2738 results about "Magnesite" patented technology

A non-oxide compound magnesite-graphite brick containing carbon less than 6% belongs to a fire resisting material. The material contains magnesia of 75-94%, carbon of 1-5%, non-oxide such as nitride and boride of 0.4-20%, additive of 0-5%, and binder containg carbon. Such magnesite-graphite brick with low carbon has a low heat conductivity, a small acierating to the molten steel and less pollution to the low carbon steel compared to the common magnesite-graphite brick. The magnesite-graphite brick has a good slag resistance because the magnesia is the primary component. And it also has a good heat shock capacity because the carbon is one of the primary components. The carbon prevents said non-oxide from being oxidated. The brick maintains a good heat and shock resistance and slag resistance when reducing the proportion of the carbon because said non-oxide has a low heat expansion and a wet resistance to the slag.

A process for mitigation of fouling deposits within a combustion zone, capturing of toxic metal emissions, and reduction of visible sulfur emissions attributable to sulfuric acid mist during coal combustion. SO₃ formed during coal combustion is reduced by the addition to the coal of raw, unprocessed magnesium-containing minerals such as magnesite ore or brucite ore. The minerals are pulverized to a fine particle size and combined with pulverized coal to provide a mixture of the particles. The mixture is combusted and the ore particles calcine and decrepitate to very fine magnesium oxide particles that have a significant particle surface area. The magnesium oxide particles react with the SO₃ produced during combustion of the coal and also capture toxic metals to reduce the quantity of undesirable stack discharge components.

The invention relates to an alkaline composite refractory brick, which consists of a periclase-magnesium aluminate spinel flame retardant coating and a periclase-forsterite thermal-protective coating. The proportion of the alkaline composite refractory brick is as follows: 1) the proportion of the flame retardant coating is as follows: 29 to 48 percent of magnesite of between 5 and 1 millimeter, 7 to 16 percent of the magnesium aluminate spinel of between 3 and 1 millimeter, 6 to 20 percent of the magnesite of between 1 and 0.088 millimeter, 0 to 4 percent of desilicated zirconia granules of between 0.4 and 0.088 millimeter, 16 to 25 percent of the magnesite of less than 0.088 millimeter, 0 to 10 percent of magnesite micropowder of less than 0.020 millimeter, 0 to 5 percent of desilicated zirconia micropowder of less than 0.020 millimeter, 0 to 3 percent of calcium carbonate micropowder less than 0.020 millimeter, 0 to 6 percent of lanthanum oxide of less than 0.020 millimeter, and 0 to 0.3 percent of additional water reducing agent (sulfonated naphthaldehyde polymer, sulfonated melamine polymer and polycarboxylic acid or sodium salt thereof); and 2) the proportion of the thermal-protective coating is as follows: 0 to 20 percent of the magnesite of between 3.2 and 1.0 millimeter, 35 to 45 percent of the forsterite of between 3.2 and 1.0 meter, 5 to 15 percent of the magnesite of between 1.0 and 0.088 millimeter, 5 to 15 percent of the forsterite of between 1.0 and 0.088 millimeter, and 30 to 40 percent of grinding powder of the magnesite and the forsterite of less than 0.088 millimeter. The material has the advantages that the material improves the erosion resistance of the flame retardant coating by micropowder technology, and allows the sintering temperature of the flame retardant coating to be matched with that of the thermal-protective coating, thereby producing the periclase-magnesium aluminate spinel alkaline composite refractory brick which has excellent.

The invention relates to a low-carbon corundum spinelle brick for refined steel ladles and a preparation method thereof for overcoming the defect of overhigh carbon content in the prior carbon-contained fireproof material technology. The low-carbon corundum spinelle brick for refined steel ladles comprises the following components in percentage by weight: 60-70 fused corundum particles, 2-6 fused magnesite particles, 10-20 fused corundum fine powder, 2-10 fused magnesite fine powder, 5-15 fused spinelle fine powder, 3-6 alpha-Al2O3 micro powder, 0-2.0 metal aluminum fine powder, 0-2.0 metal silicon fine powder, 2-6 bond, 1-2 superfine graphite and 2-6 titanium white powder. The invention has good thermal stability at high temperature, resists high temperature and the erosion of molten steel and slag and has high mechanical strength, good thermal shock stability and high under-load softening point, thereby being widely applied to various steel ladles, in particular to steel ladles of refined low-carbon steel and ultra-low-carbon steel.

