52results about "Calcium aluminates" patented technology

The present invention relates to a method for co - processing and resource utilization of overhaul slag, fly ash, and desulfurized gypsum. The method comprises the following steps: Step 1) dehydrate and then dry the desulfurized gypsum, add calcium carbonate to the dried desulfurized gypsum, and collect SO3 gas; Step 2) carry out an autoclave reaction on the SO3 gas obtained in Step 1, water, and fly ash. After solid - liquid separation, silicon dioxide and an aluminum sulfate solution are obtained; Step 3) crush and ball - mill the overhaul slag, and carry out first - stage roasting with a peroxide at high temperature to obtain clinker 1; leach out sodium fluoride from clinker 1 by water immersion, and then add it to the aluminum sulfate for second - stage roasting to obtain clinker 2; Step 4) mix clinker 2 with water for leaching to obtain a filtrate and a filter residue; Step 5) calcine calcium oxide and the filter residue to obtain calcium aluminate. The beneficial effect of the present invention aims to synergistically utilize the sodium, aluminum, fluorine, and lithium elements, the aluminum and silicon elements of fly ash, and the calcium element in desulfurized gypsum to achieve the purpose of resource conversion.

The invention relates to a recycling method of chemical polishing waste liquid, which comprises the following steps: (1) carrying out first pH regulation treatment on the chemical polishing waste liquid containing phosphate radicals, sulfate radicals, aluminum ions and + 3 valent iron ions to obtain aluminum mud and aluminum-removed liquid; (2) sequentially carrying out second pH regulation treatment, third pH regulation treatment and dealumination treatment on the aluminum mud to obtain a hydrated calcium aluminate product; (3) the aluminum-removed liquid is subjected to phosphorus removal treatment, and first phosphorus mud and phosphorus-removed liquid are obtained; sequentially carrying out fourth pH regulation treatment and first evaporative crystallization treatment on the first phosphorus sludge to obtain a sodium phosphate product; and sequentially carrying out fifth pH regulation treatment and second evaporative crystallization treatment on the dephosphorized liquid to obtain a sodium sulfate product. According to the method disclosed by the invention, phosphorus, sulfur and aluminum in the chemical polishing waste liquid are completely separated by utilizing different solubility of different substances in the solution when the pH value is the same, and a sodium phosphate product, a sodium sulfate product and a hydrated calcium aluminate product are respectively obtained, so that complete recycling of elements in the chemical polishing waste liquid is realized, and no byproduct waste is produced.

The invention relates to a method for producing mayenite, comprising the following sequential steps: a) preparing a feed suitable for obtaining, at the end of step c), a product comprising more than 90% mayenite in percentage by weight based on the weight of the crystalline phase, said mayenite comprising calcium and / or strontium, aluminum and oxygen; b) melting the feedstock until a molten material is obtained; c) cooling the molten material in order to solidify the molten material and obtain a polycrystalline fused product; the melting is carried out using an electric arc furnace and in a reducing medium.

The purpose of the present invention is to provide a calcium aluminosilicate-based compound that, when added to cement or the like, has high compressive strength and is capable of imparting a favorable surface finish. This calcium aluminosilicate-based compound contains, as chemical components, 30-60 mass% of CaO, 10-60 mass% of Al2O3, 1-15 mass% of SiO2, 10-50,000 ppm of P2O5 by mass ratio, and 0.1-1 mass% of MgO.

The invention relates to a method for binding sulfates in a body of water comprising sulfates, a calcined mixture prepared by calcining a mixture comprising calcium oxide and calcium alumina and / or calcium aluminate and cooling it to bind sulfates in a body of water, and the use of at least one element comprising CaO and mayenite supergroup and / or of a powder mixture and / or calcined mixture comprising at least one calcium aluminosilicate and / or at least one calcium aluminosilicate and / or calcium silicate for binding sulfates in a body of water.

