How harmful is silica fume to the body, and what is silica fume used for?

1. The median diameter is about microns), the specific surface area value is 15-25m2 g, and almost all the particles are 1um in size, and most of the world's silica fume belongs to this category. 2. The median diameter is left and right or below, and the specific surface area value is 30m2 g, which generally appears in high-purity silica fume. 3. The median diameter is here, and the specific surface area value is 5-15m2 g, which is relatively rare.

4. The median diameter is rare and the performance is poor. With conversion relationship: the unit of micrometer is m, the unit of nanometer is nm, and the conversion relationship is:

1 m (micron) = 1000nm (nanometer). The average particle size of the silica fume produced by Cypson is microns), which is only a few hundredths of the average particle size of cement, and can be well filled in the void of cement particles after being mixed with cement concrete, making the slurry more dense.

Control the segregation and water leakage of concrete materialsto reduce or avoid defects such as honeycomb, hemp surface, weak interlayer, cracks and milk skin in concrete.

Improve the compressive strength of concreteExperiments have proved that silica powder can greatly improve the strength of concrete.

Improve the durability of concreteto improve the impermeability, frost resistance, wear resistance and corrosion resistance of concrete.

Improve the charring resistance of concreteFor reinforced concrete, the injustice of silica powder can improve the bond strength between the matrix and the steel bar, and also enhance the corrosion resistance of the steel bar.

Improve the flow and density of refractoriesto improve the high-temperature strength and thermal shock of refractories.

The fineness specifications of silica fume required in the domestic and international markets are as follows:

Specification (2mm-10mm) Sieve allowance (weight).

500um-180um(30mesh-80mesh) +500um3% -180um10%.

425um-150um(40mesh-100mesh) +425um 5% -150um 15%.

250um-140um(60mesh-110mesh) +250um 3% -140um 10%.

125um-74um(120mesh-200mesh) +125um 3% -74um 10%.

74um (-200 mesh) +74um 5%.

45um (325 mesh) +45um 5%.

5um-1um(2500mesh-12500mesh) +5um 5%.

Because silicon metal is a hard and fragile material, the sieve residue can not be effectively controlled in the grinding process, and the phenomenon of over-grinding is serious, resulting in large product waste, high production cost, and product particle size is not up to standard, resulting in uncompetitive products.

As a highly effective active admixture, it can significantly improve the strength, impermeability, frost resistance and durability of concrete. The characteristics of silica fume concrete have been paid attention to, and silica fume concrete is widely used in water conservancy and hydropower projects, construction projects, highway projects and bridge projects.

There are many ways to make silicon powder from silicon blocks. Among them, the Raymond method, the roller method, the disc grinding method and the punching method are more effective and widely used. The equipment used is the Raymond method, the roller counter machine, the disc mill (also known as the vertical mill) and the punching method.

In terms of the principle of milling, the first three are extrusion and crushing, and the latter is impact crushing, which is very different from each other in terms of structure, each with its own characteristics, and each has its own advantages and disadvantages.

Application fields of silica fume

1. Used in mortar and concrete: high-rise buildings, harbor wharves, reservoir dams, water conservancy, culverts, railways, highways, bridges, subways, tunnels, airport runways, concrete pavements and coal mine roadway anchor spray reinforcement, etc.

2 In the materials industry:

1) High-grade high-performance low-cement refractory castables and prefabricated parts, the service life is three times that of ordinary castables, the refractory degree is increased by about 100, and the high-temperature strength and thermal shock resistance are significantly improved. It has been widely used in: coke oven, ironmaking, steelmaking, steel rolling, non-ferrous metals, glass, ceramics and power generation industries.

2) Large iron trenches and ladle materials, breathable bricks, coating repair materials, etc.

3) Application of self-flowing refractory casting materials and dry and wet spraying construction.

4) Oxide combined silicon carbide products (ceramic kiln furniture, flame insulation boards, etc.).

5) High-temperature calcium silicate lightweight thermal insulation material.

6) Electric porcelain kiln with corundum mullite push plate.

7) High-temperature wear-resistant materials and products.

8) Corundum and ceramic products.

9) Sialon combination products. In addition to being widely used in cast refractories, it is also widely used in electrofused and sintered refractories.

