Approaches to High-grade Sintered Magnesia from Natural Magnesite

摘要

It is hard to manufacture high purity,dense sintered-magnesia from natural magnesite in the prevailing process of calcining and sintering,for two reasons:a)impurity,and b)low sintering activity of coarse-grained magnesite.In this paper,95%MgO magnesite was used as the starting material and finally magnesia of high density(3.47 g/cm^3)and high purity(98%MgO)was obtained after the flotation purification and a three-step sintering process.An industrial scale of the beneficiation system of natural magnesite was introduced for magnesite purification.In lab experimental,the three-step sintering process was implemented by calcining,hydrating,re-calcining and sintering,which has proven the possibility of densified magnesia from natural magnesite.