The application discloses a method for preparing calcium aluminate for water treatment agent from impurity-removed solid waste by improved Bayer process, and belongs to the technical field of industrial solid waste utilization and water treatment agent preparation. The method takes desiliconized slag and deironed slag generated by improved Bayer process as core raw materials, and prepares calcium aluminate through the steps of solid waste washing treatment, filtrate recycling recovery, precise proportioning, mixing, grinding, high-temperature calcination reaction, crushing and screening, product detection and packaging, etc. Fluxing agents can be flexibly added or a segmented cooling optimization process can be adopted. The application realizes high-value resource utilization of solid waste of improved Bayer process, solves the problems of high cost and solid waste pollution caused by the dependence of traditional calcium aluminate preparation on natural minerals, and has high product purity, low heavy metal content and stable performance. The process is simple and controllable, and is suitable for large-scale production, and has remarkable environmental and economic benefits, and has a good application prospect in the field of water treatment agent raw material production.

The utility model discloses a pyrogenic process and wet process combined harmless and resource treatment system for aluminum ash, which comprises an aluminum ash raw material manufacturing subsystem, a mixed raw material manufacturing subsystem and a calcium aluminate manufacturing subsystem, the aluminum ash raw material manufacturing subsystem crushes, grinds and treats primary aluminum ash and secondary aluminum ash to obtain aluminum ingots and aluminum ash raw materials; the mixed raw material manufacturing subsystem is used for denitrifying the obtained aluminum ash raw material through a wet processing system, and mixing and grinding the denitrified aluminum ash, limestone and bauxite according to a certain proportion to obtain a mixed raw material; and the calcium aluminate production subsystem is used for carrying out pyrogenic calcination on the obtained mixed raw material and cooling to obtain calcium aluminate, and treating the calcium aluminate to obtain the finished product calcium aluminate. Nitrogen in the aluminum ash is removed and calcium aluminate is generated in a mode of combining a pyrogenic process and a wet process, and the calcium aluminate can be used for producing high-alumina cement and can also be used for producing building fireproof materials; the hazardous waste aluminum ash is harmless and recycled, and waste is turned into wealth.

The invention discloses a resource utilization method for preparing calcium aluminate through aluminum ash denitrification aluminum extraction-calcium roasting, and belongs to the technical field of aluminum ash resource processing. The method comprises the following steps: carrying out dry grinding on raw material aluminum ash to realize monomer dissociation to micron size, sieving, carrying out wet grinding on the obtained aluminum ash fine powder in a water-containing medium for denitrification, and sieving to recover metal aluminum and obtain aluminum-rich slag slurry; the aluminum-rich slag slurry is subjected to solid-liquid separation and soluble salt leaching treatment, and purified aluminum-rich slag is obtained; and the purified aluminum-rich slag is subjected to high-temperature calcium roasting, and the calcium aluminate system steelmaking refining slag with 12CaO. 7Al2O3 as the main crystalline phase is obtained. According to the method, physical separation, wet chemical reaction and pyrogenic calcination are combined for cooperative treatment, harmful elements such as nitrogen and fluorine can be efficiently removed, the aluminum ash of metal aluminum in the aluminum ash can be recycled, and harmless treatment, zero waste and all-component high-value utilization of the aluminum ash are achieved.

The invention provides a method for producing calcium aluminate powder by replacing part of bauxite with aluminum ash. The method comprises the following steps: respectively discharging secondary aluminum ash, limestone and bauxite from a raw material bin according to a ratio, and feeding into a stirrer; the preparation method comprises the following steps: uniformly stirring raw materials in a stirrer to obtain a mixture, spraying a liquid binder while stirring, and feeding the mixture into a high-pressure roller mill for treatment to obtain a material cake; feeding the material cake into a vertical mill through a discharging chute for grinding, separating fine powder through a powder concentrator under the driving of airflow, collecting the fine powder through a dust collector to obtain a raw material, and feeding the raw material into a homogenizing silo for storage; and feeding the raw material in the homogenizing silo into a preheater for preheating, feeding into a rotary kiln for calcining to obtain clinker, cooling the clinker, and grinding into powder to obtain the calcium aluminate powder. According to the invention, the homogeneity problem of the raw materials is effectively solved, the operation efficiency and stability of the system are improved, high-value utilization of multiple solid wastes is realized, the production operation environment is improved, the equipment corrosion risk is reduced, and the process adaptability is strong.