3. New wall materials and finishing materials

1) Polymer mortar, thermal insulation mortar and interface agent for wall insulation.

2) Cement-based polymer waterproofing material.

3) Lightweight aggregate insulation energy-saving concrete and products.

4) Putty powder processing for interior and exterior wall construction.

4. Other uses:

1) Portland brick raw material.

2) Production of water glass.

3) It is used as a reinforcing material for organic compounds. Because its composition is similar to that of silica produced by the gas phase method. It can be used as a filling reinforcing material in polymer materials such as rubber, resin, coating, paint, and unsaturated polyester.

4) Used as an anti-caking agent in the fertilizer industry.

Question: Do you use silica powder for wall tiles and floor tiles?

Silica fume has a wide range of uses and is often used in the chemical industry, electronic and electrical industries, etc.

1. Silica powder can reduce the peak exothermic temperature of epoxy resin when it produces curing reaction, so as to eliminate the internal stress of the cured object and prevent it from cracking;

2. Silica powder has strong corrosion resistance, is not easy to react with other substances, and its particles can also be evenly covered on the surface of the object;

3. Silica fume can reduce and eliminate precipitation and delamination, enhance the tensile and compressive strength of the solidified object, and improve the wear resistance of the object;

4. Silica fume is also used as a filler material and pozzolana material in concrete;

5. The treated silica powder has good wettability and adsorption to various resins, and is easy to mix;

6. Silicon powder is added to organic resin as a filler, which can not only improve the performance of the cured object, but also reduce the product cost;

7. Silicon powder is also often used in the production of various electronic and electrical products.

Product. Questions. How much is a ton of silica fume?

Dear, hello, the unit price of crystalline silicon powder is about 2,000 yuan, the molten silicon powder is about 5,000 yuan, and the spherical silicon powder is about 15,000 yuan.

Question: Do you use ordinary silica fume for making floor tiles and wall tiles?

Dear, it's not very useful.

Note that in addition to the above steps, there are also polishing and edging, segmentation inspection, packaging and other processes in the production of polished tiles, so that they can be truly completed.

Hope it helps.

Ask what are the uses of ordinary silica fume?

Silica fume can improve the performance of cement or concrete, and formulate special concrete with ultra-high strength (C70 or above), wear resistance, erosion resistance, corrosion resistance, penetration resistance, frost resistance, and early strength, which is used in dams, large reservoirs, hydropower, harbor terminals, railway bridges, highways, airport runways, tunnels and super high-rise buildings. At the same time, silica fume can also be used in the production of refractory materials and ceramic products to improve the strength and durability of products; It is used for paints, coatings, resins, rubber and other polymer material fillers, which can play a role in improving the comprehensive properties of materials.

Silica fume (also known as silica fume) is an amorphous, powdery silicon dioxide (SiO2) collected by a specially designed dust collector after oxidation of silicon vapor discharged from the flue gas during the smelting of ferrosilicon alloy or industrial silicon. The average particle size of silica fume is m and the specific surface area is 15000 20000m 2 kg, which has extremely strong surface activity.

It is a chemical product. We don't need it.

1. The biggest harm of silica fume to the body is silicosis. Caused by long-term inhalation of large doses of silica (Si02) dust. Silica dust enters the respiratory tract and is engulfed by lung macrophages, releasing active factors, which stimulate fibroblasts to synthesize more collagen.

2. Silica fume (microsilica or silicafume), also known as silica fume, scientific name"Silica fume", also known as silica fume, is made by the industrial electric furnace in the process of smelting industrial silicon and ferrosilicon at high temperature, and the smoke and dust escaping with the exhaust gas are collected and processed by a special trapping device. Scientific name"Silica fume", microsilica or silicafume, is an industrial electric furnace in the process of smelting industrial silicon and ferrosilicon at high temperature, with the exhaust gas escaping smoke and dust collected and processed by a special trapping device. In the escaping soot, the SiO2 content accounts for about 90% of the total soot, and the particle size is very small, and the average particle size is almost nanometer level, so it is called silicon powder.

