Refractory castable for low nickel matte chute and preparation method of refractory castable

Abstract

The invention provides a refractory castable for a low nickel matte chute and a preparation method of the refractory castable. The preparation raw materials of the castable comprise the following components in parts by mass: 6-15 parts of alumina particles or recycled particles thereof, 25-40 parts of corundum particles or recycled particles thereof, 20-30 parts of silicon carbide particles or recycled particles thereof, 1-10 parts of corundum fine powder, 5-15 parts of silicon carbide fine powder, 4-10 parts of alumina micro powder, 3.4-10 parts of a binding agent, 3-10 parts of an antioxidant and 2-4 parts of a carbon material. Wherein the antioxidant is a combination of metal silicon powder, silicon carbide micro powder and Si-N-O micro powder. In the castable, the metal silicon powder, the silicon carbide micro powder and the Si-N-O micro powder can form columnar mullite and O '-sialon phases in a matrix, so that the castable has a remarkable toughening effect; silicon carbide with a higher proportion is added, and particles, fine powder and micro powder are matched in multi-level granularity, so that the performance characteristics of non-wetting, oxidation resistance, high hardness and wear resistance of the silicon carbide are better exerted.

Description

Technical Field

[0001] The present invention belongs to the technical field of refractory materials, and particularly relates to a refractory castable for a low nickel matte launder and a preparation method thereof. Background Art

[0002] In the process of smelting nickel from nickel sulfide ores (such as pentlandite), an intermediate product, low nickel matte, is produced, with a nickel content of about 20% - 40%, and also containing impurities such as copper, iron, and sulfur. The nickel sulfide ore is smelted at a high temperature (1200°C - 1400°C) to produce low nickel matte (Ni + Cu content about 20% - 40%) and slag (mainly FeSiO3). The viscosity of low nickel matte in the molten state is usually 0.01 - 0.1 Pa·s, close to that of liquid iron, much lower than that of the slag, belonging to a melt with good fluidity, and its viscosity decreases significantly with the increase in temperature. The low nickel matte launder is a trough-shaped device for transporting and transferring low nickel matte, and the low nickel matte launder is usually prepared from refractory materials. The erosion of the low nickel matte melt on the refractory material container is mainly through the combined action of chemical penetration, oxidation-reduction reaction, and thermo-mechanical erosion.

[0003] Compared with blast furnace ironmaking, the chemical erosion, penetration, and oxidation of low nickel matte on refractory materials are more intense. This is because, firstly, the Ni and Cu metal phases in low nickel matte are easy to penetrate the pores of refractory materials and further react with SiC in the Al2O3 - SiC refractory materials, Ni + SiC → Ni - Si alloy + C, thus destroying the SiC reinforcement phase of the refractory materials, leading to the destruction of the material structure and rapid damage. Secondly, due to the high content of FeS and Cu2S in the low nickel matte slag, the permeability to refractory materials is enhanced, and the high SiO2 / Al2O3 ratio accelerates the slagging reaction. Therefore, a large amount of slag and high impurity content are the main reasons for the damage of refractory materials. In the process of low nickel matte smelting, an oxygen-enriched slag-making process is also used to remove impurities by slagging, but the oxides in the slag will cause the oxidation of the matrix in the refractory materials, making the structure loose, the strength decrease, and the erosion and damage aggravated.

[0004] Chinese patent document with the publication number CN202411385599 discloses an Al2O3 - SiC - C refractory castable product and a preparation method thereof. Its ingredients mainly include corundum particles, silicon carbide particles, corundum fine powder, silicon carbide fine powder, activated alumina micropowder, binder, antioxidant, additive, etc. The binder is light-burned magnesia powder, and the antioxidant is passivated metallic aluminum powder. This castable product has high service strength and good resistance to molten slag erosion and penetration when used in the iron runner, but when used in the low nickel matte launder, its antioxidant performance, erosion resistance, penetration resistance, and high-temperature strength performance are insufficient, and its binder will cause volume change of the castable, resulting in an increase in porosity and a decrease in strength. Summary of the Invention

[0005] The technical problem solved by the present invention is to provide a refractory castable for low-grade nickel matte launder and its preparation method. By adding an antioxidant composed of a combination of metallic silicon powder, silicon carbide micropowder and Si-N-O micropowder, columnar mullite and solid solution O'-sialon phase can be formed in the matrix, which has a significant strengthening and toughening effect. By adding a higher proportion of silicon carbide and adopting a multi-stage particle size distribution of particles, fine powder and micropowder, the performance characteristics of silicon carbide such as non-wetting, oxidation resistance and high hardness wear resistance can be better exerted, significantly improving the high-temperature strength, thermal shock stability, erosion resistance and penetration resistance of the castable.

[0006] To solve the above problems, one aspect of the present invention provides a refractory castable for low-grade nickel matte launder, and the preparation raw materials thereof include the following components in parts by mass: 6-15 parts of bauxite particles or their recycled particle materials, 25-40 parts of corundum particles or their recycled particle materials, 20-30 parts of silicon carbide particles or their recycled particle materials, 1-10 parts of corundum fine powder, 5-15 parts of silicon carbide fine powder, 4-10 parts of alumina micropowder, 3.4-10 parts of binder, 3-10 parts of antioxidant, 2-4 parts of carbonaceous material; wherein, the antioxidant is a combination of metallic silicon powder, silicon carbide micropowder and Si-N-O micropowder.

[0007] Preferably, the preparation raw materials thereof include the following components in parts by mass: 6-10 parts of bauxite particles or their recycled particle materials, 28-35 parts of corundum particles or their recycled particle materials, 25-30 parts of silicon carbide particles or their recycled particle materials, 1-5 parts of corundum fine powder, 6-10 parts of silicon carbide fine powder, 6-10 parts of alumina micropowder, 3.4-7 parts of binder, 5-9 parts of antioxidant, 2-3 parts of carbonaceous material.

[0008] Preferably, the mass ratio of alumina micropowder to antioxidant is 1:0.625-1.25.

[0009] Preferably, the antioxidant is a combination of metallic silicon powder, silicon carbide micropowder and Si-N-O micropowder with a mass ratio of 2:2-4:2-4.

[0010] Preferably, the binder is a mixture of silica micropowder and aluminate cement with a mass ratio of 1:0.5-1.5, or the binder is a mixture of silica micropowder, Secar-Z and aluminate cement with a mass ratio of 0.7:2-3:0.5-1.5, or the binder is a mixture of silica micropowder, silica sol and aluminate cement with a mass ratio of 1.5:4-6:0.6-0.8.

[0011] Preferably, it further includes the following components in mass percentage: 0.1%-0.3% of water reducer, 0.2%-0.8% of boron carbide, 0.07%-0.25% of explosion-proof agent.

[0012] Preferably, the silicon carbide particles or their recycled particulate materials are composed of silicon carbide or its recycled particulate materials with a particle size of 1 - 3 mm and silicon carbide or its recycled particulate materials with a particle size of 0.1 - 1 mm, mixed in a mass ratio of 10 - 13:14 - 17; The silicon carbide fine powder is composed of silicon carbide fine powder with 200 mesh and silicon carbide fine powder with 325 mesh, mixed in a mass ratio of 5 - 10:1 - 4; The particle size of the silicon carbide micropowder is 1 - 5 μm; The corundum particles or their recycled particulate materials include brown corundum particles or their recycled particulate materials with a particle size of 5 - 8 mm, brown corundum particles or their recycled particulate materials with a particle size of 3 - 5 mm, and dense corundum particles or their recycled particulate materials with a particle size of 1 - 3 mm; the mass ratio of bauxite particles or their recycled particulate materials with a particle size of 8 - 15 mm, brown corundum particles or their recycled particulate materials with a particle size of 5 - 8 mm, brown corundum particles or their recycled particulate materials with a particle size of 3 - 5 mm, and dense corundum particles or their recycled particulate materials with a particle size of 1 - 3 mm is 6 - 10:12 - 17:14 - 17:2 - 5; The particle size of the corundum fine powder is 200 mesh; The particle size of the bauxite particles or their recycled particulate materials is 8 - 15 mm; The particle size of the metallic silicon powder is 3 - 40 μm; The particle size of the Si - N - O micropowder is 0.5 - 20 μm; The particle size of the alumina micropowder is 2 - 5 μm; The particle size of the carbonaceous material is 0.001 - 2 mm; The particle size of the boron carbide is 325 mesh.