To provide a method for efficiently regenerating wastewater solutions of sodium hydroxide. [Solution] A method for regenerating a waste sodium hydroxide aqueous solution containing aluminum, comprising the steps of: mixing and reacting an aqueous slurry containing a calcium compound with the waste sodium hydroxide aqueous solution to form a reaction solution containing a supernatant liquid and a solid reaction residue; and subjecting the reaction solution to a solid-liquid separation treatment to remove the reaction residue, thereby recovering the supernatant liquid as a regenerated sodium hydroxide aqueous solution.

A molded sintered body containing a mayenite type compound, an inorganic binder sintered material, and a transition metal, wherein a content of the inorganic binder sintered material is 3 to 30 parts by mass with respect to 100 parts by mass of the molded sintered body, and the molded sintered body has at least one pore peak in each of a pore diameter range of 2.5 to 20 nm and a pore diameter range of 20 to 350 nm. A method for producing the molded sintered body, including mixing a precursor of a mayenite type compound and a raw material of an inorganic binder sintered material to prepare a mixture; molding the mixture to prepare a molded body of the mixture; firing the molded body to prepare a fired product; and supporting a transition metal on the fired product to produce a molded sintered body.

The invention relates to a method for preparing hydrocalumite to synergistically remove multicomponent impurities in rare earth feed liquid, and belongs to the technical field of separation, purification and high-value utilization of rare earth feed liquid. The method comprises the following steps: selecting air-cooled blast furnace slag, crushing, screening, uniformly mixing with NaOH particles, roasting, and air-cooling to room temperature to obtain an air-cooled mixture; leaching the air-cooled mixed material, stirring in distilled water, filtering, rinsing with distilled water, and drying to obtain the rare earth feed liquid impurity removal agent; the rare earth feed liquid is taken, the rare earth feed liquid impurity removal agent is placed in the rare earth feed liquid with the pH adjusted to be stirred, and the rare earth feed liquid with impurities removed is obtained. The method is mild in reaction condition, simple to operate and control, high in impurity removal efficiency, capable of well connecting upstream and downstream processes of rare earth smelting, excellent in process compatibility, high in universality for multi-component impurities in the rare earth feed liquid and capable of well covering removal of all-component impurities in the rare earth feed liquid.

An oxide ion-conducting solid electrolyte is provided. The oxide ion-conducting solid electrolyte contains a mayenite-type compound having a representative composition represented by Ca12Al14O33, and at least one metal element M selected from lanthanum (La) and yttrium (Y), wherein the metal element M is contained in a range of from 0.4 mol% through 5.3 mol% in terms of an oxide relative to the whole of the oxide ion-conducting solid electrolyte.

The invention discloses an iron-modified calcium-aluminum compound as well as a preparation method and application thereof. The preparation method of the iron-modified calcium-aluminum compound comprises the following steps: mixing a calcium source, an aluminum source and an iron source, and calcining, wherein the molar ratio of Ca to Al in the calcium source and the aluminum source is (1-1.3): 1, and the ratio of the total mass of the calcium source and the aluminum source to the mass of iron ions in the iron source is 1: (0.01-50). The calcium-aluminum compound is modified through iron doping, and when the calcium-aluminum compound is applied to desulfurization wastewater treatment, the removal efficiency of chlorine / thallium ions can be remarkably improved, the use amount of iron-modified mayenite can be reduced, and then the cost is reduced. Meanwhile, the obtained chlorine / thallium removal product has excellent removal rate on carbonyl sulfide and hydrogen sulfide.

