Blast furnace coal injection composite combustion improver and production process thereof

Abstract

The present application relates to the technical field of blast furnace ironmaking, in particular to a blast furnace coal injection composite combustion improver and a production process thereof; the raw material composition of the composite combustion improver comprises cerium ammonium nitrate, copper nitrate, catalytic oxygen-increasing composite component, manganese dioxide, blast furnace dust, quicklime and binder, wherein the catalytic oxygen-increasing composite component is formed by loading calcium peroxide on a calcium-manganese composite carrier to form a supported oxygen-increasing matrix, and then impregnated with cerium and copper catalytic active components; the production process of the composite combustion improver comprises mixing and grinding the raw materials to obtain mixed powder, then granulating with water and stepwise drying the wet granules to obtain the composite combustion improver; the present application effectively improves the coal powder combustion performance through the coupling of catalysis and oxygen-increasing functions, and realizes the resource utilization of blast furnace dust; the composite combustion improver can lower the coal powder ignition point, improve the combustion rate and reduce the blast furnace coke ratio.

Description

Technical Field

[0001] This invention relates to the field of blast furnace ironmaking technology, specifically to a composite combustion aid for blast furnace pulverized coal injection and its production process. Background Technology

[0002] Pulverized coal injection (PCI) technology is one of the core methods for reducing coke consumption and costs in modern blast furnace ironmaking. By injecting pulverized coal into the blast furnace tuyeres to replace part of the metallurgical coke, the production cost of molten iron can be effectively reduced. The combustion efficiency of pulverized coal in the tuyeres directly determines the pulverized coal replacement ratio. However, pulverized coal suffers from problems such as high ignition temperature and insufficient burnout time, which restricts further increases in the amount of pulverized coal injected. To improve the combustion efficiency of pulverized coal, various combustion aids are usually added to the injected pulverized coal to improve its ignition characteristics and combustion process through catalytic combustion or oxygenation.

[0003] Chinese patent application CN1793386A discloses a blast furnace injection catalytic enhancer and its production process. This blast furnace injection catalytic enhancer is formulated by weight percentage of 10-30% catalytic cracking combustion aid, 5-30% oxygenator, 10-30% solid flux, 20-40% catalyst, and 10-30% enhancer. It accelerates pulverized coal combustion through catalytic cracking and enhanced combustion, effectively increasing the pulverized coal injection ratio and significantly reducing the coke ratio, achieving good coke saving and cost reduction effects. However, this type of combustion aid, composed of simple physical mixtures of multiple components, still suffers from insufficient synergy between the catalytic and oxygenating components in practical applications. The timing of active oxygen release is poorly matched with the pulverized coal combustion process, resulting in low oxygen utilization. Furthermore, the resource utilization of iron- and carbon-containing solid wastes such as blast furnace dust in the field of combustion aids remains relatively limited.

[0004] Therefore, developing a composite combustion aid for blast furnace pulverized coal injection with good synergistic catalytic and oxygenation functions, high utilization rate of active components, and the ability to realize the resource utilization of solid waste is of positive practical significance for improving the combustion effect of pulverized coal and reducing the coke ratio of blast furnace. Summary of the Invention

[0005] (a) Technical problems to be solved The purpose of this invention is to provide a composite combustion aid for blast furnace pulverized coal injection and its production process, so as to solve the problem of insufficient synergistic effect of existing combustion aids in catalysis and oxygenation, realize the resource utilization of blast furnace dust, and achieve the effects of reducing the ignition point of pulverized coal, increasing the combustion rate and reducing the coke ratio.

