34 results about "Calcium chromate" patented technology

The invention relates to a high-temperature wear-resistant repairing coating and a preparation method thereof, and the coating comprises a material A and a material B with a weight ratio of 70-85:30-15, wherein the material A is prepared by zirconia corundum fine powder, kyanite, aluminium titanates, silicon micropowder, magnesium zircon sand, alumina micropowder, pure calcium aluminate cement, sodium tripolyphosphate, fused calcium chromate, and zinc aluminate gahnite; and the B material is prepared by phosphoric acid, ink-grade aluminium hydroxide, aluminium chloride, yttrium-stabilized zirconium, borax, and a medium-temperature agglutinant. The product has excellent wear resistance, corrosion resistance, erosion resistance, thermal shock stability, and a high caking property; using the product, the running period of a circulating fluidized bed boiler is increased from about 3500 hours to over 18000 hours for accumulating running time; the problem that the boiler liner needs to be repaired and replaced frequently is overcome; human and material resources are saved; and the production efficiency is greatly improved.

The invention relates to a large blast furnace main iron runner castable, and belongs to the field of refractory castables. The large blast furnace main iron runner castable is prepared from, by weight, 5-8 parts of 8-5 mm chromium nitride, 15-20 parts of 5-3 mm chromium nitride, 10-15 parts of 3-1 mm sillimanite, 8-15 parts of 1-0 mm calcium chromate, 2-5 parts of partial clay powder, 3-7 parts of cobaltous oxide aluminum powder, 5-10 parts of cutting powder, 3-8 parts of amorphous graphite powder, 1-2 parts of composite charcoal powder, 0-3 parts of molybdenum trioxide powder, 3-5 parts of alumina micro powder, 1-5 parts of magnesium oxide iron powder, 1-3 parts of rho-aluminum oxide, 0-5 parts of electric smelting pure calcium aluminate cement and an addition agent, wherein the addition agent is prepared from, by weight, 0.1-0.2 part of calcium lignosulphonate, 0.01-0.05 part of nanometer potato powder, 0.01 part of malic acid and 0.1 part of C12H14N4O5S2. A blast furnace iron runner made of the castable has the advantages of being good in thermal shock resistance, high in corrosion resistance, large in iron exchanging amount and long in life.

The invention relates to a zero emission treatment method of completely turning chromium-containing waste liquor into useable resources. In the method, first enabling chromium-containing waste liquor to react with ammonia water to form ammonium chromate crystallized sediment; using sulphuric acid liquid to adjust pH value of mother liquor, then adding lime cream alkaline liquor to carry out neutralization reaction to generate cocrystallized sediment of calcium chromate and calcium sulphate; solid-liquid separating the liquid part and the sediment part; drying and dewatering the sediment part to obtain chrome yellow; adding ferrous sulphate to the liquid part to react and then carrying out atmospheric oxidation and solid-liquid separation to obtain the sediment part which is ferrite; carrying out filtration, concentration and cooling crystallization to respectively generate sodium sulphate crystallization and ammonium sulphate crystallization and then carrying out solid-liquid separation; drying and dewatering the sediment part and recovering the sodium sulphate and ammonium sulphate; mixing the liquid part and the liquid part before reverse osmosis membrance is filtered and then treating the mixture in recycling manner. The method of the invention not only features good commonality but also treats various conventional chromium-containing waste liquor; in addition, the method features easily controlled process conditions, simple equipment, easy realization of large-scale production, reduction of treatment cost, thus being a technology featuring reduction and decontamination for treating chromium-containing waste liquor as a usable resource.

The invention relates to a 318 high-temperature wear-resistant coating and a preparation method thereof, in particular to a rapid repair material for repairing various abrasive bricks and wear-resistant casting damage positions in circulating fluidized bed boilers of fuel electric plants. At the same time, the invention provides a method for producing the high-temperature wear-resistant coating, and belongs to the technical field of refractory material. The rapid repair material consists of a material A and a material B according to the weight portion proportion of 70-85 to 30-15, wherein thematerial A is prepared by zircon corundum, fine corundum powder, cyanite, yttrium-stabilized zirconium, silicon micropowder, alumina micropowder, pure calcium aluminate cement, trimeric sodium phosphate, and fused calcium chromate; and the material B is prepared by phosphorous acid, ink grade aluminum hydroxide, zirconia ultrafine powder, yttrium-stabilized zirconium, and fused calcium chromate.

