774 results about "Mullite" patented technology

The invention relates to the technical field of ceramic clay, in particular to wear-resistant ceramic clay and a preparation method thereof.The wear-resistant ceramic clay is prepared from, by weight, 35-40 parts of kieselguhr, 15-20 parts of silicon carbide, 8-12 parts of modifier based on mullite modification, 5-8 parts of modified cordierite agent, 4-7 parts of aluminum oxide, 4-7 parts of calcined talc, 3-5 parts of potassium feldspar and 30-35 parts of water. According to the wear-resistant ceramic clay disclosed by the invention, the diatomite and the silicon carbide are matched with the aluminum oxide, the calcined talc and the potassium feldspar, and the modifier based on mullite modification and the modified cordierite agent are added, so that the wear resistance, the stain resistance and the heat-conducting property of the obtained ceramic clay are coordinated and improved through co-blending and matching of the raw materials and mutual enhancement and improvement of the raw materials; meanwhile, the product is remarkable in anti-damage stability effect.

The invention discloses a reaction-sintered silicon carbide setter plate and a preparation method thereof. The reaction-sintered silicon carbide setter plate product is obtained through powder granulation, compaction and reaction sintering. Wherein the silicon carbide powder of the four particle size sections is matched, the particle size sections are uniform, stacking is more reasonable, coarse particles form a frame, fine particles are filled among the coarse particles, the powder structure is compact in property, and the compactness of a green body obtained after blank pressing is guaranteed; and spray granulation is performed after ball milling, so that all the raw materials and auxiliary materials are uniformly mixed. The surface of the green body pressed by a set oil pressure mold is also provided with a concave-convex structure, so that the contact area between the load bearing plate and the bottom of the domestic porcelain is reduced, air circulation between the load bearing plate and the bottom of the domestic porcelain is increased, and adhesion is effectively avoided. The product has the advantages of long service life, high strength and fast heat conduction, solves the problems of low strength, low heat conductivity and short service life of mullite, and also solves the industrial pain point of adhesion of a reaction-sintered silicon carbide setter plate.

According to the mullite castable preparation method based on comprehensive utilization of the secondary aluminum ash nonferrous smelting slag, components are regulated and controlled by controlling the molar ratio of Al2O3 to SiO2, so that porous light mullite stably falls into a mullite phase region, and generation of excessive corundum phases is avoided. PMMA microspheres, corn flour, carbonized rice husks and SiO2 coated calcium carbonate composite pore-forming agent systems are adopted, and a layered slurry formula, gradient slip casting and segmented sintering processes are combined, so that the porosity and strength distribution are accurately regulated and controlled, and low-temperature sintering and amorphous phase change control are realized. By optimizing the grading of the porous light mullite aggregate and adding the homologous fine powder, the bonding strength and compressive strength of the castable are improved. And finally, the surface of the castable is coated with a compact mullite coating, so that the porosity is reduced, and the erosion resistance, corrosion resistance and stripping resistance are remarkably improved. The obtained castable has the advantages of light weight, high temperature resistance, high strength, low cost and excellent thermal stability and erosion resistance.

The invention provides an anti-corrosion ceramic sagger and a preparation method thereof.The anti-corrosion ceramic sagger comprises an aggregate layer and a matrix layer, and the aggregate layer is prepared from, by mass, 30-50 parts of yttrium-stabilized zirconia, 20-30 parts of silicon carbide and 15-25 parts of magnesium aluminate spinel; the matrix layer is prepared from the following raw materials in parts by mass: 40 to 50 parts of mullite micro powder, 30 to 40 parts of cordierite micro powder and 10 to 20 parts of binding agent. According to the anti-corrosion ceramic sagger and the preparation method thereof, by optimizing the raw material ratio and the preparation process, the corrosion depth is smaller than or equal to 0.19 mm after the sagger is soaked in the molten salt environment at 900 DEG C for 72 h, the service life is prolonged by 6-8 times compared with that of a traditional corundum sagger, and the anti-corrosion ceramic sagger has wide application prospects.