[0013] Preferably, the content of Al2O3 in the bauxite particles is not less than 87 wt%, the content of Fe2O3 is not higher than 1.55%, the porosity is < 5.5%, and the bulk density > 3.3 g / cm 3 ; The content of Al2O3 in the recycled bauxite particulate materials and recycled corundum particulate materials is not less than 90 wt%, and the bulk density ≥ 3.7 g / cm 3 ; The SiC content in the silicon carbide particles is not less than 92 wt%; The SiC content in the silicon carbide fine powder is not less than 97 wt%; The SiO2 content in the silica micropowder is not less than 92 wt%; The SiO2 content in the silica sol is 39 wt% - 41 wt%, at 25 °C, the pH is 9 - 10.5, and the viscosity is 10 - 20 mPa·s; The Al2O3 content in the aluminate cement is not less than 70 wt%.

[0014] Preferably, the carbon material is one or a combination of several of spherical pitch, graphite, and carbon black; The water reducing agent is one or a combination of several of SP610, FS20, FDN, DF401, PC8159, and BC-2; The explosion-proof agent is one or a combination of several of metallic aluminum powder and explosion-proof fiber.

[0015] Another aspect of the present invention provides a preparation method of the refractory castable for the low nickel matte launder as described above, comprising the following steps: S1. Mix the raw materials of the antioxidant to obtain an antioxidant mixture; S2. Mix the antioxidant mixture and the binder to obtain a premix; S3. Mix bauxite particles or their recycled particle materials, corundum particles or their recycled particle materials, silicon carbide particles or their recycled particle materials, corundum fine powder, silicon carbide fine powder, alumina micro powder, carbon material, and the premix to obtain the refractory castable for the low nickel matte launder, wherein the silica sol in the binder is added during use.

[0016] Compared with the prior art, the present invention has the following beneficial effects: For the refractory castable for the low nickel matte launder of the present invention, an antioxidant composed of a combination of metallic silicon powder, silicon carbide micro powder, and Si-N-O micro powder is added. First, under the action of high temperature, the metallic silicon powder, silicon carbide micro powder, and Si-N-O micro powder can form a continuous glaze layer on the surface of the castable to block pores and coat the refractory material to prevent the refractory material from being further oxidized; second, each component in the antioxidant is an ultrafine powder. By using the filling effect of the ultrafine powder on the micropores in the matrix of the castable, the density of the castable is improved, the oxidation of the castable by oxygen or oxygen-rich substances is reduced, the density of the matrix is increased, and the solid-phase sintering strength of the castable can be improved earlier and faster, so that the refractory castable for the low nickel matte launder has a lower porosity, stronger antioxidant and slag erosion resistance. More importantly, and the key innovation point of the present invention is that in the antioxidant, SiO2 generated after the oxidation of metallic silicon powder and Si-N-O micro powder, and the silica micro powder in the binder react with the alumina micro powder in the matrix to form columnar mullite; at high temperature, the SiO gas phase and SiNO formed by the oxidation of metallic silicon powder and Si-N-O micro powder react with the alumina micro powder in the matrix to form a substitutional solid solution O'-sialon phase; the metallic silicon powder reacts with the carbon source in the matrix to form SiC whiskers. The whiskers, columnar crystals, and O'-sialon phase formed by the above reactions have a significant strengthening and toughening effect, which can significantly improve the high-temperature strength, thermal shock stability, erosion resistance, and penetration resistance of the castable. In addition, the above ultrafine powder has high activity and reacts with the alumina micro powder in the matrix to form a mullite phase, and the slight volume expansion further fills the pores generated in the castable, improving the antioxidant performance and strength of the castable.

[0017] The refractory castable for matte launder of the present invention uses a higher proportion of silicon carbide compared with the existing trough castable. Moreover, the silicon carbide adopts a multi-stage particle size combination of particles, fine powder and micro powder, which can improve the uniformity of the silicon carbide distribution and better exert the performance characteristics of silicon carbide, such as non-wetting, oxidation resistance (forming an oxide film on the surface to slow down continuous oxidation) and high hardness and wear resistance. It can effectively cope with the high permeability, oxidability and scouring effect of the matte melt, thereby improving the service life.

[0018] The castable of the present invention is applied to the matte launder, has strong applicability, convenient construction, can produce various special-shaped prefabricated parts or be used for local hot repair and maintenance, and has significant advantages in aspects such as saving resources, reducing costs, improving construction efficiency, and improving service life. Specific embodiments

[0019] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0020] For the launder used in matte smelting, due to site restrictions, whether it is prefabricated parts or castable construction, the working layer has a thin thickness. Affected by the low viscosity, strong penetration, large slag volume of the matte melt, the chemical erosion of refractories is severe, and the scouring strength of the melt flow on the refractories is high. The commonly used trough castable cannot meet the requirements of slag resistance and thermal shock stability during high-temperature service on the matte launder, resulting in abnormal erosion and spalling of the refractories and affecting normal use.

[0021] One aspect of the embodiment of the present invention provides a refractory castable for matte launder, and its preparation raw materials include the following components in parts by mass: 6-15 parts of bauxite particles or their recycled particle materials, 25-40 parts of corundum particles or their recycled particle materials, 20-30 parts of silicon carbide particles or their recycled particle materials, 1-10 parts of corundum fine powder, 5-15 parts of silicon carbide fine powder, 4-10 parts of alumina micro powder, 3.4-10 parts of binder, 3-10 parts of antioxidant, 2-4 parts of carbonaceous material; wherein, the antioxidant is a combination of metal silicon powder, silicon carbide micro powder and Si-N-O micro powder.

[0022] The refractory castable for matte launder of the embodiment of the present invention is added with an antioxidant composed of a combination of metal silicon powder, silicon carbide micropowder and Si-N-O micropowder. First of all, under the action of high temperature, the metal silicon powder, silicon carbide micropowder and Si-N-O micropowder can form a continuous glaze layer on the surface of the castable to block pores and coat on the refractory material to prevent the refractory material from being further oxidized. Secondly, each component in the antioxidant is an ultrafine powder. By using the filling effect of the micropowder on the micropores in the matrix of the castable, the density of the castable is improved, the oxidation of the castable by oxygen or oxygen-rich substances is reduced, the density of the matrix is increased, and the solid-phase sintering strength of the castable can be improved earlier and faster, so that the refractory castable for matte launder of nickel matte has a lower porosity, stronger antioxidant and slag erosion resistance. More importantly, and the key innovation point of the present invention is that in the antioxidant, the SiO2 generated after the oxidation of the metal silicon powder and Si-N-O micropowder, and the silica micropowder in the binder react with the alumina micropowder in the matrix to form columnar mullite; at high temperature, the SiO gas phase and SiNO formed by the oxidation of the metal silicon powder and Si-N-O micropowder react with the alumina micropowder in the matrix to form a substitutional solid solution O'-sialon phase; the metal silicon powder reacts with the carbon source in the matrix to form SiC whiskers. The whiskers, columnar crystals and O'-sialon phase formed by the above reactions have a significant strengthening and toughening effect, which can significantly improve the high-temperature strength, thermal shock stability, erosion resistance and penetration resistance of the castable. In addition, the above micropowders have high activity and react with the alumina micropowder in the matrix to form a mullite phase, and the slight volume expansion further fills the pores generated in the castable, improving the antioxidant performance and strength of the castable.

