(1) magnesite
There are two main types of magnesite in China: crystalline magnesite and amorphous magnesite.
Magnesite in China is mainly distributed in Liaoning and Shandong provinces, the main impurity of magnesite is talc, there are also some magnesite containing higher CaO, followed by dolomite, according to the chemical composition of Magnesite in China can be classified into S, ⅰ, ⅱ, ⅲ, ⅳ five grades, only S and I grade for calcination of brick magnesite.
High purity magnesia prepared by two-step flotation and two-step calcination can be used to develop many kinds of high performance refractory products.
(2) other magnesium-bearing minerals
In magnesia refractories, the main mineral composition of magnesia olivine products is magnesia olivine (2MgO·SiO2) and magnesite (MgO).
This product is characterized by strong resistance to molten iron oxide and better thermal shock stability than ordinary magnesia brick.
Peridotite and serpentine are the main raw materials for the production of such products.
Dolomite is magnesium carbonate (MgCO3) and calcium carbonate (CaCO3) double salt as the main component of refractory raw materials, its chemical formula is CaMg(CO3)2 or MgCO3 CaCO3, its theoretical composition is CaO3 0.41%, MgO2 1.87%, CO2 47.72%.
CaO/MgO = 1.39, hardness 3.54.
Dolomite in China is rich in raw materials, widely distributed and relatively pure.
Liaoning Dashiqiao area is rich in reserves.
Shandong, Hubei, Shaanxi, Guangxi, Gansu, Jiangxi, Anhui, Sichuan, Yunnan, Hunan and other provinces are rich in mineral resources.
This ore body is often symbiotic with limestone and magnesite.