Method for producing aluminoferrite cement by using hydrogen energy

Abstract

The invention discloses a method for producing iron aluminate cement by using hydrogen energy, which belongs to the technical field of low carbon, and comprises the following steps: calcining raw material powder to obtain clinker, and grinding the clinker, a mixed material and gypsum to obtain the iron aluminate cement, the raw material calcination fuel is mixed gas of hydrogen and natural gas; the recovered carbon dioxide and hydrogen are used for synthesizing methanol through a high-efficiency catalyst, and the prepared methanol is used for preparing the high-efficiency catalyst. Hydrogen energy is selected as a core heat source for raw material calcination, and compared with traditional fossil fuel, carbon emission paths are reduced fundamentally, and negative effects of greenhouse gas emission on global climate can be relieved. In addition, by accurately adjusting the volume ratio of the hydrogen to the natural gas, fine regulation and control of the calcination temperature can be achieved. Recycling of carbon dioxide in tail gas is used as a key technical link. And carbon dioxide is efficiently separated from complex components of the tail gas, so that the total carbon emission amount is further reduced.

Description

Technical Field

[0001] The present invention relates to the field of low-carbon technology, in particular to a method for producing ferroaluminate cement by utilizing hydrogen energy. Background Art

[0002] The calcination of cement raw materials primarily relies on fossil fuels such as coal and heavy oil. The combustion of these fuels inevitably releases vast amounts of carbon dioxide. Cement production is large-scale, and the continued high carbon emissions have a significant impact on the ecological environment, exacerbating the greenhouse effect and exacerbating global warming. Although carbon emissions from the production of ferroaluminate cement are approximately 40% lower than those of ordinary cement, its exhaust gases are rich in carbon dioxide. Direct emissions cause large amounts of carbon dioxide to enter the atmosphere, significantly increasing total carbon emissions and further deteriorating the environment. Although some technologies have attempted to recycle exhaust carbon dioxide, the recovery process is complex and inefficient, and subsequent utilization options are extremely limited, making it impossible to form an efficient resource recycling model. Throughout ferroaluminate cement production and related chemical processes, there is a serious lack of an energy recycling system, with each link being fragmented and the comprehensive resource utilization rate being low. This not only wastes resources but also hinders the sustainable development of the industry. Summary of the Invention

[0003] In view of the above-mentioned shortcomings of the prior art, the present invention provides a method for producing ferroaluminate cement using hydrogen energy.

[0004] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0005] The method for producing ferroaluminate cement using hydrogen energy comprises the following steps: mixing a calcium raw material, an aluminum raw material, an iron raw material, and a sulfur raw material in a mass ratio of 5:2:3:1, ball milling to obtain raw meal powder, calcining the raw meal powder to obtain clinker, and grinding the clinker, a mixed material (slag and fly ash in a mass ratio of 6:4), and gypsum in a mass ratio of 70:25:10 to obtain ferroaluminate cement;

[0006] The method is characterized in that after the raw material is fed into a hydrogen sintering furnace, hydrogen and natural gas are mixed in a volume ratio of 1:0.4-0.6 and then calcined in a gradient manner for 2-3 hours;

[0007] The carbon dioxide and hydrogen recovered from the hydrogen sintering furnace are introduced into a fixed bed reactor equipped with a high-efficiency catalyst at a molar ratio of 1:3.5-4. The reaction temperature is controlled at 200-250°C, the pressure is 1-3 MPa, and the gas space velocity is 1000-1500. At the same time, the methanol produced is used in the preparation of high-efficiency catalysts;

[0008] The preparation of high-efficiency catalyst includes the following steps:

[0009] S1 dissolution: crush the copper slag and zinc tailings, immerse them in a sulfuric acid methanol solution, heat and pressurize to leach the copper and zinc, and filter to obtain a mixed metal solution and a filter residue with the leached metal;

[0010] The filter residue is added to the mixed material at 3-5% of the mass of the calcium raw material;

[0011] S2 impurity removal: introduce oxygen into the mixed metal solution and react for 30-40 minutes. Oxidized to , adjust the solution pH to 3.8-4.2, by Form precipitation, control the stirring speed to 100-200r / min to promote floc growth, and remove the precipitate by centrifugation to obtain a copper-zinc mixed solution;

[0012] S3 crystallization: add sodium carbonate solution to the copper-zinc mixture and adjust the pH of the solution to and Synchronously generate basic carbonate, add citric acid as a complexing agent, and age to obtain a Cu-Zn precursor;

[0013] S4 washing and drying: After the precipitate is aged, it is centrifuged and washed 2-3 times with 50-60℃ deionized water to remove the residual and Ions, add 1 / 10 of the deionized water mass of anhydrous ethanol during the final wash to replace the surface moisture of the particles and reduce hydrogen bond agglomeration during the drying process; dry at 50-60°C;

[0014] S5 support activation: placing the boron nitride nanosheets in a sodium hydroxide solution, ultrasonically treating to remove surface impurities and oxides, washing and drying to obtain activated boron nitride nanosheets;

[0015] S6 Precursor-Carrier Composite: Add 2-3% by mass of carboxymethyl cellulose as a binder to the Cu-Zn precursor and stir evenly to form a paste with good plasticity and a solid content of 65-75%. Use a spray drying method to prepare spherical particles with a particle size of 50-100μm under the conditions of an inlet air temperature of 180-200℃ and an outlet air temperature of 90-100℃, so that the precursor is evenly loaded on the carrier surface. The mass ratio of the activated boron nitride nanosheet carrier to the Cu-Zn precursor is 2-4:1;

[0016] S7 crystal shape control: Place the spherical particles in a high-temperature tube furnace and heat them from room temperature to 300-350°C at a heating rate of 3-4°C / min. Maintain the temperature in an argon and hydrogen mixture (hydrogen content 5-8%) for 1-1.5 hours to initially remove organic impurities. Then, continue heating to 550-600°C at a heating rate of 2-3°C / min and calcine for 30-50 minutes to convert the basic carbonate into CuO-ZnO composite oxide.

