A refractory material for incinerator lining and a method for producing the same

Abstract

The application discloses a kind of refractory materials for incinerator lining and preparation method thereof, the refractory material includes the raw material as follows mass percentage: calcium hexaluminate 30-50%, fused brown corundum 15-30%, silicon carbide 20-40%, alpha-alumina micro powder 1-10%, silicon micro powder 1-10%, aluminum powder 0.1-2% and water reducing agent 0.1-0.5%;The calcium hexaluminate is modified calcium hexaluminate, which is obtained by mixing and adsorbing after coating calcium hexaluminate with silica sol and cationized graphene.The refractory material for incinerator lining and preparation method thereof proposed in the application have outstanding alkali corrosion resistance, excellent room temperature / high temperature mechanical properties, thermal shock resistance and oxygen corrosion resistance, thus can greatly meet the needs of incinerator lining.

Description

Technical Field

[0001] This invention belongs to the field of refractory materials technology, and particularly relates to a refractory material for incinerator lining and its preparation method. Background Technology

[0002] An incinerator is an environmentally friendly device widely used for the treatment of industrial waste, municipal solid waste, and medical waste. It consists of a pretreatment system, an incineration system, a flue gas and biochemical dust removal system, and an auxiliary ignition system. Waste is burned at high temperatures in the incinerator furnace, becoming exhaust gas. This exhaust gas then enters a secondary combustion chamber, where it undergoes complete combustion and dust removal before being released into the atmosphere. This process not only achieves harmless treatment but also effectively reduces waste volume, lowers the content of toxic substances, and recovers energy. To achieve this goal, the interior of the incinerator needs to possess high strength, wear resistance, high-temperature resistance, and chemical corrosion resistance. Therefore, the refractory materials used for the incinerator lining are crucial.

[0003] Traditional refractory materials used for incinerator linings are mainly silicon carbide, aluminosilicate, and aluminosilicate refractories. Silicon carbide refractories possess high thermal shock stability, good erosion resistance, and SiC is non-wetting. However, silicon carbide refractories are difficult to sinter during preparation, resulting in a loose internal structure and low density. Furthermore, their application is limited to reducing atmospheres. Aluminosilicate refractories are high-alumina refractories with Al₂O₃ as the main component and a small amount of Cr₂O₃. Cr₂O₃ and Al₂O₃ form a continuous solid solution (Al₂O₃) at high temperatures. 1-x ,Cr x )2O3, and at high temperatures, it produces a high-viscosity phase, effectively improving the erosion resistance and impermeability of refractory materials. However, during use, it will produce Cr 6+ It is carcinogenic to humans and causes serious pollution to soil and water sources. Aluminosilicate refractories are mainly composed of mullite (3Al2O3·2SiO2). The mullite crystals have a plate-like and columnar structure, which gives them high mechanical properties and chemical stability. However, in the working environment, aluminosilicate refractories are prone to chemical reactions with the alkaline slag in waste liquid treatment furnaces, forming nepheline-like expanded phases and low-melting-point silicate phases, which cause serious damage to the refractories.

[0004] Since mainstream aluminosilicate refractories cannot resist the erosion of alkali metal oxides, the main control method is to introduce additives to form a dense layer or high-viscosity liquid phase at the interface between the refractory material and molten salt, thereby hindering the penetration of alkali-containing molten salts. Studies have shown that introducing SiC or elemental Si into the refractory material can block surface pores, improve material density, and simultaneously strengthen the interfacial bonding between aggregates and matrix to improve its impermeability. However, the formed SiO2 is highly susceptible to erosion by alkali metal ions; the higher the SiO2 content, the faster the erosion rate. Other additives include ZrB2 and BN. βAdditives such as Sialon and BaSO4 are designed to form a dense phase to improve the resistance of refractory materials to slag erosion and penetration. However, BaSO4 is non-wetting. ZrB2 and BN, after being oxidized by molten salt, can fill pores and reduce slag erosion. β - The SiO2 formed after Sialon oxidation can inhibit the corrosion reaction and has good resistance to corrosion of molten aluminum and NaCl-KCl melt.