[0006] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: A production process for a composite combustion aid for blast furnace pulverized coal injection, comprising the following steps by weight: S1. Mix 8-15 parts of cerium ammonium nitrate, 5-10 parts of copper nitrate, 25-35 parts of catalytic oxygenation composite component, 10-20 parts of manganese dioxide, 15-25 parts of blast furnace dust, 5-12 parts of quicklime, and 2-5 parts of binder at a ball-to-material mass ratio of 5-10:1 and grind for 30-90 minutes. The grinding speed is 200-400 r / min, the grinding media is zirconia balls or steel balls, and the filling rate is 35-50%. During the grinding process, the material temperature is controlled not to exceed 40℃ to obtain mixed powder. S2. Mix the powder with water at a weight ratio of 100:(5-10) and granulate. The granulation speed is 30-80 r / min. The water is added in two stages, first slowly and then quickly. 20-30% of the total water is added in the first 1 / 3 of the time period, and the remaining water is added in the last 2 / 3 of the time period. The granulation time is 10-30 min to obtain wet granules. S3. The wet material particles are first dried at 35-50℃ for 30-60 minutes, during which the hot air velocity is 0.5-1.5 m / s and the material is turned over once every 15-30 minutes. Then, they are dried at 50-80℃ for 20-40 minutes, during which the hot air velocity is 1.0-2.5 m / s, thus obtaining the blast furnace pulverized coal composite combustion aid.

[0007] Furthermore, the preparation method of the catalytic oxygenation composite component includes the following steps: immersing the supported oxygenation body in an aqueous solution containing cerium ammonium nitrate and copper nitrate, wherein the total concentration of cerium ammonium nitrate and copper nitrate in the aqueous solution is 10-25 wt%, stirring and adsorbing at 50-70℃ and a rotation speed of 80-150 r / min for 2-4 h, filtering, and drying at 60-90℃, wherein the material is spread to a thickness of 1-3 cm during the drying process, to obtain the catalytic oxygenation composite component; Furthermore, the weight ratio of the supported oxygen-enhancing agent, cerium ammonium nitrate, and copper nitrate is 100:(15-30):(10-20).

[0008] Furthermore, the preparation method of the supported oxygen-reinforcing gas includes the following steps: Step 1: Mix manganese dioxide and quicklime at a molar ratio of 1:(0.5-1.5), add deionized water to prepare a slurry with a solid content of 15-25%, stir and disperse at 200-400 r / min for 30-60 min, and perform hydrothermal reaction at 80-95℃ for 3-6 h. During the hydrothermal reaction, continue stirring at a stirring speed of 100-200 r / min. Filter, wash, and dry at 80-100℃ for 6-12 h to obtain a calcium-manganese composite carrier. Step 2: Mix the calcium-manganese composite carrier with calcium peroxide at a weight ratio of 1:(0.3-0.8), add water accounting for 3-8% of the total weight of the mixture, and grind under sealed conditions at a speed of 30-60 r / min for 2-4 hours. The grinding media is zirconia balls with a ball-to-material mass ratio of 3-6:1. Vacuum dry at a vacuum degree of -0.06 to -0.09 MPa to obtain the supported oxygen-enriched body.

[0009] Furthermore, in step two, the drying process employs a gradient heating method, first drying at 60-65℃ for 1-2 hours, and then heating to 75-80℃ for another 1-2 hours.

[0010] Furthermore, in step S1, the binder can be any one of pregelatinized starch, sodium carboxymethyl cellulose, or sodium silicate.

[0011] Furthermore, in step S1, the fixed carbon content of the blast furnace dust is 15-35%, the total iron content is 20-40%, and the particle size distribution D90 of the blast furnace dust is less than 150μm.

[0012] Furthermore, the grinding process in step S1 is carried out intermittently, with a 3-5 minute pause after every 10-15 minutes of operation.

[0013] Furthermore, in step S2, water is added by atomizing and spraying during mixing and granulation. The pressure of the atomizing nozzle is 0.2-0.6 MPa, and the diameter of the atomized droplets is 50-200 μm.

[0014] Furthermore, in step S2, the particle size of the wet material is 2-8 mm.

[0015] This invention also provides a composite combustion aid for blast furnace pulverized coal injection, which is prepared by the production process described above.