[0017] S8 Reduction: Place the CuO-ZnO composite oxide in an atomic layer deposition apparatus, introduce diethylzinc, an organic precursor of zinc, and hydrogen in sequence to deposit a layer of zinc atoms on the surface of the CuO-ZnO composite oxide. Then switch to a methanol-hydrogen mixed gas to preliminarily reduce part of the CuO and form Cu / ZnO active centers on the CuO-ZnO composite oxide.

[0018] S9 carbonization: After the temperature of the reactor is lowered, acetylene gas is introduced. Acetylene is pyrolyzed and carbonized on the surface of the CuO-ZnO composite oxide to form a carbon film to obtain a high-efficiency catalyst.

[0019] Furthermore, after the raw meal is fed into a hydrogen sintering furnace, hydrogen and natural gas are mixed at a volume ratio of 1:0.4-0.6 and then calcined in a gradient manner;

[0020] Stage 1: calcination temperature 1250-1280℃ (material temperature), time 40-60min;

[0021] Stage 2: calcination temperature 1280-1320℃ (material temperature), time 40-60min;

[0022] Stage 3: calcination temperature 1320-1350℃ (material temperature), time 40-60min.

[0023] Furthermore, the carbon dioxide recovery method is specifically as follows: a high-efficiency carbon dioxide absorption tower is installed at the exhaust gas outlet of the hydrogen sintering furnace, ethanolamine solution is used as the absorbent, the temperature of the absorption tower is controlled at 40-50°C, and the saturated ethanolamine solution is desorbed into high-purity carbon dioxide through a desorption tower at 100-120°C and 0.1-0.2MPa.

[0024] Furthermore, S1 dissolution: the copper slag and zinc tailings are crushed to 100-200 mesh, immersed in a methanol solution with a sulfuric acid concentration of 20-30%, maintained at a pressure of 0.2-0.5 MPa in a closed reactor, and kept warm at 70-80°C for 1-2 hours to leach copper and zinc, and filtered to obtain a mixed metal solution and a filter residue from which the metal has been leached.

[0025] Furthermore, S3 is specifically as follows: adding a 1.5-2.0 mol / L sodium carbonate solution preheated to 50-60°C to the copper-zinc mixture at a rate of 6-10 drops / min, adjusting the solution pH to 8-10, and Basic carbonate is generated synchronously, and the stirring speed is controlled at 200-400 r / min to avoid local oversaturation resulting in uneven particle size. At the same time, citric acid, a complexing agent, is added at a concentration of 0.5-2% by mass of the copper-zinc mixture to inhibit excessive grain growth and agglomeration through coordination. The mixture is aged for 40-60 minutes to promote the directional growth of the crystal nucleus to obtain a Cu-Zn precursor.

[0026] Furthermore, S5 is specifically as follows: placing the boron nitride nanosheets in a sodium hydroxide solution with a concentration of 0.2-0.3 mol / L, ultrasonically treating at 40-50°C for 1-2 hours to remove surface impurities and oxides, then washing with deionized water multiple times until neutral, and vacuum drying at 100-150°C to obtain activated boron nitride nanosheets.

[0027] Furthermore, S6 is specifically as follows: adding 2-3% by mass of carboxymethyl cellulose as a binder to the Cu-Zn precursor, stirring evenly to form a paste with good plasticity and a solid content of 65-75%, and spray drying the paste under the conditions of an inlet air temperature of 180-200°C and an outlet air temperature of 90-100°C, into spherical particles with a particle size of 50-100μm, so that the precursor is evenly loaded on the surface of the carrier, and the mass ratio of the activated boron nitride nanosheet carrier and the Cu-Zn precursor is 2-4:1.

[0028] Furthermore, S7 is specifically as follows: the spherical particles are placed in a high-temperature tube furnace, the temperature is raised from room temperature to 300-350°C at a heating rate of 3-4°C / min, and the temperature is kept in a mixed atmosphere of argon and hydrogen for 1-1.5 hours to preliminarily remove organic impurities; then the temperature is continued to be raised to 550-600°C at a heating rate of 2-3°C / min, and calcined for 30-50 minutes to promote the conversion of basic carbonate into CuO-ZnO composite oxide.

[0029] Furthermore, S8 is specifically as follows: placing the CuO-ZnO composite oxide into an atomic layer deposition device, introducing diethylzinc and hydrogen, an organic precursor of zinc, in sequence, performing atomic layer deposition at 120-130°C, depositing a layer of zinc atoms on the surface of the CuO-ZnO composite oxide, then switching to a methanol-hydrogen mixture, and keeping warm at 250-280°C for 30-50 minutes. At the same time, the atomically deposited zinc atomic layer is used to induce the directional growth and dispersion of copper atoms, preliminarily reduce part of the CuO, and form a Cu / ZnO active center on the CuO-ZnO composite oxide.

