Utilization method of tail gas in production of bamboo activated carbon and production method of bamboo activated carbon

Abstract

The invention discloses a bamboo activated carbon production tail gas utilization method and a bamboo activated carbon production method.The utilization method comprises the steps that production tail gas is purified to remove water vapor, organic matter steam, volatile organic compounds, acid gas and particulate matter impurities in the production tail gas; in the production tail gas obtained through purification treatment, the volume fraction content of water vapor is 15-25%, the COD content is smaller than or equal to 5 ppm, the volatile organic compound content is smaller than or equal to 3 ppm, the acid gas content is smaller than or equal to 2 ppm, and the particulate matter content is smaller than or equal to 20 mg / Nm < 3 >; the method comprises the following steps: introducing production tail gas into reaction equipment containing a Cu-Zr catalyst, and carrying out catalytic reaction at 240-300 DEG C to generate synthesis gas containing H2. The device can be recycled as an energy source, the external energy consumption of bamboo activated carbon production is reduced, and the comprehensive competitiveness of bamboo activated carbon production is improved.

Description

Technical Field

[0001] The invention relates to the technical field of bamboo activated carbon production, and in particular to a method for utilizing tail gas produced from bamboo activated carbon production and a method for producing bamboo activated carbon. Background Art

[0002] Biomass energy is the fourth largest energy source after coal, oil and natural gas. Biomass energy is energy based on biomass, usually from firewood, straw, livestock manure and urban garbage. Modern technology usually converts these biomass into solid, liquid or gaseous fuels for use. Bamboo energy is an important form of biomass energy, with the advantages of low pollution, wide distribution, large reserves and renewable. my country is the country with the richest bamboo resources in the world and has favorable conditions and environment for the development of bamboo energy.

[0003] At present, an important use of bamboo resources in my country is to prepare bamboo activated carbon. The preparation process mainly includes carbonization process and activation process. The carbonization process can be one or two times. Secondary carbonization usually refers to grinding, kneading, and granulating the primary carbonized material obtained by the first carbonization into special shapes such as columns, honeycombs, and spheres, and then performing secondary carbonization to remove the adhesive used for granulation. In addition to the activation process, which will produce a large amount of exhaust gas, the primary carbonization process and the secondary carbonization will also produce a lot of exhaust gas, and the exhaust gas components produced by the two carbonizations are significantly different.

[0004] In addition to protective gas and water vapor, the tail gas produced by primary carbonization mainly consists of CO, CO generated by pyrolysis of biomass components (such as lignin and hemicellulose). 2 , H 2 , volatile organic compounds (such as alkanes, olefins, aldehydes, etc.), organic vapors (such as terpenes, tannic acid, methanol, etc.), acid gases (such as formic acid, phenol, acetic acid, H 2 S. SO 2 NH 3 , nitrogen oxides, etc.).

[0005] The tail gas produced by secondary carbonization varies greatly depending on the type of adhesive. For example, the main components of the tail gas from secondary carbonization using asphalt or coal tar as adhesive are protective gas, water vapor, CO, CO 2 , volatile organic compounds (such as benzene, toluene, xylene, methylphenol, ethylphenol, etc.) and acid gases (such as phenol, formic acid, acetic acid, aldehydes, nitrogen oxides, etc.), which are highly toxic. When using polymer adhesives (such as starch, molasses, carboxymethyl cellulose, lignin, gelatin, chitosan, etc.), the volatile organic compounds and acid gas content of secondary carbonization tail gas are significantly reduced, and the main components are protective gas, water vapor, CO and CO 2 .

[0006] During the activation process, the activator reacts with the carbon element, causing pore erosion to generate a large number of micropores. The main components of the activated exhaust gas obtained are the protective gas, the activator (such as water vapor, CO 2 , O 2 ), it also contains H 2 , CO, a small amount of volatile organic compounds (such as CH 4 , C 2 H 4 , propylene), acidic gases (such as phenol).