The invention relates to a refractory material and a preparation method thereof, particularly a multielement high-strength wear-resistant composite paint and a preparation method thereof. The multielement high-strength wear-resistant composite paint is composed of a main material and an auxiliary material, wherein the main material is composed of fused alumina zirconia fine powder, kyanite, pure calcium aluminate cement, aluminium titanate, magnesium zircon sand, silicon micropowder, aluminum oxide micropowder, sodium tripolyphosphate, calcium chromate and gahnite; and the auxiliary material is composed of phosphoric acid, aluminum hydroxide for inks, aluminum chloride, boron-iron-molybdenum alloy, borax and agglutinant. The multielement high-strength wear-resistant composite paint provided by the invention has the advantages of high compressive strength, higher hardness, high Mohs hardness, high density, favorable wear resistance, favorable erosion resistance, favorable scour resistance, high thermal shock stability and high binding property. When being used for a circulating fluid bed boiler, the multielement high-strength wear-resistant composite paint prolongs the service life of the paint coat, reduces the repair frequency and lowers the maintenance cost.

The invention relates to a high-infrared-emissivity flexible calcium lanthanum chromate / silicon oxide composite fiber material and a preparation method and application thereof.The high-infrared-emissivity flexible calcium lanthanum chromate / silicon oxide composite fiber material is prepared through the following preparation method: (1) dissolving a silicon source and a chelating agent in a solvent A to obtain an inorganic precursor solution A, and then adding a spinning aid polymer to obtain a silicon oxide spinning solution; (2) dissolving a chromium source, a lanthanum source and a calcium source in a solvent B to obtain an inorganic precursor solution B, and then adding a spinning aid polymer to obtain a calcium lanthanum chromate spinning solution; (3) respectively putting the silicon oxide spinning solution and the calcium lanthanum chromate spinning solution into mutually independent spinning propulsion devices, and spinning on the same receiving roller to obtain composite gel nanofibers; and (4) drying and calcining the obtained composite gel nanofiber to obtain a target product. Compared with the prior art, the infrared emissivity of the composite fiber material is larger than 80%, and the composite fiber material can be independently used, and is good in flexibility, excellent in strength, easy to recycle and simple in preparation method.

The invention relates to a wet detoxification method for chromium slag and chromium-containing pollutants. The wet detoxification method comprises the following steps: screening and crushing the chromium slag and the chromium-containing pollutants, performing wet milling on the chromium slag and the chromium-containing pollutants in a ball mill, adding a filtrate containing sulfate ions, leaching out acid-soluble calcium chromate in chromium slag slurry, adding the chromium slag slurry and a first reducing agent sequentially into a reaction tank, stirring and mixing the chromium slag slurry with the first reducing agent to perform reduction reaction, reducing the acid-soluble calcium chromate in chromium slag slurry to trivalent chromium, adding concentrated sulfuric acid and to stirring and mixing for regulating, adjusting pH value of the chromium slag slurry to be 7+ / -0.5, then adding a second reducing agent into the reaction tank and stirring and mixing for reducing, stirring the reduced slag slurry to cure the reduced slag slurry, and converting hexavalent chromium in the chromium slag slurry to chromic hydroxide sediment; and separating solid and liquid of the cured chromium slag slurry. The wet detoxification method has the characteristics of low cost, no waste liquid, no slag returning phenomenon, good detoxification effect and capability of being applicable to the large-scale industrial production.

The invention relates to an epoxy resin antirust paint and a preparation method thereof, belonging to the technical field of polymer materials. The epoxy resin antirust paint of the present invention comprises the following raw materials in parts by weight: 40-60 parts of E-51 epoxy resin, 10-20 parts of polybutadiene, 100-200 parts of cyclohexanone, silane coupling 3-5 parts of aluminum stearate, 5-12 parts of aluminum stearate, 2-9 parts of calcium chromate, 5-19 parts of diatomaceous earth, 12-21 parts of zinc phosphochromate, 3-10 parts of potassium polymethacrylate , 30-50 parts of titanium dioxide, 10-20 parts of pigment, 30-50 parts of curing agent. The epoxy resin antirust paint of the present invention adopts E-51 epoxy resin, cooperates with other components, can solidify well at room temperature, and curing speed is faster, and according to the characteristic of functional coating, climate characteristic, anticorrosion coating construction The characteristics of the performance requirements meet the requirements of the validity period of the anti-corrosion protection.