[0030] Furthermore, S9 is specifically as follows: when the temperature of the reactor drops to 150-170°C, acetylene gas is introduced with a flow rate controlled at 30-50 mL / min, and the reaction is carried out for 15-20 minutes. Acetylene is pyrolyzed and carbonized on the surface of the CuO-ZnO composite oxide to form a carbon film, thereby obtaining a highly efficient catalyst.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention uses hydrogen and natural gas as the core heat sources for raw material calcination. Only water is produced during the hydrogen combustion process, and almost no carbon emissions are generated. Compared with traditional fossil fuels, this effectively reduces the carbon emission path and can alleviate the negative impact of greenhouse gas emissions on the global climate. In addition, by accurately adjusting the volume ratio of hydrogen and natural gas, fine regulation of the calcination temperature can be achieved. In industrial production, different raw materials have strict and subtle requirements for calcination temperature. The temperature control method of the present invention can accurately match the characteristics of the raw materials and ensure that the raw materials complete the calcination reaction within the most suitable temperature range. This not only makes the raw material calcination more sufficient and improves the uniformity of product quality, but also avoids product defects caused by temperature fluctuations, thereby improving production efficiency and reducing the defective rate, effectively ensuring the stability and efficiency of the entire production process, and providing strong support for the green upgrade of related industries.

[0033] 2. This invention utilizes the recovery and utilization of carbon dioxide from tail gas as a key technical link. By efficiently separating carbon dioxide from the complex components of tail gas, total carbon emissions are further reduced. Using the specially formulated high-efficiency catalyst of this invention, the recovered carbon dioxide can be efficiently converted into high-purity methanol. This catalyst, with its unique structural design and active site construction, precisely adsorbs carbon dioxide molecules and promotes their reaction with hydrogen. Compared with similar catalysts on the market, it significantly suppresses side reactions, increasing the reaction system's focus on methanol production. It also significantly increases the carbon dioxide conversion rate by significantly increasing the amount of carbon dioxide reacting per unit time. Furthermore, the methanol space-time yield significantly increases the amount of methanol produced per unit time and per unit mass of catalyst. Most importantly, the synthesized methanol can serve as a high-quality solvent for the high-efficiency catalyst feedstock. This innovative application establishes a closed-loop system for energy recycling. From the recovery of tail gas carbon dioxide to the synthesis of methanol and then to the preparation of the methanol-feeding catalyst, the entire process is seamlessly integrated, greatly improving the comprehensive utilization of resources and opening up a new path for the sustainable development of the chemical industry.

[0034] 3. In the preparation process of the high-efficiency catalyst of the present invention, waste residue is no longer regarded as a production burden, but is converted into a highly valuable secondary resource, thereby successfully achieving an improvement in cement strength. This measure not only improves the mechanical properties of cement products and broadens its application areas, but also significantly reduces the emission of waste residue. The proper treatment of waste residue avoids the potential pollution risks of traditional landfill or stacking methods to soil, water and air, and at the same time achieves the recycling of energy. The waste residue originally generated by the energy consumption in the preparation of the catalyst can be reused in the cement production process, reducing the demand for other raw materials in the cement production process, indirectly reducing energy consumption, and fully demonstrating the advanced characteristics of the present invention of green environmental protection and efficient resource utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0036] Figure 1 This is a process flow chart for producing ferroaluminate cement using hydrogen energy. DETAILED DESCRIPTION

[0037] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0038] Example 1: This example provides a method for producing ferroaluminate cement using hydrogen energy, comprising the following steps: mixing a calcium raw material, an aluminum raw material, an iron raw material, and a sulfur raw material in a mass ratio of 5:2:3:1, ball milling to obtain raw meal powder, calcining the raw meal powder to obtain clinker, and grinding the clinker, a mixed material (slag and fly ash in a mass ratio of 6:4), and gypsum in a mass ratio of 70:25:10 to obtain ferroaluminate cement;

[0039] Among them, after the raw material is fed into the hydrogen sintering furnace, hydrogen and natural gas are mixed in a volume ratio of 1:0.4-0.6 and then calcined in a gradient manner;

[0040] Stage 1: When the volume ratio of hydrogen to natural gas is 1:0.6, the calcination temperature is 1280°C and the time is 60 min;

[0041] Stage 2: When the volume ratio of hydrogen to natural gas is 1:0.5, the calcination temperature is 1320°C and the time is 60 min;

[0042] Stage 3: When the volume ratio of hydrogen to natural gas is 1:0.4, the calcination temperature is 1350°C and the time is 60 min;

[0043] Carbon dioxide recovery: An efficient carbon dioxide absorption tower is installed at the exhaust gas outlet of the sintering furnace. Ethanolamine solution is used as the absorbent. The temperature of the absorption tower is controlled at 50°C. The saturated ethanolamine solution is desorbed into high-purity carbon dioxide through a desorption tower at 120°C and 0.2MPa.

[0044] Carbon dioxide and hydrogen were introduced into a fixed bed reactor equipped with a high-efficiency catalyst at a molar ratio of 1:4. The reaction temperature was controlled at 250°C, the pressure was 3 MPa, and the gas space velocity was 1500 At the same time, the methanol produced can be used in the preparation of high-efficiency catalysts;

[0045] The preparation of high-efficiency catalyst includes the following steps:

[0046] S1 dissolution: The copper slag and zinc tailings were crushed to 200 mesh, immersed in a methanol solution (made by synthesizing carbon dioxide and hydrogen with a catalyst) with a sulfuric acid concentration of 30%, and maintained at a pressure of 0.5 MPa in a closed reactor (the pressure increase raises the boiling point of methanol to above 80°C, ensuring that methanol remains liquid at 70-80°C, while promoting the leaching of copper and zinc. The polarity of methanol can promote the uniform dispersion of metal ions). The mixture was kept at 80°C for 2 hours to leach the copper and zinc. The mixed metal solution and the filter residue with the leached metal were obtained by filtration.