[0007] If the tail gas generated during the carbonization process and the activation process can be converted into clean energy, the utilization rate of bamboo resources can be significantly improved. Chinese invention patent CN116332128A discloses a system for preparing methanol from biomass and co-producing high-quality activated carbon and its preparation method. This method directly performs a water-gas change reaction on the tail gas generated during the activation process, and then performs a CO hydrogenation reaction to finally obtain methanol. On the one hand, a large amount of tail gas generated during the carbonization process is not recycled. On the other hand, directly performing a synthesis reaction on the activated tail gas is likely to cause catalyst poisoning and result in a low purity of methanol. Summary of the invention

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

[0009] In order to achieve the above-mentioned object, according to the first aspect of the present invention, a method and system for utilizing tail gas produced by bamboo activated carbon are provided, and the technical scheme is as follows:

[0010] The invention discloses a method for utilizing tail gas produced by bamboo activated carbon. The tail gas comprises carbonized tail gas generated by carbonizing bamboo raw materials and activated tail gas generated by activation treatment after carbonization. The activating agent used in the activation treatment is water vapor. The utilization method comprises the steps of: purifying the tail gas to remove water vapor, organic vapor, volatile organic matter, acidic gas and particulate impurities in the tail gas. The tail gas obtained after purification has a water vapor volume fraction of 15-25%, a COD content of ≤5ppm, a volatile organic matter content of ≤3ppm, an acidic gas content of ≤2ppm and a particulate matter content of ≤20mg / Nm 3 The production tail gas is passed into a reaction device containing a Cu-Zr catalyst, and a catalytic reaction is carried out at 240-300°C to generate H 2 of synthesis gas.

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

[0012] As a further improvement of the above-mentioned method for utilizing tail gas produced by bamboo activated carbon: it also includes purifying the condensate obtained by the condensation treatment to obtain biomass oil.

[0013] As a further improvement of the above-mentioned method for utilizing tail gas produced by bamboo activated carbon, it also includes using CO before the catalytic reaction. 2 Selective separation membrane to remove CO from production tail gas 2 ; and / or, further comprising using CO after the catalytic reaction 2 Selective separation membrane to remove CO from syngas 2 .

[0014] As a further improvement of the above-mentioned method for utilizing tail gas produced by bamboo activated carbon: a method for preparing a Cu-Zr catalyst comprises the following steps:

[0015] preparing an aqueous solution including urea and a soluble zirconium salt, subjecting the aqueous solution to hydrothermal treatment, and collecting, washing and drying a generated first solid;

[0016] calcining the first solid to obtain a zirconium precursor;

[0017] The zirconium precursor and the copper salt are ground and mixed, and then dispersed in deionized water to form a dispersion, an alkali solution is added to the dispersion under water bath conditions, and the generated second solid is collected, washed and dried;

[0018] The second solid is calcined to obtain a Cu-Zr catalyst.

[0019] As a further improvement to the above-mentioned method for utilizing tail gas produced by bamboo activated carbon: the soluble zirconium salt is zirconium nitrate, 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 of the above-mentioned method for utilizing tail gas produced by bamboo activated carbon: 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 of the above-mentioned method for utilizing tail gas produced by bamboo activated carbon: the copper salt is copper nitrate, and the molar ratio of copper ion to zirconium ion is 0.1-0.15; the water bath temperature is 50-70°C, sodium hydroxide is used as the alkali solution, and after stirring for 1-3 hours under water bath conditions, sodium hydroxide is used to adjust the pH of the dispersion to 9.

[0022] As a further improvement of the above-mentioned method for utilizing tail gas produced by bamboo activated carbon: 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 tail gas produced by bamboo activated carbon, wherein the tail gas produced includes carbonized tail gas generated by a carbonization furnace for carbonizing bamboo raw materials and activated tail gas generated by a cremation furnace for activation after carbonization, wherein the activating agent used for the activation treatment is water vapor, and the utilization system includes: a condensing device, wherein the condensing device performs condensation treatment on the production tail gas to obtain non-condensable gas; a dust removal device, wherein the dust removal device performs dust removal treatment on the non-condensable gas to obtain low-dust gas; the air inlet of the dust removal device is connected to the air outlet of the condensing device; an adsorption device, wherein the adsorption device performs adsorption treatment on the low-dust gas to obtain adsorbed tail gas; the air inlet of the adsorption device is connected to the air outlet of the dust removal device; a deacidification device, wherein the deacidification device performs deacidification treatment on the adsorbed tail gas to obtain reaction gas; the air inlet of the deacidification device is connected to the air outlet of the adsorption device; and a reaction device, wherein a catalyst filler structure is provided in the reaction device, and the reaction gas is catalytically reacted in the reaction device to obtain a gas containing H 2 The gas inlet of the reaction device is connected to the gas outlet of the deacidification device.