The invention discloses a production method of an environment-friendly and energy-saving type regenerative magnesia-carbon brick, comprising the following production steps: (1) sorting and crushing waste magnesia-carbon bricks; (2) powdering with weak acid aqueous solution; (3) carrying out high-temperature drying to dehydrate and electromagentic resonance to homogenize; (4) carrying out crushing, particle shaping, iron removing and screening; (5) mixing materials: mixing regenerative aggregates, fine powder and newly-added and electrically-fused magnesite aggregates, and fine powder; and (6)forming. The mixed material is added with a bonding agent, is treated by high-speed constant-temperature mixing, hydraulic forming and electric heating drying and obtains a regenerative magnesia-carbon brick product. The production method solves the problem that the product in the prior art has unstable performance, can retain usable components such as electrically-fused magnesite, crystalline flake graphite and the like in the raw material furthest, has high recovery and utilization rate and is energy-saving and environment-friendly.

The invention discloses an air brick used for a magnesium and carbon ladle, and a producing method thereof, aiming at producing high-quality air bricks used for the ladles. The mass percentage of the chemical compositions of the air brick is: 55 to 99 percent of MgO, 0 to 20 percent of C, 0 to 20 percent of AI2O3, 0 to 5 percent of ZrO2, 0 to 5 percent of AI, 0 to 5 percent of AI-Mg alloy, 0 to 5 percent of CaB6, and 0 to 2 percent of B4; the physical property indexes are: volume density (g/cm<3>): 3.00 to 3.15, apparent porosity (%): 1.5 to 5.0, cold compressive strength (MPa): 40 to 65, and distortion resistance at high temperature (MPa): 14.0 to 25.0. Raw materials adopted by the invention comprise fused magnesite, magnesite clinker, crystalline flake graphite, corundum, zirconia and oxidation inhibitor. The raw materials are added into a pug mill and externally added with a bonding agent for mulling. Mulled pug is added into a mould, and molded by utilizing isopressing equipment or a friction brick press or a hydraulic press. The invention obviously reduces the apparent porosity of the air brick, not only can improve the basic slag corrosion resistant capability of the air brick, but also can reduce the cost of the raw materials by more than two thirds.

The invention provides a slag adhesion resistant gunning refractory for a converter. The gunning refractory comprises the following components in percentage by weight: 35 to 45 percent of magnesia carbon refractory crushed brick recycled aggregate, 5 to 16 percent of magnesite clinker, 18 to 25 percent of fused magnesite, 5 to 8 percent of silicon carbide, 8 to 13 percent of graphite, 1 to 3 percent of alumina cement, 1 to 3 percent of silicon micro powder, 1 to 3 percent of alpha-Al2O3 micro powder, and 3 to 4 percent of sodium hexametahposphate. On the basis of the raw materials, 0.2 to 0.4 percent of calcium lignosulfonate and 0.05 to 0.15 percent of polypropylene fiber are added; the magnesia carbon refractory crushed brick recycled aggregate has two granularities, namely comprises 30 to 40 weight percent of aggregate with the granularity of 3 to 1 mm and 60 to 70 weight percent of aggregate with the granularity of 1 to 0.15mm; the granularity of the magnesite clinker is 1 to 0.15mm; the fused magnesite has two granularities, namely comprises 40 to 60 percent weight percent of fused magnesite with the granularity of 180 meshes and 40 to 60 weight percent of fused magnesite with the granularity of 325 meshes; and the granularity of the silicon carbide is 180 meshes.