[0023] The refractory castable for matte launder of the embodiment of the present invention uses a higher proportion of silicon carbide compared with the existing trough castable, and the silicon carbide adopts a multi-stage particle size combination of particles, fine powder and micropowder, which can improve the uniformity of the silicon carbide distribution and better exert the performance characteristics of silicon carbide such as non-wetting, antioxidant (forming an oxide film on the surface to slow down continuous oxidation) and high hardness and wear resistance, and can effectively cope with the higher permeability, oxidability and scouring action of nickel matte melt, thereby improving the service life.

[0024] The castable of the present invention is applied to the matte launder of nickel matte, has strong applicability, convenient construction, can produce various special-shaped prefabricated parts or be used for local hot repair and maintenance, and has significant advantages in aspects such as saving resources, reducing costs, improving construction efficiency and improving service life.

[0025] Preferably, its preparation raw materials include the following components in parts by mass: 6 to 10 parts of bauxite particles or their recycled particle materials, 28 to 35 parts of corundum particles or their recycled particle materials, 25 to 30 parts of silicon carbide particles or their recycled particle materials, 1 to 5 parts of corundum fine powder, 6 to 10 parts of silicon carbide fine powder, 6 to 10 parts of alumina fine powder, 3.4 to 7 parts of binder, 5 to 9 parts of antioxidant, and 2 to 3 parts of carbonaceous material.

[0026] Moreover, if the addition amount of the binder is too much, more high-temperature liquid phase will be introduced, reducing the high-temperature strength. If the addition amount of the binder is too little, the curing strength of the castable will be low, which is not conducive to demolding and baking. If the addition amount of the antioxidant is too much, the viscosity of the castable will increase, and the construction performance will decrease significantly. If the addition amount is too little, the oxide film cannot be continuously formed, reducing the antioxidant performance of the castable. Only when the addition amounts of the binder and the antioxidant are appropriate can the castable have good construction performance and service performance. For the refractory castable for low-grade nickel matte launder of the present invention, when the above-preferred mass parts are adopted, the water addition amount of the obtained castable is low, the fluidity is good, which is more conducive to the construction of the castable, promotes the densification of the castable and improves the strength, and the high-temperature strength, thermal shock stability, erosion resistance, and penetration resistance of the castable are better.

[0027] Preferably, the mass ratio of the alumina fine powder to the antioxidant is 1:0.625 to 1.25. On the one hand, the alumina fine powder can react with SiO2 generated after the oxidation of the antioxidant to form columnar mullite. On the other hand, it can react with the metal silicon powder in the unoxidized antioxidant, the SiO gas phase formed by the oxidation of Si-N-O fine powder, and SiNO at high temperature to form a substitutional solid solution O'-sialon phase, thus playing a toughening effect; it can also react with the antioxidant to form a mullite phase, generating a certain volume expansion, filling pores, and improving the performance of the castable. Therefore, the alumina fine powder and the antioxidant need to have an appropriate mass ratio to cooperate to generate an appropriate amount of columnar mullite and O'-sialon phase, and produce an appropriate volume expansion, so that the high-temperature strength, thermal shock stability, erosion resistance, and penetration resistance of the castable are better.

[0028] Preferably, the antioxidant is a combination of metal silicon powder, silicon carbide fine powder, and Si-N-O fine powder with a mass ratio of 2:2 to 4:2 to 4. In the antioxidant, when the mass ratio of the metal silicon powder, silicon carbide fine powder, and Si-N-O fine powder is appropriate, the amount of columnar mullite and O'-sialon phase generated can be appropriate, and an appropriate volume expansion can be produced, so that the high-temperature strength, thermal shock stability, erosion resistance, and penetration resistance of the castable are better. Further preferably, the antioxidant is a combination of metal silicon powder, silicon carbide fine powder, and Si-N-O fine powder with a mass ratio of 2:3:3.

[0029] Preferably, the binder is a mixture of silica powder and aluminate cement with a mass ratio of 1:0.5 - 1.5, or the binder is a mixture of silica powder, Secar-Z, and aluminate cement with a mass ratio of 0.7:2 - 3:0.5 - 1.5, or the binder is a mixture of silica powder, silica sol, and aluminate cement with a mass ratio of 1.5:4 - 6:0.6 - 0.8. Further preferably, the binder is a mixture of silica powder and aluminate cement with a mass ratio of 1:1, or the binder is a mixture of silica powder, Secar-Z, and aluminate cement with a mass ratio of 0.7:2.5:1, or the binder is a mixture of silica powder, silica sol, and aluminate cement with a mass ratio of 1.5:5:0.7.

[0030] For the refractory castable for low-grade nickel matte launder in the embodiment of the present invention, there are three types of binders to choose from, which can be applied to different construction environments and exhibit better performance. The first one is the composite binder of silica powder and aluminate cement; the second one is the composite binder of silica powder, Secar-Z, and aluminate cement; the third one is the composite binder of silica powder, silica sol, and aluminate cement. These three types of binders have the following beneficial effects on the castable: First, when different binders are used in combination, the addition amount of aluminate cement in the castable is reduced, the CaO content is low, the content of low-melting phase generated at high temperature is reduced, it has good high-temperature strength, and the erosion resistance is improved; Second, the castables with the first and second binders can be directly mixed with water during construction and are applicable to cold and hot construction. Among them, the castable with the first binder can generate relatively high strength through natural curing in a cold environment, but it requires a certain curing time. The castable with the second binder can generate strength quickly in a hot environment, shortening the curing time. The castable with the third binder is added with silica sol solution during construction, and no free water is added to the castable, which is beneficial for rapid baking and is especially suitable for casting and ramming construction under hot conditions.

[0031] Preferably, it further includes the following components in mass percentage: Water reducing agent 0.1% - 0.3%, boron carbide 0.2% - 0.8%, explosion-proof agent 0.07% - 0.25%.

[0032] Among them, boron carbide has certain antioxidant properties.

[0033] Preferably, the silicon carbide particles or their recycled particle materials are composed of silicon carbide or its recycled particle materials with a particle size of 1 - 3 mm and silicon carbide or its recycled particle materials with a particle size of 0.1 - 1 mm, mixed in a mass ratio of 10 - 13:14 - 17; the silicon carbide fine powder is composed of 200-mesh silicon carbide fine powder and 325-mesh silicon carbide fine powder, mixed in a mass ratio of 5 - 10:1 - 4; the particle size of the silicon carbide micropowder is 1 - 5 μm.

[0034] For the refractory castable for matte launder of the embodiment of the present invention, silicon carbide adopts a multi-stage particle size matching of particles, fine powder and ultra-fine powder, which improves the uniformity of the silicon carbide distribution, better exerts the performance characteristics of silicon carbide such as non-wetting, oxidation resistance and high hardness wear resistance, and can effectively cope with the high permeability, oxidation and scouring effect of the matte melt, thereby improving the service life.

[0035] Preferably, the particle size of the bauxite particles or their recycled particle materials is 8-15 mm.

[0036] Preferably, the corundum particles or their recycled particle materials include brown corundum particles or their recycled particle materials with a particle size of 5-8 mm, brown corundum particles or their recycled particle materials with a particle size of 3-5 mm, and dense corundum particles or their recycled particle materials with a particle size of 1-3 mm; the mass ratio of the bauxite particles or their recycled particle materials with a particle size of 8-15 mm, brown corundum particles or their recycled particle materials with a particle size of 5-8 mm, brown corundum particles or their recycled particle materials with a particle size of 3-5 mm, and dense corundum particles or their recycled particle materials with a particle size of 1-3 mm is 6-10:12-17:14-17:2-5.