[0024] As a further improvement of 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 of the above-mentioned bamboo activated carbon production tail gas utilization system: the deacidification equipment is a spray tower.

[0026] As a further improvement of the above-mentioned bamboo activated carbon production tail gas utilization system: an activated carbon filler structure is provided in the adsorption device.

[0027] As a further improvement of the above-mentioned bamboo activated carbon production tail gas utilization system: it also includes removing CO in the reaction gas 2 A first separation device; and / or, further comprising removing CO from the synthesis gas 2 The second separation device.

[0028] As a further improvement of the above-mentioned bamboo activated carbon production tail gas utilization system: the first separation device and the second separation device are both loaded with CO 2 Membrane separation equipment with selective separation membrane, the CO 2 The selective separation membrane is any one of a polyetherimide membrane, a polyamide membrane, and a carbon membrane.

[0029] In order to achieve the above object, according to the second aspect of the present invention, a bamboo activated carbon production method and production system using the bamboo activated carbon production tail gas utilization method and utilization system described in the first aspect are provided, and the technical scheme is as follows:

[0030] A method for producing bamboo activated carbon, comprising carbonizing and activating bamboo raw materials, and utilizing the production tail gas using the above-mentioned method for utilizing tail gas produced by bamboo activated carbon, wherein the production tail gas comprises carbonized tail gas generated by carbonizing the bamboo raw materials and activated tail gas generated by activating the bamboo raw materials after carbonization;

[0031] The carbonization process comprises the steps of:

[0032] Put the dried bamboo raw material into the carbonization furnace, and raise the furnace temperature from room temperature to 130-280°C in an inert atmosphere, and keep it warm for 0.5-1.5 hours;

[0033] Continue to raise the temperature to 300-400°C and keep it warm for 0.5-1.5 hours;

[0034] Continue to raise the temperature to 500-600°C, keep warm for 0.5-1.5 hours, and then cool with the furnace to obtain the carbonized material;

[0035] The activation treatment is as follows: putting the carbonized material into an activation furnace, in an inert atmosphere, using water vapor as an activating agent, keeping the temperature at 800-1100° C. for 2-4 hours, and then cooling 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 treatment is water vapor. The system also includes a utilization system for the tail gas produced by the bamboo activated carbon. The tail gas produced includes the carbonization tail gas produced by the carbonization furnace and the activation tail gas produced by the activation furnace.

[0037] The present invention has the following advantages:

[0038] (1) Effectively utilize the tail gas generated during the carbonization process (which can be one-time carbonization or two-time carbonization) and activation process of bamboo raw materials, and convert the tail gas into H 2 Synthesis gas (reaction equation: CO+H 2 O→CO 2 +H 2 ), not only reducing the pollution of exhaust emissions to the environment, but also 2 It is a clean energy. On the one hand, it can be recycled as an energy source to reduce the external energy consumption of bamboo activated carbon production and enhance the comprehensive competitiveness of bamboo activated carbon production. On the other hand, it can be used for industrial purposes (such as hydrogen-powered vehicles, oil refining, etc.) and can be sold to increase corporate economic benefits.

[0039] (2) Removing excess water vapor, organic vapor, volatile organic matter, acidic gas and particulate matter impurities from the tail gas before the catalytic reaction can help improve the activity of the catalyst and the efficiency of the catalytic reaction, reduce catalyst poisoning and equipment clogging and wear problems, and produce fewer impurities in the resulting syngas, which helps simplify the subsequent H 2 Purification process. Among them, the condensate obtained after the carbonization tail gas is condensed contains a lot of organic matter, which can be condensed into bio-oil with high calorific value, further generating income for the enterprise.

