invention provided in this specification will now be clearly and completely described in conjunction with the accompanying drawings. Those skilled in the art will be able to implement the embodiments of the invention provided in this specification based on these descriptions. Before describing the embodiments of the invention provided in this specification in conjunction with the accompanying drawings, it should be particularly noted that:

[0048] The technical solutions and features provided in the embodiments of the invention provided in this specification, including the following description, can be combined with each other without conflict.

[0049] Furthermore, the embodiments of the inventions provided in this specification mentioned below are generally only a portion of the embodiments of the inventions provided in this specification, and not all of them. Therefore, all other embodiments obtained by those skilled in the art based on the embodiments of the inventions provided in this specification without creative effort should fall within the scope of protection of the embodiments of the inventions provided in this specification.

[0050] Regarding the terminology and units in the embodiments of the invention provided in this specification: The terms "comprising," "including," "having," and any variations thereof in the description, claims, and related parts of the embodiments of the invention provided in this specification are intended to cover non-exclusive inclusion. Furthermore, other relevant terms and units in the embodiments of the invention provided in this specification can be reasonably interpreted based on the relevant content of the embodiments of the invention provided in this specification.

[0051] The first embodiment of the bamboo activated carbon production method of this utility model includes the following steps:

[0052] Drying process: Place fresh bamboo raw materials in an oven and dry at 100℃ for 48 hours.

[0053] One-time carbonization process: Place the dried bamboo raw material into a carbonization furnace, and under an inert atmosphere, raise the furnace temperature from room temperature to 200°C and hold for 1 hour; continue to raise the temperature to 350°C and hold for 1 hour; continue to raise the temperature to 550°C and hold for 1 hour, then cool with the furnace to obtain the carbonized material.

[0054] Activation treatment: The carbonized material is placed in an activation furnace. Under an inert atmosphere, water vapor is used as the activating agent. The volume of liquid water introduced per 100g of green body per hour is 40mL. After being kept at 1000℃ for 3 hours, the material is cooled with the furnace to obtain bamboo activated carbon.

[0055] Compared with the first embodiment, the second embodiment of the bamboo activated carbon production method of this utility model differs in that it further includes a secondary carbonization process: the primary carbonized material is ground to a particle size of 325 mesh, and then granulated into a green body in a kneader using molasses as a binder and water as an additive, according to a mass ratio of molasses to primary carbonized material of 0.5 and a ratio of 30 mL of additive per 100 g of primary carbonized material. The green body is placed in a carbonization furnace, and under an inert atmosphere, the furnace temperature is raised from room temperature to 550°C and held for 1 hour. After cooling in the furnace, the secondary carbonized material is obtained. Then, the secondary carbonized material is activated to obtain bamboo activated carbon.

[0056] The method for utilizing the tail gas from the production of bamboo activated carbon of this utility model is used to utilize the tail gas generated by the bamboo activated carbon production method described in the first or second embodiment above. That is, the tail gas includes carbonized tail gas generated by primary carbonization treatment or primary carbonization treatment and secondary carbonization treatment, and activated tail gas generated by activation treatment after carbonization.

[0057] The first embodiment of the method for utilizing the exhaust gas from bamboo activated carbon production includes the following steps:

[0058] The production exhaust gas is purified to remove water vapor, organic vapors, volatile organic compounds (VOCs), acidic gases, and particulate impurities. The purification process includes sequential condensation, dust removal, adsorption, and deacidification. Condensation removes water vapor, VOCs, and low-boiling-point acidic gases. Filtration is preferred for dust removal. Adsorption adsorbs VOCs, preferably using activated carbon as the adsorbent. Deacidification removes residual acidic gases, preferably using a wet scrubbing tower with a circulating liquid absorbent. The purified exhaust gas has a water vapor volume fraction of 15-25%, COD ≤5 ppm, VOCs ≤3 ppm, acidic gases ≤2 ppm, and particulate matter ≤20 mg / Nm³. 3 .

[0059] The production exhaust gas is fed into a reaction device containing a Cu-Zr catalyst, where a catalytic reaction is carried out at 240–300°C to generate syngas containing H2.

[0060] A second embodiment of the method for utilizing the tail gas from bamboo activated carbon production is as follows: Based on the first embodiment, it further includes removing CO2 from the tail gas using a CO2 selective separation membrane before the catalytic reaction and removing CO2 from the syngas using a CO2 selective separation membrane after the catalytic reaction.