The invention relates to a method for preparing calcium aluminate by using alkaline residues, which comprises the following steps: adding an induced settling agent into alkaline residue slurry to promote the growth of calcium carbonate crystal grains in the alkaline residue slurry and further promote the settling of calcium carbonate, aluminum calcium carbonate and other products so as to facilitate subsequent better solid-liquid separation; carrying out dealkalization type liquid-solid separation treatment on the sedimentation liquid to obtain low-sodium modified alkaline residues and catalytic filtrate; reacting the catalytic filtrate with aluminum ash to obtain sodium aluminate, ammonia gas, methane and hydrogen; then carrying out solid-liquid separation to obtain modified aluminum ash with less leached fluorine and less volatile ammonia; and preheating and calcining the modified alkaline residues and the modified aluminum ash to obtain a target calcium aluminate product. The preparation method provides a thought for preparing high-quality calcium aluminate from the alkali residues discharged in the Bayer process aluminum oxide production process.

This invention belongs to the field of ceramic materials technology, specifically relating to ceramic fuse shells and their preparation method. The preparation method includes: ball milling a mixture of calcined α-alumina, borosilicate glass frit, γ-alumina, a composite grain bridging agent, a composite pore-sealing reinforcing agent, and deionized water; adjusting the pH to a neutral range; adding an aqueous solution containing polyvinyl alcohol and continuing mixing; sieving and spray drying to obtain granules; mixing with magnesium stearate and pressing into green bodies; placing the green bodies in a degreasing furnace; heating to different temperatures in stages under an air atmosphere and holding at those temperatures to complete degreasing; transferring the degreased green bodies to a sintering furnace; heating to a high temperature and holding at that temperature under a nitrogen protective atmosphere; and cooling in the furnace to obtain the finished ceramic shell. This invention, by introducing a composite grain bridging agent and a composite pore-sealing reinforcing agent, combined with staged degreasing and nitrogen atmosphere sintering, effectively improves the density, insulation performance, and bending strength of the shell, making it suitable for fuse applications.

The invention belongs to the technical field of asbestos tailing utilization, and particularly discloses an asbestos tailing full-resource utilization process. The method provided by the invention comprises the following steps: crushing and sieving asbestos tailings, adding a sulfating roasting reagent and ammonium bisulfate to obtain a mixed material, and roasting the mixed material in a fluidized bed; after heat preservation treatment, water is added for a leaching reaction, and leaching residues and filtrate are obtained through solid-liquid separation; adjusting the pH value of the filtrate to obtain a mixed precipitate of ferric hydroxide and nickel hydroxide and a sulfate solution, performing evaporative crystallization on the sulfate solution, and performing roasting treatment to obtain a mixed oxide; and adding aluminum powder into the mixed oxide, and carrying out aluminothermic reduction reaction to obtain the magnesium ingot. According to the method, high-valued utilization of various elements in the asbestos tailings can be achieved, circular economy and closed-loop utilization can also be achieved, and the economic effect of enterprises is improved.

The invention relates to the technical field of wastewater dechlorination and resource utilization, in particular to a titanium-modified calcium-aluminum compound and a preparation method thereof, a dechlorination method of chlorine-containing industrial wastewater and regeneration application of a dechlorination product, and specifically, a calcium-containing raw material, an aluminum-containing raw material and a titanium-containing raw material are uniformly mixed and calcined to obtain the titanium-modified calcium-aluminum compound; the titanium modified calcium aluminum compound is low in raw material price, simple to prepare, clean and environment-friendly, and has a good dechlorination effect when being used for removing chloride ions in industrial wastewater, and the obtained dechlorination product can be subjected to dechlorination regeneration, can be used for dechlorination of industrial wastewater in a follow-up cycle for many times, and has a good recycling value.

An oxide ion–conducting solid electrolyte comprising: a mayenite compound having a typical composition represented by Ca12Al14O33; and a crystal phase of cerium oxide (CeO2).