[0047] The filter residue is added to the mixed material at 5% of the mass of the calcium raw material to adjust the strength;

[0048] S2 impurity removal: oxygen is introduced into the mixed metal solution and reacted for 40 minutes. Oxidized to , adjust the solution pH to 4.2, by Form precipitation, control the stirring speed to 200r / min to promote floc growth, and remove the precipitate by centrifugation to obtain a copper-zinc mixed solution;

[0049] S3 crystallization: add 2.0 mol / L sodium carbonate solution preheated to 60℃ to the copper-zinc mixture at a rate of 10 drops / min, adjust the solution pH to 10, and Basic carbonate was generated simultaneously, and the stirring speed was controlled at 400 r / min to avoid local oversaturation that would lead to uneven particle size. At the same time, citric acid, a complexing agent, was added at a concentration of 2% by mass of the copper-zinc mixture to inhibit excessive grain growth and agglomeration through coordination. The mixture was aged for 60 min to promote directional growth of the crystal nuclei to obtain a Cu-Zn precursor.

[0050] S4 washing and drying: After the aged precipitate is centrifuged (8000r / min, 10min), it is washed three times with 60℃ deionized water (the volume of each washing liquid is 3 times the volume of the precipitate) to remove the residual and ions, add anhydrous ethanol with a mass of 1 / 10 of deionized water during the final washing to replace the surface moisture of the particles and reduce hydrogen bond agglomeration during the drying process; dry at 60°C;

[0051] S5 Support Activation: The boron nitride nanosheets were placed in a 0.3 mol / L sodium hydroxide solution and ultrasonically treated at 50°C for 2 h to remove surface impurities and oxides. The surface was then washed with deionized water several times until neutral, and vacuum dried at 150°C to obtain activated boron nitride nanosheets.

[0052] S6 Precursor-Carrier Composite: 3% by mass of carboxymethyl cellulose was added to the Cu-Zn precursor as a binder and stirred to form a paste with a solid content of 75% and good plasticity. The paste was spray-dried at an inlet air temperature of 200°C and an outlet air temperature of 100°C to form spherical particles with a particle size of 100 μm. The precursor was evenly loaded on the carrier surface. The mass ratio of the activated boron nitride nanosheet carrier to the Cu-Zn precursor was 4:1.

[0053] S7 crystal shape control: The spherical particles were placed in a high-temperature tube furnace and heated from room temperature to 350°C at a rate of 4°C / min. The temperature was maintained in an argon and hydrogen mixed atmosphere (hydrogen content 8%) for 1.5 hours to initially remove organic impurities. The temperature was then further increased to 600°C at a rate of 3°C / min and calcined for 50 minutes to convert the basic carbonate into a CuO-ZnO composite oxide.

[0054] S8 reduction: Place the CuO-ZnO composite oxide in an atomic layer deposition apparatus, first introduce nitrogen purge for 30 minutes to remove air, then introduce diethylzinc, an organic precursor of zinc, and hydrogen in sequence, perform atomic layer deposition at 130°C, deposit a zinc atomic layer on the surface of the CuO-ZnO composite oxide, and then switch to a methanol-hydrogen mixture ( The volume fraction was 18%), and the mixture was kept at 280°C for 50 min. At the same time, the atomic layer deposition of zinc atoms was used to induce the directional growth and dispersion of copper atoms, initially reducing part of CuO and forming Cu / ZnO active centers on the CuO-ZnO composite oxide.

[0055] S9 Carbonization: When the reactor temperature drops to 170°C, acetylene gas is introduced at a flow rate of 50 mL / min. The reaction is carried out for 20 minutes. Acetylene is pyrolyzed and carbonized on the surface of the CuO-ZnO composite oxide to form a carbon film, resulting in a highly efficient catalyst. This carbon film not only further stabilizes the Cu / ZnO active centers and inhibits the sintering and agglomeration of metallic Cu grains, but also regulates the electron cloud density on the catalyst surface, enhancing the adsorption and activation of methanol molecules.

[0056] The hydrogen is produced by electrolysis of alkaline water. The electrolyte is a potassium hydroxide solution with a mass fraction of 30%. The operating temperature of the electrolytic cell is maintained at 80°C and the voltage is 2.2V. The produced hydrogen is compressed to 30MPa by a multi-stage compressor and stored in a high-pressure hydrogen storage tank. It is then transported to the calcining kiln through a pipeline. During the transportation process, the pressure is controlled at 2.0MPa.

[0057] Example 2: This example provides a method for producing ferroaluminate cement using hydrogen energy, comprising the following steps: mixing a calcium raw material, an aluminum raw material, an iron raw material, and a sulfur raw material in a mass ratio of 5:2:3:1, ball milling to obtain raw meal powder, calcining the raw meal powder to obtain clinker, and grinding the clinker, a mixed material (slag and fly ash in a mass ratio of 6:4), and gypsum in a mass ratio of 70:25:10 to obtain ferroaluminate cement;

[0058] Among them, after the raw material is fed into the hydrogen sintering furnace, hydrogen and natural gas are mixed in a volume ratio of 1:0.4-0.6 and then calcined in a gradient manner;

[0059] Stage 1: When the volume ratio of hydrogen to natural gas is 1:0.6, the calcination temperature is 1250°C and the time is 40 min;

[0060] Stage 2: When the volume ratio of hydrogen to natural gas is 1:0.5, the calcination temperature is 1280°C and the time is 40 minutes;

[0061] Stage 3: When the volume ratio of hydrogen to natural gas is 1:0.4, the calcination temperature is 1320°C and the time is 40 min;

[0062] Carbon dioxide recovery: An efficient carbon dioxide absorption tower is installed at the exhaust gas outlet of the sintering furnace. Ethanolamine solution is used as the absorbent. The temperature of the absorption tower is controlled at 40°C. The saturated ethanolamine solution is desorbed into high-purity carbon dioxide through a desorption tower at 100°C and 0.1MPa.