[0040] The following is a further description of the embodiments of the invention provided in this specification in conjunction with the accompanying drawings and specific implementation methods. Additional aspects and advantages of the embodiments of the invention provided in this specification will be partially given in the following description, and partially will become apparent from the following description, or will be understood through the practice of the embodiments of the invention provided in this specification. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The drawings that constitute part of the embodiments of the inventions provided in this specification are used to assist in understanding the embodiments of the inventions provided in this specification. The contents provided in the drawings and the related descriptions in the embodiments of the inventions provided in this specification can be used to explain the embodiments of the inventions provided in this specification, but do not constitute improper limitations on the embodiments of the inventions provided in this specification. In the drawings:

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

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

[0044] Figure 3 is the XRD pattern of Cu-Zr catalyst.

[0045] The relevant marks in the above drawings 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 DESCRIPTION

[0047] The following is a clear and complete description of the embodiments of the inventions provided in this specification in conjunction with the accompanying drawings. A person of ordinary skill in the art will be able to implement the embodiments of the inventions provided in this specification based on these descriptions. Before describing the embodiments of the inventions provided in this specification in conjunction with the accompanying drawings, it should be particularly noted that:

[0048] The technical solutions and technical features provided in each part of the embodiments of the invention provided in this specification, including the following description, may be combined with each other if there is no conflict.

[0049] In addition, the embodiments of the inventions provided in this specification involved in the following descriptions are generally only a partial embodiment of the embodiments of the inventions provided in this specification rather than all the embodiments. Therefore, based on the embodiments of the inventions provided in this specification, all other embodiments obtained by ordinary technicians in this field without making any creative work should fall within the scope of protection of the embodiments of the inventions provided in this specification.

[0050] Regarding the terms and units in the embodiments of the inventions provided in this specification: The terms "including", "comprising", "having" and any variations thereof in the descriptions and claims of the embodiments of the inventions provided in this specification and in the related parts are intended to cover non-exclusive inclusions. In addition, other relevant terms and units in the embodiments of the inventions provided in this specification can be reasonably interpreted based on the relevant contents of the embodiments of the inventions provided in this specification.

[0051] The first embodiment of the method for producing bamboo activated carbon of the present invention comprises the following steps:

[0052] Drying treatment: Put the fresh bamboo raw materials into an oven and dry them at 100℃ for 48 hours.

[0053] Primary carbonization treatment: put the dried bamboo raw material into the carbonization furnace, and under an inert atmosphere, raise the furnace temperature from room temperature to 200°C and keep it warm for 1 hour; continue to raise the temperature to 350°C and keep it warm for 1 hour; continue to raise the temperature to 550°C and keep it warm for 1 hour, then cool it with the furnace to obtain the carbonized material.

[0054] Activation treatment: put the carbonized material into an activation furnace under an inert atmosphere, use water vapor as an activating agent, and introduce 40 mL of liquid water per 100 g of the green body per hour. After keeping warm at 1000°C for 3 hours, cool it with the furnace to obtain bamboo activated carbon.

[0055] Compared with the first embodiment, the second embodiment of the method for producing bamboo activated carbon of the present invention has the following differences: it also includes a secondary carbonization treatment: the primary carbonized material is ground to a particle size of 325 meshes, and then molasses is used as a binder and water is used as an auxiliary agent, and molasses is used as a binder and water is used as an auxiliary agent. The mass ratio of molasses to the primary carbonized material is 0.5, and 30 mL of auxiliary agent is added to each 100 g of the primary carbonized material. The green body is granulated in a kneader, and the green body is placed in a carbonization furnace. In an inert atmosphere, the furnace temperature is raised from room temperature to 550° C., and the temperature is kept for 1 hour. The secondary carbonized material is cooled with the furnace to obtain the secondary carbonized material. Then, the secondary carbonized material is activated to obtain bamboo activated carbon.

