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Micro silica powder used in Several major fields

Micro silica powder used in Several major fields

Microsilica powder used in Several major fields

Anyang Weiyuan Alloy provides professional Micro silica powder information, high-quality products, and excellent delivery services.


Market Details

What is micro silica powder

Microsilica powder is a by-product of industrial smelting of metallic silicon and ferrosilicon alloys. It has excellent physical and chemical properties such as small particles, light weight, large specific surface area, strong volcanic ash activity, and high refractoriness. It has gradually transformed from industrial waste into an important Materials are widely used in concrete, cement, refractory and other industries.

The main component of microsilica powder is amorphous silica. The grade of silica determines the quality of the product, and the quality determines its economic benefits and application fields. To improve the economic added value and potential use value of microsilica powder, it is necessary to remove Impurities such as metal oxides and free carbon in microsilica powder improve the quality of silica.

Micro silica

Several major application fields of micro silica powder

1. Application in concrete industry

Concrete mixed with microsilica fume has the characteristics of high strength, good adhesion and cohesion properties, and can increase the molding thickness. In water conservancy and hydropower projects such as long-span bridges and offshore oil drilling platforms, microsilica fume concrete can improve its anti-seepage, anti-corrosion and anti-abrasion properties. During road construction, microsilica fume can greatly improve the early strength and wear resistance of concrete.

CHOI et al. studied the effect of microsilica dust on the properties of rapidly hardening polymer modified concrete. The results show that the strength of concrete increases with the increase of silica fume content. When 4% silica fume is contained, the strength reaches the maximum value. MEMON et al. mixed 10% microsilica fume into inorganic mineral polymer concrete and found that the tensile strength, compressive strength and flexural strength of the concrete increased by 12.8%, 6.9% and 11.5% respectively. Research by KIM and others has shown that with the incorporation of microsilica fume, the compressive and tensile strengths and elastic coefficients of energy-saving concrete gradually increase.


TANYILDIZI et al. proved that adding microsilica fume can prevent the decrease in the tensile strength of lightweight concrete at high temperatures. Gao Huiting and others mixed silica fume into concrete, which effectively improved the concrete’s impermeability, impact resistance, crack resistance, wear resistance, fatigue resistance and other properties. Liu Wenshen proved that adding microsilica fume can compensate for the shrinkage of bridge concrete, thereby improving the density of the concrete and strengthening its anti-cracking and impermeability properties. Guan Yao proved that microsilica powder can be better dispersed between the particles of precast box beam concrete, increasing the density of concrete. SHETTI et al.’s research results show that as the content of microsilica fume increases, the loss of early-aged concrete in acidic media decreases, while the loss in alkaline media remains basically unchanged.

Microsilica fume can improve the compressive, tensile, impact strength and wear resistance of concrete. This is because microsilica fume does not participate in the curing reaction, which improves the bonding strength and compactness between the components in the concrete and weakens the harm of Ca(OH)2. Microsilica powder and resin are easy to mix and difficult to agglomerate, which can effectively reduce precipitation and stratification. Microsilica dust can reduce the expansion and contraction rate of concrete, and has good insulation and arc resistance properties for concrete. Generally speaking, concrete mixed with microsilica fume does not react chemically with most acids and alkalis, thereby enhancing the corrosion resistance of concrete.

2. As a cement blending material

Some foreign countries use microsilica fume as an admixture for cement production. Canada requires that in cement mixed with microsilica fume, the silicon content in the microsilica fume should be >85%, while the burning loss should be <6%. In addition, the Soviet Union, the United States, Japan and other countries also use microsilica fume as a blending material to produce special cement. Special cement mixed with microsilica fume can be made into dense concrete with a strength 2 to 3 times that of ordinary concrete. It has good wear resistance, corrosion resistance, impermeability, insulation, frost resistance and resistance to chloride ions. Blocking performance, etc.