[0063] Carbon dioxide and hydrogen were introduced into a fixed bed reactor equipped with a high-efficiency catalyst at a molar ratio of 1:3.5. The reaction temperature was controlled at 200°C, the pressure was 1 MPa, and the gas space velocity was 1000 At the same time, the methanol produced can be used in the preparation of high-efficiency catalysts;

[0064] The preparation of high-efficiency catalyst includes the following steps:

[0065] S1 dissolution: The copper slag and zinc tailings were crushed to 100 mesh, immersed in a methanol solution (made by synthesizing carbon dioxide and hydrogen with a catalyst) with a sulfuric acid concentration of 20%, and maintained at a pressure of 0.2 MPa in a closed reactor (the pressure increase raises the boiling point of methanol to above 80°C, ensuring that methanol remains liquid at 70-80°C, while promoting the leaching of copper and zinc. The polarity of methanol can promote the uniform dispersion of metal ions). The mixture was kept at 70°C for 1 hour to leach the copper and zinc. The mixed metal solution and the filter residue with the leached metal were filtered out;

[0066] The filter residue is added to the mixed material at 3% of the mass of the calcium raw material to adjust the strength;

[0067] S2 impurity removal: introduce oxygen into the mixed metal solution and react for 30 minutes. Oxidized to , adjust the solution pH to 3.8, by Form precipitation, control the stirring speed to 100r / min to promote floc growth, and remove the precipitate by centrifugation to obtain a copper-zinc mixed solution;

[0068] S3 crystallization: add 1.5 mol / L sodium carbonate solution preheated to 50°C to the copper-zinc mixture at a rate of 6 drops / min, adjust the solution pH to 8, and Basic carbonate was generated simultaneously, and the stirring speed was controlled at 200 r / min to avoid local oversaturation leading to uneven particle size. At the same time, citric acid, a complexing agent, was added at a concentration of 0.5% by mass of the copper-zinc mixture to inhibit excessive grain growth and agglomeration through coordination. The mixture was aged for 40 min to promote directional growth of the crystal nuclei to obtain a Cu-Zn precursor.

[0069] S4 washing and drying: After the aged precipitate is centrifuged (8000r / min, 10min), it is washed twice with 50℃ deionized water (the volume of each washing liquid is 3 times the volume of the precipitate) to remove the residual and ions, add anhydrous ethanol with a mass of 1 / 10 of deionized water during the final washing to replace the surface moisture of the particles and reduce hydrogen bond agglomeration during the drying process; dry at 50°C;

[0070] S5 Support Activation: Place the boron nitride nanosheets in a 0.2 mol / L sodium hydroxide solution and ultrasonically treat at 40°C for 1 hour to remove surface impurities and oxides. Then, wash with deionized water several times until neutral, and vacuum dry at 100°C to obtain activated boron nitride nanosheets.

[0071] S6 Precursor-Carrier Composite: Add 2% by mass of carboxymethyl cellulose as a binder to the Cu-Zn precursor and stir evenly to form a paste with good plasticity and a solid content of 65%. Use a spray drying method to prepare spherical particles with a particle size of 50 μm at an inlet air temperature of 180°C and an outlet air temperature of 90°C, so that the precursor is evenly loaded on the carrier surface. The mass ratio of the activated boron nitride nanosheet carrier to the Cu-Zn precursor is 2:1.

[0072] S7 crystal shape control: The spherical particles were placed in a high-temperature tube furnace and heated from room temperature to 300°C at a rate of 3°C / min. The temperature was maintained in an argon and hydrogen mixed atmosphere (hydrogen content 5%) for 1 hour to initially remove organic impurities. The temperature was then further increased to 550°C at a rate of 2°C / min and calcined for 30 minutes to convert the basic carbonate into a CuO-ZnO composite oxide.

[0073] S8 reduction: Place the CuO-ZnO composite oxide in an atomic layer deposition apparatus, first introduce nitrogen purge for 30 minutes to remove air, then introduce diethylzinc, an organic precursor of zinc, and hydrogen in sequence, perform atomic layer deposition at 120°C, deposit a layer of zinc atoms on the surface of the CuO-ZnO composite oxide, and then switch to a methanol-hydrogen mixture ( volume fraction of 12%), and then kept at 250°C for 30 min. At the same time, the atomic layer deposition of zinc atoms was used to induce the directional growth and dispersion of copper atoms, initially reducing part of CuO and forming Cu / ZnO active centers on the CuO-ZnO composite oxide.

[0074] S9 Carbonization: When the reactor temperature drops to 150°C, acetylene gas is introduced at a flow rate of 30 mL / min. The reaction is carried out for 15 minutes. Acetylene is pyrolyzed and carbonized on the surface of the CuO-ZnO composite oxide to form a carbon film, resulting in a highly efficient catalyst. This carbon film not only further stabilizes the Cu / ZnO active centers and inhibits the sintering and agglomeration of metallic Cu grains, but also regulates the electron cloud density on the catalyst surface, enhancing the adsorption and activation of methanol molecules.

[0075] The hydrogen is produced by electrolysis of alkaline water. The electrolyte is a potassium hydroxide solution with a mass fraction of 20%. The operating temperature of the electrolytic cell is maintained at 70°C and the voltage is 1.8V. The produced hydrogen is compressed to 20MPa by a multi-stage compressor and stored in a high-pressure hydrogen storage tank. It is then transported to the calcining kiln through a pipeline. During the transportation process, the pressure is controlled at 1.5MPa.

