Water-resistant desulfurization adsorbent for high-humidity blast furnace gas and regeneration method of water-resistant desulfurization adsorbent

Abstract

The invention discloses a water-resistant desulfurization adsorbent for high-humidity blast furnace gas and a regeneration method thereof, and belongs to the technical field of industrial gas purification. The adsorbent has a regional adsorption structure, comprises a hydrophobic phase formed by biomass pyrolytic carbon and a hydrophilic phase formed by active metal oxides in red mud, and solves the problems of serious water vapor competitive adsorption and low COS removal efficiency in a high-humidity environment. The preparation method comprises the following steps: mixing and molding pre-vulcanized red mud powder, biomass powder and an adhesive in proportion, and performing pyrolysis activation in an inert atmosphere. The regeneration method comprises the following step of: purging and regenerating the adsorbent which is saturated by adsorption at 150-400 DEG C by using inert gas. According to the invention, wastes such as red mud and biomass are used as main raw materials, so that the purpose of treating wastes with wastes is realized, and the method has the advantages of high sulfur capacity, good water resistance, strong stability and recyclability.

Description

Technical Field

[0001] This invention belongs to the field of industrial gas purification technology, specifically relating to a water-resistant desulfurization adsorbent for high-humidity blast furnace gas and its regeneration method. Background Technology

[0002] Blast furnace gas is an important secondary energy source generated during steelmaking, but it contains various sulfides, mainly H2S and COS. These sulfides not only corrode downstream pipelines and equipment, but the SO2 emitted after combustion also causes serious environmental pollution. Therefore, deep desulfurization of blast furnace gas before it enters the pipeline network or is used is crucial.

[0003] Currently, dry desulfurization technology is widely researched and applied due to its advantages such as simple process and no wastewater generation. The core of this technology lies in the development of high-performance desulfurization adsorbents. However, blast furnace gas typically possesses complex characteristics such as high humidity (relative humidity often exceeding 90%), large temperature fluctuations (e.g., temperature after TRT is 80~150℃), and the presence of dust, posing a severe challenge to the performance of desulfurization adsorbents. Existing desulfurization adsorbents have the following limitations when applied to this scenario: Severe competitive adsorption of water vapor: High concentrations of water molecules compete strongly with sulfides (especially highly polar H2S) for adsorption at the active sites of the adsorbent. Most common metal oxide adsorbents (such as ZnO and Fe2O3) have hydrophilic surfaces, and water molecules preferentially occupy their active sites, leading to adsorbent "poisoning," a sharp decrease in sulfur capacity and desulfurization efficiency, and a shortened service life.

[0004] The removal efficiency of COS is low: COS has a stable molecular structure and weak polarity, resulting in slow hydrolysis kinetics. Traditional chemisorption-based metal oxide adsorbents have good removal effects on H2S, but their removal capacity for COS is generally poor. Although a process can be used to convert COS to H2S through catalytic hydrolysis before removal, this process is lengthy, requires complex equipment, and the hydrolysis catalyst itself is susceptible to water vapor inhibition.

[0005] Adsorbent cost and secondary pollution issues: High-performance adsorbents typically rely on high-purity active components (such as activated carbon with high specific surface area, molecular sieves, or supported precious metals), resulting in high raw material costs. Furthermore, improper disposal of large quantities of used adsorbents can lead to solid waste pollution, which is inconsistent with the development requirements of a green circular economy.

[0006] To address these issues, existing technologies have explored various approaches. For instance, some studies have attempted to improve the water resistance of adsorbents through surface hydrophobic modification, but this modification process is complex and may clog some pores, affecting mass transfer and sulfur capacity. Other studies have utilized industrial waste (such as fly ash) as adsorbent carriers to reduce costs, but its desulfurization activity, particularly its COS removal capacity, is often limited, making it difficult to meet the stringent requirements for fine desulfurization of blast furnace gas.