[0037] Preferably, the particle size of the corundum fine powder is 200 mesh.

[0038] Preferably, the particle size of the metallic silicon powder is 3-40 μm; the particle size of the Si-N-O ultra-fine powder is 0.5-20 μm; the particle size of the alumina ultra-fine powder is 2-5 μm. Using the ultra-fine powder with the above particle sizes for each component in the antioxidant can better fill the micropores in the castable matrix, improve the density of the castable, and reduce the oxidation of the castable by oxygen or oxygen-rich substances.

[0039] Preferably, the particle size of the carbonaceous material is 0.001-2 mm.

[0040] Preferably, the particle size of the boron carbide is 325 mesh.

[0041] Preferably, the content of Al2O3 in the bauxite particles is not less than 87 wt%, the content of Fe2O3 is not higher than 1.55%, the porosity is <5.5%, and the bulk density is >3.3 g / cm 3 .

[0042] Preferably, the content of Al2O3 in the recycled bauxite particle material and the recycled corundum particle material is not less than 90 wt%, and the bulk density is ≥3.7 g / cm 3 .

[0043] Preferably, the SiC content in the silicon carbide particles is not less than 92 wt%; more preferably, the SiC content is ≥97 wt%.

[0044] Preferably, the SiC content in the silicon carbide fine powder is not less than 97 wt%.

[0045] Preferably, the SiO2 content in the silica fine powder is not less than 92 wt%; more preferably, the SiO2 content ≥ 95%.

[0046] Preferably, the SiO2 content in the silica sol is 39 wt% - 41 wt%, the pH is 9 - 10.5, and the viscosity is 10 - 20 mPa·s at 25 °C.

[0047] Preferably, the Al2O3 content in the aluminate cement is not less than 70 wt%.

[0048] Preferably, the carbon material is one or a combination of several of spherical pitch, graphite, and carbon black. Further preferably, the carbon material is spherical pitch and carbon black. Among them, the particle size of the spherical pitch is 0.2 - 1 mm, and the melting point is 160 °C. Carbon black can use various existing different types of carbon black, such as: N220, N330, N550, N660, N990, etc. Preferably, N990 carbon black is used.

[0049] Preferably, the water reducer is one or a combination of several of SP610, FS20, FDN, DF401, PC8159, and BC - 2. Preferably, PC8159 water reducer is used.

[0050] Preferably, the particle size of the boron carbide is 325 mesh, and the total boron ≥ 96%.

[0051] The explosion - proof agent is one or a combination of several of metallic aluminum powder and explosion - proof fiber. Preferably, the explosion - proof agent includes 0.05 - 0.15 parts of metallic aluminum powder and 0.02 - 0.1 parts of explosion - proof fiber. Among them, the particle size of the metallic aluminum powder is not more than 100 mesh, and the melting point of the explosion - proof fiber is less than 160 °C.

[0052] Another aspect of the present invention provides a preparation method of the refractory castable for low - nickel matte launder as described above, including the following steps: S1. Mix the raw materials of the antioxidant to obtain an antioxidant mixture; S2. Mix the antioxidant mixture and the binder to obtain a premix; S3. Mix bauxite particles or their recycled particle materials, corundum particles or their recycled particle materials, silicon carbide particles or their recycled particle materials, corundum fine powder, silicon carbide fine powder, alumina fine powder, carbon material, and the premix to obtain the refractory castable for low - nickel matte launder, wherein the silica sol in the binder is added during use.

[0053] In the following examples, the Al2O3 content in the bauxite particles is not less than 87 wt%, the Fe2O3 content is not higher than 1.55%, the porosity < 5.5%, and the bulk density > 3.3 g / cm 3; The content of Al2O3 in bauxite recycled granular material and corundum recycled granular material is not less than 90wt%, and the bulk density ≥ 3.7g / cm 3 ; The SiC content in silicon carbide particles is not less than 92wt%; the SiC content in silicon carbide fine powder is not less than 97wt%; the SiO2 content in silica fume is not less than 92wt%; the SiO2 content in silica sol is 39wt% - 41wt%, at 25°C, the pH is 9 - 10.5, and the viscosity is 10 - 20mpa·s; the Al2O3 content in aluminate cement is not less than 70wt%; the total boron in boron carbide is ≥ 96%.

[0054] Example 1 The refractory castable for low nickel matte launder of this example, its preparation raw materials include the following components in parts by mass: 6 parts of 88 homogenized bauxite particles with a particle size of 8 - 15mm, 14 parts of brown corundum particles with a particle size of 5 - 8mm, 15 parts of brown corundum particles with a particle size of 3 - 5mm, 3 parts of dense corundum particles with a particle size of 1 - 3mm, 2 parts of dense corundum fine powder with a particle size of 200 mesh, 12 parts of 97 silicon carbide particles with a particle size of 1 - 3mm, 17 parts of silicon carbide particles with a particle size of 0.1 - 1mm, 7 parts of silicon carbide fine powder with a particle size of 200 mesh, 2 parts of silicon carbide fine powder with a particle size of 325 mesh, 8 parts of activated alumina micropowder with a particle size of 2 - 5μm, 2 parts of silica fume, 2 parts of aluminate cement, 2 parts of metallic silicon powder with a particle size of 3 - 40μm, 3 parts of 97 silicon carbide micropowder with a particle size of 3μm, 3 parts of Si - N - O micropowder with a particle size of 0.5 - 20μm, 0.5 part of carbon black N990, 2 parts of spherical asphalt with a particle size of 0.2 - 1mm, 0.1 part of metallic aluminum powder with a particle size of 200 mesh, 0.05 part of explosion - proof fiber, 0.2 part of water - reducing agent PC8159, 0.8 part of boron carbide with a particle size of 325 mesh.

[0055] The preparation method of the refractory castable for low nickel matte launder of this example includes the following steps: (1) Prepare each component in the antioxidant according to the required proportion, and mix them evenly using a high - speed planetary mixer to obtain an antioxidant mixture; (2) Mix the antioxidant mixture, binder, metallic aluminum powder, explosion - proof fiber, water - reducing agent, and boron carbide evenly to obtain a premixed small material; (3) Put the granular materials, fine powders, and premixed small materials in the raw materials into a planetary mixer and mix them evenly to obtain the finished castable; (4) When using the finished castable, add 4.5% water, stir well to obtain a wet - mixed material, pour the wet - mixed material into a mold or construction surface, and it can be put into use after curing and baking.

[0056] Example 2 The refractory castable for low nickel matte launder in this example has the same other components and mass fractions of the preparation raw materials as those in Example 1, except that the binder is 2 parts of Secar-Z, 0.7 part of silica fume, and 0.75 part of aluminate cement.

[0057] The preparation method of the refractory castable for low nickel matte launder in this example is the same as that in Example 1.

[0058] Example 3 The refractory castable for low nickel matte launder in this example has the same other components and mass fractions of the preparation raw materials as those in Example 1, except that the binder is 1.5 parts of silica fume, 5 parts of silica sol, and 0.7 part of aluminate cement.

[0059] The preparation method of the refractory castable for low nickel matte launder in this example includes the following steps: (1) Prepare each component in the antioxidant according to the required ratio and mix them evenly using a high-speed planetary mixer to obtain an antioxidant mixture; (2) Mix the antioxidant mixture, binder (except silica sol), metallic aluminum powder, explosion-proof fiber, water reducer, and boron carbide evenly to obtain a premixed small material; (3) Put the granular material, fine powder, and premixed small material in the raw materials into a planetary mixer and mix them evenly to obtain a finished castable; (4) When using the finished castable, add a silica sol solution (concentration of 5%), stir well to obtain a wet-mixed material, pour the wet-mixed material into a mold or construction surface, and it can be put into use after curing and baking.