[0061] Figure 1This is a schematic diagram of the first embodiment of a bamboo activated carbon production system and a system for utilizing the exhaust gas from bamboo activated carbon production. Figure 1 As shown, the bamboo activated carbon production system includes a carbonization furnace (one or two) for carbonizing bamboo raw materials, an activation furnace for activating the carbonized raw materials, and a system for utilizing the production exhaust gas. The production exhaust gas includes carbonization exhaust gas discharged from one or two carbonization furnaces and activation exhaust gas discharged from the activation furnace.

[0062] The first embodiment of the system for utilizing exhaust gas from bamboo activated carbon production includes a gas collection tank 210, a condensation device 220, a dust removal device 230, an adsorption device 240, a deacidification device 250, and a reaction device 260.

[0063] The gas collecting tank 210 is used to collect and output production exhaust gas, and its outlet is connected to the inlet of the condensing device 220. The condensing device 220 condenses the production exhaust gas to obtain non-condensable gas. The dust removal device 230 removes dust from the non-condensable gas to obtain low-dust gas. The inlet of the dust removal device 230 is connected to the outlet of the condensing device 220, and the dust removal device 230 is a filter using a porous metal filter element. The adsorption device 240 adsorbs the low-dust gas to obtain adsorbed exhaust gas. The inlet of the adsorption device 240 is connected to the outlet of the dust removal device 230, and the adsorption device 240 is equipped with an activated carbon packing structure. The deacidification device 250 deacidifies the adsorption tail gas to obtain a reaction gas. The inlet of the deacidification device 250 is connected to the outlet of the adsorption device 240. The deacidification device 250 is a wet deacidification spray tower, which deacidifies by spraying liquid absorbent and can increase the humidity of the reaction gas, making it more suitable for the H2 synthesis reaction. The reaction device 260 is equipped with a catalyst packing structure. The reaction gas undergoes a catalytic reaction in the reaction device 260 to obtain a synthesis gas containing H2. The inlet of the reaction device 260 is connected to the outlet of the deacidification device 250.

[0064] Figure 2 This is a schematic diagram of a second embodiment of a bamboo activated carbon production system and a system for utilizing the exhaust gas from bamboo activated carbon production. Figure 2As shown, compared to the first embodiment, the utilization system of the second embodiment further includes a first separation device 270 for removing CO2 from the reaction gas and a second separation device 280 for removing CO2 from the synthesis gas. Both the first separation device 270 and the second separation device 280 are membrane separation devices equipped with CO2 selective separation membranes, which are any one of polyetherimide membranes, polyamide membranes, and carbon membranes. An appropriate amount of CO2 helps maintain catalyst activity, but too much will inhibit the H2 synthesis reaction. Therefore, removing excess CO2 through the first separation device 270, reducing the CO2 volume fraction to 2-5%, can promote the reaction towards H2 generation; removing CO2 from the synthesis gas through the second separation device 280 can improve the purity of H2.

[0065] The preparation method of the Cu-Zr catalyst used in the above reaction equipment includes the following steps:

[0066] Zirconium nitrate and urea were dissolved in 150 mL of deionized water to form an aqueous solution with a molar ratio of urea to zirconium ions of 2 and a zirconium ion concentration of 0.2 mol / L. The aqueous solution was subjected to hydrothermal treatment at a temperature of 150 °C for 24 hours. The resulting first solid was collected, washed, and dried.

[0067] The first solid was calcined at 250°C for 4 hours to obtain a zirconium precursor.

[0068] Zirconium precursor and copper nitrate were ground and mixed, with a molar ratio of copper ions to zirconium ions (calculated according to zirconium nitrate) of 0.12. The ground mixture was then dispersed in 200 mL of deionized water to form a dispersion. The mixture was stirred for 2 hours in a water bath at 60 °C. Sodium hydroxide was then slowly added dropwise to the dispersion until the pH of the dispersion was 9. The resulting second solid was collected, washed, and dried.

[0069] The second solid was calcined at 400℃ for 4 hours to obtain the Cu-Zr catalyst.

[0070] Figure 3 The image shows the XRD pattern of the Cu-Zr catalyst. Figure 3 As shown, the Cu-Zr catalyst exhibits good crystal structure, and its XRD pattern shows CuO. x The characteristic peaks of Cu and ZrO2 indicate that Cu was not embedded in the zirconium precursor (ZrO2) during the preparation process, but was uniformly attached to the ZrO2 surface as CuOx. Through the interaction between the two, a better catalytic effect was produced.