[0007] In addition, existing technologies also explore other approaches to improve desulfurizer performance through material composites and structural control. For example, Chinese patent CN120679476A discloses a ZnO / ZnFe2O4 desulfurization adsorbent with a stable porous structure. Using zinc-iron bimetallic hydroxide (ZnFe-LDH) as a precursor, it is decomposed through high-temperature calcination and undergoes a solid-phase reaction to generate a ZnO and spinel-structured ZnFe2O4 composite (with ZnO in excess). Its innovation lies in the use of a mixed solution of organic amine alkaline salt and soluble silicate as a precipitant during preparation. This aims to utilize the gas generated from the decomposition of the organic amine salt for multi-level pore formation and use silica converted from silicate as a binder to stabilize the pore structure at high temperatures, thereby solving the problems of easy sintering and pore structure collapse in pure ZnO desulfurizers during high-temperature regeneration. This technology primarily focuses on improving the thermal and structural stability of materials by constructing metal oxide composite phases. However, this method still requires a high-temperature calcination step to obtain the target active phase, and its structural stability is highly dependent on the amount of silicate additives.

[0008] Chinese patent CN120790093A provides a spherical nickel-iron hydrotalcite phase desulfurization adsorbent and its preparation method. This technology directly synthesizes spherical adsorbents via a one-step hydrothermal carbonization process using a nickel source, an iron source, and an organic carboxylate (such as sodium citrate). The core idea is to utilize the hydroxyl groups on the layers of the hydrotalcite material and the carbonate ions between the layers to provide alkaline sites, thereby enhancing the adsorption of H2S. Simultaneously, the multidentate coordination effect of the organic carboxylate delays hydrotalcite nucleation, promoting the formation of uniformly sized spherical particles. Furthermore, the hydrothermal carbonization process forms a carbon coating layer on the particle surface, thus constructing hierarchical channels to improve mass transfer efficiency. The advantage of this method is its relatively simple process, and the prepared spherical adsorbent is suitable for conditions such as blast furnace gas desulfurization. Although this hydrotalcite adsorbent can be prepared under mild conditions, its long-term high-temperature phase structure stability and regeneration performance still need to be verified. Therefore, developing a desulfurization adsorbent with simpler processing, excellent thermal and structural stability, high adsorption capacity, and good regeneration performance remains a technical problem to be solved in this field. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide a water-resistant desulfurization adsorbent for high-humidity blast furnace gas that combines high efficiency desulfurization, excellent water resistance, and good stability, as well as its preparation method.

[0010] The technical solution adopted by this invention to solve its technical problem is: a water-resistant desulfurization adsorbent for high-humidity blast furnace gas, characterized in that it is prepared by molding and pyrolysis activation using a mixture of red mud and biomass as raw materials; the adsorbent contains a hydrophobic phase composed of biomass-derived carbon materials, which preferentially adsorbs and enriches carbonyl sulfide (COS) in a high-humidity environment; and a hydrophilic phase composed of active metal oxides derived from red mud, which catalyzes the hydrolysis of COS into hydrogen sulfide (H2S) and chemically adsorbs it.

[0011] This invention achieves synergistic and efficient removal of multiple sulfides under high humidity conditions through functional partitioning. The hydrophobic phase, with its hydrophobic properties, effectively repels water molecules from competitive adsorption, preferentially enriching and transferring organic sulfur compounds such as COS. The hydrophilic phase utilizes the catalytic activity of metal oxides to hydrolyze COS and provide chemisorption sites for H2S. This collaborative mechanism not only significantly improves the water resistance and total sulfur capacity of the adsorbent under high humidity conditions, especially the removal efficiency of difficult-to-treat COS, but also integrates adsorption and conversion functions, simplifying the process. Furthermore, this structure uses waste materials such as red mud and biomass as main raw materials, achieving the green and environmentally friendly goals of "waste treatment with waste" and cost reduction while improving performance.

[0012] Preferably, the red mud is pre-sulfurized red mud. The pre-sulfurization treatment includes: preparing a slurry from red mud and water; reacting the slurry with SO2 gas to undergo a pre-sulfurization reaction; and drying and grinding the reacted slurry to obtain red mud powder raw material. The pre-sulfurization treatment, by reacting SO2 with the active metal oxides in the red mud to pre-generate sulfites or sulfates, not only effectively activates the red mud components and optimizes its pore structure to improve mass transfer efficiency, but also significantly enhances the adsorbent's stability and sulfur capacity for removing H2S and COS under high humidity conditions, achieving the dual goals of "waste treatment" and performance improvement.

