Effect of reduction conditions on structure and phase composition of blastfurnace charge composed of alkaline sinters and acidic pellets

The aim of this work was to examine the use of mixtures of high basicity or e sinters and acidic pellets in blast furnace charge. The proportion of hig h basicity sinters and acidic pellets depends on both the nature and basici ty of the latter and is used to obtain desired slag properties as well as s ufficient reducibility and mechanical strength of the furnace charge. Such an optimization of the composition of the charge brings a considerable cost reduction related to coke saving, elimination of fluxes and decrease in ai r pollution. The interpretation of reactions between high basicity sinters and acidic pellets in the 1130-1250 degrees C temperature range is possible on the basis of former separate results concerning sinters and pellets or constituent phases obtained synthetically: calcium- and magnesium-doped mag netite and wustite, olivines and calcium ferrites. Particular attention was paid to the conditions of formation of the phases. (C) 1999 Elsevier Scien ce B.V. All rights reserved.