[0016] (iii) Beneficial technical effects Compared with the prior art, the beneficial effects of the present invention are: (1) The catalytic oxygen-enriching composite component of the present invention is first synthesized by hydrothermal reaction of manganese dioxide and quicklime to form a calcium-manganese composite support, and then the calcium peroxide is ground and loaded onto the support to form a supported oxygen-enriching body. Finally, cerium and copper catalytic active components are introduced by impregnation. During the hydrothermal reaction, the calcium hydroxide generated by the hydration of quicklime reacts with manganese dioxide to form a calcium-manganese composite oxide with a porous structure. This support provides abundant anchoring sites and structural framework for the subsequent loading of functional components, so that the active components can be uniformly dispersed and stably attached. The grinding and loading process allows the calcium peroxide particles to be coated and embedded by the support. At high temperature, this coating structure can delay the release rate of active oxygen, making the oxygen supply rhythm more matched with the coal powder combustion process, reducing the ineffective loss of active oxygen, and improving oxygen utilization. Furthermore, the cerium and copper ions introduced by impregnation are uniformly distributed on the surface and inside the pores of the support, and together with the manganese element in the support, they form a synergistic catalytic system with multiple active centers of cerium, copper and manganese. The catalytic sites and oxygenation sites are closely adjacent at the microscale, and once the active oxygen is released, it can be rapidly activated by the nearby catalytic centers, which significantly enhances the ignition sensitivity of pulverized coal and the combustion reaction rate.

[0017] (2) The unburned carbon in the blast furnace dust of the present invention can continue to participate in the reaction and provide heat during the combustion process. The iron oxide contained therein has a catalytic and auxiliary effect on the gasification reaction of carbon, and together with quicklime, it forms a sulfur fixation system, which can reduce the emission of sulfur-containing gases and realize the unity of resource utilization of solid waste and clean combustion.

[0018] (3) The present invention first removes the free water in the wet material particles at low temperature and then removes the residual moisture by raising the temperature, which effectively avoids the decomposition and deactivation of the heat-sensitive catalytic components and oxygenation components during the drying process. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1 A production process for a composite combustion aid for blast furnace pulverized coal injection includes the following steps: S1. By weight, 8 parts of cerium ammonium nitrate, 5 parts of copper nitrate, 25 parts of catalytic oxygenation composite component, 10 parts of manganese dioxide, 15 parts of blast furnace dust, 5 parts of quicklime, and 2 parts of binder are mixed and ground at a ball-to-material mass ratio of 5:1 for 30 minutes. The grinding speed is 200 r / min, the grinding media is steel balls, and the filling rate is 35%. The grinding process is carried out intermittently, with a 3-minute pause every 10 minutes. The material temperature is controlled not to exceed 40℃ during the grinding process to obtain a mixed powder. The blast furnace dust has a fixed carbon content of 15%, a total iron content of 20%, and a particle size distribution D90 of 149 μm. The binder is pregelatinized starch. S2. The mixed powder and water are mixed and granulated at a weight ratio of 100:5. The granulation speed is 30 r / min. Water is added by atomization spraying. The pressure of the atomizing nozzle is 0.2 MPa and the diameter of the atomized droplets is 200 μm. The water is added in two stages, first slowly and then quickly. 20% of the total water is added in the first 1 / 3 of the time period, and the remaining water is added in the last 2 / 3 of the time period. The granulation time is 10 min to obtain wet granules with a particle size of 2 mm. S3. The wet material particles are first dried at 35°C for 60 minutes, during which the hot air velocity is 0.5 m / s and the material is turned over once every 15 minutes. Then, they are dried at 50°C for 40 minutes, during which the hot air velocity is 1.0 m / s, thus obtaining the blast furnace pulverized coal composite combustion aid.

[0021] In this embodiment, the catalytic oxygenation composite component is prepared by the following method: a supported oxygenation agent is impregnated in an aqueous solution containing cerium ammonium nitrate and copper nitrate, wherein the total concentration of cerium ammonium nitrate and copper nitrate in the aqueous solution is 10 wt%, and the mixture is stirred and adsorbed at 50°C and a speed of 80 r / min for 4 h. After filtration, the mixture is dried at 60°C, and the material is spread to a thickness of 3 cm during the drying process to obtain the catalytic oxygenation composite component; wherein the weight ratio of the supported oxygenation agent, cerium ammonium nitrate, and copper nitrate is 100:15:10.