A method for separating and recovering nickel, cobalt, magnesium, iron and silicon from nickel-bearing laterite is disclosed; nickel, cobalt, magnesium and iron therein are leached out by using high-temperature peracid, leachate is pre-neutralized via serpentine powder, after the pre-neutralization, the leachate is neutralized by magnesite powder for de-ironing, and the scum is delivered for ironmaking after being dewatered by smoke gases in a fluidized bed furnace for making sulfuric acid, the de-ironed clear nickel liquid uses magnesite powder to precipitate nickel carbonate, and the precipitated liquid is concentrated and crystallized to obtain magnesium sulfate heptahydrate. The leached slag mainly contains silicon and can be used for making white carbon black. The invention can sufficiently recover and utilize nickel, cobalt, magnesium, iron and silicon in the nickel-bearing laterite, and the invention is simple in technology, low in energy consumption and pollution-free on environment.

The invention discloses an environment-friendly slow-releasing long-standing compound fertilizer which belongs to polyelement compound fertilizer and a production method thereof. The fertilizer comprises the following raw material ingredient (by parts by weight): 10-40 parts of powdered rock phosphate, 10-40 parts of potassium feldspar, 15-40 parts of coal gangue, 10-20 parts of magnesite powder, 10-30 parts of nitrogenous fertilizer, 8-18 parts of swell soil, 1-3 parts of kieselguhr and 0.3-1 part of trace element; the powdered rock phosphate, the coal gangue and proper amount of coke are roasted for 8-16 hours at 500-800 DEG C, cooled, crushes and screened by a 60-mesh sieve. The invention provides an environment-friendly energy-saving fertilizer capable of improving soil with comprehensive effective fertilizer composition, slow releasing and high fertilizer utilization ratio. Meanwhile, the environment-friendly slow-releasing long-standing compound fertilizer is suitable for various soils and growth of various crops and the preparation method thereof is provided. The problems of low fertilizer utilization ratio, environment pollution, hardening soil, high production cost and the like in the prior art are solved.

The invention discloses phosphate base cementing agent which is formed by uniformly mixing phosphate cementing mixture and water. The phosphate cementing mixture comprises the following component according to mass percent: 65 to 80 percent of phosphate cementing mixture and 20 to 35 percent of water; the phosphate cementing mixture comprises the following components according to mass percent: 20 to 60 percent of dihydric phosphate, 20 to 40 percent of magnesite, and 0 to 40 percent of inorganic mineral filler, wherein the mass of retarder occupies 5 to 15 percent of that of the magnesite; and the mass of sand occupies 0 to 30 percent of that of the phosphate cementing mixture. Phosphate gelling slurry can be served as structural adhesive to prepare fibrous composite material for concrete reinforcement, to improve the compatibility between the phosphate gelling slurry and concrete, and can also be served as gelling material to prepare artificial composite board material, self-leveling slurry, protective paint and the like.

The invention relates to a lightweight periclase-magnesium aluminate spinel refractory material for a rotary cement kiln and a preparation method thereof. According to the scheme, the preparation method comprises the following steps of: uniformly dispersing 0.2 to 4wt% of magnesite micro powder and 0.2 to 4wt% of active alpha alumina micro powder into 5 to 8wt% of binding agent to obtain a modified binding agent; adding 50 to 70wt% of porous periclase-magnesium aluminate spinel ceramic particles to a vacuum agitating machine; vacuumizing to be below 2.5kPa; maintaining the constant pressure for 3 minutes; adding the modified biding agent to the vacuum agitating machine; agitating for 10 minutes; closing a vacuumizing system; then adding 10 to 25wt% of porous periclase-magnesium aluminate spinel ceramic fine powder, 4 to 20wt% of fine magnesia powder, and 1.5 to 4wt% of magnesium aluminate spinel fine powder to the vacuum agitating machine; uniformly agitating; mechanically pressing and modeling; drying; and maintaining the temperature of 1,500 to 1,650 DEG C for 2 to 10 hours. The lightweight periclase-magnesium aluminate spinel refractory material for the rotary cement kiln has the advantages of being low in heat conductivity, high in intensity, high in thermal shock resistance, high in kiln coating performance, and high in resistance to medium erosion.