[0060] Example 4 The refractory castable for low nickel matte launder in this example has the same other components and mass fractions of the preparation raw materials as those in Example 2, except that the bauxite particles with a particle size of 8 - 15 mm, brown fused alumina particles, brown fused alumina particles with a particle size of 5 - 8 mm, and brown fused alumina particles with a particle size of 3 - 5 mm are all replaced with bauxite, brown fused alumina tundish recycling materials with the same particle size and the same mass fraction, and the Al2O3 in the recycling material ≥ 90 wt%, and the bulk density ≥ 3.7 g / cm 3 .

[0061] The preparation method of the refractory castable for low nickel matte launder in this example is the same as that in Example 2.

[0062] Example 5 The refractory castable for low nickel matte launder in this example has the same other components and mass fractions of the preparation raw materials as those in Example 2, except that 5 parts of 200-mesh dense fused alumina are replaced and 0 part of silicon carbide micro powder is replaced.

[0063] The preparation method of the refractory castable for low nickel matte launder in this example is the same as that in Example 2.

[0064] Example 6 For the refractory castable used in the matte launder of this example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that 3 parts of dense corundum with 200 meshes are replaced, and 2 parts of silicon carbide fine powder are replaced.

[0065] The preparation method of the refractory castable used in the matte launder of this example is the same as that in Example 2.

[0066] Example 7 For the refractory castable used in the matte launder of this example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that 1 part of dense corundum with 200 meshes is replaced, and 4 parts of silicon carbide fine powder are replaced.

[0067] The preparation method of the refractory castable used in the matte launder of this example is the same as that in Example 2.

[0068] Example 8 For the refractory castable used in the matte launder of this example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that 4 parts of dense corundum with 200 meshes are replaced, and 0 part of Si-N-O fine powder is replaced.

[0069] The preparation method of the refractory castable used in the matte launder of this example is the same as that in Example 2.

[0070] Example 9 For the refractory castable used in the matte launder of this example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that 2 parts of dense corundum with 200 meshes are replaced, and 2 parts of Si-N-O fine powder are replaced.

[0071] The preparation method of the refractory castable used in the matte launder of this example is the same as that in Example 2.

[0072] Example 10 For the refractory castable used in the matte launder of this example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that 0 part of dense corundum with 200 meshes is replaced, and 4 parts of Si-N-O fine powder are replaced.

[0073] The preparation method of the refractory castable used in the matte launder of this example is the same as that in Example 2.

[0074] Example 11 For the refractory castable used in the matte launder of this example, the preparation raw materials include the following components in mass fractions: 10 parts of 88 homogenized bauxite particles with a particle size of 8 - 15 mm, 12 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 14 parts of brown fused alumina particles with a particle size of 3 - 5 mm, 2 parts of dense corundum particles with a particle size of 1 - 3 mm, 5 parts of dense corundum fine powder with a particle size of 200 mesh, 11 parts of 97 silicon carbide particles with a particle size of 1 - 3 mm, 14 parts of silicon carbide particles with a particle size of 0.1 - 1 mm, 7 parts of silicon carbide fine powder with a particle size of 200 mesh, 3 parts of silicon carbide fine powder with a particle size of 325 mesh, 6 parts of activated alumina micropowder with a particle size of 2 - 5 μm, 2 parts of Secor - Z, 0.7 part of silica micropowder, 0.7 part of aluminate cement, 2 parts of metallic silicon powder with a particle size of 3 - 40 μm, 3 parts of 97 silicon carbide micropowder with a particle size of 3 μm, 3 parts of Si - N - O micropowder with a particle size of 0.5 - 20 μm, 1 part of carbon black N990, 1 part of spherical pitch with a particle size of 0.2 - 1 mm, 0.05 part of metallic aluminum powder with a particle size of 200 mesh, 0.02 part of explosion - proof fiber, 0.3 part of water - reducing agent PC8159, 0.2 part of boron carbide with a particle size of 325 mesh.

[0075] The preparation method of the refractory castable for low - nickel matte launder described in this example is the same as that in Example 2.

[0076] Example 12 For the refractory castable for low - nickel matte launder in this example, its preparation raw materials include the following components in parts by mass: 6 parts of 88 homogenized bauxite particles with a particle size of 8 - 15 mm, 15 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 15 parts of brown fused alumina particles with a particle size of 3 - 5 mm, 5 parts of dense corundum particles with a particle size of 1 - 3 mm, 1 part of dense corundum fine powder with a particle size of 200 mesh, 13 parts of 97 silicon carbide particles with a particle size of 1 - 3 mm, 17 parts of silicon carbide particles with a particle size of 0.1 - 1 mm, 5 parts of silicon carbide fine powder with a particle size of 200 mesh, 1 part of silicon carbide fine powder with a particle size of 325 mesh, 8 parts of activated alumina micropowder with a particle size of 2 - 5 μm, 3 parts of Secor - Z, 2 parts of silica micropowder, 2 parts of aluminate cement, 2 parts of metallic silicon powder with a particle size of 3 - 40 μm, 3 parts of 97 silicon carbide micropowder with a particle size of 3 μm, 3 parts of Si - N - O micropowder with a particle size of 0.5 - 20 μm, 1 part of carbon black N990, 2 parts of spherical pitch with a particle size of 0.2 - 1 mm, 0.15 part of metallic aluminum powder with a particle size of 200 mesh, 0.1 part of explosion - proof fiber, 0.1 part of water - reducing agent PC8159, 0.8 part of boron carbide with a particle size of 325 mesh.

[0077] The preparation method of the refractory castable for low - nickel matte launder described in this example is the same as that in Example 2.

[0078] Example 13 For the refractory castable for low - nickel matte launder in this example, its preparation raw materials include the following components in parts by mass: 15 parts of 88 homogenized bauxite particles with a particle size of 8 - 15 mm, 10 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 13 parts of brown fused alumina particles with a particle size of 3 - 5 mm, 2 parts of dense corundum particles with a particle size of 1 - 3 mm, 10 parts of dense corundum fine powder with a particle size of 200 mesh, 8 parts of 97 silicon carbide particles with a particle size of 1 - 3 mm, 12 parts of silicon carbide particles with a particle size of 0.1 - 1 mm, 10 parts of silicon carbide fine powder with a particle size of 200 mesh, 5 parts of silicon carbide fine powder with a particle size of 325 mesh, 4 parts of activated alumina micropowder with a particle size of 2 - 5 μm, 2 parts of Secor - Z, 0.7 part of silica micropowder, 0.7 part of aluminate cement, 0.75 part of metallic silicon powder with a particle size of 3 - 40 μm, 1.125 parts of 97 silicon carbide micropowder with a particle size of 3 μm, 1.125 parts of Si - N - O micropowder with a particle size of 0.5 - 20 μm, 1 part of carbon black N990, 1 part of spherical pitch with a particle size of 0.2 - 1 mm, 0.1 part of metallic aluminum powder with a particle size of 200 mesh, 0.05 part of explosion - proof fiber, 0.2 part of water - reducing agent PC8159, 0.8 part of boron carbide with a particle size of 325 mesh.

[0079] The preparation method of the refractory castable for low - nickel matte launder described in this example is the same as that in Example 2.