[0022] In this embodiment, the supported oxygen-enhancing gas was prepared by the following method: Step 1: Mix manganese dioxide and quicklime at a molar ratio of 1:0.5, add deionized water to prepare a slurry with a solid content of 15%, stir and disperse at 200 r / min for 30 min, and then perform a hydrothermal reaction at 80℃ for 6 h. During the hydrothermal reaction, continue stirring at a stirring speed of 100 r / min. Filter, wash, and dry at 80℃ for 12 h to obtain a calcium-manganese composite carrier. Step 2: Mix the calcium-manganese composite carrier with calcium peroxide at a weight ratio of 1:0.3, add water accounting for 3% of the total weight of the mixture, and grind under sealed conditions at a speed of 30 r / min for 4 hours. The grinding media is zirconia balls with a ball-to-material mass ratio of 3:1. Vacuum drying is performed at a vacuum degree of -0.06 MPa. The drying adopts a gradient heating method, first drying at 60℃ for 2 hours, and then heating to 75℃ for 2 hours to obtain the supported oxygen-enriched body.

[0023] Example 2 A production process for a composite combustion aid for blast furnace pulverized coal injection includes the following steps: S1. By weight, 12 parts of cerium ammonium nitrate, 8 parts of copper nitrate, 30 parts of catalytic oxygenation composite component, 15 parts of manganese dioxide, 20 parts of blast furnace dust, 8 parts of quicklime, and 4 parts of binder are mixed and ground at a ball-to-material mass ratio of 8:1 for 60 minutes. The grinding speed is 300 r / min, the grinding media is zirconia balls, and the filling rate is 42%. The grinding process is carried out intermittently, with a 4-minute pause every 12 minutes. The material temperature is controlled not to exceed 40℃ during the grinding process to obtain a mixed powder. The blast furnace dust has a fixed carbon content of 25%, a total iron content of 30%, and a particle size distribution D90 of 100 μm. The binder is sodium carboxymethyl cellulose. S2. The mixed powder and water are mixed and granulated at a weight ratio of 100:8. The granulation speed is 55 r / min. Water is added by atomization spraying. The pressure of the atomizing nozzle is 0.4 MPa and the diameter of the atomized droplets is 120 μm. The water is added in two stages, first slowly and then quickly. 25% of the total water is added in the first 1 / 3 of the time period, and the remaining water is added in the last 2 / 3 of the time period. The granulation time is 20 min to obtain wet granules with a particle size of 5 mm. S3. The wet material particles are first dried at 42°C for 45 minutes, during which the hot air velocity is 1.0 m / s and the material is turned over once every 22 minutes. Then, they are dried at 65°C for 30 minutes, during which the hot air velocity is 1.8 m / s, thus obtaining the blast furnace pulverized coal composite combustion aid.

[0024] In this embodiment, the catalytic oxygenation composite component is prepared by the following method: a supported oxygenation agent is impregnated in an aqueous solution containing cerium ammonium nitrate and copper nitrate, wherein the total concentration of cerium ammonium nitrate and copper nitrate in the aqueous solution is 18 wt%. The mixture is stirred and adsorbed at 60°C and a speed of 120 r / min for 3 h. After filtration, the mixture is dried at 75°C, and the material is spread to a thickness of 2 cm during the drying process to obtain the catalytic oxygenation composite component. The weight ratio of the supported oxygenation agent, cerium ammonium nitrate, and copper nitrate is 100:22:15.