The invention discloses a wear-resistant and mildew-proof ceramic tile which comprises a green body and a glaze layer attached to the green body, and the wear-resistant and mildew-proof ceramic tile is obtained by coating the surface of the green body with a modified interface agent and then glazing, wherein the glaze layer is prepared from the following raw materials in parts by weight: 40 to 50 parts of silicon dioxide, 30 to 35 parts of aluminum oxide, 15 to 20 parts of modified titanium dioxide, 6 to 10 parts of barium carbonate, 6 to 10 parts of mullite, 5 to 8 parts of silver-loaded zirconium phosphate, 4 to 8 parts of potassium carbonate, 4 to 8 parts of sodium carbonate, 3 to 7 parts of limestone, 3 to 5 parts of sodium borate, 2 to 4 parts of zinc oxide and 0.5 to 1 part of sodium tripolyphosphate. According to the ceramic tile, the modified interface agent with specific composition is introduced between the ceramic tile green body and the glaze layer, modified titanium dioxide and inorganic components (such as aluminum phosphate, aluminum acetylacetonate and tetrapropyl zirconate) in the interface agent form oxides in the sintering process, and the interface bonding strength is remarkably enhanced through physical occlusion; and the long-term wear resistance and mildew resistance of the ceramic tile glaze layer are improved.

The invention discloses a preparation method of a mullite ceramic fiber with a hollow hierarchical structure, and belongs to the technical field of ceramic fiber material preparation. The preparation method comprises the following steps: firstly, preparing hollow mullite fibers by utilizing coaxial electrostatic spinning, and then growing a hierarchical structure of mullite whiskers on the hollow mullite fibers. The preparation method of the hierarchical structure comprises the following steps: by taking hollow mullite fibers as a matrix, carrying out vacuum impregnation with an aluminum-silicon nano powder solution, then carrying out vacuum impregnation with a fluoride solution, and calcining to obtain the hollow hierarchical mullite ceramic fibers. The preparation method of the porous mullite fiber is simple, the pore structure is easy to control, and the heat insulation performance is excellent. The mullite graded fiber prepared by the method has excellent high-temperature resistance and light weight, can be used for preparing a high-temperature-resistant heat insulation piece, and can provide a novel light high-temperature-resistant heat insulation material for the fields of spaceflight and military industry and the like.

The invention belongs to the technical field of motor casing lost foam casting, and particularly relates to a special coating for a motor casing lost foam as well as a preparation method and application thereof. Through a quantitative formula design method, an aggregate proportion calculation formula based on thermal expansion coefficient matching and a grain size distribution correlation formula based on target air permeability, cooperative compounding of quartz powder and bauxite is achieved, and key functional components such as mullite, organic matter fibers and crystalline flake graphite are combined; the unification of high air permeability and excellent crack resistance of the motor shell lost foam coating is realized. The invention further provides a two-time coating gradient drying efficient process matched with the coating, and on the premise that the coating performance is guaranteed, the production efficiency is remarkably improved, and the energy consumption is reduced.

The invention relates to the technical field of silicon mullite bricks, in particular to a method for preparing a low-thermal-conductivity silicon mullite brick by utilizing basalt fibers and ceramic powder. Comprising the following steps of S1, raw material preparation, S2, functional layer preparation, S3, thermal insulation layer preparation and S4, compression molding. The corrosion resistance and the thermal insulation performance of the low-thermal-conductivity silicon mullite brick are further optimized and improved through the synergistic effect of the basalt fibers and the ceramic powder, and the problem that the performance of a composite material is affected due to the fact that the basalt fibers are prone to being pulled out when stressed is solved. By adopting the ceramic powder with the core-shell structure, the mechanical property of the basalt fiber composite material can be remarkably improved, and the salt and alkali resistance and the heat preservation effect of the brick are optimized while the mechanical property of the low-heat-conductivity silicon mullite brick is further improved.