BHZAD et al. studied the impact of cement and microsilica fume precast panels on the engineering performance of peat block floors. They used the finite element method to analyze the stress distribution of the precast panels and peat floors. The results showed that the precast panels can significantly improve the strength and strength of soft peat floors. Carrying capacity. Zhou Min et al. [and Wang Xiuhong et al. added microsilica fume and polypropylene fiber to cement. The results show that adding the two can increase the strength, crack resistance, compactness, and durability of cement. However, the water absorption and volume of cement Quality will decrease. OZCAN et al. studied the effects of bentonite, fly ash and microsilica fume cement slurry on the uniaxial compressive strength of the matrix at 7, 14 and 28 days respectively. The study showed that microsilica fume is the most effective in improving the uniaxial compressive strength of the matrix. parameter indicators.

The strength of cement increases significantly with the increase in the content of microsilica fume. Microsilica fume can effectively improve the compactness and secant elastic modulus of cement, and significantly improve the corrosion resistance and creep properties of cement. However, the water absorption rate of cement and Volumetric quality will be reduced. Therefore, when incorporating microsilica fume into cement, attention should be paid to the reduction of water absorption and volumetric mass.


3. Application in refractory materials industry

Microsilica dust has excellent properties such as high refractoriness and is widely used in the refractory industry. It is mainly used to prepare high-temperature ceramics, ladle materials, high-temperature wear-resistant materials, breathable bricks, refractory castables, etc. Wang Tao et al. used microsilica powder to prepare high-purity porous mullite ceramics through pressureless sintering and gel injection molding processes at a mass ratio of Al2O3 and SiO2 of 3:2.5 and a sintering temperature of 1450°C. The compressive strength of and porosity are 260.93MPa and 21% respectively. It can be seen that microsilica powder can improve the fluidity, volume density and strength of refractory materials, improve the cohesion and high temperature performance of refractory materials, extend the service life of refractory materials, and achieve internal digestion and clean production of dust in ferrosilicon and industrial silicon smelting enterprises.


4. Application in metallurgical pellets


Some companies in North America also use silica and microsilica powder mixed pelletizing ore as raw materials for electric furnace reduction silicon smelting, and found that the silicon recovery rate is normal and the energy consumption per unit product remains unchanged. Norway’s Elkem uses water to moisten microsilica powder and form blocks into pellets of about 4cm, which can be directly reduced and smelted by electric furnaces without the need for roasting, drying, etc. The pellets can also be sintered at high temperatures. There are no problems such as bursting during the sintering process, and the product sinter has higher strength. A Russian company mixed microsilica powder and pulp waste liquid to make pellets and performed reduction and smelting in an electric furnace. The production proved that because the pellets are stronger than ordinary materials, they are not easily broken during transportation. A ferrochrome company in Northern Europe uses the microsilica powder slurry recovered from the wet method of electric furnace silicon smelting as a return silicon source, and mixes it with chromium ore to form pellets. The production shows that microcinnamon powder can enhance the cohesiveness of chromium ore pellets.

In the metallurgical industry, most companies use microsilica powder as a return material. Although this can reduce the environmental pollution caused by microsilica fume, it does not fully utilize the magical properties of microsilica fume. This is an extensive application. When utilizing it in metallurgy, more attention should be paid to its high value-added utilization.


5. Applications in chemical industry, composite materials, etc.


5.1 Preparation of nano white carbon black (nano SiO2)

At present, the market price of micro silica powder in my country is 1,200~1,500 yuan/t, while the market price of silica is 3,500~35,000 yuan/t. How to convert micro silica powder into silica efficiently and cheaply has become a research hotspot.

