Analysis of Granulometry Influence on Magnesite Thermal Treatment

Magnesite is a basic raw material for carbonate industry. Its direct use for obtaining caustic and sintered magnesia after heat treatment is accomplished. The heat treatment of magnesia is carried out in shaft and rotary furnaces which are suitable for the materials with higher particle sizes and for deck furnaces for the materials with lower particle sizes. Currently new aggregates operating on the principle of compact thin layer and hydraulicmechanical fluidized layer are developed (Kostial 2005). Research, design, and operation of these devices are based on mathematical modeling. The basic factors affecting parameters of devices and the product quality include grain size of magnesite. The grain size affects the homogeneity of the heat treatment and thus its quality. In terms of adequacy of the model, the basic parameters are density, coefficient of heat transfer, heat exchange area and duration of the process. The contribution is aimed at determining the influence of granularity on homogeneity of the calcination and sintering process. Inhomogenity of grain size in terms of Shaft furnaces of SMZ, a.s. Jelsava theoretically represents