[0076] Example 3: This example provides a method for producing ferroaluminate cement using hydrogen energy, comprising the following steps: mixing a calcium raw material, an aluminum raw material, an iron raw material, and a sulfur raw material in a mass ratio of 5:2:3:1, ball milling to obtain raw meal powder, calcining the raw meal powder to obtain clinker, and grinding the clinker, a mixed material (slag and fly ash in a mass ratio of 6:4), and gypsum in a mass ratio of 70:25:10 to obtain ferroaluminate cement;

[0077] Among them, after the raw material is fed into the hydrogen sintering furnace, hydrogen and natural gas are mixed in a volume ratio of 1:0.4-0.6 and then calcined in a gradient manner;

[0078] Stage 1: When the volume ratio of hydrogen to natural gas is 1:0.6, the calcination temperature is 1260°C and the time is 42 min;

[0079] Stage 2: When the volume ratio of hydrogen to natural gas is 1:0.5, the calcination temperature is 1310°C and the time is 48 minutes;

[0080] Stage 3: When the volume ratio of hydrogen to natural gas is 1:0.4, the calcination temperature is 1340°C and the time is 55 min;

[0081] Carbon dioxide recovery: An efficient carbon dioxide absorption tower is installed at the exhaust gas outlet of the sintering furnace. Ethanolamine solution is used as the absorbent. The temperature of the absorption tower is controlled at 48°C. The saturated ethanolamine solution is desorbed into high-purity carbon dioxide through a desorption tower at 106°C and 0.15MPa.

[0082] Carbon dioxide and hydrogen were introduced into a fixed bed reactor equipped with a high-efficiency catalyst at a molar ratio of 1:3.8. The reaction temperature was controlled at 230°C, the pressure was 2 MPa, and the gas space velocity was 1200 At the same time, the methanol produced can be used in the preparation of high-efficiency catalysts;

[0083] The preparation of high-efficiency catalyst includes the following steps:

[0084] S1 dissolution: The copper slag and zinc tailings were crushed to 180 mesh, immersed in a methanol solution (made by synthesizing carbon dioxide and hydrogen with a catalyst) with a sulfuric acid concentration of 22%, and maintained at a pressure of 0.4 MPa in a closed reactor (the pressure increase raises the boiling point of methanol to above 80°C, ensuring that methanol remains liquid at 70-80°C, while promoting the leaching of copper and zinc. The polarity of methanol can promote the uniform dispersion of metal ions). The mixture was kept at 72°C for 1.2 hours to leach the copper and zinc. The mixed metal solution and the filter residue with the leached metals were filtered out;

[0085] The filter residue is added to the mixed material at 4% of the mass of the calcium raw material to adjust the strength;

[0086] S2 impurity removal: oxygen is introduced into the mixed metal solution and reacted for 34 minutes. Oxidized to , adjust the solution pH to 4.1, by Form precipitation, control the stirring speed to 160r / min to promote floc growth, and remove the precipitate by centrifugation to obtain a copper-zinc mixed solution;

[0087] S3 crystallization: add 1.7 mol / L sodium carbonate solution preheated to 54°C to the copper-zinc mixture at a rate of 8 drops / min, adjust the solution pH to 9, and Basic carbonate was generated simultaneously, and the stirring speed was controlled at 300 r / min to avoid local oversaturation and uneven particle size. At the same time, citric acid, a complexing agent, was added at a concentration of 1% by mass of the copper-zinc mixture to inhibit excessive grain growth and agglomeration through coordination. The mixture was aged for 52 minutes to promote directional growth of the crystal nuclei and obtain a Cu-Zn precursor.

[0088] S4 washing and drying: After the aged precipitate is centrifuged (8000r / min, 10min), it is washed three times with 55℃ deionized water (the volume of each washing liquid is 3 times the volume of the precipitate) to remove the residual and ions, add anhydrous ethanol with a mass of 1 / 10 of deionized water during the final wash to replace the surface moisture of the particles and reduce hydrogen bond aggregation during the drying process; dry at 56°C;

[0089] S5 Support Activation: Place the boron nitride nanosheets in a 0.22 mol / L sodium hydroxide solution and ultrasonically treat at 47°C for 1 hour to remove surface impurities and oxides. Then, wash with deionized water several times until neutral, and vacuum dry at 120°C to obtain activated boron nitride nanosheets.

[0090] S6 Precursor-Carrier Composite: 2.5% by mass of carboxymethyl cellulose was added to the Cu-Zn precursor as a binder and stirred to form a paste with a solid content of 72% and good plasticity. The paste was spray-dried at an inlet air temperature of 190°C and an outlet air temperature of 98°C to form spherical particles with a particle size of 80 μm. The precursor was evenly loaded on the carrier surface. The mass ratio of the activated boron nitride nanosheet carrier to the Cu-Zn precursor was 3:1.

[0091] S7 crystal shape control: The spherical particles were placed in a high-temperature tube furnace and heated from room temperature to 330°C at a rate of 3°C / min. The temperature was maintained in an argon and hydrogen mixture (7% hydrogen content) for 1.5 hours to initially remove organic impurities. The temperature was then increased to 580°C at a rate of 2°C / min and calcined for 40 minutes to convert the basic carbonate into a CuO-ZnO composite oxide.

[0092] S8 reduction: Place the CuO-ZnO composite oxide in an atomic layer deposition apparatus, first introduce nitrogen purge for 30 minutes to remove air, then introduce diethylzinc, an organic precursor of zinc, and hydrogen in sequence, perform atomic layer deposition at 128°C, deposit a zinc atomic layer on the surface of the CuO-ZnO composite oxide, and then switch to a methanol-hydrogen mixture ( The volume fraction was 16%), and the mixture was kept at 270°C for 40 minutes. At the same time, the atomic layer deposition of zinc atoms was used to induce the directional growth and dispersion of copper atoms, initially reducing part of CuO and forming Cu / ZnO active centers on the CuO-ZnO composite oxide.