[0080] Example 14 The refractory castable for low - nickel matte launder in this example, its preparation raw materials include the following components in parts by mass: 6 parts of 88 homogenized bauxite particles with a particle size of 8 - 15 mm, 16 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 17 parts of brown fused alumina particles with a particle size of 3 - 5 mm, 7 parts of dense corundum particles with a particle size of 1 - 3 mm, 1 part of dense corundum fine powder with a particle size of 200 mesh, 13 parts of 97 silicon carbide particles with a particle size of 1 - 3 mm, 17 parts of silicon carbide particles with a particle size of 0.1 - 1 mm, 4 parts of silicon carbide fine powder with a particle size of 200 mesh, 1 part of silicon carbide fine powder with a particle size of 325 mesh, 8 parts of activated alumina micropowder with a particle size of 2 - 5 μm, 4 parts of Secor - Z, 3 parts of silica micropowder, 3 parts of aluminate cement, 2.5 parts of metallic silicon powder with a particle size of 3 - 40 μm, 3.75 parts of 97 silicon carbide micropowder with a particle size of 3 μm, 3.75 parts of Si - N - O micropowder with a particle size of 0.5 - 20 μm, 2 parts of carbon black N990, 2 parts of spherical pitch with a particle size of 0.2 - 1 mm, 0.1 part of metallic aluminum powder with a particle size of 200 mesh, 0.05 part of explosion - proof fiber, 0.2 part of water - reducing agent PC8159, 0.8 part of boron carbide with a particle size of 325 mesh.

[0081] The preparation method of the refractory castable for low - nickel matte launder described in this example is the same as that in Example 2.

[0082] Example 15 The refractory castable for matte launder in this example has the same other components and their amounts in the preparation raw materials as those in Example 2. The difference lies in the antioxidant, where there are 2.67 parts of metallic silicon powder, 2.67 parts of 97 silicon carbide micropowder with a particle size of 3 μm, and 2.67 parts of Si-N-O micropowder with a particle size of 0.5 - 20 μm. That is, the mass ratio of metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder is 1:1:1.

[0083] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0084] Example 16 The refractory castable for matte launder in this example has the same other components and their amounts in the preparation raw materials as those in Example 2. The difference lies in the antioxidant, where there are 1.6 parts of metallic silicon powder, 3.2 parts of 97 silicon carbide micropowder with a particle size of 3 μm, and 3.2 parts of Si-N-O micropowder with a particle size of 0.5 - 20 μm. That is, the mass ratio of metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder is 1:2:2.

[0085] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0086] Example 17 The refractory castable for matte launder in this example has the same other components and their amounts in the preparation raw materials as those in Example 2. The difference lies in the antioxidant, where there are 3 parts of metallic silicon powder, 2.5 parts of 97 silicon carbide micropowder with a particle size of 3 μm, and 2.5 parts of Si-N-O micropowder with a particle size of 0.5 - 20 μm. That is, the mass ratio of metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder is 1:0.83:0.83.

[0087] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0088] Example 18 The refractory castable for matte launder in this example has the same other components and their amounts in the preparation raw materials as those in Example 2. The difference lies in the antioxidant, where there is 1 part of metallic silicon powder, 3.5 parts of 97 silicon carbide micropowder with a particle size of 3 μm, and 3.5 parts of Si-N-O micropowder with a particle size of 0.5 - 20 μm. That is, the mass ratio of metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder is 1:3.5:3.5.

[0089] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0090] Example 19 The refractory castable for matte launder in this example has the same other components and parts by weight of the preparation raw materials as those in Example 2, with the differences being: the alumina micropowder is 9.6 parts; in the antioxidant, the metallic silicon powder is 1.5 parts, the 97 silicon carbide micropowder with a particle size of 3 μm is 2.25 parts, and the Si-N-O micropowder with a particle size of 0.5 - 20 μm is 2.25 parts. That is, the mass ratio of the metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder remains unchanged, and the mass ratio of the alumina micropowder to the antioxidant is 1:0.625.

[0091] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0092] Example 20 The refractory castable for matte launder in this example has the same other components and parts by weight of the preparation raw materials as those in Example 2, with the differences being: the alumina micropowder is 7.1 parts; in the antioxidant, the metallic silicon powder is 2.2 parts, the 97 silicon carbide micropowder with a particle size of 3 μm is 3.3 parts, and the Si-N-O micropowder with a particle size of 0.5 - 20 μm is 3.3 parts. That is, the mass ratio of the metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder remains unchanged, and the mass ratio of the alumina micropowder to the antioxidant is 1:1.24.

[0093] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0094] Example 21 The refractory castable for matte launder in this example has the same other components and parts by weight of the preparation raw materials as those in Example 2, with the differences being: the alumina micropowder is 10 parts; in the antioxidant, the metallic silicon powder is 1.4 parts, the 97 silicon carbide micropowder with a particle size of 3 μm is 2.1 parts, and the Si-N-O micropowder with a particle size of 0.5 - 20 μm is 2.1 parts. That is, the mass ratio of the metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder remains unchanged, and the mass ratio of the alumina micropowder to the antioxidant is 1:0.56.

[0095] The preparation method of the refractory castable for matte launder described in this example is the same as that in Example 2.

[0096] Example 22 The refractory castable for matte launder in this example has the same other components and parts by weight of the preparation raw materials as those in Example 2, with the differences being: the alumina micropowder is 6 parts; in the antioxidant, the metallic silicon powder is 2.5 parts, the 97 silicon carbide micropowder with a particle size of 3 μm is 3.75 parts, and the Si-N-O micropowder with a particle size of 0.5 - 20 μm is 3.75 parts. That is, the mass ratio of the metallic silicon powder, silicon carbide micropowder, and Si-N-O micropowder remains unchanged, and the mass ratio of the alumina micropowder to the antioxidant is 1:1.67.

[0097] Comparative Example 1 For the refractory castable used in the matte launder of this comparative example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that the 88 homogenized bauxite particles with a particle size of 8 - 15 mm are replaced by brown fused alumina with a particle size of 8 - 15 mm.

[0098] The preparation method of the refractory castable used in the matte launder of this comparative example is the same as that in Example 2.

[0099] Comparative Example 2 For the refractory castable used in the matte launder of this comparative example, the other components and their mass fractions of the preparation raw materials are the same as those in Example 2, except that the brown fused alumina and dense fused alumina particles are both replaced by homogenized bauxite particles, that is: 14 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 15 parts of brown fused alumina particles with a particle size of 3 - 5 mm, and 3 parts of dense fused alumina particles with a particle size of 1 - 3 mm are replaced by 14 parts of homogenized bauxite particles with a particle size of 5 - 8 mm, 15 parts of homogenized bauxite particles with a particle size of 3 - 5 mm, and 3 parts of homogenized bauxite particles with a particle size of 1 - 3 mm.

[0100] Comparative Example 3 For the refractory castable used in the matte launder of this comparative example, in the preparation raw materials, the addition amounts of alumina micro - powder, binder, antioxidant, carbonaceous material, metallic aluminum, explosion - proof fiber, water - reducing agent, and boron carbide are the same as those in Example 2, except that the amounts of bauxite, corundum, and silicon carbide are adjusted so that the total amount of silicon carbide particles and fine powder is 22 parts.

[0101] In this example, in the preparation raw materials, there are 6 parts of 88 homogenized bauxite particles with a particle size of 8 - 15 mm, 14 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 15 parts of brown fused alumina particles with a particle size of 3 - 5 mm, 15 parts of dense fused alumina particles with a particle size of 1 - 3 mm, 4 parts of dense fused alumina particles with a particle size of 0.1 - 1 mm, 2 parts of dense fused alumina fine powder with a particle size of 200 mesh, 0 parts of 97 silicon carbide particles with a particle size of 1 - 3 mm, 13 parts of silicon carbide particles with a particle size of 0.1 - 1 mm, 7 parts of silicon carbide fine powder with a particle size of 200 mesh, and 2 parts of silicon carbide fine powder with a particle size of 325 mesh.

