Making magnesia

According to the different sintering characteristics of raw materials and the technical requirements of magnesia products, one-step or two-step calcination process can be used in the production process of magnesia. For refractory raw materials, two-step calcination process is used to produce high purity and high density magnesia, and the main crystalline phases can be directly combined.

The one-step calcination process is as follows: raw material (magnesite ore with certain size requirement) calcination (coke or ashless fuel is used in shaft kiln or rotary kiln, calcination temperature is above 1600 C) product selection sintered magnesia. Due to SiO 2 pollution in coke ash, the content of SiO 2 in magnesia increases by about 2%.

The two-step calcination process is as follows: raw material (magnesite ore with certain size requirements or purified concentrate powder)light burning (in rotary kiln, suspension roasting kiln, multi-layer furnace, fluidized bed furnace or reverberatory furnace, using ashless fuel through about 1000 C (calcination) grinding fine magnesia (the higher the density of fine magnesia sand) calcination (using ashless fuel in shaft kiln or rotary kiln, the temperature is above 1800 C) Sintered magnesia.