The application belongs to the technical field of metal recycling and utilization, and provides an aluminum ash resource utilization method, in which metallic aluminum in aluminum ash is separated out first, and the remaining pretreated aluminum ash with low metallic aluminum content is washed with water, and then gamma type aluminum oxide and aluminum nitride in the aluminum ash are dissolved with sulfuric acid to obtain aluminum ammonium sulfate, aluminum sulfate solution and sulfuric acid insoluble alpha type aluminum oxide, the sulfuric acid insoluble alpha type aluminum oxide is mixed with calcium carbonate, and then high-temperature calcination and melting reaction are carried out to produce calcium aluminate, the calcium aluminate can be used as an aluminum source for subsequent production of polyaluminum chloride, the method of the application does not produce nitrogen gas, reduces the generation of hydrogen, has small danger and small pollution, eliminates the influence of fluoride, improves the resource utilization value of aluminum ash, and the recovery rate of metallic aluminum can reach 89.2%.

This utility model discloses a production line for producing calcium aluminate using aluminum ash, comprising a mixer, a first ball mill, a brick press, a tunnel kiln, and a conveying mechanism. The mixer is used to mix high-alumina alumina and calcium carbonate; the first ball mill is used to grind the mixture after mixing into a mixed powder; the brick press is used to press the mixed powder ground by the first ball mill into brick blanks; the tunnel kiln is used to calcine the brick blanks and includes a drying kiln chamber, a pre-firing kiln chamber, a calcining kiln chamber, and a cooling kiln chamber arranged sequentially; the conveying mechanism includes a material carrier and a drive assembly. The material carrier is used to carry the brick blanks, and the drive assembly is used to drive the material carrier sequentially through the drying kiln chamber, the pre-firing kiln chamber, the calcining kiln chamber, and the cooling kiln chamber. This utility model's production line for producing calcium aluminate using aluminum ash can reduce the impurity content of calcium aluminate, meet the requirements for the use of calcium aluminate in the water purification agent industry, and is conducive to its widespread application in the water purification agent industry, thus expanding the application range of aluminum ash.

This invention relates to the field of solid waste treatment and comprehensive resource utilization in the aluminum alloy processing industry, and discloses a method for the resource utilization of high-speed iron aluminum ash, comprising the following steps: (I) a coarse crushing, ball milling and screening stage, in which the high-speed iron aluminum ash is coarsely crushed, ball milled and then screened to obtain secondary aluminum ash, coarse material and fine material; (II) a magnetic separation stage, in which the coarse material and fine material are magnetically separated to obtain aluminum-containing material and iron-containing material; (III) a mixed smelting stage, in which the secondary aluminum ash, iron-containing material and quicklime are mixed to obtain a mixture, and the mixture is smelted to obtain calcium aluminate melt and molten iron. This solution effectively improves the resource utilization rate of high-speed iron aluminum ash by smelting the mixture of secondary aluminum ash, iron-containing material and quicklime in a furnace to recover iron resources in the form of molten iron; compared with the existing technology that treats iron-containing material and secondary aluminum ash separately, it not only effectively saves processing steps and shortens processing time, but also treats two kinds of hazardous waste (secondary aluminum ash and iron-containing material) simultaneously, and significantly reduces processing energy consumption and improves production efficiency.

The application discloses a harmless preparation method of calcium aluminate for water treatment from industrial aluminum ash, realizes harmless treatment of secondary aluminum ash, efficiently recovers aluminum in the aluminum ash, greatly improves purity of the calcium aluminate, reduces heavy metal ions, realizes effective treatment of the heavy metal ions, and has the following advantages: the calcium aluminate product obtained by the application has relatively simple phases, mainly Ca3Al2O6 and Ca12Al14O33 two phases with high calcium content; the method for preparing the calcium aluminate has low process cost, simple process, environmental protection and no pollution; the method can be widely applied to by-products generated in the aluminum industry; the method maximally improves aluminum utilization rate and effectively treats harmful elements such as heavy metals; and the final calcium aluminate product mainly contains Ca3Al2O6 and Ca 12 Al 14 O 33 two phases with high calcium content.

The present invention relates to a method for producing mayenite in the form of an electride, comprising: a) producing a feedstock suitable for obtaining, at the end of the following step c), a product containing more than 90% mayenite, comprising calcium and / or strontium, aluminum and oxygen atoms, as a mass percentage based on the mass of the crystalline phase; b) melting the feedstock until a molten material is obtained; and c) cooling the molten material to solidify it and obtain a polycrystalline molten product, wherein the melting is carried out using an electric arc furnace and in a reducing medium.