[0025] In this embodiment, the supported oxygen-enhancing gas was prepared by the following method: Step 1: Mix manganese dioxide and quicklime at a molar ratio of 1:1.0, add deionized water to prepare a slurry with a solid content of 20%, stir and disperse at 300 r / min for 45 min, and hydrothermally react at 88℃ for 4.5 h. During the hydrothermal reaction, stir continuously at a stirring speed of 150 r / min. Filter, wash, and dry at 90℃ for 9 h to obtain a calcium-manganese composite carrier. Step 2: Mix the calcium-manganese composite carrier with calcium peroxide at a weight ratio of 1:0.55, add water accounting for 5% of the total weight of the mixture, and grind under sealed conditions at a speed of 45 r / min for 3 hours. The grinding media is zirconia balls with a ball-to-material mass ratio of 4:1. Vacuum drying is performed at a vacuum degree of -0.08 MPa. The drying adopts a gradient heating method, first drying at 63℃ for 1.5 hours, and then heating to 78℃ for 1.5 hours to obtain the supported oxygen-enriched body.

[0026] Example 3 A production process for a composite combustion aid for blast furnace pulverized coal injection, comprising the following steps by weight: S1. By weight, 15 parts of cerium ammonium nitrate, 10 parts of copper nitrate, 35 parts of catalytic oxygenation composite component, 20 parts of manganese dioxide, 25 parts of blast furnace dust, 12 parts of quicklime, and 5 parts of binder are mixed and ground at a ball-to-material mass ratio of 10:1 for 90 minutes. The grinding speed is 400 r / min, the grinding media is zirconia balls, and the filling rate is 50%. The grinding process is carried out intermittently, with a 5-minute pause every 15 minutes. The material temperature is controlled not to exceed 40℃ during the grinding process to obtain a mixed powder. The blast furnace dust has a fixed carbon content of 35%, a total iron content of 40%, and a particle size distribution D90 of 38 μm. The binder is sodium silicate. S2. The mixed powder and water are mixed and granulated at a weight ratio of 100:10. The granulation speed is 80 r / min. Water is added by atomization spraying. The pressure of the atomizing nozzle is 0.6 MPa and the diameter of the atomized droplets is 50 μm. The water is added in two stages, first slowly and then quickly. 30% of the total water is added in the first 1 / 3 of the time period, and the remaining water is added in the last 2 / 3 of the time period. The granulation time is 30 min to obtain wet granules with a particle size of 8 mm. S3. The wet material particles are first dried at 50°C for 30 minutes, during which the hot air velocity is 1.5 m / s and the material is turned over once every 30 minutes. Then, they are dried at 80°C for 20 minutes, during which the hot air velocity is 2.5 m / s, thus obtaining the blast furnace pulverized coal composite combustion aid.

[0027] In this embodiment, the catalytic oxygenation composite component is prepared by the following method: a supported oxygenation agent is impregnated in an aqueous solution containing cerium ammonium nitrate and copper nitrate, wherein the total concentration of cerium ammonium nitrate and copper nitrate in the aqueous solution is 25 wt%, and the mixture is stirred and adsorbed at 70°C and a speed of 150 r / min for 2 h. After filtration, the mixture is dried at 90°C, and the material is spread to a thickness of 1 cm during the drying process to obtain the catalytic oxygenation composite component; wherein the weight ratio of the supported oxygenation agent, cerium ammonium nitrate, and copper nitrate is 100:30:20.

[0028] In this embodiment, the supported oxygen-enhancing gas was prepared by the following method: Step 1: Mix manganese dioxide and quicklime at a molar ratio of 1:1.5, add deionized water to prepare a slurry with a solid content of 25%, stir and disperse at 400 r / min for 60 min, and hydrothermally react at 95℃ for 3 h. During the hydrothermal reaction, stir continuously at a stirring speed of 200 r / min. Filter, wash, and dry at 100℃ for 6 h to obtain a calcium-manganese composite carrier. Step 2: Mix the calcium-manganese composite carrier with calcium peroxide at a weight ratio of 1:0.8, add water accounting for 8% of the total weight of the mixture, and grind under sealed conditions at a speed of 60 r / min for 2 hours. The grinding media is zirconia balls with a ball-to-material mass ratio of 6:1. Vacuum drying is performed at a vacuum degree of -0.09 MPa. The drying adopts a gradient heating method, first drying at 65℃ for 1 hour, and then heating to 80℃ for 1 hour to obtain the supported oxygen-enriched body.

