Grecian Magnesite’s rotary kilns at Chalkidiki, north-east
Greece, which have a combined capacity of 420 tpd CCM and DBM
Grecian Magnesite
The main impurities of magnesite (MgCO3) are CaO, SiO2 and Fe2O3 but the most difficult to remove, in most hydrothermal ore types, are CaO and SiO2. All of the impurities are found in different mineral forms and this can affect the difficulty of recovering a high quality product with the techniques applied so far.
Gravity separation requires a distinguished difference in the density of the minerals to be separated; magnetic separation requires a difference in their magnetic susceptibility, while froth flotation demands a difference in their surface chemistry. An additional requirement is the liberation of the minerals to be separated.
CaO exists in the form of dolomite (Ca,Mg)CO3 and it does not differ substantially from magnesite in all these properties. SiO2 may exist in the form of serpentine xMgO.ySiO2.zH2O...