[0013] Preferably, the raw materials of the adsorbent also include a binder, and the mass ratio of red mud, biomass, and binder is 10:10~50:1~10; the biomass includes at least one of straw, sawdust, and coal powder; the binder includes at least one of starch, tar, and asphalt. The mass ratio of red mud, biomass, and binder ensures that the adsorbent has sufficient mechanical strength and a stable porous structure during molding. After pyrolysis, biomass such as straw and sawdust forms a well-developed hydrophobic carbon skeleton, effectively repelling water molecules and enriching COS. The binder, such as starch and tar, not only ensures the feasibility of the molding process, but its pyrolysis products also help enhance the overall hydrophobicity and pore connectivity. This achieves "waste-to-waste" treatment, reduces costs, and constructs a highly efficient and stable regional adsorption structure.

[0014] Preferably, the active metal oxide includes both the original active metal oxides in the red mud and the added active metal oxides; the original active metal oxides in the red mud include one or more of iron oxide, aluminum oxide, and titanium oxide, with a content of more than 20 wt% of the red mud; the added active metal oxide is one or more of copper oxide, zinc oxide, and manganese oxide, with an addition amount of 1 wt% to 10 wt% of the red mud. By synergistically utilizing the inherent components of red mud and the added highly efficient active components, the adsorbent performance is significantly improved. The original metal oxides in the red mud (such as iron oxide) provide basic adsorption and catalytic sites, ensuring cost advantages and waste utilization; while the added components such as copper oxide and zinc oxide specifically enhance the catalytic hydrolysis ability of COS and the chemical adsorption capacity of H2S. The synergy of the two achieves a comprehensive improvement in the sulfur capacity, water resistance, and catalytic activity of the adsorbent without significantly increasing costs.

[0015] The adsorbent has a dynamic sulfur penetration capacity of not less than 10 mg(S) / g (adsorbent) for COS and not less than 50 mg(S) / g (adsorbent) for H2S.

[0016] Preferably, the water contact angle of the hydrophobic phase is greater than 140°. This characteristic enables the adsorbent surface to effectively repel water molecules, greatly weakening the competitive adsorption of water vapor in high humidity environments, and ensuring that its adsorption sites and capacity for sulfides such as COS remain stable under high humidity.

[0017] Preferably, the adsorbent has a hierarchical pore structure, including macropores and mesopores formed by biomass pyrolysis carbon, and micropores formed by red mud activation. This hierarchical pore structure significantly optimizes the mass transfer pathway and adsorption capacity of the adsorbent. The macropores and mesopores formed by biomass pyrolysis carbon act as high-speed channels, ensuring that COS and H2S molecules in high-flow-rate coal gas can rapidly diffuse into the adsorbent; while the abundant micropores formed by red mud activation greatly increase the specific surface area, providing sufficient active sites. This synergistic effect not only effectively alleviates diffusion limitations and improves desulfurization kinetics, but its structure itself also matches the hydrophobic / hydrophilic functional partitions, jointly ensuring that the adsorbent can still achieve efficient and stable deep desulfurization under harsh conditions of high humidity and high dust.

[0018] The BET specific surface area of ​​the adsorbent is not less than 500 m². 2 / g, porosity greater than 60%.

[0019] The adsorbent also has a heavy metal capture function, capable of adsorbing heavy metal vapors such as mercury (Hg) from blast furnace gas.

[0020] The preparation method of the above-mentioned water-resistant desulfurization adsorbent for high-humidity blast furnace gas includes the following steps: Mixing and molding: The red mud powder is mixed with biomass powder and binder in a certain proportion and then pressed into shape; Pyrolysis activation: Under an inert gas atmosphere or vacuum atmosphere, pyrolysis activation is carried out at 550℃~750℃ for 30min~70min to obtain the product.