[0056] The method for utilizing bamboo activated carbon production tail gas of the present invention is used to utilize the production tail gas generated by the bamboo activated carbon production method described in the first embodiment or the second embodiment above, that is, the production tail gas includes carbonization tail gas generated by a primary carbonization treatment or a primary carbonization treatment and a secondary carbonization treatment and activation tail gas generated by activation treatment after carbonization.

[0057] The first embodiment of the method for utilizing tail gas produced by bamboo activated carbon comprises the following steps:

[0058] The production tail gas is purified to remove water vapor, organic vapor, volatile organic matter, acidic gas and particulate impurities in the production tail gas. The purification treatment includes condensation treatment, dust removal treatment, adsorption treatment and deacidification treatment of the production tail gas in sequence. Among them, water vapor, organic vapor and low-boiling acidic gas in the production tail gas can be removed by condensation treatment. The dust removal treatment is preferably filtration dust removal. The volatile organic matter in the production tail gas can be adsorbed by adsorption treatment, and activated carbon is preferably used as an adsorbent. The residual acid gas in the production tail gas can be removed by deacidification treatment. The deacidification treatment preferably uses a spray tower for wet deacidification, and deacidification is performed by circulating spraying liquid absorbent. Thus, the water vapor volume fraction content in the production tail gas obtained after purification treatment is 15-25%, the COD content is ≤5ppm, the volatile organic content is ≤3ppm, the acid gas content is ≤2ppm, and the particulate content is ≤20mg / Nm 3 .

[0059] The production tail gas is passed into a reaction device containing a Cu-Zr catalyst to undergo a catalytic reaction at 240-300°C to generate H 2 of synthesis gas.

[0060] The second embodiment of the method for utilizing tail gas produced by bamboo activated carbon is as follows: based on the first embodiment, the method further comprises using CO before the catalytic reaction. 2 Selective separation membrane to remove CO from production tail gas 2 and the use of CO after the catalytic reaction 2 Selective separation membrane to remove CO from syngas2 .

[0061] Figure 1 The structure diagram of the first embodiment of the bamboo activated carbon production system and the bamboo activated carbon production tail gas utilization system. Figure 1 As shown, the bamboo activated carbon production system includes a carbonization furnace (1 or 2) for carbonizing the bamboo raw materials, an activation furnace for activating the bamboo raw materials after carbonization, and a production exhaust gas utilization system, wherein the production exhaust gas includes the carbonization exhaust gas discharged from 1 or 2 carbonization furnaces and the activation exhaust gas discharged from the activation furnace.

[0062] The first embodiment of the utilization system of tail gas produced by bamboo activated carbon includes a gas collecting tank 210 , a condensing 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 tail gas, and the gas outlet of the gas collecting tank 210 is connected to the gas inlet of the condensing device 220. The condensing device 220 condenses the production tail gas to obtain non-condensable gas. The dust removal device 230 performs dust removal on the non-condensable gas to obtain low-dust gas. The air inlet of the dust removal device 230 is connected to the air outlet of the condensing device 220. The dust removal device 230 is a filter using a porous metal filter element. The adsorption device 240 performs adsorption on the low-dust gas to obtain adsorbed tail gas; the air inlet of the adsorption device 240 is connected to the air outlet of the dust removal device 230, and the adsorption device 240 is provided with an activated carbon filler structure. The deacidification device 250 performs deacidification treatment on the adsorbed tail gas to obtain a reaction gas; the air inlet of the deacidification device 250 is connected to the air outlet of the adsorption device 240; the deacidification device 250 is a spray tower using wet deacidification, which performs deacidification by spraying a liquid absorbent and can increase the humidity of the reaction gas to make it more suitable for H 2 The reaction device 260 is provided with a catalyst packing structure, and the reaction gas is catalytically reacted in the reaction device 260 to obtain a catalyst containing H 2 The gas inlet of the reaction device 260 is connected to the gas outlet of the deacidification device 250.

