The fly ash

useIn concrete mixed with fly ash to save a lot of cement and fine aggregate; Reduced water consumption; Improve the workability of concrete mixture; Enhance the pumpability of concrete; Reduces creep of concrete; Reduce hydration heat and thermal expansion; Improve the impermeability of concrete; Increase the decorative properties of concrete.National standard concrete: using high quality fly ash and high efficiency water reducing agent composite technology to produce high grade concrete of modern concrete new technology is developing rapidly in the country.GB 2 concrete: high quality fly ash is especially suitable for the preparation of pumping concrete, mass concrete, impermeable structure concrete, anti sulfate concrete and anti soft water erosion concrete and underground, underwater engineering concrete, compacted concrete and roller compacted concrete.National standard three concrete: fly ash concrete has the advantages of good workability, strong pumpability, improvement of finishing, impact resistance, frost resistance and so on.Fly ash is a kind of mixed material like volcanic ash formed after high temperature combustion. It is the power plant that burns coal to grind the coal into pulverized coal below 100 microns, which is sprayed into the furnace with preheated air into a suspended state of combustion, and produces high temperature flue gas mixed with a large number of non-combustible substances. Fly ash is obtained by collecting dust device. The chemical composition of fly ash is similar to that of clay. It is mainly used to produce fly ash cement, fly ash brick, fly ash silicate block, fly ash aerated concrete and other building materials. It can also be used as agricultural fertilizer and soil conditioner, recycling industrial raw materials and environmental materials.Application of fly ash in cement industry and concrete engineering: fly ash instead of clay raw material to produce cement, cement industry using fly ash ingredients can use the unburned carbon; Fly ash as cement mixing material; Fly ash produces low temperature synthetic cement. The principle of production is that the compound material is first cured by steam to generate hydrate, and then the cement mineral is formed by dehydration and low temperature solid reaction. Fly ash is produced without clinker cement, including lime fly ash cement and pure fly ash cement, lime fly ash cement is dry fly ash mixed with 10%-30% of quicklime or slaked lime and a small amount of gypsum mixed powder, or respectively fine and then mixed evenly made of hydraulic cementing materials; Fly ash mortar or concrete admixture, adding fly ash to replace partial cement in concrete or fine aggregate, can not only reduce cost, but also can improve the workability of concrete, improve impervious, carbamate, sulfate resistance and chemical corrosion resistance, reduce the hydration heat, improving the high temperature resistant performance of concrete, reduce particle separation and drainage phenomenon, reduce the shrinkage and cracking of concrete, and inhibition of stray current corrosion of steel bar in concrete.The application of the fly ash in building products: steamed fly ash brick, with power plant fly ash and lime or other alkaline exciting agent as the main raw material, also can be mixed with the right amount of gypsum, and adding a certain amount of coal cinder or water quenching slag aggregates, such as processed, stirring, digestion, grinding wheel, after pressing forming, atmospheric or high pressure steam curing and formed a kind of wall materials; Sintered fly ash brick, with fly ash, clay and other industrial wastes as raw materials, through raw material processing, mixing, molding, drying, sintering into bricks; Autoclaved production of foam fly ash insulation brick, fly ash as the main raw material, adding a certain amount of lime and foam agent, after batching, mixing, sintering molding and autoclaved into a new type of insulation brick; Fly ash silicate block is a wall material made of fly ash, lime and gypsum as cementing materials, coal cinder and blast furnace slag as aggregate, mixed with water, vibrated forming and steam curing. Fly ash aerated concrete is a kind of porous and lightweight building material which takes fly ash as raw material, adds quicklime, cement, gypsum and aluminum powder in proper amount, mixes with water and forms slurry, and then infuses the mold to steam and raise it. Powdered coal ash ceramsite, fly ash as the main raw material, mixed with a small amount of binder and solid fuel, after mixing, into balls, high temperature cultivation and firing system of a kind of artificial lightweight aggregate; Fly ash light heat insulation brick, is made of fly ash, burning stone, soft soil and wood chips for batching, with high thermal insulation efficiency, high refractoriness, small thermal conductivity, can reduce the furnace wall thickness, shorten the burning time, reduce fuel consumption, improve thermal efficiency, reduce costs.Fly ash as agricultural fertilizer and soil conditioner: fly ash has good physical and chemical properties, can be widely used in heavy clay, raw soil, acidic soil and saline soils, make up for the defect of their acid thin plate, the fly ash contains a lot of water soluble silicon calcium magnesium phosphate crops such as the necessary nutrition elements, it can make agricultural fertilizer use.Recovering industrial raw materials from fly ash: Recovering coal resources, using flotation method to add flotation agents in the ash water containing coal fly ash, and then using air flotation technology, so that coal particles adhere to the bubble floating and separation of ash slag; Recycling metal substances fly ash contains Fe2O3, Al2O3, and a lot of rare metals; Sort hollow beads, hollow beads have small quality, high strength, high temperature resistance and good insulation, can be used for plastic ideal filler, used for light refractories and efficient insulation materials, used in the petrochemical industry, used in the field of military, tank brake.Fly ash as environmental protection materials: using fly ash can produce molecular sieve, flocculant and adsorption materials and other environmental protection materials; Fly ash can also be used for fluoride wastewater treatment examples, electroplating waste water containing heavy metal wastewater and oily wastewater, the fly ash contained of Al2O3, CaO, such as active component, with production of fluoride complexes or have flocculation of colloid on fluorine ion, also contains zeolites, mullite, granular and silica gel, etc., with inorganic ion exchange and adsorption bleaching features.Fly ash can be used as production raw materials: fly ash is a kind of inorganic fire insulation board production raw materials, green inorganic fire insulation board raw materials for 70% ordinary cement,30% fly ashFly ash can be used as raw material for papermaking: in foreign countries, some studies take fly ash as a new raw material for papermaking, and analyze the principle of how fly ash can improve the tensile strength and internal bonding strength of paper through electron microscope.