[0005] In conclusion, studying the causes and influencing factors of alkali corrosion of aluminosilicate refractories and developing refractories for incinerator linings will meet the needs of chemical and medical waste treatment, while also promoting the vigorous development of my country's refractory materials industry. Summary of the Invention

[0006] Based on the above-mentioned technical problems, the present invention proposes a refractory material for incinerator lining and its preparation method. The refractory material has outstanding resistance to alkali erosion, excellent mechanical properties at room temperature / high temperature, thermal shock resistance and oxygen erosion resistance, and thus can greatly meet the needs of incinerator lining.

[0007] The present invention proposes a refractory material for incinerator lining, comprising the following raw materials in the following mass percentages: 30-50% calcium hexaaluminate, 15-30% fused brown corundum, 20-40% silicon carbide, 1-10% α-alumina micro powder, 1-10% silicon micro powder, 0.1-2% metallic aluminum powder, and 0.1-0.5% water-reducing agent;

[0008] The calcium hexaaluminate is a modified calcium hexaaluminate, which is obtained by coating calcium hexaaluminate with silica sol and then mixing and adsorbing it with cationic graphene.

[0009] In this invention, calcium hexaaluminate, fused brown fused alumina, and silicon carbide are used as the main matrix. On the one hand, calcium hexaaluminate has the characteristics of plate-like crystals, high melting point, and excellent high-temperature mechanical properties. Unlike other alumina-calcium compounds, calcium hexaaluminate does not react with water, and its high-temperature chemical properties are stable. It has strong resistance to corrosion by oxidizing and reducing gases. When calcium hexaaluminate particles are used as aggregate, the resistance of refractory materials to alkaline corrosion in incinerators can be significantly improved. On the other hand, fused brown fused alumina has high density and strength, and strong resistance to thermal stress. It can withstand high-temperature fracture to a certain extent and reduce the generation of thermal shock cracks. When used as aggregate, it is beneficial to improve the thermal shock resistance of refractory materials. Furthermore, silicon carbide has strong resistance to slag erosion. Using silicon carbide as a matrix can significantly improve the slag erosion resistance of refractory materials.

[0010] Preferably, the calcium hexaaluminate has an Al₂O₃ content of ≥90 wt% and a CaO content of ≥8 wt%.

[0011] The particle size distribution of the calcium hexaaluminate includes: 30-40 wt% of calcium hexaaluminate with a particle size of less than 6 mm and greater than or equal to 3 mm, and 60-70 wt% of calcium hexaaluminate with a particle size of less than 3 mm and greater than or equal to 1 mm.

[0012] Preferably, the calcium hexaaluminate is modified calcium hexaaluminate, which is obtained by coating calcium hexaaluminate with silica sol and then mixing and adsorbing it with cationic graphene.

[0013] The cationic graphene is obtained by ring-opening substitution reaction of graphene oxide and 2,3-epoxypropyltrimethylammonium chloride.

[0014] In this invention, calcium hexaaluminate is coated with silica sol. The silica sol surface is rich in negatively charged centers such as hydroxyl groups, which can attract the positively charged centers of ammonium salts on the surface of cationic graphene. This allows graphene oxide to be stably fixed on the surface of calcium hexaaluminate. This not only enhances the mechanical properties and impermeability of calcium hexaaluminate, but also forms a glassy phase structure of SiC and SiO2 at high temperatures. Calcium hexaaluminate can absorb this glassy phase and react in situ to form anorthite mineral. Anorthite has a high melting point. Since this process is accompanied by a certain volume expansion, on the one hand, it helps to block pores, reduce O2 diffusion, and improve the oxidation resistance of the material. On the other hand, the refractory material can still maintain excellent mechanical properties and volume stability in extreme high-temperature environments.

[0015] In this invention, the cationic graphene is produced by a ring-opening substitution reaction between the hydroxyl groups on the surface of graphene oxide and the epoxy groups of 2,3-epoxypropyltrimethylammonium chloride, thereby grafting a quaternary ammonium salt onto the surface of graphene oxide to form a positively charged ammonium salt center; the structural schematic of the cationic graphene is shown below:

[0016] Preferably, the Al2O3 content of the fused brown corundum is ≥94 wt%;

[0017] The particle size distribution of the fused brown fused alumina includes: 30-50 wt% of fused brown fused alumina with a particle size of less than 5 mm and greater than or equal to 3 mm, 15-35 wt% of fused brown fused alumina with a particle size of less than 3 mm and greater than or equal to 1 mm, and 25-45 wt% of fused brown fused alumina with a particle size of less than 1 mm and greater than or equal to 0.088 mm.