Harmful silica fume needs to be properly disposed of to avoid environmental pollution. The treatment methods of harmful silica fume are:

1.Biodegradation method: Harmful silica fume is mixed into the organic substance, allowing it to naturally produce specific bio-silver sail degradable substances and release them safely into the environment.

2.Heat treatment method: the harmful silica powder is heat treated to completely decompose, and the harmful components are completely removed to meet the safety emission standard.

3.Impregnation method: Harmful silica powder is added with a specific solvent to make it no longer harmful by changing its form, so as to meet the requirements of safe discharge.

1.Biodegradation method: Harmful silica powder is mixed into organic matter, so that it naturally produces specific biodegradable substances and releases them safely into the environment.

2.Heat treatment method: The harmful silica powder is completely decomposed by the heat treatment of the forest chain, and the harmful components are completely removed to meet the safety emission standards.

3.Impregnation method: Harmful silica powder is added to a specific branch solvent to change its form to make it no longer harmful, so as to meet the requirements of safe discharge.

The importance of silicon to the biological world has not been recognized. In 1972, it was discovered that silicon is an indispensable element for the growth and development of chickens and rats. Later, the relationship between silicon and human health and disease has also attracted people's attention, and then it is considered to be one of the trace elements necessary for human beings.

Distribution and function of silicon, silicon is mainly concentrated in bones, lungs, lymph nodes, pancreas, adrenal glands, nails and hair. It is most abundant in aorta, trachea, muscle keys, bones and knotted tissues. Arterioles, corneas, and sclera are also quite high in content.

Tissue can contain hundreds of micrograms per 100 grams. Extremely low levels in brain tissue, possibly due to the blood-brain barrier preventing silicon from entering the brain. Silicon can also enter the fetus through the placenta.

Silicon is a component of collagen, elastic fibers, and extracellular amorphous junctions. Silicon is also found in various enzyme structures in subcellular structures. For more than a decade, silicon has been shown to be associated with the maintenance of normal growth and bone formation.

Silicon is one of the main components of osteoblasts and is involved in the calcification process of bone. For patients with osteoporosis, brittle nails, lung diseases, and slow growth, the amount of silicon in tissues can be reduced to 50% compared with normal.

The relationship between silicon and coronary heart disease has attracted people's attention. Silicon strengthens the elastic fibers of blood vessels, especially the intimal elastic layer, which acts as a barrier to inward lipid invasion. Therefore, the anti-atherosclerotic effect of silicon may be due to the fact that silicon prevents the formation of atherosclerotic plaques by maintaining elastic fibers and interstitial integrity.

As we age, the amount of silicon in various tissues gradually decreases. As the arterial walls harden, the amount of silicon within the tissue also decreases. Therefore, the reduction of silicon content can be used as a reference index for aging, which can be used to remind the elderly to strengthen health care and delay aging.

The anti-aging effect of silicon may be related to its changes in mucopolysaccharides.

The relationship between silicon and tumors is inconclusive. But one thing is certain, even if there is a cancer-causing effect, it is not the effect of silicon in food, but the action of silica dust.

Silica fume, also known as silica fume or condensed silica fume, is formed by the rapid oxidation and condensation of air when ferroalloy smelts ferrosilicon and industrial silicon (silicon metal) in the submerged thermal electric furnace, and the gas is rapidly oxidized and condensed with air after gas discharge. It is a by-product in large industrial smelting, and the whole process needs to be carried out with dust removal and environmental protection equipment, because the density is small, and it also needs to be encrypted with encryption equipment.

Silica fume has a great effect on concrete, can play a good role in its hardening function, mainly attributed to the improvement of interface layout and composition, the progress of the bond strength of the slurry and aggregate, and then eliminate the "weak connection" of different composite components in the concrete.

Silica powder concrete is used in water conservancy and hydropower projects, which can improve the anti-abrasion ability of the project. With the use of silica fume concrete, the impact abrasion resistance can be improved by about double, and the anti-abrasion resistance of the flow rate of 48m s can be improved by more than 3 times.

Silica powder concrete is used in water conservancy projects, which can improve the crack resistance function of the project. Silica fume concrete can improve the anti-penetration function and salt corrosion resistance, maintain steel bars, and the silica fume concrete is used in the repair of traffic highway pavement, with strong wear resistance.