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CN-119430889-B - Microporous mullite-silicon carbide reinforced blast furnace tapping main channel castable

CN119430889BCN 119430889 BCN119430889 BCN 119430889BCN-119430889-B

Abstract

The invention discloses a microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable, belongs to the technical field of refractory materials, and is used for solving the technical problems that the fluidity of the castable and the high temperature resistance of a casting product in the prior art are to be improved; the casting material comprises, by weight, 50-54 parts of fused brown corundum, 3-5 parts of fused brown corundum powder, 4-6 parts of white corundum powder, 16-18 parts of silicon carbide, 6-8 parts of alumina micropowder, 0.2-0.6 part of boron carbide, 1-3 parts of modified graphite, 2-3 parts of silica micropowder, 1-3 parts of elemental silicon powder, 2-4 parts of modified silica sol and 0.2-0.5 part of a water reducer, wherein the components are mutually matched, so that the fluidity of the casting material is improved and the high temperature resistance of a casting product is improved.

Inventors

  • YUAN GENFANG

Assignees

  • 宜兴市中电耐磨耐火科技有限公司

Dates

Publication Date
20260508
Application Date
20241125

Claims (6)

  1. 1. The microporous mullite-silicon carbide reinforced blast furnace tapping main channel castable is characterized by comprising, by weight, 50-54 parts of fused brown corundum, 3-5 parts of fused brown corundum powder, 4-6 parts of white corundum powder, 16-18 parts of silicon carbide, 6-8 parts of alumina micropowder, 0.2-0.6 part of boron carbide, 1-3 parts of modified graphite, 2-3 parts of silica micropowder, 1-3 parts of elemental silicon powder, 120-140 parts of modified silica sol and 0.2-0.5 part of water reducer; The modified silica sol is obtained by processing the following steps: a1, adding a silane coupling agent, an ethanol solvent and deionized water into a magnetic stirrer for stirring, increasing the stirring temperature of the magnetic stirrer to 50-60 ℃, and carrying out heat preservation reaction for 1-2h to obtain a preform; A2, adding the preform and the silica sol into a grinding and dispersing mixer for stirring, adding an acetic acid solution for regulating the pH value of the system to 5-6, increasing the temperature of the grinding and dispersing mixer to 50-60 ℃, and carrying out heat preservation reaction for 1-2h to obtain modified silica sol; The modified graphite is obtained by processing the following steps: b1, washing the flake graphite to be neutral by deionized water, putting the flake graphite into a vacuum drying oven for drying to constant weight, and grinding and screening the flake graphite to obtain pretreated flake graphite; b2, preparing a modified flake graphite precursor by post-treatment, wherein the pre-treatment flake graphite, metal silicon, silicon carbide and organic polymer binder form mixed mucilage; And B3, adding the modified flake graphite precursor and the surfactant KS1055 into a reaction kettle for stirring, setting the stirring speed to be 550-600r/min, aging for 3-5h, and performing post-treatment to obtain the modified graphite.
  2. 2. The microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable according to claim 1, wherein the grain size of the fused brown alumina is 5-8mm, the grain size of the fused brown alumina powder is 0.5-1mm, the grain size of the white corundum powder is 0.001-0.044mm, the grain size of the silicon carbide is 1-3mm, the grain size of the alumina micropowder is 0.5-1 μm, the grain size of the boron carbide is 1-3mm, the grain size of the modified graphite is 200 meshes, the grain size of the silica micropowder is 200 meshes, the grain size of the elemental silicon powder is 0.001-0.037mm, and the water reducer is polycarboxylate.
  3. 3. The microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable based on the invention of claim 1 is characterized in that the silane coupling agent is methyltrimethoxysilane, the dosage ratio of the silane coupling agent, ethanol solvent and deionized water is 10-20g:60-100mL:20-60mL, the rotating speed of a magnetic stirrer is 650r/min, the silica sol is an alkaline silica sol binder, the particle size of the silica sol binder is 10-20nm, the pH=9.5, and the density is The rotating speed of the grinding dispersion stirrer is 400r/min, the dosage ratio of the preform to the silica sol is 9-10mL:10-11mL, and the concentration of the acetic acid solution is 0.1moL/L.
  4. 4. The microporous mullite-silicon carbide reinforced blast furnace tapping main channel castable according to claim 1, wherein in step B1, the particle size of the crystalline flake graphite is 80-100 mesh, and the vacuum drying oven temperature is 100-110 ℃.
  5. 5. The microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable is characterized in that in the step B2, the silicon carbide granularity is 2-5 mu m, the organic polymer binder is one of epoxy resin and acrylic resin, the usage ratio of the pretreated crystalline flake graphite to the metal silicon to the silicon carbide to the organic polymer binder is 12-14g:1-2 g:50-60mL, and the post-treatment operation comprises the steps of placing mixed mucus into a muffle furnace, raising the temperature of the muffle furnace to 500-800 ℃, carrying out heat preservation for 5-6h, cooling, discharging, crushing, and sieving with a 200-mesh sieve to obtain the modified crystalline flake graphite precursor.
  6. 6. The microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable is characterized in that in the step B3, the dosage ratio of the modified crystalline flake graphite precursor to the surfactant KS1055 is 10-15g:50-60mL, the post-treatment method comprises the steps of filtering after ageing, washing a filter cake with purified water to be neutral, pumping, transferring the filter cake into a drying oven with the temperature of 80-90 ℃, drying in vacuum to constant weight, crushing, and sieving with a 200-mesh screen to obtain the modified graphite.