[0018] Preferably, the silicon carbide has SiC ≥ 98 wt%;

[0019] The particle size distribution of the silicon carbide includes: silicon carbide with a particle size of less than 1 mm and greater than or equal to 0.088 mm accounts for 40-60 wt%, and silicon carbide with a particle size of less than 0.088 mm accounts for 40-60 wt%.

[0020] Preferably, the α-alumina micro powder has an Al2O3 content of ≥97 wt%.

[0021] The particle size of the α-alumina micro powder is ≤8μm.

[0022] Preferably, the SiO2 content of the silicon micropowder is ≥92wt%;

[0023] The particle size of the silicon micropowder is ≤1μm.

[0024] Preferably, the surface of the aluminum powder is coated with an amphoteric compound;

[0025] Preferably, the aluminum powder coated with the amphoteric compound is prepared by the following method: ethyl orthosilicate and N,N-diethylaminopropyltrimethoxysilane are hydrolyzed and condensed on the surface of the aluminum powder to form tertiary amino silica-coated aluminum powder, which is then subjected to a quaternization reaction with sodium chloroacetate to obtain the aluminum powder coated with the amphoteric compound.

[0026] In this invention, the aluminum powder is hydrolyzed and polycondensed on the surface of the aluminum powder using tetraethyl orthosilicate and N,N-diethylaminopropyltrimethoxysilane to obtain an aluminum powder@tertiary amino silica composite material. Subsequently, the aluminum powder@tertiary amino silica composite material is subjected to a quaternization reaction with sodium chloroacetate to obtain an aluminum powder@silica composite material simultaneously grafted with quaternary ammonium salt and sodium carboxylate. Its specific structure is illustrated below:

[0027]

[0028] The aforementioned aluminum powder coated with amphoteric compounds has several advantages. First, the aluminum powder is encapsulated within silica, which isolates it from air and prevents oxidation during storage. Furthermore, silica reacts with alumina and other materials at high temperatures to form a mullite structure, which possesses a high melting point and creep resistance, further enhancing the high-temperature resistance and mechanical properties of the refractory material. Second, the silica surface is also grafted with amphoteric compounds of quaternary ammonium salt and sodium carboxylate. Sodium carboxylate, acting as a negatively charged center, attracts the cationic graphene on the modified calcium hexaaluminate surface, effectively acting as an antioxidant for the aluminum powder around the carbon source of graphene. This significantly improves the oxidation resistance of the carbonaceous raw material, thereby greatly enhancing the mechanical properties of the refractory material. Simultaneously, the quaternary ammonium salt attracts the water-reducing agent, ensuring the dispersibility of the aluminum powder and thus providing stronger antioxidant and mechanical strengthening effects.

[0029] Preferably, the water-reducing agent is at least one of sodium tripolyphosphate, sodium hexametaphosphate, or sodium naphthalenesulfonate formaldehyde condensate.

[0030] The present invention also proposes a method for preparing the above-mentioned refractory material for incinerator lining, comprising: mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water reducing agent, then adding water and mixing, curing at room temperature, demolding, drying, and heat treatment to obtain the refractory material for incinerator lining.

[0031] Compared with the prior art, the refractory material for the incinerator lining of the present invention is mainly composed of a mixed matrix formed by calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder and metallic aluminum powder, and is made of water-reducing agent and water. The resulting refractory material has the characteristics of excellent mechanical properties at medium and high temperatures, strong resistance to alkali corrosion, good thermal shock stability, long service life and energy saving and environmental protection. Attached Figure Description

[0032] Figure 1 The image shows a SEM image of the refractory material described in Example 1.

[0033] Figure 2 The image shown is the FTIR image of the aluminum powder described in Example 4. Detailed Implementation

[0034] The present invention will now be described in detail through specific embodiments. However, these embodiments are clearly provided for illustrative purposes and are not intended to limit the scope of the present invention.

[0035] The calcium hexaaluminate has an Al2O3 content of ≥90wt% and a CaO content of ≥8wt%. The particle size distribution of the calcium hexaaluminate includes: 35wt% of calcium hexaaluminate with a particle size of less than 6mm and greater than or equal to 3mm, and 65wt% of calcium hexaaluminate with a particle size of less than 3mm and greater than or equal to 1mm.