[0064] Figure 2 The structure diagram of the second embodiment of the bamboo activated carbon production system and the bamboo activated carbon production tail gas utilization system. Figure 2 As shown, compared with the first embodiment, the utilization system of the second embodiment further includes removing CO from the reaction gas. 2 The first separation device 270 and the removal of CO from the synthesis gas 2 The first separation device 270 and the second separation device 280 are both loaded with CO 2Membrane separation equipment with selective separation membrane, the CO 2 The selective separation membrane is any one of a polyetherimide membrane, a polyamide membrane, and a carbon membrane. 2 It helps maintain the activity of the catalyst, but too much will inhibit the H2 synthesis reaction. Therefore, the first separation device 270 removes excess CO 2 , making CO 2 Reducing the volume fraction to 2-5% can promote the reaction toward H 2 The second separation device 280 removes CO from the synthesis gas. 2 , which can improve H 2 purity.

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

[0066] Dissolving zirconium nitrate and urea in 150 mL of deionized water to form an aqueous solution, wherein the molar ratio of urea to zirconium ions in the aqueous solution is 2, and the zirconium ion concentration is 0.2 mol / L; subjecting the aqueous solution to a hydrothermal treatment at a hydrothermal reaction temperature of 150° C. for 24 hours, and collecting, washing and drying the generated first solid;

[0067] calcining the first solid at a temperature of 250° C. for 4 hours to obtain a zirconium precursor;

[0068] The zirconium precursor and copper nitrate are ground and mixed, and the molar ratio of copper ions to zirconium ions (calculated according to zirconium nitrate) is 0.12; then the ground mixture is dispersed in 200 mL of deionized water to form a dispersion, and stirred for 2 hours in a water bath at a water bath temperature of 60° C., and sodium hydroxide is slowly added to the dispersion in a water bath until the pH of the dispersion reaches 9, and the generated second solid is collected, washed and dried;

[0069] The second solid was calcined at a temperature of 400° C. for 4 hours to obtain a Cu-Zr catalyst.

[0070] Figure 3 is the XRD pattern of Cu-Zr catalyst. Figure 3 As shown, the Cu-Zr catalyst has a good crystal structure, and its XRD pattern has CuO x and ZrO 2 The characteristic peaks of Cu in the preparation process are not embedded into the zirconium precursor (ZrO 2 ), but CuOx is uniformly attached to ZrO 2 The surface produces a better catalytic effect through the interaction between the two.

[0071] By N 2The zirconium precursor (ZrO 2 ) has a specific surface area of ​​37.35 m 2 / g, with a total pore volume of 0.22cm 3 / g, the average pore size is 23.6nm, and the specific surface area of ​​the Cu-Zr catalyst is 56.48m 2 / g, with a total pore volume of 0.30 cm 3 / g, the average pore size is 21.8nm, it can be seen that when CuO is loaded x After that, the specific surface area of ​​the Cu-Zr catalyst increased significantly, which plays a decisive role in the adsorption and activation of the gas.

[0072] The volume fractions were divided into 15% CO, 40% H 2 、35%N 2 , 10% CO 2 The mixed gas was mixed with water vapor and catalyzed by Cu-Zr catalyst at 180-300℃. The results showed that the CO conversion rate increased sharply at first and then gradually tended to be gentle with the increase of catalytic temperature. The corresponding CO conversion rates at 180℃, 210℃, 240℃, 270℃ and 300℃ were 62%, 79%, 85%, 86% and 87%, respectively.

[0073] The Cu-Zr catalyst is used to treat the reaction gas (one embodiment data: 21.54% CO, 3.14% CO) after being treated by the first separation device 270. 2 、23.55%H 2 , 22.35% water vapor, the balance is N 2 ) for catalysis, the reaction temperature was 270°C, the reaction pressure was 5MPa, and the space velocity was 5000h -1 , CO conversion rate is 81%.

[0074] It can be seen that the preparation method of the Cu-Zr catalyst used is simple, and the obtained Cu-Zr catalyst has high catalytic activity and stability, and can promote the reaction of CO and water vapor at a lower temperature, which helps to improve the stability of the synthesis gas production process and reduce the frequency of catalyst renewal, thereby saving long-term operating costs. The effective conversion of tail gas from bamboo activated carbon production through catalytic reaction technology is an innovative green chemical process, which is in line with the global trend of promoting green production and reducing carbon emissions, and has a significant promotion effect on the development and application of bamboo resources.