[0102] Comparative Example 4 For the refractory castable used in the matte launder of this comparative example, in the preparation raw materials, the addition amounts of alumina micro - powder, binder, antioxidant, carbonaceous material, metallic aluminum, explosion - proof fiber, water - reducing agent, and boron carbide are the same as those in Example 2, except that the amounts of bauxite, corundum, and silicon carbide are adjusted so that the total amount of silicon carbide particles and fine powder is 43 parts.

[0103] In this embodiment, among the preparation raw materials, there are 6 parts of homogenized bauxite particles with a particle size of 8 - 15 mm, 14 parts of brown fused alumina particles with a particle size of 5 - 8 mm, 15 parts of brown fused alumina particles with a particle size of 3 - 5 mm, 0 parts of dense corundum particles with a particle size of 1 - 3 mm, 0 parts of dense corundum particles with a particle size of 0.1 - 1 mm, 0 parts of dense corundum fine powder with a particle size of 200 mesh, 15 parts of 97 silicon carbide particles with a particle size of 1 - 3 mm, 17 parts of silicon carbide particles with a particle size of 0.1 - 1 mm, 9 parts of silicon carbide fine powder with a particle size of 200 mesh, and 2 parts of silicon carbide fine powder with a particle size of 325 mesh.

[0104] Comparative Example 5 For the refractory castable for low - nickel matte launder in this comparative example, among the preparation raw materials, the other components and their parts are the same as those in Example 2, with the difference that the alumina micro - powder is adjusted to 8.75 parts and the aluminate cement is 0 part.

[0105] Comparative Example 6 For the refractory castable for low - nickel matte launder in this comparative example, among the preparation raw materials, the other components and their parts are the same as those in Example 3, with the difference that the alumina micro - powder is adjusted to 6.5 parts and the silicon micro - powder in the binder is adjusted to 3 parts.

[0106] Comparative Example 7 For the refractory castable for low - nickel matte launder in this comparative example, among the preparation raw materials, the other components and their parts are the same as those in Example 3, with the difference that the alumina micro - powder is adjusted to 7.7 parts and the aluminate cement in the binder is adjusted to 1 part.

[0107] The hardening time, strength performance, oxidation performance, and erosion resistance of the refractory castables for low - nickel matte launder in the above - mentioned examples and comparative examples were tested. Among them, the oxidation performance was tested by the proportion of the area of the oxidized region in the cross - section, and the erosion resistance was tested by the static crucible method. The test results are shown in Table 1 below.

[0108] Table 1

[0109] As can be seen from the data in Table 1, compared with Examples 1, 2, and 3, the refractory castables for matte nickel slags using different binders exhibit different characteristics. In Example 1, conventional cement and silica fine powder are used for binding, which has better normal temperature strength than Examples 2 and 3, but lower high temperature strength, oxidation rate, and erosion rate. Under cold-state construction conditions, after oxidation and baking processes, Example 1 can meet the service conditions of matte nickel slags. Example 2 has a longer hardening time, but higher high temperature strength, oxidation rate, and erosion rate than Example 1. After construction is completed, it can be quickly baked to increase strength, and is more suitable for construction conditions with a certain temperature, and has a better service effect. Compared with Examples 1 and 2, Example 3 has low normal temperature strength and short construction time, but has the best high temperature strength, oxidation resistance, and erosion resistance. It is more suitable for hot-state construction and is carried out by casting or ramming. It generates strength quickly, can be put into use in a short time, significantly shortens the construction time, and has a relatively long service life.

[0110] In Comparative Example 1, the homogenized bauxite in the aggregate was replaced with brown fused alumina. In Example 4, the granular materials were all replaced with tundish reclaim. Compared with Example 2 where part of the aggregate used bauxite, the various properties of Comparative Example 1 and Example 4 were slightly lower than those of Example 2, but could meet the usage requirements. However, in Comparative Example 1, the price of brown fused alumina is usually higher than that of homogenized bauxite. Therefore, the cost is higher, but the performance is slightly worse. Although the performance indexes of Example 4 are slightly worse, the average price of brown fused alumina was 5,250 yuan / ton and the price of the reclaim was 3,850 yuan / ton during the same period. It can be seen that using tundish reclaim slightly reduces the performance, but on the basis of ensuring the performance of the castable, it significantly reduces the material cost of the castable, promotes the recycling of resources, and reduces waste emissions.

[0111] Compared with Example 2, Examples 5, 6, and 7 differ in the amount of silicon carbide fine powder added. In Example 2, adding 3 parts of 97 silicon carbide fine powder has the best strength, oxidation resistance, and erosion resistance. When the addition amount is reduced, the filling in the castable matrix by the fine powder is insufficient, the porosity of the castable is high, and the oxidation resistance and erosion resistance are slightly worse. When the addition amount is increased, the viscosity of the castable increases and the fluidity becomes worse, resulting in a significant increase in pores in the castable matrix, and the oxidation resistance and erosion resistance deteriorate severely. This shows that when the mass fractions of other components are the same, the addition amount of 97 silicon carbide fine powder in Example 2 is preferred and plays a role in improving the performance indexes of the castable.

[0112] In Examples 8, 9, and 10, compared with Example 2, the addition amount of Si-N-O fine powder is different. As the mass fraction of Si-N-O fine powder added to the antioxidant increases, the oxidation rate of the castable gradually decreases, and the erosion rate first decreases and then increases. When the addition amount of Si-N-O fine powder reaches 3 parts, the erosion rate of the castable reaches the lowest, and the mechanical properties reach the best value. Excessive Si-N-O fine powder will affect the fluidity of the castable, increase the proportion of liquid phase in the matrix, and lead to a decline in mechanical properties and erosion resistance. Therefore, with the mass fractions of other components in the raw materials remaining unchanged, appropriate addition of Si-N-O fine powder can make the comprehensive performance of the castable better.

[0113] In Examples 2, 11, 12, 13, and 14, the difference is that the mass fractions of each component are different. Among them, the mass fractions of each component of the raw materials in Examples 2, 11, and 12 are within the preferred range, and their comprehensive properties such as mechanical properties, erosion resistance, and oxidation resistance are superior to those in Examples 13 and 14.

[0114] In Examples 2, 15, 16, 17, and 18, the difference is that in the antioxidant, the proportions of metallic silicon powder, silicon carbide fine powder, and Si-N-O fine powder are different. Among them, the proportions of metallic silicon powder, silicon carbide fine powder, and Si-N-O fine powder in Examples 2, 15, and 16 are within the preferred range, and their comprehensive properties such as mechanical properties, erosion resistance, and oxidation resistance are superior to those in Examples 17 and 18.

[0115] In Examples 2, 19, 20, 21, and 22, the difference is that the mass ratio of alumina fine powder to antioxidant is different. Among them, the mass ratios of alumina fine powder to antioxidant in Examples 2, 19, and 20 are within the preferred range, and their comprehensive properties such as mechanical properties, erosion resistance, and oxidation resistance are superior to those in Examples 21 and 22.

[0116] Compared with Example 2, in Comparative Example 2, all brown fused alumina and dense fused alumina in the particles are replaced with 88 homogenized bauxite. The performance indicators show that the hardening time is shortened, the strength is increased, and the strengthening rate and erosion rate are increased. This is because 88 homogenized bauxite has a high water absorption rate, is easy to sinter, and has a high porosity, so the hardening time is short. 88 homogenized bauxite has a high impurity content, and the calcination temperature is low during the production process of bauxite raw materials, making it easier to sinter at high temperatures. Therefore, the strength of the specimen is increased at high temperatures. However, 88 homogenized bauxite has a high porosity, making it easier for oxidation and slag penetration erosion to occur in the specimen, resulting in an increase in the oxidation rate and erosion rate.