[0093] S9 Carbonization: When the reactor temperature drops to 160°C, acetylene gas is introduced at a flow rate of 40 mL / min. The reaction is carried out for 18 minutes. Acetylene is pyrolyzed and carbonized on the surface of the CuO-ZnO composite oxide to form a carbon film, resulting in a highly efficient catalyst. This carbon film not only further stabilizes the Cu / ZnO active centers and inhibits the sintering and agglomeration of metallic Cu grains, but also regulates the electron cloud density on the catalyst surface, enhancing the adsorption and activation of methanol molecules.

[0094] The hydrogen is produced by electrolysis of alkaline water. The electrolyte is a potassium hydroxide solution with a mass fraction of 25%. The operating temperature of the electrolytic cell is maintained at 77°C and the voltage is 2.1V. The produced hydrogen is compressed to 24MPa by a multi-stage compressor and stored in a high-pressure hydrogen storage tank. It is then transported to the calcining kiln through a pipeline. During the transportation process, the pressure is controlled at 1.8MPa.

[0095] Comparative Example 1: This comparative example differs from Example 3 in that filter residue is not added to the mixed material.

[0096] Comparative Example 2: The difference between this comparative example and Example 3 is that, when preparing the high-efficiency catalyst, an aqueous solution with a sulfuric acid concentration of 20-30% is used for dissolving S1, rather than a methanol solution.

[0097] Comparative Example 3: This comparative example differs from Example 3 in that the S8 reduction step is not performed when preparing the high-efficiency catalyst.

[0098] Comparative Example 4: This comparative example differs from Example 3 in that the S9 carbonization step is not performed when preparing the high-efficiency catalyst.

[0099] Comparative Example 5: The difference between this comparative example and Example 3 is that, when preparing the high-efficiency catalyst, 1. an aqueous solution with a sulfuric acid concentration of 20-30% is used for dissolving S1 instead of a methanol solution; 2. the S8 reduction step is not performed; and the S9 carbonization step is not performed.

[0100] Comparative example: This comparative example uses a CuZnAl catalyst doped with 5% Ce.

[0101] The preparation method of the above catalyst is selected from Li Wenxuan, Wang Bin, Li Jing, etc. Ce doped CuZnAl catalyst Influence of catalytic performance on hydrogenation to methanol[J / OL]. Low Carbon Chemistry and Chemical Engineering, 1-9[2025-04-25]. http: / / kns.cnki.net / kcms / detail / 51.1807.tq.20250416.1602.002.html.

[0102] Experimental Example 1: The mechanical properties of cement were tested on Examples 1-3 and Comparative Example 1 according to the "Test Method for Cement Mortar Strength (ISO Method)" (GB / T 17671-2021);

[0103] Specimen Preparation: Cement, Chinese ISO standard sand, and water were mixed according to the prescribed proportions and methods to form a plastic cement mortar. The mass ratio of cement to standard sand was 1:3, and the water-cement ratio was 0.5. The mixed mortar was loaded into a 40mm x 40mm x 160mm triple test mold in two layers. Each layer was compacted using a vibrating table, scraped flat, and then placed in a standard curing box for curing.

[0104] Curing conditions: The specimens were cured in water at (20±1)℃ for up to 28 days.

[0105] Flexural strength test: Use a flexural testing machine to take out the specimen that has been cured to the specified age, wipe off the moisture and sand on the surface, place it on the two supporting cylinders of the flexural testing machine, and apply load evenly at a specified rate until the specimen breaks. Record the failure load and flexural strength.

[0106] Compressive strength test: After the flexural test, the two half prisms are placed on a compression testing machine for compression testing. The load is applied uniformly at a specified rate until the specimen is destroyed. The failure load is recorded and the compressive strength is calculated.

[0107] The results are shown in Table 1:

[0108] Table 1

[0109]

[0110] As can be seen from the above table, the present invention achieves a slight increase in cement strength by adding copper slag and zinc tailings slag from which metals have been leached into the clinker.

[0111] Experimental Example 2: The catalytic performance of the catalysts prepared in Examples 1-3, Comparative Examples 2-5 and the Control Example was tested;

[0112] Carbon dioxide conversion rate: The concentration change of carbon dioxide before and after the reaction was analyzed by gas chromatography, and the carbon dioxide conversion rate was calculated using the following formula:

[0113]

[0114] The higher the conversion rate, the stronger the catalyst's ability to activate and convert carbon dioxide.

[0115] Methanol selectivity: The methanol content in the reaction product and the content of other by-products (such as carbon monoxide and methane) are analyzed by gas chromatography to calculate the methanol selectivity. The formula is:

[0116]

[0117] High methanol selectivity means that the catalyst can more effectively promote the target reaction to produce methanol and reduce the occurrence of side reactions.

[0118] Space-time yield of methanol:

[0119] Refers to the mass of methanol produced per unit time and per unit mass (or volume) of catalyst, usually expressed in gMeOH This index comprehensively considers the activity and reaction rate of the catalyst and can more comprehensively reflect the performance of the catalyst in actual production:

[0120]

[0121] In addition, it is necessary to convert the space-time yield in the control example to units. The prepared catalyst mass concentration c = 0.1 g / mL, 1 mg / (mL·h) = 0.01 g MeOH .

[0122] The results are shown in Table 2:

[0123] Table 2

[0124]

[0125] As can be seen from the above table, the present invention replaces the metals in the water-soluble copper slag and zinc tailings slag with methanol, thereby effectively improving the selectivity of methanol; forms Cu / ZnO active centers on the CuO-ZnO composite oxide by diethyl zinc, thereby improving the conversion rate of carbon dioxide; forms a carbon film by pyrolysis and carbonization of acetylene on the surface of the CuO-ZnO composite oxide, thereby significantly improving the space-time yield of methanol; and the combination of the above three technical solutions produces a synergistic effect in improving the selectivity of methanol, improving the conversion rate of carbon dioxide, and improving the space-time yield of methanol.

