In the past industrial production, fly ash was often directly discharged as industrial waste, which not only caused great pollution but also wasted resources. Since the advent of the Raymond roller mill, Fly ash ultrafine crushing has played an increasingly important role in the cement industry, concrete engineering, construction industry, and environmentally friendly materials. At present, fly ash is mainly used to produce fly ash cement, fly ash bricks, fly ash silicate blocks, fly ash aerated concrete and other building materials. It can also be used as agricultural fertilizer and soil conditioner, recycling industrial raw materials and making environmental materials, there are roughly hundreds of uses for fly ash. Now I will introduce the main uses to you.
1. Application of fly ash in cement industry and concrete engineering
Fly ash replaces clay raw materials to produce cement. It is a hydraulic cementitious material made by grinding Portland cement clinker and fly ash with an appropriate amount of gypsum. The cement industry uses fly ash as ingredients to utilize the unburned carbon; Fly ash is used as cement mixture material; fly ash is used to produce low-temperature synthetic cement. The production principle is to steam curing the batch materials to form hydrates, and then form cement minerals through dehydration and low-temperature solid phase reaction; fly ash is used to make clinker-free cement. It includes lime fly ash cement and pure fly ash cement. Lime fly ash cement is made by mixing dry fly ash with 30% quicklime or slaked lime and a small amount of gypsum, grinding them, or finely grinding them separately and then mixing them evenly. Hydraulic cementitious materials; fly ash is used as an admixture for mortar or concrete. Adding fly ash to concrete to replace part of the cement or fine aggregate can not only reduce costs, but also improve the workability and durability of concrete. Water permeability, gas resistance, sulfate resistance and chemical attack resistance, reduce the heat of hydration, improve the high temperature resistance of concrete, reduce particle separation and water separation, reduce the shrinkage and cracking of concrete, and inhibit the impact of stray current on the steel bars in concrete of corrosion.
2. Application of fly ash in building products
Steamed fly ash bricks use power plant fly ash and quicklime or other alkaline activators as the main raw materials. They can also be mixed with an appropriate amount of gypsum, and a certain amount of coal slag or water-quenched slag and other aggregates, and are processed and stirred. A wall material formed after digestion, wheel rolling, pressing and normal pressure or high pressure steam curing. Sintered fly ash bricks are made from fly ash, clay and other industrial waste materials, and are made into bricks through raw material processing, mixing, shaping, drying and firing. Foamed fly ash insulation bricks are produced by autoclaving. They use fly ash as the main raw material, add a certain amount of lime and foaming agent, and are a new type of insulation brick made through batching, stirring, injection molding and autoclaving. Fly ash silicate block is a wall material made of fly ash, lime, gypsum as cementing materials, coal slag, blast furnace slag, etc. as aggregates, mixed with water, vibrated to form, and steam cured. Fly ash aerated concrete is a porous lightweight building material made from fly ash as raw material, adding appropriate amounts of quicklime, cement, gypsum and aluminum powder, adding water to stir to form a slurry, and then pouring it into a mold and steaming it for curing. Fly ash ceramsite is an artificial lightweight aggregate made from fly ash as the main raw material, mixed with a small amount of binder and solid fuel, mixed, pelletized, and fired at high temperature. Fly ash lightweight heat-resistant insulation bricks are made of fly ash, burnt stone, soft soil and wood chips. They have high thermal insulation efficiency, high refractoriness and low thermal conductivity. They can reduce the thickness of the furnace wall and shorten the furnace wall. Firing time, reduced fuel consumption, improved thermal efficiency, reduced costs.
3. Fly ash is used as agricultural fertilizer and soil conditioner
Fly ash has good physical and chemical properties and can be widely used to transform heavy clay, raw soil, acidic soil and saline-alkali soil to make up for its acid, thin and sticky defects. Fly ash contains a large amount of citrus-soluble silicon, calcium, magnesium, phosphorus and other crops. Necessary nutrients, so it can be used as agricultural fertilizer.
4. Recycling of industrial raw materials
To recover coal resources, use the flotation method to add flotation agents to the slurry water containing coal fly ash, and then use air flotation technology to make the coal particles adhere to the bubbles and float up to separate from the ash. Recycled metal substances Fly ash contains Fe2O3 AI2O3 and a large amount of rare metals. Sorting hollow microbeads. Hollow microbeads have small mass, high strength, high temperature resistance and good insulation. They can be used as ideal fillers for plastics, lightweight refractory materials and efficient insulation materials, and are used in the petrochemical industry, military industry, tank brakes.
5. Make environmentally friendly materials
Fly ash can be used to manufacture environmentally friendly materials such as molecular sieves, flocculants and adsorbent materials. Fly ash can also be used to treat fluorine-containing wastewater, electroplating wastewater, heavy metal-containing wastewater, and oil-containing wastewater. Fly ash contains active components such as AI2O3 and CaO, which can produce complexes with fluorine or produce products that have a flocculation effect on fluorine. Colloidal ions also contain zeolite, mullite, carbon particles and silica gel, etc., which have inorganic ion exchange properties and adsorption and decolorization effects.
The application of fly ash is inseparable from the help of grinding equipment. Guilin Hongcheng is a manufacturer of Fly ash ultrafine crushing grinders. Our vertical mills, Raymond roller mills and other equipment provide good opportunities for the production of fly ash. If you have relevant needs, please leave us a message to learn more about the equipment details.