The utility model discloses an intelligent energy-saving heat treatment kiln, which relates to the technical field of kiln equipment and comprises a base, a kiln body is arranged at the top of the base, a movable plate is arranged in the kiln body, a sliding rail is arranged between the movable plate and the base, and a driving structure is arranged on one side of the sliding rail. The kiln body can have good heat insulation performance through the heat insulation layer made of the heat insulation cotton, the heat insulation cotton does not contain any binding agent and is good in environment-friendly performance, meanwhile, the heat resistance and the heat insulation performance of the whole kiln body can be achieved through the heat insulation area made of mullite materials and the light clay heat insulation bricks in the grooves, and secondly, the heat insulation performance of the whole kiln body is improved. According to the intelligent energy-saving heat treatment kiln, the technical problems that the temperature of the surface of a shell is high due to the fact that a water inlet and a water outlet are matched with each other, the working stability and the service life of external equipment and matched components of a kiln body are affected adversely, and meanwhile energy consumption is caused are solved, and the practicability of the whole intelligent energy-saving heat treatment kiln is improved.

The present application relates to the technical field of thin ceramic tile production, and specifically discloses a low-temperature sintered thin ceramic tile and a production method. The thin ceramic tile is mainly made of the following raw materials in parts by weight: 15-25 parts of pyrophyllite, 10-20 parts of potassium feldspar, 10-20 parts of sodium feldspar, 10-20 parts of mullite, 20-30 parts of quartz sand, 6-10 parts of micron metal oxide, 4-6 parts of flake graphite, 4-6 parts of aluminum borate whiskers, 6-8 parts of aluminum oxide fiber, 2-4 parts of metal aluminum powder, 1-3 parts of flux, 3-7 parts of ball clay, 8-12 parts of bentonite, and 13-17 parts of silica sol adhesive. The thin ceramic tile, through the mutual cooperation between the raw materials, can not only achieve low-temperature sintering, but also has the advantages of high breaking strength, high modulus of rupture, and low water absorption, improves the quality of thin ceramic tiles, expands the scope of application, increases the stability of use, prolongs the service life, and meets market demand.

The present invention relates to the technical field of refractory materials, and specifically discloses a lightweight and high-strength refractory ceramic material and a preparation method thereof, comprising 30%-40% lightweight filler (expanded perlite or glass microspheres), 20%-30% corundum or mullite, 10%-15% silicon carbide, 10%-20% high bauxite and 1%-5% dispersant, an oven is used to dry the lightweight filler, a ball mill is used to crush the corundum or mullite and silicon carbide, and a vibrating screen is used to screen them. The present invention ensures that the final ceramic material has the advantages of light weight, high strength, good thermal shock resistance, excellent thermal insulation, high temperature resistance, corrosion resistance, etc., is suitable for structural materials or thermal insulation materials in high temperature environments, and the precise control of humidity, temperature and molding pressure during the preparation process improves the uniformity and performance stability of the material, ensuring an efficient production process.

The invention belongs to the technical field of ceramic materials, and particularly relates to a high-strength building ceramic material and a preparation method thereof. The high-strength building ceramic material is prepared from the following raw materials in parts by weight: 20 to 30 parts of potassium feldspar, 15 to 23 parts of kaolin, 37 to 45 parts of solid waste-based silicon carbide, 1 to 4 parts of talc, 3 to 8 parts of modified mullite whisker and 2 to 5 parts of filler, a preparation process of the modified mullite crystal whiskers comprises the following steps: (1) adding mullite crystal whiskers into an ethanol water solution containing a silane coupling agent, and heating for reaction to obtain pretreated mullite crystal whiskers; and (2) adding the mullite whiskers pretreated in the step (1) into a nickel sulfate aqueous solution, then adding triethylamine and sodium thiosulfate, and carrying out a heating reaction to obtain the modified mullite whiskers. After the raw material components are combined, preparation of a high-strength ceramic material is facilitated, the heat conductivity coefficient can be increased, the heat conduction effect can be enhanced, and the ceramic material is suitable for common home decoration and high-heat-conductivity floor heating ceramic tiles.

