China`s industrialization process and socio-economic level have been developing rapidly in the past 40 years with the reform and opening up. The percentage of the country`s GDP growth is largely a price that cannot be ignored. The biggest problem caused by the development of industrialization is Environmental issues. Therefore, the development and use of various clean energy and energy-saving and environmentally friendly materials are extremely important for adjusting the industrial structure and taking a green development path. Ceramic fiber, as a light-weight, high-efficiency thermal insulation and refractory material, can reduce the loss of heat energy and reduce the waste of resources in industrial production and other applications. It has been widely used in industrial, civil, aerospace, national defense and other fields , Insulated parts.
1. Development timeline of ceramic fiber:
① As early as 1941, the American Kabu Wilcox Company used natural kaolin clay and melted it into fibers by an electric arc furnace.
②In the late 1940s, two American companies produced aluminum silicate series fibers, which were first used in the aviation industry.
③In the 1950s, ceramic fibers were put into industrial production.
④In the 1960s, the United States developed a variety of ceramic fiber products and used them for industrial kiln wall lining.
⑤ In the 1970s, ceramic fibers were produced and used in China.
⑥In the 1980s, ceramic fiber application technology was rapidly promoted in China, but the main applicable temperature range was below 1000 ℃, and the application technology was relatively simple and backward.
⑦ In the 1990s, with the popularization and application of zirconium-containing fibers and polycrystalline zirconia fibers, the use temperature increased to 1000 ℃ ~ 1400 ℃, but due to product quality defects and backward application technology, the application field methods are limited.
⑧ Entering the 21st century, with the development and development of science and technology, various ceramic fiber materials have become common customers in refractory and high temperature applications, and are increasingly enriched and improved in quality and variety.
As can be seen from the timeline listed above, ceramic fiber production started late in China. It was only in the 1970s that it was successfully developed and mass-produced in Beijing Refractory Factory and Shanghai Refractory Factory, and the initial production of ceramic fiber products The technology is backward and the product type is single. Until 1984, Shougang Refractory Factory started from the CE company in the United States to introduce the resistance method spinning fiber-reinforced ceramic fiber needle felt blanket production line. China's multi-site refractory materials factory began to introduce foreign production lines and technologies, which changed the ceramic fiber production process, The situation of backward production equipment and single product. In the past 50 years, China's ceramic fiber industry has gone from scratch, from small to large, from more to less, from a single fiber cotton to fiber spraying, customer complaint rate, pouring and other forms of Secondary processing or deep processing products, from traditional cotton, blankets, felt products to fiber modules, boards, shaped parts, paper, fiber textiles, etc., gradually meet the use requirements of refractory ceramic fiber products in various industries.
2. Classification of ceramic fibers
3. Application of ceramic fiber in energy saving and environmental protection
3.1 Application as high temperature thermal insulation material
Ceramic fiber is a high-efficiency energy-saving thermal insulation material. The material itself has the characteristics of general fibers, and at the same time has the high temperature resistance, corrosion resistance and oxidation resistance that ordinary fibers do not have. More importantly, it avoids the brittleness of general refractory materials. To a certain extent, it replaces the traditional heavy refractory brick and is used as the wall lining material of industrial kilns. First, the thickness of the kiln is reduced by 1/2, and the quality is reduced by 60-80%. The furnace construction steel during kiln construction is saved by 30-50%, which not only saves the kiln construction cost, It also greatly reduces the load of the steel structure of the kiln, thereby prolonging the service life of the furnace body. Second, the use of lightweight, low thermal conductivity, low heat capacity fiber materials as the kiln wall can reduce the surface temperature of the kiln wall , Speed up the kiln heating rate, thereby reducing the energy consumption in the furnace temperature operation control, which has a very significant energy saving effect on the furnace startup and shutdown.
Therefore, the biggest advantage of the industrial kiln made of ceramic fiber as the kiln wall is energy saving.
3.2 Application as a filter material
Compared with the traditional granular filter material, the fiber filter material has a larger interface adsorption and can retain suspended matter; compared with the foam ceramic filter, it has a smaller pore size and higher filtration accuracy; compared with the organic fiber filter Better thermal stability, chemical stability and thermal shock resistance. Therefore, due to its high strength, good thermal shock resistance, and chemical resistance, ceramic fiber materials have been widely used in air purification, high temperature flue gas filtration, diesel exhaust microfiltration trapping, chemical filtration, and metal liquid filtration. . Ceramic fiber filter can be divided into ceramic fiber composite membrane material, ceramic fiber paper, ceramic net (cloth), ceramic fiber filter body. The manufacturing process and application range of each material are different, which greatly meets the requirements of various production scenarios for filtration standards. Ceramic fiber filtration technology can reduce atmospheric environmental pollution and human harmful factors in air purification, high temperature flue gas filtration, diesel engine exhaust microfiltration, and reduce the rate of waste products in metal liquid filtration and chemical filtration, and reduce the generation of invalid waste. Energy conservation and environmental protection play an important role.
3.3 Application as sound and sound insulation material
Ceramic fiber products are porous aggregates of fine fibers and have excellent sound absorption and sound insulation properties. First of all, because the fiber product itself has many tiny pores connected between the fibers, when the sound waves enter the fiber material and propagate inside, the viscous resistance of the air in the pores and the friction resistance between the fibers will Part of the sound energy is converted into heat energy to form losses. Secondly, when the air in the pores is compressed, the ambient temperature rises, and when it is sparse, the temperature decreases, and the heat conduction of the fiber will lose a part of the acoustic energy. The ceramic fiber has been mainly made into a cotton board product form as a sound-absorbing material. Except for the ultra-fine glass wool board and the slag wool board, the average sound absorption coefficient of all other ceramic fiber cotton boards is higher than 0.80. It belongs to high sound absorption material and has been widely used in industry, construction, transportation and other fields. It is a sound-absorbing product that is worth promoting in isolating noise pollution.
Although ceramic fiber products have played an important role in high-temperature industries and other fields, there is no perfect thing in the world, and its shortcomings cannot be ignored. The most prominent thing is that ceramic fiber materials are relatively soft and require protective materials. It is easy to cause dust and irritate the skin. There is also inhalability, which will cause certain harm to the ambient air and human body during the manufacturing process. In this respect, it is necessary to continuously improve the performance of the product without changing the excellence of the ceramic fiber itself in practice. "Removing the dross and extracting the essence" is the purpose of maintaining sustainable development of everything.