[0036] The Al2O3 content of fused brown fused alumina is ≥94wt%; the particle size distribution of fused brown fused alumina includes: 40wt% of fused brown fused alumina with a particle size less than 5mm and greater than or equal to 3mm, 25% of fused brown fused alumina with a particle size less than 3mm and greater than or equal to 1mm, and 35wt% of fused brown fused alumina with a particle size less than 1mm and greater than or equal to 0.088mm.

[0037] The silicon carbide contains ≥98 wt% SiC; the particle size distribution of the silicon carbide includes: 50 wt% silicon carbide with a particle size less than 1 mm and greater than or equal to 0.088 mm, and 50 wt% silicon carbide with a particle size less than 0.088 mm.

[0038] The Al2O3 content of the α-alumina micro powder is ≥97wt%; the particle size of the α-alumina micro powder is ≤8μm; the SiO2 content of the silicon micro powder is ≥92wt%; the particle size of the silicon micro powder is ≤1μm.

[0039] The silica sol has a SiO2 content of 30wt% and a pH value of 9-11; the aluminum powder has an Al content of ≥98.5wt%; the aluminum powder has a particle size of ≤0.088mm; the graphene oxide has a sheet diameter of 0.5-5μm, a thickness of 0.8-1.2nm, and a purity of ≥99%.

[0040] Example 1

[0041] A refractory material for incinerator lining, comprising, by weight percentage: 40% calcium hexaaluminate, 20.5% fused brown corundum, 28% silicon carbide, 5% α-alumina micropowder, 5% silicon micropowder, 1.2% metallic aluminum powder, and 0.3% water-reducing agent;

[0042] The calcium hexaaluminate is a modified calcium hexaaluminate, which is prepared by the following method:

[0043] Graphene oxide was dispersed evenly in water, and then 5 wt% (by weight of graphene oxide) of 2,3-epoxypropyltrimethylammonium chloride was added. The mixture was heated to 60°C and stirred for 12 hours. After filtration, washing with water, and drying, cationic graphene was obtained. 10 wt% (by weight of calcium hexaaluminate) of silica sol was added to calcium hexaaluminate and stirred for 30 minutes to uniformly coat the surface of calcium hexaaluminate with silica sol. The calcium hexaaluminate coated with silica sol was added to an aqueous solution of cationic graphene, where the mass of cationic graphene was 1.5 wt% of calcium hexaaluminate. After stirring for 1 hour, the mixture was dried at 150°C to obtain the modified calcium hexaaluminate.

[0044] The water-reducing agent is sodium tripolyphosphate.

[0045] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0046] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0047] Example 2

[0048] A refractory material for incinerator lining, comprising, by weight percentage: 35% calcium hexaaluminate, 30% fused brown corundum, 20% silicon carbide, 10% α-alumina micro powder, 3% silicon micro powder, 1.9% metallic aluminum powder, and 0.1% water-reducing agent;

[0049] The calcium hexaaluminate is a modified calcium hexaaluminate, which is prepared by the method described in Example 1;

[0050] The water-reducing agent is sodium hexametaphosphate.

[0051] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0052] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0053] Example 3

[0054] A refractory material for incinerator lining, comprising, by weight percentage: 45% calcium hexaaluminate, 15% fused brown corundum, 27.5% silicon carbide, 1.7% α-alumina micropowder, 10% silicon micropowder, 0.3% metallic aluminum powder, and 0.5% water-reducing agent;

[0055] The calcium hexaaluminate is a modified calcium hexaaluminate, which is prepared by the method described in Example 1;

[0056] The water-reducing agent is sodium naphthalene sulfonate formaldehyde condensate.

[0057] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0058] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0059] Example 4

[0060] A refractory material for incinerator lining, comprising, by weight percentage: 40% calcium hexaaluminate, 20.5% fused brown corundum, 28% silicon carbide, 5% α-alumina micropowder, 5% silicon micropowder, 1.2% metallic aluminum powder, and 0.3% water-reducing agent;

[0061] The calcium hexaaluminate is a modified calcium hexaaluminate, which is prepared by the method described in Example 1;

[0062] The aluminum powder is an aluminum powder with an amphoteric compound coated on its surface, and it is prepared by the following method:

[0063] Aluminum powder was dispersed evenly in anhydrous ethanol, and then 30 wt% tetraethyl orthosilicate and 10 wt% N,N-diethylaminopropyltrimethoxysilane were added. After ultrasonic dispersion, a dilute ammonia solution (2 wt%) three times the weight of the aluminum powder was slowly added dropwise. The mixture was heated to 50°C and stirred for 2 hours to obtain aluminum powder coated with tertiary amino silica. The aluminum powder coated with tertiary amino silica was then dispersed evenly in ethanol, and then 6 wt% sodium chloroacetate was added. The mixture was heated to 60°C and stirred for 12 hours. After filtration, washing, and drying, the aluminum powder with the amphoteric compound coating was obtained.