The invention relates to the technical field of domestic ceramics, in particular to a high-strength and high-gloss domestic ceramic and a preparation method thereof, and the high-strength and high-gloss domestic ceramic comprises the following raw materials in parts by weight: 35-45 parts of mullite, 15-20 parts of spodumene, 10-15 parts of quartz, 8-12 parts of a modifier doped with barium carbonate, 5-8 parts of a boric oxide additive and 7-11 parts of a yttrium-zinc reconditioning agent. According to the domestic ceramic, mullite, spodumene and quartz are used as matrixes, an added yttrium-zinc compound regulator is used as an antibacterial functional agent, nano-zinc oxide is blended into cobalt nitrate and yttrium nitrate solutions, sintering improvement is performed, and the antibacterial stability of the product is enhanced and optimized through compounding of yttrium, zinc and cobalt; meanwhile, the added modifier doped with barium carbonate and the boron oxide additive are mutually blended and coordinated, so that the antibacterial property, the glossiness and the strength of the obtained domestic ceramic are improved in a balanced and coordinated manner, and the product is remarkable in cold and heat resistance and temperature-resistant stability effect.

The invention relates to the field of refractory castable, in particular to mullite-based modified high-strength refractory castable and a preparation process thereof. The refractory castable is used for solving the problems of low strength and poor wear resistance of the existing refractory castable. The niobium-zirconium alloy and the benzoxazine-PAMAM copolymer are added into the refractory castable, the benzoxazine-PAMAM copolymer wraps a matrix in a three-dimensional network structure, so that the cohesive force is improved, a carbon layer is formed among matrix particles after sintering to improve the overall compactness of the material, micropores in the matrix of the refractory castable can be filled with the niobium-zirconium alloy, the porosity is reduced, and the porosity of the refractory castable is improved. The refractory castable disclosed by the invention can be used for reducing stress concentration, remarkably improving normal-temperature compression resistance and breaking strength, maintaining long-term high-temperature strength and ensuring that the refractory castable can still be kept stable in severe environments such as high temperature, high pressure and corrosion, so that the service life is prolonged, and the production safety is improved.

The invention discloses a corundum high-strength wear-resistant castable, which belongs to the field of castable, and comprises a raw material, an auxiliary material, a binding agent and an additive, the raw material is corundum aggregate, and the auxiliary material comprises corundum fine powder, mullite fine powder, an inorganic non-metallic material and stainless steel fiber, the binding agent comprises calcium aluminate cement, hydrated alumina, silica sol, aluminum dihydrogen phosphate and refractory clay, and the additives comprise sintered spinel fine powder, silica micropowder, activated alumina micropowder, zirconia micropowder, a coagulant, a retarder, a dispersant, a flocculant, a plasticizer, a water-retaining agent, an anti-settling agent and a preservative. The corundum high-strength wear-resistant castable is prepared by mixing the raw materials, the auxiliary materials, the binding agent and the additive, so that the corundum high-strength wear-resistant castable has excellent strength, wear resistance, fire resistance and thermal shock resistance during use, and further the actual use effect and performance of the corundum high-strength wear-resistant castable are ensured; and the service life of the product is prolonged.