[0117] In Comparative Example 3, Example 2, and Comparative Example 4, the total number of parts of silicon carbide particles and fine powder corresponds to 22 parts, 38 parts, and 43 parts respectively. It can be seen from the experimental results that as the addition ratio of silicon carbide increases, the hardening time is prolonged, the strength decreases, and the oxidation rate and erosion rate show an increasing trend. Appropriate addition amount of silicon carbide can make the comprehensive performance of the castable better.

[0118] Compared with Example 2, in Comparative Example 5, cement was removed, resulting in a significant increase in the specimen hardening time, a significant decrease in strength, and the inability to demold the specimen for a long time. After demolding, due to low strength, microcracks occurred during the baking process, leading to an increase in the erosion rate. Therefore, it is necessary to add a small amount of cement in Example 2 to ensure the workability of the castable, with an appropriate hardening time and demolding strength, and no cracks or bulging of the cast body during high-temperature baking.

[0119] Compared with Example 3, in Comparative Example 6, the addition amount of silica fume was increased. From the test results, it can be seen that the addition of silica fume disrupted the equilibrium system of the silica sol, causing the specimen to react rapidly, lose fluidity, resulting in low strength, high porosity, and a significant increase in the oxidation rate and erosion rate. Therefore, in the silica sol system, an appropriate ratio of silica fume, silica sol, and cement can make the castable have better workability, while also filling the pores, improving strength and erosion resistance.

[0120] Compared with Example 3, in Comparative Example 7, the amount of aluminate cement added was different. Adding an appropriate amount of aluminate cement can promote the curing reaction of the silica sol. If the addition amount is small, the castable cannot harden for a long time, with low strength and unable to demold. However, if too much cement is added, it will cause the castable to quickly lose fluidity, unable to meet the construction requirements, unable to prepare specimens, and not having workability.

[0121] Obviously, the above examples are only for clear illustration and not a limitation on the implementation methods. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all implementation methods here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. A refractory castable for a matte launder, characterized in that, The raw materials for its preparation include the following components in parts by mass: 6 - 15 parts of bauxite particles or their recycled particle materials, 25 - 40 parts of corundum particles or their recycled particle materials, 20 - 30 parts of silicon carbide particles or their recycled particle materials, 1 - 10 parts of corundum fine powder, 5 - 15 parts of silicon carbide fine powder, 4 - 10 parts of alumina fine powder, 3.4 - 10 parts of binder, 3 - 10 parts of antioxidant, 2 - 4 parts of carbonaceous material; wherein, the antioxidant is a combination of metallic silicon powder, silicon carbide fine powder and Si - N - O fine powder with a mass ratio of 2:2 - 4:2 - 4.

2. The refractory castable for matte launder according to claim 1, wherein, The raw materials for its preparation include the following components in parts by mass: 6 - 10 parts of bauxite particles or their recycled particle materials, 28 - 35 parts of corundum particles or their recycled particle materials, 25 - 30 parts of silicon carbide particles or their recycled particle materials, 1 - 5 parts of corundum fine powder, 6 - 10 parts of silicon carbide fine powder, 6 - 10 parts of alumina fine powder, 3.4 - 7 parts of binder, 5 - 9 parts of antioxidant, 2 - 3 parts of carbonaceous material.

3. The refractory castable for matte launder according to claim 1, characterized in that: The mass ratio of alumina fine powder to antioxidant is 1:0.625 - 1.

25.

4. The refractory castable for matte launder according to claim 1, characterized in that: The binder is a mixture of silica fine powder and aluminate cement with a mass ratio of 1:0.5 - 1.5, or the binder is a mixture of silica fine powder, Secar - Z and aluminate cement with a mass ratio of 0.7:2 - 3:0.5 - 1.5, or the binder is a mixture of silica fine powder, silica sol and aluminate cement with a mass ratio of 1.5:4 - 6:0.6 - 0.

8.

5. The refractory castable for matte launder according to claim 1, characterized in that, It further includes the following components in parts by mass: 0.1 - 0.3 part of water - reducing agent, 0.2 - 0.8 part of boron carbide, 0.07 - 0.25 part of explosion - proof agent.

6. The refractory castable for matte launder according to claim 5, characterized in that: The silicon carbide particles or their recycled particle materials are composed of silicon carbide or its recycled particle materials with a particle size of 1 - 3 mm and silicon carbide or its recycled particle materials with a particle size of 0.1 - 1 mm, mixed in a mass ratio of 10 - 13:14 - 17; The silicon carbide fine powder is composed of 200 - mesh silicon carbide fine powder and 325 - mesh silicon carbide fine powder, mixed in a mass ratio of 5 - 10:1 - 4; The particle size of the silicon carbide fine powder is 1 - 5 μm; The corundum particles or their recycled particle materials include brown corundum particles or their recycled particle materials with a particle size of 5 - 8 mm, brown corundum particles or their recycled particle materials with a particle size of 3 - 5 mm, dense corundum particles or their recycled particle materials with a particle size of 1 - 3 mm; the mass ratio of bauxite particles or their recycled particle materials with a particle size of 8 - 15 mm, brown corundum particles or their recycled particle materials with a particle size of 5 - 8 mm, brown corundum particles or their recycled particle materials with a particle size of 3 - 5 mm, dense corundum particles or their recycled particle materials with a particle size of 1 - 3 mm is 6 - 10:12 - 17:14 - 17:2 - 5; The particle size of the corundum fine powder is 200 mesh; The particle size of the bauxite particles or their recycled particle materials is 8 - 15 mm; The particle size of the metallic silicon powder is 3 - 40 μm; The particle size of the Si-N-O fine powder is 0.5 - 20 μm; The particle size of the alumina fine powder is 2 - 5 μm; The particle size of the carbonaceous material is 0.001 - 2 mm; The particle size of the boron carbide is 325 mesh.

7. The refractory castable for matte launder according to claim 5, wherein: The content of Al2O3 in the bauxite particles is not less than 87wt%, the content of Fe2O3 is not higher than 1.55%, the porosity is <5.5%, and the bulk density is >3.3g / cm 3 ; The content of Al2O3 in bauxite recycled granular material and corundum recycled granular material is not less than 90 wt%, and the bulk density ≥ 3.7 g / cm 3 ; The SiC content in the silicon carbide particles is not less than 92 wt%; The SiC content in the silicon carbide fine powder is not less than 97 wt%; The SiO2 content in the silica fine powder is not less than 92 wt%; The SiO2 content in the silica sol is 39 wt% - 41 wt%, at 25 °C, the pH is 9 - 10.5, and the viscosity is 10 - 20 mPa·s; The Al2O3 content in the aluminate cement is not less than 70 wt%.

8. The refractory castable for matte launder according to claim 5, wherein: The carbonaceous material is a combination of one or more of spherical pitch, graphite, and carbon black; The water reducing agent is a combination of one or more of SP610, FS20, FDN, DF401, PC8159, and BC-2; The explosion-proof agent is a combination of one or more of metallic aluminum powder and explosion-proof fiber.

9. A preparation method of the refractory castable for the matte launder as described in any one of claims 1-8, characterized in that, It includes the following steps: S1. Mix the raw materials of the antioxidant to obtain an antioxidant mixture; S2. Mix the antioxidant mixture and the binder to obtain a premix; S3. Mix bauxite particles or their recycled particle materials, corundum particles or their recycled particle materials, silicon carbide particles or their recycled particle materials, corundum fine powder, silicon carbide fine powder, alumina fine powder, carbonaceous material, and the premix to obtain the refractory castable for matte launder, wherein the silica sol in the binder is added during use.

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