[0029] Comparative Example 1 A production process for a composite combustion aid for blast furnace pulverized coal injection, compared with Example 1, differs in that: an equal amount of supported oxygen-enhancing gas is used instead of the catalytic oxygen-enhancing composite component. The preparation method of the supported oxygen-enhancing gas in this comparative example is completely consistent with the preparation method of the supported oxygen-enhancing gas in Example 1.

[0030] Comparative Example 2 A production process for a composite combustion aid for blast furnace pulverized coal injection, compared with Example 1, differs in that: an equal amount of calcium-manganese composite carrier is used to replace the catalytic oxygenation composite component. The preparation method of the calcium-manganese composite carrier in this comparative example is completely consistent with the preparation method of the calcium-manganese composite carrier in Example 1.

[0031] Comparative Example 3 A production process for a composite combustion aid for blast furnace pulverized coal injection, compared with Example 1, differs in that: in step S1, by weight, 11 parts of cerium ammonium nitrate, 7 parts of copper nitrate, 15 parts of calcium-manganese composite carrier, 5 parts of calcium peroxide, 10 parts of manganese dioxide, 15 parts of blast furnace dust, 5 parts of quicklime, and 2 parts of binder are mixed and ground in a ball mill to obtain a mixed powder. The preparation method of the calcium-manganese composite carrier in this comparative example is completely consistent with the preparation method of the calcium-manganese composite carrier in Example 1.

[0032] Performance testing: The composite combustion improvers obtained in Examples 1-3 and Comparative Examples 1-3 were mixed evenly with the same batch of pulverized coal for blast furnace injection at a ratio of 2% of the total mass of the mixture to obtain the test samples; another batch of pulverized coal without added combustion improver was taken as a blank control sample, and the following relevant performance tests were performed: 1. Ignition point reduction of pulverized coal: The sample to be tested is placed in a thermogravimetric analyzer and heated from room temperature to 900℃ at a heating rate of 10℃ / min in air atmosphere. The TG curve is recorded. The temperature corresponding to the inflection point of the weight loss of the TG curve is taken as the ignition point. The reduction value is calculated by comparing it with the blank control sample. 2. Pulverized coal combustion rate: The sample to be tested was placed in a tube furnace and burned in an air atmosphere at 900℃ for 30 minutes. The samples were weighed before and after combustion. The pulverized coal combustion rate was calculated according to the ash balance method formula R=[1-(A0×m1) / (A1×m0)]×100%, where R is the pulverized coal combustion rate, m0 is the sample mass before combustion, m1 is the mass of the residue after combustion, A0 is the ash content of the pulverized coal before combustion, and A1 is the ash content of the residue after combustion. 3. Coke Ratio Reduction: Raise the furnace temperature to 900-1000℃, with a blower volume of 15-20 m³ / min, air pressure of 0.15-0.25 MPa, and oxygen enrichment of 3-5%. Using the same batch of raw materials, conduct a blank baseline test, maintaining a constant pulverized coal injection rate for 2-3 hours, and record the coke consumption per ton of iron as the baseline coke ratio. Then, under the same conditions, mix the combustion aid with pulverized coal at a ratio of 2% of the total mass of the mixture and inject it into the furnace, maintaining a constant pulverized coal injection rate, and smelt for 2-3 hours, recording the coke consumption per ton of iron as the test coke ratio. The difference between the two is the coke ratio reduction.