The invention discloses a method for preparing a mullite-based porous ceramic material from biochar and coal co-gasification fly ash, and belongs to the technical field of porous ceramic materials. Aiming at the technical bottlenecks of single raw material, dependence of a pore-forming mode on an additional material, poor controllability of a pore channel structure, low resource utilization efficiency of industrial byproducts and the like in the preparation of the existing mullite-based porous ceramic, the invention provides the preparation method of the mullite-based porous ceramic. The preparation method comprises the following steps: by taking charcoal and coal co-gasification fly ash as a silicon source and an additional aluminum source as a mixed raw material, proportioning according to a specific mass ratio of aluminum oxide to silicon oxide, adding a binder and a pore-forming agent, and uniformly mixing to obtain a mixture; and adding a whisker accelerant, granulating, sieving, carrying out static-pressure blank forming, drying and sintering to obtain the mullite-based porous ceramic material. The preparation method has a new path for preparing the mullite-based porous ceramic with remarkable resource value and industrialization potential, and provides technical support for promoting high-value utilization of multi-source solid wastes and development of functional ceramics.

The invention relates to the technical field of special functional coating materials for lost foam casting, and particularly discloses a special coating for a large machine tool casting lost foam as well as application and a use method of the special coating. According to the invention, the full-temperature-range functional composite material and the composite aggregate are used for synergistic reinforcement, and mullite is used for high-temperature reinforcement; the temperature-sensitive polymer modified graphite can realize intelligent temperature response of graphite performance; spodumene is used as a thermal expansion adaptive fluxing agent, so that medium-temperature healing and thermal expansion adjustment of a coating system are facilitated; the composite reinforced fibers are reinforced and toughened aiming at large thermal stress of thick and large parts; as an ultralow-temperature glazing agent, the boron-containing glazing agent can form an initial liquid phase at about 450 DEG C to seal the surface of the coating and purify a ventilation channel; the rare earth oxide serving as a high-temperature phase stabilizer can be dissolved in mullite crystal lattices, so that the high-temperature phase stability is improved, and ceramic nodes are refined. Through raw material design, on the premise of ensuring moderate air permeability, the ultrahigh strength and crack resistance of a coating system at extremely high temperature are improved.

The invention relates to the technical field of lost foam casting, in particular to a lost foam composite coating, the lost foam composite coating takes a refractory material of an investment casting regenerated shell membrane as a refractory aggregate, the refractory aggregate comprises mullite and a mixture containing an inorganic preservative A and a sintering stripping material B, and one or more of quartz powder and graphite are selected. In the invention, an efficient anti-corrosion additive with sintering stripping is researched and developed as a refractory material auxiliary additive, and meanwhile, low-price refractory materials such as regenerated mullite and recycled quartz powder are utilized to form the lost foam coating aggregate, so that the selection of traditional refractory aggregate is broken through, and the reutilization of waste resources is realized; the environment pollution is reduced while the raw material cost is reduced, meanwhile, the aggregate performance is optimized by adding the raw materials such as calcium oxide and iron oxide red, and the comprehensive performance such as air permeability, suspension stability, high-temperature strength and toughness of the coating is remarkably improved through reasonable matching of the composite binder.

The invention provides an anti-erosion refractory material for calcination of an aluminum ash rotary kiln and a preparation method of the anti-erosion refractory material, and relates to the technical field of refractory materials. Comprising the following raw materials in percentage by mass: 20%-70% of flint clay with the particle size of 0-5mm, 5%-40% of synthetic mullite with the particle size of 0-5mm, 5%-20% of synthetic mullite powder with the particle size of 0-0.074 mm, 1%-20% of silica powder with the particle size of 0-0.074 mm, 1%-15% of synthetic material powder with the particle size of 0-0.074 mm and 1%-15% of clay with the particle size of 0-0.074 mm. According to the anti-erosion refractory material for calcination of the aluminum ash rotary kiln and the preparation method thereof, a high-viscosity glass phase is generated in situ, and a dynamic protection layer is formed on the surface of the refractory material to prevent permeation of harmful gas, so that the thickness of a metamorphic layer is reduced, damage to a refractory product is slowed down, and the service life is prolonged; through the synergistic effect of the silica powder and the synthetic powder, the refractory material can be sintered at a low temperature, and the production energy consumption is reduced.