[0075] The condensate obtained after the carbonization tail gas is condensed contains a large amount of organic matter, which can be condensed into bio-oil with high calorific value. In order to deeply recover the valuable resources of the production tail gas, the method for utilizing the tail gas produced by bamboo activated carbon of the present invention further utilizes the condensate recovered by the condensation equipment. On the basis of the second embodiment, the third embodiment further includes the steps of:

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

[0077] The permeate is subjected to membrane separation treatment using a nanofiltration membrane to obtain an oily liquid; preferably, the membrane separation treatment is a vacuum filtration treatment of the permeate, the vacuum degree is 100 mmHg, the temperature is 40°C, and the pore size of the nanofiltration membrane is 5 nm. Thus, the nanofiltration membrane can allow water to pass through, while most of the organic matter is effectively intercepted, so that most of the organic matter is enriched in the oily liquid.

[0078] The oily liquid is subjected to extraction treatment with an extractant to obtain an extractant-soluble liquid; preferably, the extractant is ethanol and / or acetone; and the volume of the extractant is twice the volume of the condensate.

[0079] The extractant-soluble liquid is subjected to vacuum distillation at 50°C and 16 kPa to obtain biomass oil. The extractant can be evaporated and condensed by vacuum distillation, and the condensate obtained by vacuum distillation can be repeatedly used for extraction of oily liquid, which can improve the utilization rate of the extractant.

[0080] Different from the third embodiment, the fourth embodiment of the method for utilizing tail gas produced by bamboo activated carbon is as follows:

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

[0082] The permeate is subjected to extraction treatment by using an extractant to obtain a first extractant-soluble liquid.

[0083] The first extractant soluble liquid is subjected to reduced pressure distillation at 35°C and 16kPa to obtain a distillate; the extractant can be evaporated and condensed by the reduced pressure distillation, and the condensate obtained by the reduced pressure distillation is repeatedly used for extraction of the permeate, which can improve 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, stirring is maintained, the extractant is first added dropwise, stirring is maintained for 15 minutes after the addition of the extractant is completed, and then water is added dropwise, stirring is continued for 30 minutes after the addition of water is completed, and then the mixture is sealed and allowed to stand for 48 hours, and finally the second extractant-soluble liquid is obtained by phase separation.

[0085] The second extractant soluble liquid is subjected to vacuum distillation at 35°C and 16kPa to obtain biomass oil. The vacuum distillation can evaporate and condense the extractant, and the condensate obtained by the vacuum distillation can be repeatedly used for extraction of the permeate, which can improve 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 tail gas produced by bamboo activated carbon is as follows: based on the first embodiment, it also includes distilling the biomass oil into a solid at 200-250°C (preferably 235°C) under normal pressure, and the utilization method also 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 at 200-250°C to form a solid or a concentrated liquid. For the solid, the solid is crushed, ground and vacuum dried to obtain solid biomass oil; for the concentrated liquid, the concentrated liquid is subjected to a hydrogenation refining treatment, including the steps of: preparing a reaction liquid according to a mass ratio of biomass oil: methanol: catalyst of 20:25:1, and hydrothermally reacting at 190°C and 1MPa hydrogen pressure for 3h to obtain refined biomass oil; using an activated carbon-based Ni / BC catalyst, the preparation method of which is: dispersing 0.5g nickel nitrate and 1g activated carbon in ethanol, stirring for 5h; rotary evaporation at 80°C to completely remove the ethanol solvent and then drying in a vacuum oven; heating at 20% H 2 -Ar was used as a reducing atmosphere and calcined at 550 °C for 2 h to obtain the activated carbon-based Ni / BC catalyst.