[0021] This preparation method synergistically optimizes the microstructure and surface chemistry of the adsorbent through key steps of mixing and controlled pyrolysis. Mixing ensures uniform dispersion and tight composite of red mud, biomass, and binder, laying the foundation for the subsequent formation of stable hierarchical channels. Pyrolysis activation at 550℃~750℃ not only transforms biomass into a hydrophobic carbon framework with well-developed pores, forming a physical adsorption zone, but also promotes the transformation of metal oxides in red mud into a highly active phase, forming a chemical transformation zone. Simultaneously, this process removes some impurities, expands pores, and significantly improves specific surface area and accessibility of active sites. The sulfur-containing gas generated during pyrolysis can be recovered and utilized. This method is simple, with controllable conditions, and effectively achieves the construction and synergy of a "hydrophobic-hydrophilic" partitioned structure, endowing the adsorbent with efficient and stable desulfurization capabilities under high humidity environments. Preferably, before the mixing and molding steps, the biomass is pulverized to a particle size of 100-200 mesh. Pulverizing the biomass to 100-200 mesh significantly increases its specific surface area, laying the foundation for a more developed pore structure in the subsequent pyrolysis activation process. This not only facilitates the uniform loading and dispersion of active components but also optimizes the mass transfer path of the adsorbent, thereby improving its overall adsorption capacity and reaction efficiency for sulfides.

[0022] Preferably, the pyrolysis atmosphere in the pyrolysis activation step is nitrogen. Using a nitrogen atmosphere in the pyrolysis activation step creates an inert environment, effectively preventing the oxidation and combustion of biomass and other raw materials at high temperatures, ensuring their directional transformation into a structurally stable hydrophobic carbon framework, and protecting the active metal components in the red mud from deactivation, thereby synergistically optimizing the pore structure and surface chemical properties of the adsorbent.

[0023] A method for regenerating the above-mentioned water-resistant desulfurization adsorbent for high-humidity blast furnace gas includes the following steps: The adsorbent is packed into a fixed-bed adsorption tower; The blast furnace gas, after dust removal and residual pressure power generation (TRT), is passed into an adsorption tower at a temperature of 60℃~120℃ for desulfurization. After adsorption saturation, the adsorbent is purged and regenerated using an inert gas at 150℃~400℃, and the desorbed sulfur-containing gas is recovered. The regenerated adsorbent is returned to the adsorption tower for reuse.

[0024] This regeneration method deeply integrates adsorption, regeneration, and blast furnace gas purification processes, achieving efficient recycling of the adsorbent and targeted recovery of sulfur resources. The method involves loading the adsorbent into a fixed bed and performing desulfurization within the TRT (Transmitted Refrigerant Tolerance) gas temperature window of 60℃~120℃, ensuring high operating condition matching. After adsorption saturation, purging regeneration is performed using an inert gas (such as nitrogen) at 150℃~400℃. This temperature range effectively desorbs sulfides and avoids damage to the adsorbent structure. The sulfur-containing gas generated during regeneration can be centrally transported to subsequent facilities such as the sintering process for resource recovery, achieving closed-loop sulfur recovery. The entire method realizes the recycling of the adsorbent, significantly extending its service life, reducing operating costs and solid waste generation, and providing an economical and environmentally friendly solution for fine desulfurization of blast furnace gas.

[0025] Compared with existing technologies, the beneficial effects of this invention are as follows: By designing a regional adsorption structure, this invention successfully solves the technical problems of severe water vapor competition adsorption, low COS removal efficiency, and high adsorbent cost in the desulfurization of high-humidity blast furnace gas. This adsorbent uses industrial waste red mud and biomass as main raw materials, achieving "waste-to-waste treatment," significantly reducing raw material costs and avoiding secondary pollution. Its hydrophobic phase effectively repels water molecules and preferentially enriches COS; while the hydrophilic phase efficiently catalyzes COS hydrolysis and chemically adsorbs H2S. The synergistic effect of these two phases ensures that the adsorbent still has high sulfur capacity and excellent stability under high humidity conditions above 90%. The internal multi-level pore structure optimizes the mass transfer path and improves reaction kinetics. The preparation process achieves precise construction of the regional structure through mixing molding and controlled pyrolysis, and the method is simple and controllable. Furthermore, the adsorbent can be regenerated and recycled through inert gas purging, has a long lifespan, and the sulfur-containing gas generated during the regeneration process can be recovered and recycled, forming a closed-loop sulfur management system. This provides an efficient, economical, and environmentally friendly solution for the fine desulfurization of blast furnace gas. Detailed Implementation