Zhang Deyi et al. used low-grade micro silica powder as the silicon source and prepared nano-SiO2 with a grade greater than 97% through the process of “acid leaching and purification-HF acid dissolution-hydrolysis-drying”. Its BET specific surface area and average particle size are 210m2/g respectively. and 90nm. Pei Xinyi et al. added microsilica powder to quicklime for calcination and then acid leached it to prepare white carbon black. They prepared white carbon black with a purity of 99.9%, an average particle size of 11.15 μm, and a whiteness of 96. Zhu Huixian et al. used micro silica powder and calcium oxide as raw materials, and prepared acidic silica sol with good stability through mixed acid and HF iron removal, high-temperature calcination and water dissolution. Yang Zhenwei uses micro silica powder with a grade of 93.05% as raw material, and undergoes steps such as burning at 600°C to remove carbon, hydrochloric acid pickling for preliminary impurity removal, HF dissolving glassy shell to remove impurities, HC1 and H2SO4 two-step cyclic acid leaching, and drying. Spherical nano-SiO2 with a purity of 98.3% was prepared. Wang Xiaoju used microsilica powder as the main raw material, increased the specific surface area of the micro silica powder through pickling, and combined it with binders, pore-forming agents, etc. to prepare a new adsorption material. Studies have shown that it has good adsorption properties.

Research on the use of microsilica dust to prepare silica mainly focuses on the preparation process, product purity and performance control. However, the product produced is precipitated silica, which has a large performance gap with the silica produced by the gas phase method. There are few research reports on the efficient conversion of soluble silicon by microsilica powder and the use of microsilica dust to prepare high value-added food-grade silica (vapor-phase silica).

5.2 Preparation of metallic silicon

BARATI et al. used microsilica powder with a grade of 97.5% as the silicon source and prepared metallic silicon through steps such as acid leaching, low-temperature calcination, magnesiothermic reduction, and acid leaching after reduction. The silicon content of the prepared metallic silicon is greater than 99%, and the B and P contents are less than 3g/t and 12g/t respectively. Its quality is better than metallurgical silicon, and it is a high-quality raw material for preparing solar-grade silicon. Therefore, using microsilica powder to prepare metallic silicon is an important direction for its high-value utilization.

5.3 Preparation of high-performance adsorbents

Micro silica powder has a large specific surface area and developed pores, and has strong adsorption effect. Zhu Wenjie synthesized MCM-41 mesoporous molecular sieve from purified micro silica powder. Its pore size is 2~5nm, which has a good effect on adsorbing and removing heavy metals. Yin Xia et al. used micro silica powder and lithium carbonate as raw materials and prepared lithium silicate adsorption materials through high-temperature calcination, which has good adsorption effect on CO2. Liu Junxia dissolved micro silica powder to prepare water glass. The hydrophobic silica gel synthesized through the sol-gel method can be used for adsorbing oil and gas recovery.

Since the adsorption materials prepared by micro silica powder have good adsorption effect on heavy metals, CO2, oil and gas, etc., it can be expected that the adsorption materials prepared by micro silica powder will be widely used in the treatment of waste water, waste gas, waste liquid, etc. Turning highly polluting dust into an efficient reagent for environmental control is a major innovation in the high-value utilization of micro silica powder.


5.4 Application in gel materials

Liu Xianghong mixed micro silica powder into calcium oxide and calcined it, and then used the acid-sol-gel method to obtain silicon aerogels with narrow particle size distribution and high purity. Luo Zhongkuan et al. used water glass as the silicon source and prepared silicon aerogel by adding acid-sol-gel method. Gao Ni et al. mixed asbestos fibers into water glass and prepared silicon aerogel through carbonization and drying, which has good strength and thermal insulation properties.

Since micro silica powder can be calcined at high temperature or dissolved in alkali to prepare water glass, high value-added utilization of micro silica powder can be achieved whether microsilica powder or water glass is used as the silicon source to prepare silicon aerogels. Silica airgel prepared from micro silica powder as a silicon source has high porosity, high strength, low density, good thermal insulation properties, and is non-toxic. It is expected to be widely used in aerospace, construction, medicine and other industries.


Micro silica powder company products for sale

Anyang WeiYuan Alloy Co., Ltd was established in 2011. We specialize in producing various ferroalloys for steel making, including Ferro Silicon, Ferro Chromium, Silicon Carbide, Ferro Manganese, Metal silicon price Calcium Silicon Barium, Metallurgy Nodulant, Silicon Calcium Powder, carbon raiser, etc.

Advanced equipment and strict QC procedures ensure our products are of high quality.

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