the effect of silica fume and its physical and chemical properties-pg电玩城

silica fume, namely: appearance of gray or gray powder, refractoriness > 1600 ℃. bulk density: 200 ~ 250 kg/m3. when ferro-alloys smelt ferro-silicon and industrial silicon (silicon metal), a large number of highly volatile sio2 and si gases are produced in the mineral thermal electric furnace. after gas discharge, they are formed by rapid oxidation, condensation and precipitation with air. it is a by-product of large-scale industrial smelting, and the whole process needs to be recycled with dusting environmental protection equipment, because the quality is relatively light, and also needs to be encrypted with encryption equipment.

specifications for

the chemical composition of silica fume is shown in the following table:

project sio2 al2o3 fe2o3 mgo cao nao

ph average 75 ~ 98% 1.0 0.9 / - 0.2% to 0.3% for 1.0 0.3 1.3 / - 0.1% 0.1% and 0.1% neutral

2. fineness of silica fume: the fineness less than 1um accounts for more than 80%, the average particle size is between 0.1 and 0.3um, and the specific surface area is 20 ~ 28m2/g. its fineness and specific surface area are about 80 ~ 100 times of cement and 50 ~ 70 times of fly ash.

3. particle morphology and mineral phase structure: during the formation process of silica fume, the amorphous spherical particles of the amorphous phase are formed due to the effect of surface tension during the phase transformation process, and the surface is relatively smooth. some of them are agglomerates where multiple spherical particles stick together. it is a very large specific surface area, highly active volcanic material. the tiny ball can lubricate the materials with silica fume.

silica fume effect: silica fume can fill the pores between cement particles, and at the same time, it can form gels with hydration products and react with alkaline material magnesium oxide to form gels. adding appropriate amount of silica fume in cement base concrete, mortar and refractory castable can play the following role:

1. significantly improve the anti-pressure, anti-folding, anti-permeability, anti-corrosion, anti-impact and anti-wear properties.

2. it can protect water, prevent segregation, bleed water and greatly reduce concrete pumping resistance.

3. the service life of concrete can be significantly extended, especially in the harsh environment such as chloride pollution erosion, sulfate erosion and high humidity, which can double or even multiple the durability of concrete.

4. substantially reduce the landing dust of sprayed concrete and castable, and increase the thickness of single spraying layer.

5. as a necessary component of high-strength concrete, c150 concrete has been applied in engineering.

6. with the effect of about 5 times of cement, the application in ordinary concrete and low-cement castable can reduce the cost and improve the durability.

7. effectively prevent the occurrence of concrete alkali aggregate reaction.

8. improve the compactness of cast refractories. when coexisting with al2o3, it is easier to generate mullite phase, so that its high-temperature strength and thermal shock resistance are enhanced.

gansu lixinyuan microsilica co., ltd. is a science and technology enterprise specialized in the research and development of high quality microsilica and related admixture. the company has established a number of production and processing bases in the main producing areas of silicon iron in northwest china and passed iso9001:2008 quality management system certification.

the company has achieved the production capacity of encrypted microsilica of 4000 tons per month, and cooperated with the professional logistics company to realize the rapid distribution and distribution of microsilica products. products has been widely used in the construction industry at home and abroad (large offshore, bridges, dams, water conservancy, oil field cementing), high performance concrete and other concrete products industry, the production of high strength refractory materials, ceramic products, insulation materials, grouting materials, paint, paint, resin, rubber, and other polymer filler, etc., in the industry establish a good reputation.