Influences of Oxide Impurities Added to Calcium Carbonate on Characteristics of Sintered Calcium Oxide

摘要

CaO with superior thermal stability is broadly used as a raw material for unshaped refractories. The authors have been conducting a series of studies on CaO crystallite size and reported that, due to liquid phase formation of oxide impurity during the firing of heavy calcium carbonate at over 1300°C, sintering of CaO is promoted and CaO crystallite size is enlarged, resulting in retardation of dissolution rate". It is thought that CaO with high slaking resistance can be fabricated by controlling the amount of impurities. Physical properties (crystallite size, density, dissolution, etc.) of CaO sintered bodies, which were prepared by firing calcium carbonate containing added with impurities (Al_2O_3, Fe_2O_3, MgO), were examined.