The present application relates to a kind of calcining control method for preparing calcium aluminate from aluminium ash, and the method comprises the following steps: judging the aluminum content index of secondary aluminium ash, classifying secondary aluminium ash according to the aluminum content index, obtaining raw material aluminium ash by matching different types of secondary aluminium ash, and controlling the aluminum content index of raw material aluminium ash.The method can solve the technical problems of normal operation affected by ring formation in the tail of rotary kiln and low firing rate of calcium aluminate caused by material caking when preparing calcium aluminate from aluminium ash.

The invention relates to the technical field of catalysts and preparation thereof, and discloses a calcium aluminate material as well as a preparation method and application thereof, and the calcium aluminate material contains 5-30wt% of calcium oxide and 70-95wt% of aluminum oxide; the crystal phase composition of the calcium aluminate material meets the conditions that I25.4 degrees / I57.5 degrees is larger than or equal to 3, I34.1 degrees / I57.5 degrees is larger than or equal to 3, and I30.1 degrees / I57.5 degrees is smaller than or equal to 0.5. The calcium aluminate material has special crystalline phase composition and physical properties, main crystalline phases of the calcium aluminate material are calcium dialuminate (CA2) and calcium hexaluminate (CA6), the calcium aluminate material contains a small amount of alpha-Al2O3 and basically does not contain calcium aluminate (CA), and the calcium aluminate material can be used in the fields of base catalysis or basic catalyst carriers such as hydrocarbon catalytic conversion, heavy oil pyrolysis-gasification coupling hydrogen production, ester exchange reaction and the like.

The application discloses a method for microwave sintering and resource utilization of aluminum ash, which comprises the following steps: mixing aluminum ash with part of calcium-containing raw materials (including quicklime and limestone) to obtain a ball-mixed mixture; mixing the ball-mixed mixture with the remaining calcium-containing raw materials and microwave-assisted heating materials, and then uniformly mixing, briquetting and drying to obtain briquettes; sintering the briquettes in a microwave field; and cooling and crushing the sintered product to obtain a calcium aluminate product. The method can not only obtain a high-quality calcium aluminate product, but also effectively remove salts and harmful elements such as nitrogen in the aluminum ash; harmful element fluorine is solidified into calcium fluoride in the calcium aluminate product and serves as a useful component of a steelmaking desulfurizer. The method realizes harmless and resource utilization of the hazardous waste aluminum ash, and is simple in operation and friendly to the environment.

An oxide ion-conducting solid electrolyte includes a mayenite-type compound having a representative composition represented by Ca12Al14O33, wherein the oxide ion-conducting solid electrolyte contains 1.5 mol% to 7 mol% of barium (Ba) in terms of oxide.

The application provides a method and system for preparing high-purity SiC through self-adaptive collaborative conversion of fluctuating fly ash silicon-aluminum ratio, comprising: adopting a differential acid etching technology for silicon-aluminum separation; performing differential acid treatment on high-silicon and low-silicon fly ash to efficiently separate silicon-aluminum components in the fly ash in an acid activation-ultrasonic mechanical chemical coupling mode; adopting a deep deterministic policy gradient algorithm to construct a temperature decision model for precise temperature control; establishing a temperature decision model, and optimizing a temperature rising path and a holding time based on the deep deterministic policy gradient algorithm; in-situ resource utilization of excessive Al2O3 in a low-silicon phase to prepare high-performance SiC; and converting the excessive Al2O3 in the low-silicon phase into a functional carrier that can be used for preparing a composite material through an in-situ chemical reaction. The acid activation-mechanical chemical coupling method is used to dissociate silicon-aluminum in fly ash, a dynamic optimization carbon thermal reduction path mode is fused with a reinforcement learning algorithm, and the two modes are coupled to improve the quality and efficiency of SiC material prepared from fly ash.