The invention provides a hierarchical porous silicon material and a preparation method thereof, and belongs to the technical field of comprehensive utilization of fly ash. The preparation method of the hierarchical porous silicon material provided by the invention comprises the following steps: mixing fly ash and an activating agent, and calcining to obtain activated fly ash; the activating agent comprises at least one of sodium salt and potassium salt; and mixing the activated fly ash with hydrochloric acid, and carrying out acid etching to obtain the hierarchical porous silicon material. According to the invention, at least one of sodium salt and potassium salt is adopted to activate the fly ash, and at least one of Na < + > and K < + > in the activation process can promote the conversion of mullite in the fly ash to different mineral phase aluminosilicate, so that a nepheline structure of Na and / or K is formed; and then hydrochloric acid is adopted for acid etching, and the alumina component can be selectively etched, so that the hierarchical pore channel is constructed, the process is simplified, and template-free preparation of the hierarchical pore silicon material is realized.

The invention relates to a low-temperature sintered self-reinforced mullite whisker porous ceramic and a preparation method thereof. According to the preparation technology disclosed by the invention, the sintering temperature is successfully reduced while the toughening performance of the material is remarkably improved, which has an extremely important influence on reduction of the production cost and optimization of the material performance. The porous ceramic with an in-situ mullite whisker skeleton is prepared by combining an in-situ whisker generation method, a pore-forming agent adding method and a sintering aid method. The optimal synthesis process of the mullite ceramic is obtained by accurately regulating and controlling the raw material ratio, the sintering temperature and the pore-forming agent type. In addition, growth of mullite crystal nucleuses is promoted through the synergistic effect of the sintering aid and the whisker catalyst, and low-temperature sintering of the mullite ceramic is achieved. The invention aims to explore and realize an optimization method for low-temperature sintering, toughening and strengthening, so as to promote the development and application of the porous mullite ceramic in a plurality of application fields such as sound absorption, heat preservation, filtration and catalyst carriers.

The invention provides a high-temperature-resistant soil raw material, and belongs to the technical field of high-temperature-resistant materials. The high-temperature heat-resistant soil raw material comprises the following raw materials in percentage by weight: 23-35% of basic raw material with the particle size of 3-8mm; 12%-28% of a strengthening additive with the particle size smaller than or equal to 0.35 mm; 3%-10% of a functional auxiliary material; the basic raw material is composed of raw ore and rock dry burning mud, spodumene raw ore, quartz and feldspar, and the heat-resistant temperature of the high-temperature heat-resistant soil raw material is greater than or equal to 500 DEG C (can reach 729 DEG C in a short time); the thermal shock resistance is improved by the high alumina content and the mullite structure, cracking is avoided when the temperature difference is larger than or equal to 300 DEG C, the thermal expansion system is low (lt: 4 * 10 / DEG C), heat conduction is uniform, local overheating is avoided, and the characteristics of rapid cooling and rapid heating resistance, high mechanical strength, good chemical stability and the like are achieved; the electric cooker inner container is suitable for electric cooker inner containers, stewpots and other electric appliance matching part products, and the requirements of IH heating, open fire heating and other daily cooking utensils are met.

The invention relates to the technical field of sand mold casting, and particularly discloses a gradient exhaust sand mold for an aluminum alloy thin-walled workpiece and a preparation method thereof.The sand mold comprises a cavity surface layer (with the hardness ranging from 90 HB to 95 HB), a transition layer (with the hardness ranging from 80 HB to 70 HB and a back sand layer (with the hardness ranging from 60 HB to 65 HB) which are arranged from inside to outside, and microporous ceramic exhaust rods (with the diameter ranging from 0.3 mm to 0.8 mm and the distance ranging from 1 mm to 3 mm) are embedded in the cavity surface layer; the exhaust rod is composed of a mullite fiber matrix and a nanometer gamma-AlO coating, the porosity is 40-50%, and the exhaust rod penetrates through the back sand layer to form a directional exhaust network. The preparation method comprises the following steps: mixing sand layer by layer (the cavity layer contains 1.0-1.5% of phenolic resin, and the back sand layer contains 0.4-0.6% of resin and 4-6% of starch); when sand is filled to the position 1-3 mm away from the surface of the cavity, an exhaust rod is implanted (the positioning precision is + / -0.1 mm); gradient compaction is carried out (the high pressure of a cavity is 3.0-4.0 MPa, the vibration of a transition area is 20-30 Hz, and the back sand airflow is 0.1-0.2 MPa); and carrying out microwave curing (2.5 to 3.5 kW, 60 to 120 s). The defects of hot cracks and air holes of the thin-wall part (smaller than or equal to 5 mm) are overcome synchronously, and the casting yield is increased to 95% or above.