[0064] The water-reducing agent is sodium tripolyphosphate.

[0065] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0066] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0067] Comparative Example 1

[0068] A refractory material for incinerator lining, comprising, by weight percentage: 40% calcium hexaaluminate, 20.5% fused brown corundum, 28% silicon carbide, 5% α-alumina micropowder, 5% silicon micropowder, 1.2% metallic aluminum powder, and 0.3% water-reducing agent;

[0069] The water-reducing agent is sodium tripolyphosphate.

[0070] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0071] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0072] Comparative Example 2

[0073] A refractory material for incinerator lining, comprising, by weight percentage: 40% calcium hexaaluminate, 20.5% fused brown corundum, 28% silicon carbide, 5% α-alumina micropowder, 5% silicon micropowder, 1.2% metallic aluminum powder, and 0.3% water-reducing agent;

[0074] The calcium hexaaluminate is a modified calcium hexaaluminate, which is prepared by the following method:

[0075] Add 10 wt% silica sol to calcium hexaaluminate and stir for 30 min to uniformly coat the surface of calcium hexaaluminate with silica sol. Add the silica sol-coated calcium hexaaluminate to an aqueous solution of graphene oxide, where the mass of graphene oxide is 1.5 wt% of calcium hexaaluminate. Stir for 1 h and dry at 150 °C to obtain the modified calcium hexaaluminate.

[0076] The water-reducing agent is sodium tripolyphosphate.

[0077] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0078] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0079] Comparative Example 3

[0080] A refractory material for incinerator lining, comprising, by weight percentage: 40% calcium hexaaluminate, 20.5% fused brown corundum, 28% silicon carbide, 5% α-alumina micropowder, 5% silicon micropowder, 1.2% metallic aluminum powder, and 0.3% water-reducing agent;

[0081] The calcium hexaaluminate is a modified calcium hexaaluminate, which is prepared by the method described in Example 1;

[0082] The aluminum powder is aluminum powder with a surface coated with silica, and it is prepared by the following method:

[0083] Metallic aluminum powder was added to anhydrous ethanol and dispersed evenly. Then, 30 wt% of tetraethyl orthosilicate of metallic aluminum powder was added and ultrasonically dispersed evenly. Then, a dilute ammonia solution (2 wt%) with 3 times the weight of metallic aluminum powder was slowly added dropwise. The mixture was heated to 50°C and stirred for 2 hours to obtain a metallic aluminum powder@silica composite material, which is the metallic aluminum powder with silica coating.

[0084] The water-reducing agent is sodium tripolyphosphate.

[0085] The preparation method of the above-mentioned refractory material for incinerator lining specifically includes:

[0086] After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added to the resulting mixture and mixed evenly. The amount of water is controlled to be 3wt%. After curing at room temperature, the mixture is demolded, dried, and then heat-treated to obtain the refractory material for the incinerator lining.

[0087] Experimental test:

[0088] The refractory materials obtained in the examples and comparative examples were dried at 110°C for 24 hours and then kept at 1500°C for 3 hours. The linear shrinkage rate (GB / T5988-2007), flexural strength (GB / T3001-2007), compressive strength (GB / T5072-2008), thermal shock resistance, alkali erosion resistance and oxidation index were tested respectively. The specific results are shown in Table 1.

[0089] Thermal shock resistance was determined based on the thermal shock fatigue test proposed in "Research on Evaluation of Thermal Shock Fatigue Behavior of Refractory Materials", which measured the retention rate of residual flexural strength after 10 cycles of thermal shock fatigue testing and air cooling. Alkali corrosion resistance was determined by immersing the refractory material in a 10% sodium hydroxide solution, curing it at 80℃ for 24 hours, rinsing it with distilled water, and drying it, comparing the mass loss rate of the samples before and after immersion. Oxidation index was determined by oxidizing the refractory material in an air atmosphere at 1500℃ for 3 hours, and analyzing the ratio of the oxidized area of ​​the fracture surface to the initial area using an image method.

