What is the difference between medium-grade magnesite and refired magnesite

Medium magnesia is the main choice of raw material is 92% magnesium oxide content, magnesium oxide through the ball press, pressed into the ball. Pressed ball shape is 30mm, 30mm magnesium oxide ball is calcined in high temperature oil shaft kiln or coke kiln. The product produced by calcination is called medium-grade magnesia, which is mainly used to produce high-grade alkaline shaped or unshaped refractory materials, and the finished products are mainly used in metallurgy, building materials, nonferrous metals, chemical industry and other industries. In addition, middle-grade magnesia is used in metallurgy to produce metallurgical powder for bonding furnace bottom and wall, manufacturing slurry spraying lining, manufacturing magnesia brick and magnesia chrome brick. In addition to being used as the lining of furnace bottom, it is also widely used in electric steelmaking furnace, heating furnace, non-ferrous metal blowing furnace and rotary furnace.

The magnesite with 46% or more content is mainly used as the refractoriness of the magnesite, which is completely decomposed by Mg(CO3) when calcined in the shaft kiln at a high temperature to 1400 -- 1800℃ to form the cubic magnesite, which becomes the hard red-brown magnesite with high refractoriness. It is the ideal raw material for the production of unshaped refractory materials, products used for steelmaking open hearth furnace, electric furnace bottom and ramming lining.

It is made of natural special magnesite by flotation purification through light burning, fine grinding, ball pressing and ultra-high temperature oil calcined in shaft kiln. It is a brick, indeterminate refractory high quality raw material. It is produced by pressing ball and calcination in high temperature shaft kiln with MgO content of 97% as raw material. 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 for paving the bottom of the steel furnace.