Phase transition mechanism of high-silica fluxed pellets during consolidation

Abstract

An in-depth study of the consolidation behaviour of high-silica fluxed pellets will help promote the development of a high-proportion pellet smelting process suitable for China's resource structure. Lime, slaked lime, and limestone were used as calcium-containing additives to prepare high-silica fluxed pellets, and the suitable calcium-containing additives were lime and limestone. Compared with acid pellets, the suitable preheating temperature of high-silica fluxed pellets is higher (1100°C). The phase transformation during preheating consists mainly of the thermal decomposition of CaCO 3 and Ca (OH) 2 and the reaction between the solid phases.The roasting temperature of highsilica fluxed pellets should be controlled within a small range (1250°C-1280°C). The phase transition during the roasting of mainly lies in the generation and migration of the liquid phase. The Fe 2 O 3 consolidation, the pore distribution law, and the liquid phase formation jointly determine the consolidation properties of the pellet.