[0026] The present invention will be further described below with reference to specific embodiments. These embodiments describe in detail the preferred implementation of the present invention, but are not intended to limit the scope of protection of the present invention. Unless otherwise specified, all parts in the embodiments are parts by weight. Performance tests were conducted under simulated blast furnace gas conditions (H2S 200ppm, COS 50ppm, relative humidity >90%, temperature 100℃, space velocity 3000h). -1 The penetration point is defined as the total sulfur concentration at the outlet exceeding 20 ppm. Example 1

[0027] Pre-sulfurization treatment of red mud: 100 parts of red mud and 500 parts of water were mixed to form a slurry. A 1% SO2 mixed gas was introduced into the slurry at 60℃, and the mixture was stirred and reacted for 2 hours. After the reaction, the mixture was filtered and washed until the filtrate was neutral. The filter cake was dried and ground at 105℃ to obtain pre-sulfurized red mud powder. Subsequently, 50 parts of the pre-sulfurized red mud powder, 30 parts of straw powder crushed to 100 mesh, and 5 parts of starch binder were mixed. After adding an appropriate amount of water and kneading, the mixture was pressed into cylindrical granules with a diameter of 3 mm using a tablet press. The formed granules were dried at 105℃ for 2 hours, and then transferred to a tube furnace. The temperature was increased to 600℃ at a rate of 5℃ / min under a nitrogen atmosphere, and then pyrolyzed and activated at this temperature for 60 minutes. After natural cooling, the adsorbent sample S1 was obtained. The sample was tested and found to have a dynamic sulfur throughput capacity of 12.5 mg(S) / g for COS and 58.3 mg(S) / g for H2S. Its hydrophobic water contact angle was 145°, and its BET specific surface area was 520 m². 2 / g. Example 2

[0028] The preparation method of pre-sulfurized red mud powder is the same as in Example 1. Ten parts of pre-sulfurized red mud powder, ten parts of sawdust powder pulverized to 120 mesh, and one part of tar binder were mixed. After molding, the mixture was pyrolyzed and activated at 550℃ for 70 min under a nitrogen atmosphere to obtain adsorbent sample S2. Test results showed that its COS sulfur penetration capacity was 10.1 mg(S) / g, its H2S sulfur penetration capacity was 50.5 mg(S) / g, and its water contact angle was 142°. Example 3

[0029] The preparation method of pre-sulfurized red mud powder is the same as in Example 1. 10 parts of pre-sulfurized red mud powder, 50 parts of coal powder pulverized to 200 mesh, and 10 parts of asphalt binder are mixed. After molding, the mixture is pyrolyzed and activated at 750℃ for 30 min under a nitrogen atmosphere to obtain adsorbent sample S3. Test results show that its COS sulfur penetration capacity is 11.8 mg(S) / g, and its H2S sulfur penetration capacity is 62.1 mg(S) / g. Sample S3 exhibits a water contact angle of 155°, demonstrating stronger hydrophobicity, and a BET specific surface area as high as 580 m². 2 / g. Example 4

[0030] Based on Example 1, in the mixing step, 1 wt% (i.e., 0.5 parts) of copper oxide powder was added to 50 parts of presulfurized red mud powder, while other conditions remained unchanged, to obtain adsorbent sample S4. Tests showed that its COS breakthrough sulfur capacity was 15.2 mg(S) / g, which was attributed to the strong catalytic effect of CuO on COS hydrolysis, while the H2S breakthrough sulfur capacity remained at 65.5 mg(S) / g. Example 5

[0031] Based on Example 1, in the mixing step, a total of 10 wt% (i.e., 5 parts) of active components were added to 50 parts of presulfurized red mud powder, of which zinc oxide and manganese oxide each accounted for 5 wt%. Other conditions remained unchanged, and adsorbent sample S5 was obtained. Test results showed that its H2S breakthrough sulfur capacity reached 78.3 mg(S) / g, and its COS breakthrough sulfur capacity was also 13.5 mg(S) / g. Example 6