[0033] Each test group was tested three times, and the average value was taken. The test results are shown in Table 1: Table 1 Example 1 23.6 92.4 7.5 Example 2 25.3 93.9 8.8 Example 3 24.8 93.2 8.3 Comparative Example 1 14.8 84.3 3.7 Comparative Example 2 5.6 80.2 1.2 Comparative Example 3 18.3 87.6 5.1 By comparing and analyzing the relevant data in Table 1, it can be seen that Comparative Example 2, using only a calcium-manganese composite carrier, has limited combustion-enhancing effect. In Comparative Example 1, the addition of calcium peroxide to create a supported oxygen-enhancing gas improved combustion performance. Comparative Example 3, by adding cerium-copper catalytic components through physical mixing, further improved performance, but to a limited extent. Examples 1-3, using a catalytic oxygen-enhancing composite component, further improved combustion performance, with Example 2 showing the best overall performance. This indicates that the present invention, by coupling the catalytically active component with the oxygen-enhancing component, effectively strengthens the combustion-enhancing function, exhibiting significant performance advantages compared to physical mixing methods. The resulting composite combustion enhancer achieves significant effects in lowering the ignition point, increasing the combustion rate, and reducing the coke ratio.

[0034] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0035] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A production process for a composite combustion aid for blast furnace pulverized coal injection, characterized in that, Includes the following steps: S1. By weight, 8-15 parts of cerium ammonium nitrate, 5-10 parts of copper nitrate, 25-35 parts of catalytic oxygenation composite component, 10-20 parts of manganese dioxide, 15-25 parts of blast furnace dust, 5-12 parts of quicklime and 2-5 parts of binder are mixed and ground, and then ball-milled to obtain a mixed powder. S2. Mix the powder with water at a weight ratio of 100:(5-10) and granulate for 10-30 minutes to obtain wet granules; S3. The wet material particles are first dried at 35-50℃ for 30-60 minutes, and then dried at 50-80℃ for 20-40 minutes to obtain the composite combustion aid for blast furnace pulverized coal injection.

2. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 1, characterized in that, The preparation method of the catalytic oxygenation composite component includes the following steps: immersing the supported oxygenation body in an aqueous solution containing cerium ammonium nitrate and copper nitrate, stirring and adsorbing at 50-70℃ for 2-4 hours, filtering, and drying at 60-90℃ to obtain the catalytic oxygenation composite component; The total concentration of cerium ammonium nitrate and copper nitrate in the aqueous solution is 10-25 wt%; the weight ratio of the supported oxygen-enhancing agent, cerium ammonium nitrate, and copper nitrate is 100:(15-30):(10-20).

3. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 2, characterized in that, The supported oxygen-enhancing gas is prepared by the following method: Step 1: Mix manganese dioxide and quicklime at a molar ratio of 1:(0.5-1.5), add deionized water to prepare a slurry with a solid content of 15-25%, and perform a hydrothermal reaction at 80-95℃ for 3-6 hours. Filter, wash and dry to obtain a calcium-manganese composite carrier. Step 2: Mix the calcium-manganese composite carrier with calcium peroxide at a weight ratio of 1:(0.3-0.8), add water accounting for 3-8% of the total weight of the mixture, and grind under sealed conditions at a speed of 30-60 r / min for 2-4 hours. Then, vacuum dry to obtain the supported oxygen-enhancing body.

4. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 3, characterized in that, In step two, the drying process uses a gradient heating method, first drying at 60-65℃ for 1-2 hours, and then heating to 75-80℃ for another 1-2 hours.

5. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 1, characterized in that, The binder in step S1 includes any one of pregelatinized starch, sodium carboxymethyl cellulose, and sodium silicate.

6. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 1, characterized in that, In step S1, the fixed carbon content of the blast furnace dust is 15-35%, the total iron content is 20-40%, and the particle size distribution D90 of the blast furnace dust is less than 150μm.

7. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 1, characterized in that, The grinding process in step S1 is carried out intermittently, with a 3-5 minute pause after every 10-15 minutes of operation.

8. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 1, characterized in that, In step S2, water is added by atomizing and spraying during mixing and granulation.

9. The production process of the composite combustion aid for blast furnace pulverized coal injection according to claim 1, characterized in that, The particle size of the wet material in step S2 is 2-8 mm.

10. A composite combustion aid for blast furnace pulverized coal injection, characterized in that, It is prepared by the production process described in any one of claims 1-9.