Beware of mullite inclusion in coal

Uses of mullite: It is employed in industries such as refractory materials, ceramics, metallurgy, foundry manufacturing, and electronics. It features high heat resistance, high strength, low thermal conductivity, and significant energy-saving properties. It is suitable for use as lining materials in oil cracking furnaces, metallurgical hot blast stoves, ceramic roller kilns, tunnel kilns, electrical porcelain drawer kilns, glass crucible kilns, and various electric furnaces; it can come into direct contact with flames. After being tested by relevant technical supervision agencies, its performance meets the technical standards of similar products abroad. Introduction to mullite: Mullite is a high-quality refractory raw material, and this type of mineral is relatively rare. Mullite is a mineral that forms from aluminosilicates at high temperatures; it is created when aluminosilicates are heated artificially. Natural mullite crystals are elongated needle-shaped and form radial clusters. Mullite ore is used to produce high-temperature refractory materials. It is widely used as a thermal barrier coating in C/C composite materials. Mullite is the only stable binary compound in the AI2O3-SiO2 system at normal pressure, with the chemical formula 3Al2O3-2SiO2. Natural mullite is very rare; it is usually synthesized artificially through methods such as sintering or electrostatic precipitation. Chemical formula: A1xSi2-xO5.5-0.5x. Density: 3.16 g/cm3. Mohs hardness: 6–7. Refractoriness: stable at 1800°C, decomposes at 1810°C to form corundum and a liquid phase.

What’s the specific gravity of mullite? It seems to keep changing

Thanks for the reminder; I really hadn’t noticed it before!

How did the original poster collect those floating beads? Is what appears white on the filter press mullite?

We never paid attention to it here. . . . . . . . . . . . . . . . . . . .