The invention discloses a ceramic tile capable of releasing negative oxygen ions and a preparation method thereof. The ceramic tile is prepared from the following raw materials in parts by weight: 38-56 parts of river sand, 22-34 parts of fluorite, 18-26 parts of volcanic, 10-20 parts of dolomite, 24-36 parts of modified clay, 15-25 parts of magnesite ore, 12-18 parts of tourmaline, 10-15 parts of hexacyclic stone, 8-14 parts of medical stone, 5-10 parts of stove ash residue, 6-12 parts of talcum powder, 4-8 parts of shell powder, 3-6 parts of barium carbonate and 2-4 parts of zinc oxide. The tourmaline, the hexacyclic stone, the medical stone and the like are added into the ceramic tile, so that the ceramic tile can release negative oxygen ions beneficial to human health for a long time, can obviously enhance blood circulation, promote metabolism, improve immunity and soothe mind and body, has an effect of bacteriostat and sterilization and has an obvious deodorization function, the indoor air can be purified, and the indoor air quality is improved.

The invention mixes and pre-extracts the mixed solution of acidic organic extractants such as P507, P204, C272, and naphthenic acid with magnesium bicarbonate and / or calcium bicarbonate solution and rare-earth solution. The rare-earth ions are extracted into the organic phase, then the loaded organic phase containing rare-earth ions are obtained through clarification, and can be used for the extract separation of the mixed rare-earth feed liquid. After a plurality of different levels of extraction, washing, stripping, single rare-earth compounds or rare-earth elements-containing enrichments can be obtained. The magnesium bicarbonate and/or calcium bicarbonate solution are prepared by roasting, digesting, carbonizing magnesite, limestone, calcite, dolomite and similar minerals, so that the content of impurities, such as silicon, iron, aluminum is lower. Ternary phase sediment is not produced in the pre-extraction and extraction separation process, so that the purity of the rare-earth products are not affected. The organic phase does not need ammonia saponification and does not produce ammonia-nitrogen wastewater. By adopting the invention, the production cost of rare-earth products is greatly lowered and the cost for three waste disposal is also greatly saved.

The invention provides a process for preparing lightweight magnesia-alumina spinel brick raw material, belonging to the production technique of fireproof materials. The process employs Gamma-Al2O3 fine powder and magnesite fine powder as main raw materials, the two are formulated according to the mass ratio of aluminum oxide and magnesium oxide of 2.7-4.0, and organic bond and water are additionally added to uniformly mix. By employing semidry process to mold, green bodies after being baked are calcined at a temperature of 1650-1800DEG C and then heat-insulated for 2-4 hours. The lightweight magnesia-alumina spinel brick raw material provided by the invention can be used for preparing heat-proof fireproof products and heat-proof amorphous fire-proof materials of magnesia-alumina spinel brick. Compared with the heat-proof corundum bricks, the heat-proof bricks prepared by employing lightweight magnesia-alumina spinel brick raw material have lower heat conductivity.

The invention discloses a low-temperature steel flux cored wire. Flux core of the flux cored wire comprises the following raw materials by weight percentage: 28 to 33 percent of rutile, 1 to 3 percent of aedelforsite, 14 to 18 percent of silicon-manganese alloy, 16 to 21 percent of ferrous powder, 2 to 4 percent of nickel powder, 1 to 2 percent of cryolite, 5 to 7 percent of feldspar, 1.5 to 2.5 percent of ferrotitanium, 0.5 to 1 percent of ferroboron, 5 to 6 percent of mid-carbon ferromanganese, 2.5 to 4 percent of magnesite, 4 to 6 percent of quartz and 1.5 to 3.5 percent of fluorite. Compared with the similar product of the prior art, the flux cored wire belongs to the meta-acid slag series, and has the advantages of good electric arc stability, less splash, easy slag removal, good low-temperature impact ductility, good low-temperature crack resisting performance, high efficiency and low cost.