[0071] The specific surface area of ​​the zirconium precursor (ZrO2) was determined to be 37.35 m² / s² using N₂ adsorption-desorption experiments and the BET (Brunauer-Emmett-Teller) method. 2 / g, total pore volume is 0.22cm³ 3 / g, with an average pore size of 23.6nm, and a specific surface area of ​​56.48m² for the Cu-Zr catalyst. 2 / g, total pore volume is 0.30cm³ 3 / g, with an average pore size of 21.8nm, indicating that the supported CuO... x Subsequently, the specific surface area of ​​the Cu-Zr catalyst increased significantly, which played a decisive role in the adsorption and activation of the gas.

[0072] A mixture of gas with volume fractions of 15% CO, 40% H2, 35% N2, and 10% CO2 was mixed with water vapor and catalyzed using a Cu-Zr catalyst at 180–300 °C. The results showed that the CO conversion rate increased sharply with increasing catalytic temperature, and then gradually leveled off. The CO conversion rates at 180 °C, 210 °C, 240 °C, 270 °C, and 300 °C were 62%, 79%, 85%, 86%, and 87%, respectively.

[0073] The Cu-Zr catalyst was used to catalyze the reaction gas (in one embodiment, the composition was 21.54% CO, 3.14% CO2, 23.55% H2, 22.35% water vapor, with the balance being N2) after treatment by the first separation unit 270. The reaction temperature was 270°C, the reaction pressure was 5 MPa, and the space velocity was 5000 h⁻¹. -1 The CO conversion rate was 81%.

[0074] It is evident that the preparation method of the Cu-Zr catalyst is simple, and the resulting Cu-Zr catalyst exhibits high catalytic activity and stability. It can promote the reaction of CO and water vapor at relatively low temperatures, contributing to improved stability in the syngas production process and reduced catalyst replacement frequency, thereby saving long-term operating costs. Achieving effective conversion of tail gas from bamboo activated carbon production through catalytic reaction technology is an innovative green chemical process that aligns with the global trend of promoting green production and reducing carbon emissions, and has a significant promotional effect on the development and application of bamboo resources.

[0075] The condensate obtained after condensing the carbonization tail gas contains a large amount of organic matter, which can be condensed into bio-oil with high calorific value. To further recover the valuable resources from the production tail gas, the method for utilizing bamboo activated carbon production tail gas of this invention further utilizes the condensate recovered from the condensation equipment. Based on the second embodiment, the third embodiment further includes the following steps:

[0076] The condensate is subjected to solid-liquid separation to obtain permeate; the solid-liquid separation process is either filtration or centrifugation, thereby removing particulate impurities captured by droplets during the condensation process.

[0077] The permeate is separated using a nanofiltration membrane to obtain an oily liquid. Preferably, the membrane separation process involves vacuum filtration of the permeate at a vacuum level of 100 mmHg and a temperature of 40°C, using a nanofiltration membrane with a pore size of 5 nm. Thus, the nanofiltration membrane allows water to pass through while effectively retaining most organic matter, resulting in the enrichment of most organic matter in the oily liquid.

[0078] An extractant is used to extract an oily liquid to obtain an extractant-soluble liquid; preferably, the extractant is ethanol and / or acetone; the volume of the extractant is twice the volume of the condensate.

[0079] Biomass oil was obtained by vacuum distillation of the extractant-soluble liquid at 50℃ and 16kPa. Vacuum distillation allows the extractant to evaporate and condense, and the condensate obtained can be reused for extracting oily liquids, thus improving the utilization rate of the extractant.

[0080] Unlike the third embodiment, the fourth embodiment of the method for utilizing the exhaust gas from bamboo activated carbon production is as follows:

[0081] The condensate is subjected to solid-liquid separation to obtain permeate; the solid-liquid separation process is either filtration or centrifugation, thereby removing particulate impurities captured by droplets during the condensation process.

[0082] The permeate was extracted with an extractant to obtain a first extractant-soluble liquid.

[0083] The first extractant soluble liquid was subjected to vacuum distillation at 35℃ and 16kPa to obtain a distillate. Vacuum distillation allows the extractant to evaporate and condense. The condensate obtained from vacuum distillation can be reused to extract the permeate, thereby improving the utilization rate of the extractant.

[0084] The distillate is extracted with an extractant and water to obtain a second extractant-soluble liquid. Preferably, in the specific implementation, the extractant is added dropwise while stirring. After the extractant is added, the stirring is continued for 15 minutes. Then, water is added dropwise. After the water is added, the stirring is continued for 30 minutes. Then, the mixture is sealed and allowed to stand for 48 hours. Finally, the second extractant-soluble liquid is obtained through phase separation.

[0085] Biomass oil is obtained by vacuum distillation of the soluble liquid of the second extractant at 35℃ and 16kPa. Vacuum distillation allows the extractant to evaporate and condense, and the condensate obtained from vacuum distillation can be reused to extract the permeate, thereby improving the utilization rate of the extractant.

