What is high purity magnesite

High purity magnesia is one of the important raw materials of refractories. It is used for manufacturing various magnesia bricks, magnesia alumina bricks, ramming materials, charging materials and so on. Containing more impurities, used for paving the bottom of the steel furnace.

The main components of magnesia are magnesium oxide, and the impurities are CaO, SiO2, Fe2O3, etc. Magnesium oxide is an alkaline oxide with a melting point of 2800 degrees. After heating at high temperature, it is converted into a stable cubic crystal, commonly known as magnesite.

GB/T 2273-1998 Combine the national standards "magnesite" and "high-quality magnesite" into one standard "Sintered magnesite". Sintered magnesite is mainly made of magnesite, magnesite or magnesium hydroxide extracted from sea water after calcination at high temperature. Strong hydration resistance. CO2 is released when the magnesite is calcined at 700-950 ℃. The resulting magnesite is a soft porous loose substance and cannot be used as refractory. The magnesite calcined at 1550-1600℃ is called sintered magnesite. The burnt magnesite fired from natural magnesite is called sintered magnesite by using one-time calcining or two-step calcining process of high-temperature equipment such as vertical kiln and rotary kiln. Sintered magnesite is divided into 18 grades according to its physical and chemical indexes. See GB/T 2273-1998 for details. The magnesite which is formed after melting in an arc furnace is called electrofused magnesite. The magnesium oxide obtained from seawater is called seawater magnesia. High purity magnesite is produced by flotation purification of natural special grade magnesite through light burning, fine grinding, ball pressing and calcination in vertical kiln of ultra-high temperature oil. It is a brick, indeterminate refractory high quality raw material. Medium-grade magnesia is produced from light magnesia with MgO content of 97% by pressing ball and calcination in high temperature shaft kiln. With good sintering degree and dense crystallization, the product is a high quality raw material for middle-grade magnesia refractory products, and can also be used for manufacturing various magnesia bricks, magnesia alumina bricks, ramming materials, charging materials and so on. Containing more impurities, used to pave the bottom of a steel furnace.