The invention discloses high-viscosity continuous casting protective slag for solving slag inclusion on the surface of low-carbon steel. The protective slag comprises the following raw materials by weight percent: 0%-7% of glass powder, 50%-70% of premelting material, 5.5%-8.5% of fluorite, 4%-8% of dietary alkali, 3% of N330 carbon black, 3.5% of graphite, 0%-3% of R agent, 0.5-2% of lithium carbonate, 2%-5% of manganese carbonate, 2%-5% of magnesite, 3%-7% of bauxite, 1%-3% of cryolite, 1%-3% of adhesive, and 0.3%-1% of water-reducing agent. By utilizing the high-viscosity continuous casting protective slag, mainly on the basis of CaO and SiO2, a certain amount of fluxing agents such as the lithium carbonate, the fluorite, the dietary alkali and the like and a certain amount of carbon materials such as carbon black and graphite are externally added, thus the viscosity is improved and the surface tension is increased; and under the same technique condition, slag inclusion on the surface of a steel billet can be effectively prevented.

The invention provides a steam hot aerosol fire-extinguishing composite which contains 30-80wt percent of oxidant, 10-60wt percent of fuel additive and 2-30wt percent of cohesion solidification molding auxiliary agent. The oxidant can be one or more of the following substances: potassium salt, strontium salt, ammonium salt, magnesium salt, nitrocellulose and nitroglycerin; the fuel additive can be one or more of the following substances: azos, azoles, amino-guanidine nitrate, sodium bicarbonate, melamine, cyanoguanidine, carbamide, hexamine, triaminoguanidine nitrate, olefin, saccharose, aluminium powder, magnesite powder and magnesium-aluminium alloy power; the cohesion solidification molding auxiliary agent can be one or more of the following substances: phenol formaldehyde resin, ethoxyline resin, glycidyl azide, urethane rubber, hydroxyl-terminated polybutadiene, polyisobutylene, acetyl tributyl citrate, carboxymethyl cellulose, polyvinyl alcohol phenolic resin and acrylic resin. The invention also provides a fire extinguishing method and a fire extinguishing device adopting the composite. The invention has strong fire extinguishing capacity and fewer hazardous materials and can be applied to different places.

A method for preparing high-quality high ferrotitanium based on aluminothermic reduction and a device thereof belong to the technical field of metallurgy. The method comprises the following steps: (1) preheating an aluminothermic reducing agent into a liquid state; and ball milling and baking a titanium-containing substance, an iron-containing substance and a slagging medium, and then continuously adding an obtained mixture to a molten metal bath to perform high-temperature smelting; (2) blowing a particle reducing agent to perform smelting; and (3) cooling, obtaining ingot, removing impurities and obtaining the high-quality high ferrotitanium. The device comprises a charging device and a smelting device; the charging device comprises a charging hopper and a charging tube; and the smelting device comprises a resistance furnace, a magnesite bottom socket, a heat-resistant steel tube, a refractory material and a magnesite lining. The method has the advantages of short process, low production cost, low energy consumption, high product quality and the like, and the device has the advantages of simple structure, convenient operation and good application prospect.

The invention discloses a magnesite micro powder-assisting flame-resistant expanded halogen-free flame-resistant electronic wire-coated material and a preparation method thereof. The material consists of 100 parts of basic resin, 5-25 parts of compatilizer, 20-40 parts of fire retardant A, 10-30 parts of fire retardant B, 0-10 parts of fire retardant C, 5-25 parts of assistant fire retardant, 0-0.1 part of anti-dripping agent, 0.1-2 parts of lubricating agent and 0.1-1 part of antioxygen, wherein the fire retardant A is microcapsule-coated ammonium polyphosphate, the microcapsule takes phenolic resin as capsule wall, and the assistant fire retardant is modified micrometer-level magnesite micro powder. The material has good physical performance, does not obtain poisonous and harmful substances, does not release poisonous gas when burning, has good flame resistance, higher extension-resistant and breaking elongation ratio than congeneric products, higher flame-resistant effect than the congeneric halogen-free flame-resistant electric wire and cable material, greatly reduce the price, and particularly can be fast popularized in an industrialization way and applied in a marketization way due to the low price as high-grade magnesite resource is abundance in China.