[0086] The extractant is dichloromethane; preferably, the volume of the extractant is twice the volume of the permeate or the first biomass oil; the volume of water is 1.5 times the volume of the first biomass oil.

[0087] The second embodiment of the method for utilizing the tail gas from bamboo activated carbon production is as follows: Based on the first embodiment, it further includes distilling biomass oil into solid at atmospheric pressure at 200-250℃ (preferably 235℃), and the utilization method further includes crushing, grinding and vacuum drying the solid to obtain solid biomass oil.

[0088] In the third and fourth embodiments, the biomass oil can be further distilled into a solid or concentrate at atmospheric pressure at 200-250°C. For the solid, it is pulverized, ground, and vacuum dried to obtain solid biomass oil. For the concentrate, it is hydrotreated and refined, including the following steps: preparing a reaction solution with a mass ratio of biomass oil:methanol:catalyst of 20:25:1, and hydrothermally reacting it at 190°C and 1 MPa hydrogen pressure for 3 hours to obtain refined biomass oil; using an activated carbon-based Ni / BC catalyst, prepared by dispersing 0.5g of nickel nitrate and 1g of activated carbon in ethanol and stirring for 5 hours; rotary evaporating at 80°C until the ethanol solvent is removed, followed by drying in a vacuum oven; and calcining at 550°C for 2 hours using 20% ​​H₂-Ar as a reducing atmosphere to obtain the activated carbon-based Ni / BC catalyst.

[0089] The embodiments of the invention provided in this specification have been described above. Those skilled in the art will be able to implement the embodiments of the invention provided in this specification based on these descriptions. All other preferred embodiments and implementations obtained by those skilled in the art based on the above description of the embodiments of the invention provided in this specification without inventive effort should fall within the protection scope of the embodiments of the invention provided in this specification.

Claims

1. A system for utilizing production tail gas of bamboo activated carbon, the production tail gas comprising carbonization tail gas produced by a carbonization furnace that carbonizes bamboo raw material and activation tail gas produced by an activation furnace that activates the bamboo raw material after carbonization, wherein an activation agent used for the activation is steam, characterized in that: The utilization system comprises: ​ a condensing device (220) configured to condense the production tail gas to obtain non-condensable gas; a dust removal device (230) configured to remove dust from the non-condensable gas to obtain low-dust gas, wherein the dust removal device (230) is connected to the condensing device (220) at an air inlet thereof; an adsorption device (240) configured to adsorb the low-dust gas to obtain adsorption tail gas, wherein the adsorption device (240) is connected to the dust removal device (230) at an air inlet thereof; a deacidification device (250) configured to deacidify the adsorption tail gas to obtain reaction gas, wherein the deacidification device (250) is connected to the adsorption device (240) at an air inlet thereof; a reaction device (260) configured to have a catalyst packing structure, wherein the reaction gas is catalytically reacted in the reaction device (260) to obtain synthesis gas containing H2, and wherein the reaction device (260) is connected to the deacidification device (250) at an air inlet thereof. 2.The system for utilizing the tail gas produced in the production of bamboo activated carbon according to claim 1, characterized in that: The dust removal device (230) is a filter with a porous metal filter core. 3.The system for utilizing the tail gas produced in the production of bamboo activated carbon according to claim 1, characterized in that: The deacidification device (250) is a spray tower. 4.The system for utilizing the tail gas produced in the production of bamboo activated carbon according to claim 1, characterized in that: The adsorption device (240) is configured to have an activated carbon packing structure. 5.The system for utilizing the tail gas produced in the production of bamboo activated carbon according to claim 1, characterized in that: The utilization system further comprises a first separation device (270) configured to remove CO2 from the reaction gas, and / or a second separation device (280) configured to remove CO2 from the synthesis gas. 6.The system for utilizing the tail gas produced in the production of bamboo activated carbon according to claim 5, characterized in that: The first separation device (270) and the second separation device (280) are both membrane separation devices loaded with a CO2 selective separation membrane, which is any one of a polyetherimide membrane, a polyamide membrane, and a carbon membrane.

7. A system for producing bamboo activated carbon, comprising a carbonization furnace for carbonizing a bamboo raw material and an activation furnace for activating the carbonized bamboo, wherein water vapor is used as an activation agent for the activation treatment, characterized in that: The utilization system further comprises the bamboo activated carbon production tail gas utilization system according to any one of claims 1-6, wherein the production tail gas comprises carbonization tail gas generated by a carbonization furnace and activation tail gas generated by an activation furnace.

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