Magnesia can be divided into fused magnesia, medium grade magnesia, high purity magnesia, and heavy burned magnesia.
Heavy burned magnesia is made from natural magnesite ore calcined in a high-temperature shaft kiln. Uses of heavy burned magnesia: raw materials for brick making and production of unshaped refractory materials, and finished products for steelmaking, electric furnace bottoms, and ramming furnace linings.
Electrofused magnesia is produced by melting selected grade A natural magnesite or high-purity calcined magnesium particles in an electric arc furnace. This product has high purity, large crystalline particles, dense structure, strong slag resistance, and good thermal shock stability. Therefore, the use of heavy electric fused magnesia is: it is an excellent high-temperature electrical insulation material, and is also an important raw material for producing high-grade magnesia bricks, magnesia carbon bricks, and amorphous refractory materials.
Medium grade magnesia is produced from lightly burned magnesium oxide with a MgO content of 97% by pressing balls and calcining in a high temperature shaft kiln. The product has good sintering degree and dense crystallization. The purpose of medium grade magnesia is: it is a high-quality raw material for producing medium grade magnesia refractory products.