The invention relates to the field of heavy metal recovery and treatment, and discloses a treatment process method of chrome slag. The method comprises the steps that: chrome slag is subjected to ball milling; the milled chrome slag is leached by using sulfuric acid, such that water-soluble sodium chromate tetrahydrate, calcium chromate, chrome calcium aluminate, basic iron chromate, chemically adsorbed hexavalent chromium, and dicalcium silicate-calcium chromate and iron calcium aluminate-calcium chromate which are hard to dissolve in water and can be dissolved in acid can be obtained by leaching. The reaction can be shown as: Ca2SiO4-CaCrO4+H2SO4+(x-1)H2O; CaSiO3.xH2O+CaCrO4+CaSO4, 4CaO.Al2O3Fe2O3-CaCrO4+H2SO4+(y-1)H2O; and CaO.Al2O3.yH2O+2CaO.Fe2O3+CaCrO4+CaSO4. A mixed material obtained by leaching is subjected to solid-liquid separation; a filter residue is washed by using water; solid-liquid separation is carried out again; a filtrate is delivered through an absorption exchange column loaded with a heavy metal absorption material; soluble chrome is absorbed and enriched in the surface of the heavy metal absorption material; backwashing and desorption are carried out, such that a concentrated chrome solution is obtained; and the solution is treated in a electrodeposition process, and chrome is recovered. With the technical scheme provided by the embodiment of the invention, highly toxic chromium element in the chrome slag can be removed, and heavy metal can be recovered and utilized. The method is beneficial for environment protection.

A high temperature abrasion resistant repairing paint and the preparing method thereof are provided. The high temperature abrasion resistant repairing paint consists of material (A) and material (B) at weight part ratio of 70-85:30-15. The material (A) consists of zirconium corundum fine powder, cyanite, aluminum titanate, silicon micropowder, magnesia zirconia, alumina micropowder, pure calcium aluminate cement, trimeric sodium phosphate, electrofused calcium chromate and gahnite. The material (B) consists of phosphoric acid, ink grade aluminum hydroxide, aluminum chloride, yttrium-stabilized zirconia, borax and middle-temperature sintering agent. The repairing paint has excellent abrasion resistance, corrosion resistance, crushing resistance, thermal shock resistance and good cohesive property. The operating cycle of circulating fluidized bed boiler can be increased from 3500 hours to more than 18000 hours accumulatively by using the repairing paint.

The invention relates to a zero emission treatment method of completely turning chromium-containing waste liquor into useable resources. In the method, first enabling chromium-containing waste liquor to react with ammonia water to form ammonium chromate crystallized sediment; using sulphuric acid liquid to adjust pH value of mother liquor, then adding lime cream alkaline liquor to carry out neutralization reaction to generate cocrystallized sediment of calcium chromate and calcium sulphate; solid-liquid separating the liquid part and the sediment part; drying and dewatering the sediment part to obtain chrome yellow; adding ferrous sulphate to the liquid part to react and then carrying out atmospheric oxidation and solid-liquid separation to obtain the sediment part which is ferrite; carrying out filtration, concentration and cooling crystallization to respectively generate sodium sulphate crystallization and ammonium sulphate crystallization and then carrying out solid-liquid separation; drying and dewatering the sediment part and recovering the sodium sulphate and ammonium sulphate; mixing the liquid part and the liquid part before reverse osmosis membrance is filtered and then treating the mixture in recycling manner. The method of the invention not only features good commonality but also treats various conventional chromium-containing waste liquor; in addition, the method features easily controlled process conditions, simple equipment, easy realization of large-scale production, reduction of treatment cost, thus being a technology featuring reduction and decontaminationfor treating chromium-containing waste liquor as a usable resource.

The invention relates to an industrial method for eliminating the toxic components of chromium slag, which comprises the following steps in turn: (1) countercurrently countercurrently countercurrently 1-2 times the chromium slag with 1-5‰ KMnO4 or NaClO2 solution, and simultaneously grinds the chromium slag to a particle size below 1mm; ( 2) Use 2 to 5 times of industrial water to wash the ground chromium slag in countercurrent in a spiral washing machine; (3) collect chromium slag, and use a conical hydraulic classifier and a hydrocyclone to separate the solid from the cleaning liquid; ( 4) Collect the cleaning solution, adjust the pH of the cleaning solution between 6-8, add saturated CaCl2 or BaCl2 solution until no precipitation occurs; (5) Collect the precipitate, and the resulting precipitate is calcium chromate or chromic acid Barium, the supernatant was recycled. The chromium slag detoxification process of the present invention not only eliminates Cr(VI), but also completely reduces total chromium, fully meeting environmental protection requirements.