[0089] The above is a description of the relevant contents of the embodiments of the inventions provided in this specification. Based on these descriptions, a person of ordinary skill in the art will be able to implement the embodiments of the inventions provided in this specification. Based on the above contents of the embodiments of the inventions provided in this specification, all other preferred implementations and embodiments obtained by a person of ordinary skill in the art without making any creative work shall fall within the scope of protection of the embodiments of the inventions provided in this specification.

Claims

1. A method for utilizing tail gas produced by bamboo activated carbon, wherein the tail gas produced includes carbonized tail gas produced by carbonizing bamboo raw materials and activated tail gas produced by activation treatment after carbonization, wherein the activating agent used in the activation treatment is water vapor, and the method is characterized in that: The method of use includes the following steps: The production tail gas is purified to remove water vapor, organic vapor, volatile organic matter, acidic gas and particulate impurities in the production tail gas. The water vapor volume fraction in the production tail gas obtained after purification is 15-25%, COD content ≤5ppm, volatile organic matter content ≤3ppm, acidic gas content ≤2ppm, and particulate matter content ≤20mg / Nm 3 ; The production tail gas is introduced into a reaction device containing a Cu-Zr catalyst, and a catalytic reaction is carried out at 240-300°C to generate a synthesis gas containing H2.

2. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 1, characterized in that: The purification treatment includes sequentially performing condensation treatment, dust removal treatment, adsorption treatment and deacidification treatment on the production tail gas; the deacidification treatment adopts wet deacidification.

3. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 2, characterized in that: The method also includes purifying the condensate obtained by the condensation treatment to obtain biomass oil.

4. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 3, characterized in that: It also includes using a CO2 selective separation membrane to remove CO2 from the production tail gas before the catalytic reaction; and / or, it also includes using a CO2 selective separation membrane to remove CO2 from the synthesis gas after the catalytic reaction.

5. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 1, characterized in that: The preparation method of the Cu-Zr catalyst comprises the following steps: preparing an aqueous solution including urea and a soluble zirconium salt, subjecting the aqueous solution to hydrothermal treatment, and collecting, washing and drying a generated first solid; calcining the first solid to obtain a zirconium precursor; The zirconium precursor and the copper salt are ground and mixed, and then dispersed in deionized water to form a dispersion, an alkali solution is added to the dispersion under water bath conditions, and the generated second solid is collected, washed and dried; The second solid is calcined to obtain a Cu-Zr catalyst.

6. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 5, characterized in that: 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.

7. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 5, characterized in that: The calcination temperature for calcining the first solid is 230-270° C., and the calcination time is 3-5 hours.

8. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 5, characterized in that: The copper salt is copper nitrate, and the molar ratio of copper ion to zirconium ion is 0.1-0.15; the water bath temperature is 50-70°C, sodium hydroxide is used as the alkali solution, and after stirring for 1-3 hours under water bath conditions, sodium hydroxide is used to adjust the pH of the dispersion to 9.

9. The method for utilizing tail gas produced by bamboo activated carbon production as claimed in claim 5, characterized in that: The calcination temperature for calcining the second solid is 350-450° C., and the calcination time is 3-5 hours.

10. A method for producing bamboo activated carbon, comprising carbonizing and activating bamboo raw materials, characterized in that: The method also includes utilizing the production tail gas of bamboo activated carbon according to any one of claims 1 to 9, wherein the production tail gas includes carbonized tail gas generated by carbonizing bamboo raw materials and activated tail gas generated by activation treatment after carbonization; The carbonization process comprises the steps of: Put the dried bamboo raw material into the carbonization furnace, and raise the furnace temperature from room temperature to 130-280°C in an inert atmosphere, and keep it warm for 0.5-1.5 hours; Continue to raise the temperature to 300-400°C and keep it warm for 0.5-1.5 hours; Continue to raise the temperature to 500-600°C, keep warm for 0.5-1.5 hours, and then cool with the furnace to obtain the carbonized material; The activation treatment is as follows: putting the carbonized material into an activation furnace, in an inert atmosphere, using water vapor as an activating agent, keeping the temperature at 800-1100° C. for 2-4 hours, and then cooling with the furnace to obtain bamboo activated carbon.

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