Effect of fluxes on high iron and low silica sintering

Abstract

Burnt lime and serpentine were incorporated into the sinter mix to improve high iron and low silica sintering. Optimization of how to use burnt lime including dosage of burnt lime, moisture of sinter mix, hydrating and granulation time was performed. Evaluations of sinter characteristics including sinter mineralogy, reducibility, low temperature reduction degradation, softening and melting down properties were carried out. Compared with the results of traditional process in base case, the tumbling index (TI) is increased by 1.53%–2.33% through proportioning high ratio of burnt lime or adding serpentine in the sinter mix. It is shown that effective granulation, better permeability and improved high temperature reactivity in the sinter bed are achieved, resulting in an increase in 3.13%–5.10% calcium ferrite occurring in acicular and columnar shape and decrease in glass phase, and with the reducibility index(RI) being increased by 1.65%–3.25%.