Description

Microporous mullite-silicon carbide reinforced blast furnace tapping main channel castable Technical Field The invention relates to the technical field of refractory materials, in particular to a microporous mullite-silicon carbide reinforced blast furnace tapping main channel castable. Background The main iron runner of the blast furnace tapping hole is a channel for guiding high-temperature molten iron and slag, the main iron runner has the function of separating the molten iron from slag, slag in the runner enters the slag tapping runner from the top of the skimming machine lintel, and the molten iron flows through the molten iron channel at the bottom of the skimming machine lintel to realize the separation of the iron and the slag; the iron runner castable is used as a refractory material of the lining of the iron runner, is subjected to high-temperature scouring and chemical erosion of molten iron and slag in the use process, and is subjected to repeated cold and hot alternating action for a long time, so that the iron runner is easy to crack and peel, and the reasons for the phenomenon are mainly that the strength of the material is low, the oxidation resistance is poor and the like, so that the service life of the iron runner is directly determined by the performance of the material, the production capacity and the efficiency of a blast furnace are further determined, and the iron runner of the blast furnace is one of key refractory materials affecting the production of the blast furnace. In the blast furnace ironmaking process, along with the formation of slag, the slag is an alkaline oxide which is extremely easy to react with the refractory material of the iron runner to form a liquid phase, so that the erosion resistance of the main iron runner material is weakened, the erosion is more serious, in order to improve the slag erosion resistance of the refractory material for the iron runner, a carbon material is usually added into the main runner castable, and calcium aluminate cement is used as a binding agent, although the carbon material has the properties of high heat conductivity and low thermal expansion coefficient, the oxidation resistance is poor, and the non-wettability of water to the surface of graphite is extremely poor, so that the dispersibility of graphite in the water is extremely poor, thus affecting the important construction property of the fluidity of the castable, while calcium aluminate cement is used as the castable of the binding agent, a certain amount of CaO is introduced to form a low-melting material in the high-temperature use process, so that the service life of the castable material is influenced, and the chemical erosion resistance, oxidation resistance and fluidity of the high-temperature slag are required to be further improved. In view of the technical drawbacks of this aspect, a solution is now proposed. Disclosure of Invention The invention aims to provide a microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable, which is used for solving the technical problems that the fluidity of the castable and the high temperature resistance of a cast product in the prior art are to be improved. The invention aims at solving the problems that the microporous mullite-silicon carbide reinforced blast furnace tapping main channel castable comprises, by weight, 50-54 parts of fused brown corundum, 3-5 parts of fused brown corundum powder, 4-6 parts of white corundum powder, 16-18 parts of silicon carbide, 6-8 parts of alumina micro powder, 0.2-0.6 part of boron carbide, 1-3 parts of modified graphite, 2-3 parts of silicon dioxide micro powder, 1-3 parts of simple substance silicon powder, 120-140 parts of modified silica sol and 0.2-0.5 part of water reducer. Further, the microporous mullite-silicon carbide reinforced blast furnace tapping main runner castable is characterized in that the grain size of the fused brown corundum is 5-8mm, the grain size of the fused brown corundum powder is 0.5-1mm, the grain size of the white corundum powder is 0.001-0.044mm, the grain size of the silicon carbide is 1-3mm, the grain size of the alumina micro powder is 0.5-1 mu m, the grain size of the boron carbide is 1-3mm, the grain size of the modified graphite is 200 meshes, the grain size of the silicon dioxide micro powder is 200 meshes, the grain size of the simple substance silicon powder is 0.001-0.037mm, and the water reducer is polycarboxylate. The reaction mechanism of the boron carbide is as follows: The more the addition amount of B 4 C fine powder is increased, the more the reserved C is, the more the amount of beta-SiC generated during reaction is increased, and correspondingly, the higher the high-temperature flexural strength is, the silicate glass phase containing boron is easy to generate in the heat treatment process, the surface is easier to form an anti-oxidation film, B 4 C can oxidize C and Si before C and Si, the oxidation reaction of