[0032] 100 parts of red mud were mixed with 400 parts of a 1 mol / L dilute sulfuric acid solution and stirred at 80℃ for 2 hours for acid pretreatment. After the reaction, the mixture was filtered, washed until neutral, and dried at 105℃ to obtain acid-pretreated red mud powder. Subsequently, 45 parts of this acid-pretreated red mud powder, 40 parts of coal powder passing through a 200-mesh sieve, and 8 parts of tar binder were weighed and mixed. After adding an appropriate amount of water and kneading, the mixture was extruded into strips with a diameter of 3 mm. After drying at 105℃ for 2 hours, the strips were placed in a tube furnace and heated to 680℃ at a rate of 5℃ / min under a nitrogen atmosphere. The mixture was then pyrolyzed and activated at this temperature for 50 minutes to obtain adsorbent sample S6. Tested under simulated blast furnace gas conditions, sample S6 showed a dynamic sulfur penetration capacity of 13.8 mg(S) / g for COS and 70.5 mg(S) / g for H2S. Its BET specific surface area was 580 m². 2 / g, with a water contact angle of 152°. Example 7

[0033] The red mud pre-sulfurization treatment was the same as in Example 1. 50 parts of pre-sulfurized red mud powder were weighed, and an additional 5 wt% (2.5 parts) of manganese oxide powder was added, along with 35 parts of sawdust powder pulverized to 150 mesh and 5 parts of starch binder. The mixture was pressed into shape and dried at 105°C for 2 hours. Subsequently, it was pyrolyzed and activated at 600°C for 60 minutes under a nitrogen atmosphere to obtain adsorbent sample S7. Under simulated conditions of a lower temperature of 80°C and relative humidity >95%, sample S7 showed a stable COS removal efficiency of 96%, with a COS penetration sulfur capacity of 14.2 mg(S) / g and an H2S penetration sulfur capacity of 65.8 mg(S) / g. Example 8

[0034] The red mud pre-sulfurization treatment was the same as in Example 1. 55 parts of pre-sulfurized red mud powder, 25 parts of straw powder, and 15 parts of pseudoboehmite (as a high-strength inorganic binder) were weighed and mixed. After the materials were mixed and shaped, they were dried according to the steps in Example 1, and then pyrolyzed and activated at 600℃ for 60 min under a nitrogen atmosphere. Post-treatment was performed after pyrolysis: the materials were lightly oxidized in air at 300℃ for 1 h to obtain adsorbent sample S8. The mechanical wear strength test of sample S8 showed that its wear rate was only 1.8%. In the desulfurization performance test, its COS penetration sulfur capacity was 12.0 mg(S) / g, and its H2S penetration sulfur capacity was 60.2 mg(S) / g. After 10 adsorption-regeneration cycles, its sulfur capacity retention rate was 87%. Example 9

[0035] The red mud pre-sulfurization treatment was the same as in Example 1. 50 parts of pre-sulfurized red mud powder, 30 parts of straw powder, and 5 parts of starch binder were weighed and mixed. In addition, 3 parts (6 wt% of the red mud mass) of supported elemental sulfur activated carbon (S-AC) were added. This S-AC had a specific surface area greater than 1000 m². 2 The adsorbent was prepared by impregnating elemental sulfur with activated carbon powder. After thorough mixing of all raw materials, it was shaped and dried according to the steps in Example 1, and then pyrolyzed and activated at 600°C for 60 min under a nitrogen atmosphere to obtain adsorbent sample S9. Desulfurization performance tests showed that sample S9 had a sulfur penetration capacity of 13.0 mg(S) / g for COS and 61.5 mg(S) / g for H2S. In the synergistic mercury removal test, the removal rate of gaseous mercury reached 82%.