The invention relates to the technical field of mullite brick production, in particular to a mullite brick production pouring device which comprises a conveying frame. The storage barrel is arranged above the conveying frame through a supporting frame; the fixing frame is fixedly mounted on the top surface of the conveying frame; the air cylinder is fixedly installed on the top face of the fixing frame, and the telescopic end of the air cylinder penetrates through the top face of the fixing frame; the pressing plate is fixedly installed at the telescopic end of the air cylinder. Compared with the prior art, by arranging the pressing plate and the cleaning assembly, in the resetting process of the pressing plate, a third transmission gear drives a connecting rod to rotate, a coil spring accumulates force, and when the pressing plate is completely reset, the coil spring releases energy, drives the connecting rod to rotate reversely and drives a reciprocating lead screw to rotate, so that a sliding plate is driven to slide back and forth along a guide rod, and a cleaning scraping plate cleans the bottom face of the pressing plate; the bottom face of the pressing plate can be automatically cleaned after the pressing plate is used every time, residues are prevented from affecting next-time use, and therefore automatic cleaning of the bottom face of the pressing plate and collection of materials are achieved.

The invention relates to the technical field of ceramic materials, in particular to a ceramic material and a preparation method and application thereof. The invention provides a ceramic material, which is prepared from the following raw materials in percentage by mass: 5 to 30 percent of ball clay, 5 to 25 percent of purple grit mud, 10 to 35 percent of mullite, 15 to 40 percent of cordierite and 3 to 10 percent of pore forming agent. The ceramic material has the characteristics of good heat storage property, impact resistance and light weight. The pizza stone plate can be comparable with a high-grade pizza stone plate made of natural volcanic materials.

The invention belongs to the technical field of fly ash solid waste resource utilization, and particularly relates to a method for preparing flaky alumina by using fly ash, which is characterized by comprising the steps of fly ash pretreatment, intermediate preparation and alumina preparation, ammonium fluoride used in the alumina preparation step is a recycling product of fluorine-containing tail gas in the step, and ammonium fluoride used in the alumina preparation step is a recycling product of fluorine-containing tail gas in the step. The preparation method comprises the following specific operation steps: 1) pretreating fly ash, namely treating fly ash with a NaOH solution and an HCl solution to obtain a mixture of quartz and mullite; (2) preparing an intermediate, namely reacting a mixture of quartz and mullite with CeO2 to obtain a K3Al (SO4) 3 intermediate; and 3) preparing aluminum oxide, purifying the K3Al (SO4) 3 intermediate, grinding and mixing the purified K3Al (SO4) 3 intermediate and ammonium fluoride crystals according to the F / Al molar ratio, and roasting at high temperature to obtain a flaky aluminum oxide product. The method has the beneficial effects that the problem of low purity of flaky aluminum oxide in the existing method for preparing the aluminum oxide from the fly ash is solved, and the purity of the flaky aluminum oxide is 99.2-99.8%.

