A New Net Red in Refractory Industry -- Origin of Magnesia

What is magnesia?

Magnesite is calcined from magnesite, bischofite or magnesium hydroxide extracted from seawater at high temperature. It is a general name for the products of magnesite and other magnesia raw materials that have been treated at high temperature to reach the sintering process. Magnesia produced by burning natural magnesite with one-step or two-step burning process using high-temperature equipment such as shaft kiln and rotary kiln is called sintered magnesia; Seawater magnesia is made by extracting magnesium oxide from sea water after magnesite and other raw materials are melted in an electric arc furnace and cooled. Building material grade magnesium oxide

Magnesia is one of the important raw materials of refractories. It is used to manufacture various magnesia bricks, magnesia alumina bricks, ramming materials, furnace mending materials, etc. The ones with more impurities are used to pave the bottom of the steelmaking furnace.

The high-purity magnesite is calcined in a super high temperature oil shaft kiln by using natural super grade magnesite ore for flotation purification and light burning, fine grinding and ball pressing. It is a high-quality raw material for brick making indefinite refractory.

Medium grade magnesia is produced from light burned magnesia with 97% MgO content by pressing ball and calcining in high temperature shaft kiln. The product has good sintering degree and dense crystal. It is a high-quality raw material for producing medium grade magnesia refractory products.

Electric fused magnesia is made by melting selected special natural magnesite or high-purity light burned magnesium particles in an electric arc furnace. This product has the characteristics of large crystal grain, compact structure, slag resistance, and good thermal shock stability. It is an excellent high temperature electrical edge material and an important raw material for making high-grade magnesia bricks, magnesia carbon bricks, and amorphous refractories.

Raw materials for magnesia production

The main raw material for producing magnesia refractories is magnesia, which refers to sintered magnesia with particle composition. It is broken from sintered magnesite. Sintered magnesite can be obtained by calcining magnesite.

In addition, sintered magnesite can also be extracted from seawater, salt lake brine, dolomite, serpentine and brucite. But so far, sintered magnesite in China is mainly obtained by calcining natural magnesite, and the magnesium extraction project in salt lake is still under construction.

The production of fused magnesia in China is mainly concentrated in Liaoning and Shandong, which are mainly magnesite.