Why does not recommend to use refractory fiber products in cement industry?

September 06, 2018

Why does not recommend to use refractory fiber products in cement industry?

Refractory fiber is a kind of insulating refractory material widely used in steel, ceramics and other industries. When used for a short period of time, the refractory fiber has a good heat insulating effect, but the heat insulating property of the refractory fiber is gradually deteriorated due to the pulverization of the fiber. More seriously, the pulverized fiber is harmful to the human body. Therefore, it is not recommended to use fiber insulation refractories in the cement industry.

The main problems of refractory fibers are thermal deterioration and environmental pollution. After heating, the amorphous fiber precipitates crystals, causing the fibers to shrink and pulverize. The first shrinkage of the fiber at 800~1000 °C is due to the enthalpy change of the aluminum silicate glass phase; the second time at 1200 ° C, the reason is remelting. After the addition of zirconia, the use temperature of the amorphous refractory fiber is increased. Refractory crystal fibers are used at higher temperatures. However, even at 1300 ° C, even the refractory crystal fiber is pulverized due to grain growth.

As the temperature increases or the atmosphere changes to a reduced state, the life of the refractory fiber is significantly reduced. In addition, water vapor, alkali or other volatile materials, as well as the scouring of the gas stream, can significantly shorten the fiber's useful life. After the fiber is pulverized, it becomes a fine needle-like substance that is easy to fly, and not only loses the heat insulating effect, but also causes discomfort to the human skin and the mouth, nose, and throat. The refractory fiber has been listed as a possible carcinogenic substance in the European Union. In the future, China may also legislate to regulate and limit the production and use of refractory fibers.