The invention relates to a repairing mass for repairing in the converter production process of steel making and vanadium extracting of steel enterprises, in particular to a repairing mass used for a converter lining made of magnesia carbon bricks and a preparation method thereof, and provides a repairing mass having the advantages of short sintering time and long service life for meeting the requirement of production. The repairing mass per 100 weight parts comprises the following raw materials in parts by weight: 48-60 parts of fused magnesia, 22-28 parts of magnesite clinker, 10-16 parts ofmodified asphalt, 1-5 parts of metallic aluminum powder, 1-4 parts of ferric oxide powder and 2-10 parts of adhesive. The preparation method of the repairing mass is simple and convenient, i.e. all the raw materials are mixed. In the fettling production process of the vanadium extracting converter, when a local breakage appears on the converter lining, the repairing mass is coated on the part to be repaired; the repairing mass is sintered by utilizing the wall temperature of the converter, and production by blending with iron can be carried out after sintering; and under the conditions of lowsmelting temperature (1,360-1,400 DEG C) of the vanadium extracting converter and shorter smelting period (5-10 minutes), the repairing mass still can be quickly sintered with a working lining to form an organic combination with higher strength so as to prolong the service life of the repairing mass.

The invention discloses a corundum-spinel casting material for a dip pipe of an RH refining furnace, which is composed of a main material and an admixture, wherein the main material comprises the following components in percentage by weight: 35-60% of fused white corundum, 10-25% of fused compact corundum, 1-10% of fused magnesite powder, 1-10% of ultrafine spinel micropowder, 3-10% of active aluminum oxide powder, 3-10% of calcium aluminate cement group and 1-5% of zirconium oxide sol; and the admixture comprises an FDN water-reducing agent and explosion-proof organic fibers. Practice proves that the casting material is high in slag corrosion resistance and fine in thermal shock resistance and can effectively prolong the service life of an inserted pipe.

The invention relates to a high-performance magnesium-aluminum-chromium composite spinel brick for RH refining furnace dip pipes and non-ferrous smelting furnaces. The high-performance magnesium-aluminum-chromium composite spinel brick is characterized by comprising the following raw materials: 14.0-20.0 parts of low-chromium fused magnesium chromium sand (6-8% of Cr2O3, at least 78% of MgO), 71.6-82.0 parts of high-purity fused magnesite, 2.0-4.4 parts of nano Cr2O3 powder, 2.0-4.0 parts of uf-Al2O3 micropowder and 2-4 parts of binder. The manufacturing method comprises the following steps: mixing, molding, drying, firing and the like. The magnesium-aluminum-chromium composite spinel brick provided by the invention has the advantages of high sintering tendency, high crystal compactness, low porosity (at most 10%), high compressive strength (at least 100 MPa), high thermal shock stability (at least 18 times by 1100 DEG C water cooling) and the like. The Cr2O3 content of the product isat most 6%, thereby reducing the Cr2O3 content in the brick, lowering the production cost and finally effectively reducing the environmental pollution of waste magnesium-chromium bricks after use.

The invention relates to a mass eco-concrete expansive agent and a preparation method thereof. The method comprises the following preparation steps: sieving ores, pretreating, crushing to grind; using magnesite tailing and dolomite tailing to prepare raw material, mixing evenly, calcining at high temperature; and cooling in the air, and sieving to obtain the mass eco-concrete expansive agent. In the preparation method of the invention, CaO can be used as the early expansion source to compensate early shrinkage and overcome the defects of hydraulic concrete, namely high admixture and insufficient CaO; MgO can be used as the later expansion source to compensate later shrinkage; and magnesite tailing and dolomite tailing are combined reasonably to calcine, thus reducing and compensating the early and later expansions of hydraulic mass concrete.