[0036] Comparative Example 1 The raw materials and processes were exactly the same as in Example 1, except that the pre-sulfurization treatment step of the red mud was omitted, and the original red mud powder was used directly to prepare the comparative sample D1. The test results showed that its COS sulfur penetration capacity was only 4.8 mg(S) / g, H2S sulfur penetration capacity was 22.1 mg(S) / g, and water contact angle was 110°, which was much lower than that of Example 1.

[0037] Comparative Example 2 The preparation process was exactly the same as in Example 1, but the pyrolysis atmosphere was changed from nitrogen to air, resulting in control sample D2. Sample D2 had poor mechanical strength and a grayish-white color, and tests showed that its sulfur capacity was extremely low (COS: 2.1 mg / g, H2S: 8.5 mg / g). This is because the biomass was burned in the air, failing to form an effective hydrophobic carbon framework, and the active components in the red mud may also have been oxidized and deactivated.

[0038] Example 1: Regeneration Performance Verification The saturated adsorbent sample S1 from Example 1 was regenerated. The saturated adsorbent was packed into a fixed-bed reactor, and nitrogen gas at 300°C was introduced for purging and regeneration for 2 hours. After regeneration, the desulfurization performance was tested again. After five adsorption-regeneration cycles, the breakthrough sulfur capacity retention rate of sample S1 for COS and H2S remained above 85%, indicating that the adsorbent and its regeneration method obtained in this invention have excellent cycle stability and service life.

[0039] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A water-resistant desulfurization adsorbent for high-humidity blast furnace gas, characterized in that, The adsorbent is prepared by molding and pyrolysis activation using a mixture of red mud and biomass as raw materials; the adsorbent consists of a hydrophobic phase composed of biomass-derived carbon materials and a hydrophilic phase composed of active metal oxides derived from red mud.

2. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 1, characterized in that, The red mud is red mud that has undergone pre-sulfurization treatment. The pre-sulfurization treatment includes: preparing red mud and water into a slurry, reacting the slurry with SO2 gas to undergo a pre-sulfurization reaction, and drying and grinding the slurry after the reaction to obtain red mud powder raw material.

3. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 1, characterized in that, The raw materials of the adsorbent also include a binder, and the mass ratio of the red mud, biomass and binder is 10:10~50:1~10; the biomass includes at least one of straw, sawdust and coal powder; the binder includes at least one of starch, tar and asphalt.

4. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 1, characterized in that, The active metal oxides include the original active metal oxides in the red mud and the added active metal oxides; the original active metal oxides in the red mud include one or more of iron oxide, aluminum oxide and titanium oxide, with a content of more than 20 wt% of the red mud; the added active metal oxides are one or more of copper oxide, zinc oxide and manganese oxide, with an addition amount of 1 wt% to 10 wt% of the red mud.

5. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 1, characterized in that, The water contact angle of the hydrophobic phase is greater than 140°.

6. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 1, characterized in that, The adsorbent has a multi-level pore structure, including macropores and mesopores formed by biomass pyrolysis carbon, and micropores formed by red mud activation.

7. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 1, characterized in that, The preparation method includes the following steps: Mixing and molding: The red mud powder is mixed with biomass powder and binder in a certain proportion and then pressed into shape; Pyrolysis activation: Under an inert gas atmosphere or vacuum atmosphere, pyrolysis activation is carried out at 550℃~750℃ for 30min~70min to obtain the product.

8. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 7, characterized in that, Before the mixing and molding steps, the biomass is pulverized to a particle size of 100-200 mesh.

9. The water-resistant desulfurization adsorbent for high-humidity blast furnace gas according to claim 7, characterized in that, In the pyrolysis activation step, the pyrolysis atmosphere is nitrogen.

10. A method for regenerating the water-resistant desulfurization adsorbent for high-humidity blast furnace gas as described in any one of claims 1 to 9, characterized in that, Includes the following steps: The adsorbent is packed into a fixed-bed adsorption tower; The blast furnace gas, after dust removal and residual pressure power generation, is passed into an adsorption tower at a temperature of 60℃~120℃ for desulfurization. After adsorption saturation, the adsorbent is purged and regenerated using an inert gas at 150℃~400℃, and the desorbed sulfur-containing gas is recovered. The regenerated adsorbent is returned to the adsorption tower for reuse.