Production and Application Status of Microsilica Fume in my country
Feb 10, 2023
Production and Application Status of Microsilica Fume in my country
my country's silica fume products are developing rapidly, and the gap with foreign countries in this field is narrowing. Scientific research achievements such as high-strength concrete, micro-silica fume sprayed concrete, composite reinforced density agent, silica fume mortar, and low-cement castables have passed the technical appraisal at the ministerial level or provincial and municipal levels, and have been applied in many projects. The effect is remarkable. Some applied technologies have approached or reached the level of foreign countries in the early 1980s.
At present, most industrial silicon factories can recover one ton of high-quality microsilica for every three tons of industrial silicon produced. One ton of microsilica can be recovered for every five tons of ferrosilicon produced. According to incomplete statistics, in 2004 my country's micro-silicon fume output reached more than 120,000 tons, most of which contained SiO2 below 90%.
The main use of my country's silica fume is also in the field of concrete and refractory materials.
Micro-silica fume concrete has been used in important projects such as the construction of high-rise buildings, anti-scouring wear, anti-leakage and other projects. As early as 1986, my country has applied silica mortar to the repair of Gezhouba sluice and the anti-seepage of 2000-3000m3 reservoirs. Seepage prevention of water conservancy and hydropower projects such as Three Gorges Power Station, Ertan Power Station, Zipingpu Power Station, Yellow River Xiaolangdi Power Station, Fujian Shuikou Power Station, Qinghai Longyangxia Power Station, Shanghai Yangpu Bridge, Hong Kong Tsing Ma Cross-sea Bridge, Jiangsu Lianyungang Timber Wharf, etc. And anti-erosion parts, as well as for high-strength anti-seepage projects such as Shanghai Huangpu River Cross-river Tunnel Project micro-silica fume concrete is also used for anti-sulfate, chlorate, anti-rust and durability of steel reinforcement projects, such as my country's coastal construction Micro-silica fume concrete such as underwater oil production platforms is used in railways and roads, such as the national key project Qinghai-Tibet Railway construction projects also use more micro-silica fume products.
Micro silica fume is mainly used in unshaped parts in refractory materials. The General Building Research Institute of the Ministry of Metallurgy of my country began to conduct research on low-cement castables in 1985, and passed the ministerial appraisal in 1988. It has been used in thermal equipment of Baosteel and Shougang, and some materials imported from Japan have been replaced by domestic materials. Calcium aluminate cement is used in low-cement castables and ordinary castables. After adding microsilica fume and high-efficiency water reducer, low-cement castables can not only save 50-70% of expensive aluminate cement, but also improve performance. Cement castables have been used in many projects so far, such as used in Baosteel blast furnace iron trench cover to replace the original Japanese imported castables, saving a lot of foreign exchange for Shougang 250 walking heating furnace and 430 heating furnace burner bricks for Shougang 500 kai The parts with severe erosion and wear of the billet heating furnace are used for the lining of the gas generator of the Research Institute of Nanjing Chemical Industry Company. The service life reaches 68 days, which is 10-20 times longer than the service life of the original corundum tube.
In recent years, under the vigorous promotion of some research institutions and product development institutions, micro-silica fume has gradually been applied in the fields of engineering plates, wear-resistant floors, coatings, and functional mortars.
In addition, the application of micro-silica fume in other fields has also made progress. For example, Shanghai Xinghuo Chemical Plant has applied micro-silica fume to the production of water glass, which can produce water glass with a modulus greater than 4 under the condition of simplifying the process. Water glass with a modulus above 4 is neutral and can be widely used in high-temperature spraying and steel casting. Shanghai Baosteel has used this water glass.