The invention discloses a fracturing proppant using coal gangue and fly ash and a preparation process thereof, and relates to the field of fracturing proppants, the fracturing proppant comprises coal gangue, fly ash, silica fume, nanometer alumina, a composite pore-forming agent and a fluxing agent, and the preparation process comprises raw material pretreatment, mixing granulation, microwave-gradient sintering and post-treatment. The raw material pretreatment comprises the following steps: removing iron and impurities through carbon thermal reduction-magnetic separation; the composite pore-forming agent is enriched on the surface of the green body during mixed granulation; the microwave-gradient sintering is used for cooperatively regulating and controlling growth of mullite crystals through microwave preheating and resistance heating to form an internal acicular mullite interlaced structure and a surface micro-convex structure; a finished product is obtained through post-treatment grading and surface cleaning. Resource utilization of industrial solid waste is achieved, the strength and flow conductivity of the proppant are improved through raw material synergy, crystal structure regulation and control and surface microstructure design, preparation energy consumption is reduced, and the proppant is suitable for oil and gas field fracturing engineering.

The invention discloses a silicon mullite brick with high connection stability and a production process thereof, and belongs to the technical field of silicon mullite brick preparation. Through the composite formula design of the multi-graded silicon carbide aggregate and the in-situ generated mullite precursor and in combination with a microwave-air pressure coupling sintering process, the optimization of the material structure is realized. Wherein the silicon carbide aggregate is subjected to surface etching to form a microporous structure, and the microporous structure and the aluminum phosphate nanofiber reinforced matrix form a three-dimensional interlocking network; dual-band microwave alternate radiation and staged air pressure dynamic regulation and control are adopted, substance diffusion is promoted at low temperature, and meanwhile pore formation is inhibited at high temperature; and in the gradient cooling stage, the grain boundary stability is enhanced through controllable oxygen partial pressure and rare earth steam treatment. The process effectively improves the interface bonding strength and thermal shock resistance of the silicon mullite brick, reduces the sintering energy consumption, and is suitable for refractory material preparation of high-temperature equipment such as a cement kiln and an incinerator.

The invention relates to the field of fire-resistant and heat-insulating bricks, and discloses a multifunctional fire-resistant and heat-insulating brick and a manufacturing process thereof. Comprising the following raw materials in parts by weight: 10-15 parts of silicon carbide, 10-20 parts of mullite, 5-10 parts of cordierite, 30-40 parts of aluminum oxide, 5-10 parts of zirconium oxide, 2-4 parts of titanium dioxide nanoparticles, 6-9 parts of a cleaning agent, 3-5 parts of yttrium oxide and 1-12 parts of a micropore forming agent. By adding manganese oxide and cerium oxide, when the surface of the brick body is in contact with reducing substances or impurities, the oxidation reaction of the reducing substances or impurities can be promoted, and the impurities are converted into oxides which are easy to remove, so that the high-temperature oxidation self-cleaning function is realized, and the capability of keeping the brick body clean and stable in performance in a complex high-temperature environment is enhanced; brick body corrosion and performance degradation caused by impurity deposition are reduced, and therefore the problem that in a high-temperature industrial environment, dirt and impurities are prone to being attached to the surface of a traditional fire-resistant heat-insulating brick, and the heat-insulating performance of the traditional fire-resistant heat-insulating brick is affected is solved.

The invention relates to the technical field of slurry, and particularly discloses secondary aluminum ash-based silicon-aluminum series refractory slurry and a preparation method thereof. The invention discloses secondary aluminum ash-based silicon-aluminum series refractory mortar. The raw materials of the mortar comprise an aluminum ash material and a modified water glass binding agent, the modified water glass binding agent accounts for 10-15% of the weight of the slurry; the raw materials of the aluminum ash material comprise the following components in parts by weight: 10-30 parts of low-aluminum mullite, 30-50 parts of calcined secondary aluminum ash, 5-15 parts of secondary aluminum ash, 5-15 parts of silica powder, 3-8 parts of a composite additive, 0-5 parts of potassium feldspar powder and 1-5 parts of bentonite. The refractory mortar provided by the invention has excellent high temperature resistance, thermal shock resistance stability and thermal insulation performance.