Thermodynamic Study on Modification of Converter Slag by Using Hot Blast Furnace Slag

Abstract

Blast furnace slagBlast Furnace Slag (BFS) andConvert converter slagConverter Slag (CS) are the main by-products of the BF-BOF long-process steel production model. In China, the utilization ratio of BFSBlast Furnace Slag is high. CSConverter Slag cannot be widely used in the building materials industry due to its characteristics, which is an important issue for the sustainable development of Chinese steel companies. In this article, FactSage software is used to study the conversion of CSConverter Slag by using the heat of BFSBlast Furnace Slag, and the research results provide a theoretical basis for improving the utilization ratio of CSConverter Slag. The thermodynamicThermodynamic calculation results show that when the temperature is lower than 1200 ℃, the liquid phaseLiquid phase ratio of the CSConverter Slag is higher than that of the BFSBlast Furnace Slag. When the temperature is higher than 1250 ℃, the liquid phase ratio of BFSBlast Furnace Slag is much higher than that of CSConverter Slag. When the mass ratio of BFSBlast Furnace Slag to CSConverter Slag is increased from 5:5 to 9:1, the liquid phaseLiquid phase ratio of the mixed slag at the same temperature will gradually increase. The molten BFSBlast Furnace Slag can absorb the free CaO and MgO in the CSConverter Slag through a variety of eutectic phase and peritectic phase melting reactions, and melt part or all of the high melting point Ca2SiO4. When the proportion of BFSBlast Furnace Slag is relatively high, the fluidity of the mixed slag can be maintained, which provides a guarantee for subsequent processing.