[0126] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A method for producing ferroaluminate cement using hydrogen energy, comprising the following steps: The raw meal powder is calcined to obtain clinker, and the clinker, mixed materials and gypsum powder are ground to obtain ferroaluminate cement; wherein the raw meal calcination fuel is a mixture of hydrogen and natural gas; The recovered carbon dioxide and hydrogen are synthesized into methanol through a high-efficiency catalyst, and the obtained methanol is used in the preparation of the high-efficiency catalyst; The preparation of high-efficiency catalyst includes the following steps: S1 dissolution: crush the copper slag and zinc tailings, immerse them in sulfuric acid methanol solution, and filter to obtain a mixed metal solution and filter residue; The filter residue is added to the mixed material at 3-5% of the mass of the calcium raw material; S2 impurity removal; S3 crystallization; S4 washing and drying; S5 vector activation; S6 Precursor-Carrier Composite: The precursor is evenly loaded on the carrier surface to form spherical particles; S7 crystal shape control: heating the spherical particles to remove impurities; continuing to heat to obtain CuO-ZnO composite oxide; S8 reduction: Diethylzinc and hydrogen are introduced into the CuO-ZnO composite oxide, and then the gas is switched to a methanol-hydrogen mixture to form Cu / ZnO active centers; S9 Carbonization: Acetylene gas is introduced to pyrolyze and carbonize the surface of the CuO-ZnO composite oxide to form a carbon film to obtain a high-efficiency catalyst.

2. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: After the raw material is fed into the hydrogen sintering furnace, hydrogen and natural gas are mixed in a volume ratio of 1:0.4-0.6 and then calcined in a gradient manner; Stage 1: calcination temperature 1250-1280°C, time 40-60 min; Stage 2: calcination temperature 1280-1320℃, time 40-60min; Stage three: calcination temperature 1320-1350°C, time 40-60 min.

3. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: The specific method for recovering carbon dioxide is as follows: an efficient carbon dioxide absorption tower is installed at the exhaust gas outlet of the hydrogen sintering furnace, ethanolamine solution is used as the absorbent, the temperature of the absorption tower is controlled at 40-50°C, and the saturated ethanolamine solution is desorbed into high-purity carbon dioxide through a desorption tower at 100-120°C and 0.1-0.2MPa.

4. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S1 dissolution: Crush the copper slag and zinc tailings to 100-200 mesh, immerse them in a methanol solution with a sulfuric acid concentration of 20-30%, maintain a pressure of 0.2-0.5MPa in a closed reactor, and keep it at 70-80℃ for 1-2h to leach out the copper and zinc. Filter to obtain a mixed metal solution and a filter residue with the leached metal.

5. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S3 is specifically: add 1.5-2.0 mol / L sodium carbonate solution preheated to 50-60°C to the copper-zinc mixture at a rate of 6-10 drops / min, and adjust the solution pH to 8-10. and Basic carbonate is generated synchronously, and the stirring speed is controlled at 200-400 r / min to avoid local oversaturation resulting in uneven particle size. At the same time, citric acid, a complexing agent, is added at a concentration of 0.5-2% by mass of the copper-zinc mixture to inhibit excessive grain growth and agglomeration through coordination. The mixture is aged for 40-60 minutes to promote the directional growth of the crystal nucleus to obtain a Cu-Zn precursor.

6. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S5 is specifically as follows: placing the boron nitride nanosheets in a sodium hydroxide solution with a concentration of 0.2-0.3 mol / L, ultrasonically treating at 40-50°C for 1-2 hours to remove surface impurities and oxides, washing with deionized water multiple times until neutral, and vacuum drying at 100-150°C to obtain activated boron nitride nanosheets.

7. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S6 is specifically as follows: add 2-3% by mass of carboxymethyl cellulose as a binder to the Cu-Zn precursor, stir evenly to form a paste with good plasticity and a solid content of 65-75%, and use a spray drying method to make the paste into spherical particles with a particle size of 50-100μm under the conditions of an inlet air temperature of 180-200℃ and an outlet air temperature of 90-100℃, so that the precursor is evenly loaded on the surface of the carrier, and the mass ratio of the activated boron nitride nanosheet carrier and the Cu-Zn precursor is 2-4:

1.

8. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S7 is specifically as follows: placing the spherical particles in a high-temperature tube furnace, heating the temperature from room temperature to 300-350°C at a heating rate of 3-4°C / min, and keeping the temperature in a mixed atmosphere of argon and hydrogen for 1-1.5 hours to preliminarily remove organic impurities; continuing to heat the temperature to 550-600°C at a heating rate of 2-3°C / min, calcining for 30-50 minutes to promote the conversion of basic carbonate into CuO-ZnO composite oxide.

9. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S8 is specifically as follows: placing the CuO-ZnO composite oxide into an atomic layer deposition device, introducing diethylzinc and hydrogen, an organic precursor of zinc, in sequence, performing atomic layer deposition at 120-130°C, depositing a layer of zinc atoms on the surface of the CuO-ZnO composite oxide, switching to a methanol-hydrogen mixed gas, and keeping warm at 250-280°C for 30-50 minutes. The atomically deposited zinc atomic layer is used to induce the directional growth and dispersion of copper atoms, preliminarily reducing part of the CuO, and forming a Cu / ZnO active center on the CuO-ZnO composite oxide.

10. The method for producing ferroaluminate cement using hydrogen energy according to claim 1, characterized in that: S9 is specifically as follows: when the temperature of the reactor drops to 150-170°C, acetylene gas is introduced with a flow rate controlled at 30-50 mL / min, and the reaction is carried out for 15-20 minutes. Acetylene is pyrolyzed and carbonized on the surface of the CuO-ZnO composite oxide to form a carbon film, thereby obtaining a high-efficiency catalyst.

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