[0090]

[0091] As can be seen from the table above, the refractory material obtained in the examples is superior to that in the comparative examples in all aspects. Therefore, it can be seen that the refractory material of the present invention has outstanding resistance to alkali erosion, excellent mechanical properties at room temperature / high temperature, thermal shock resistance and resistance to oxygen erosion, and can thus greatly meet the needs of the lining of incinerators.

[0092] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A refractory material for incinerator lining, characterized in that, The raw materials include the following percentages by weight: 30-50% calcium hexaaluminate, 15-30% fused brown corundum, 20-40% silicon carbide, 1-10% α-alumina micro powder, 1-10% silicon micro powder, 0.1-2% metallic aluminum powder, and 0.1-0.5% water-reducing agent; The calcium hexaaluminate is a modified calcium hexaaluminate, which is obtained by coating calcium hexaaluminate with silica sol and then mixing and adsorbing it with cationic graphene.

2. The refractory material for incinerator lining according to claim 1, characterized in that, The calcium hexaaluminate has an Al2O3 content of ≥90wt% and a CaO content of ≥8wt%. The particle size distribution of the calcium hexaaluminate includes: 30-40 wt% of calcium hexaaluminate with a particle size of less than 6 mm and greater than or equal to 3 mm, and 60-70 wt% of calcium hexaaluminate with a particle size of less than 3 mm and greater than or equal to 1 mm.

3. The refractory material for incinerator lining according to claim 1, characterized in that, The cationic graphene is obtained by ring-opening substitution reaction of graphene oxide and 2,3-epoxypropyltrimethylammonium chloride.

4. The refractory material for incinerator lining according to any one of claims 1-3, characterized in that, The fused brown corundum has an Al2O3 content of ≥94 wt%. The particle size distribution of the fused brown fused alumina includes: 30-50 wt% of fused brown fused alumina with a particle size of less than 5 mm and greater than or equal to 3 mm, 15-35 wt% of fused brown fused alumina with a particle size of less than 3 mm and greater than or equal to 1 mm, and 25-45 wt% of fused brown fused alumina with a particle size of less than 1 mm and greater than or equal to 0.088 mm.

5. The refractory material for incinerator lining according to any one of claims 1-3, characterized in that, The silicon carbide has SiC ≥ 98 wt%; The particle size distribution of the silicon carbide includes: silicon carbide with a particle size of less than 1 mm and greater than or equal to 0.088 mm accounts for 40-60 wt%, and silicon carbide with a particle size of less than 0.088 mm accounts for 40-60 wt%.

6. The refractory material for incinerator lining according to any one of claims 1-3, characterized in that, The α-alumina micro powder has an Al2O3 content of ≥97 wt%. The particle size of the α-alumina micro powder is ≤8μm.

7. The refractory material for incinerator lining according to any one of claims 1-3, characterized in that, The silicon micropowder has an SiO2 content of ≥92wt%; The particle size of the silicon micropowder is ≤1μm.

8. The refractory material for incinerator lining according to any one of claims 1-3, characterized in that, The surface of the aluminum powder is coated with an amphoteric compound; The aluminum powder coated with the amphoteric compound is prepared by the following method: tetraethyl orthosilicate and N,N-diethylaminopropyltrimethoxysilane are hydrolyzed and polycondensed on the surface of aluminum powder to form aluminum powder coated with tertiary amino silica, and then subjected to a quaternization reaction with sodium chloroacetate to obtain the aluminum powder coated with the amphoteric compound.

9. The refractory material for incinerator lining according to any one of claims 1-3, characterized in that, The water-reducing agent is at least one of sodium tripolyphosphate, sodium hexametaphosphate, or sodium naphthalene sulfonate formaldehyde condensate.

10. A method for preparing a refractory material for an incinerator lining according to any one of claims 1-9, characterized in that, include: After mixing calcium hexaaluminate, fused brown corundum, silicon carbide, α-alumina micro powder, silicon micro powder, metallic aluminum powder and water-reducing agent, water is added and mixed again. After curing at room temperature, the mixture is demolded, dried, and heat-treated to obtain the refractory material for the incinerator lining.

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