METAL/CHAR INTERACTIONS DURING PULVERISED COAL INJECTION IN A BLAST FURNACE

摘要

The dissolution of carbon from coal chars into liquid iron was seen to be influenced by more than the fusion point of the ash. Reactions between the ash oxides and the liquid iron influenced the level of carbon in the metal. Silica is seen to consume solute carbon from the liquid iron. The formation of an interfacial layer consisting of calcium and sulphur was seen to take place during iron/char contact, with a high degree of the interface being covered. The formation of the calcium sulphide layer can consume sulphur from the liquid iron. Further work is necessary to fully understand the role of ash composition on char dissolution into liquid iron, and the impact these reactions may have on blast furnace hot metal compositions. Knowledge of the ash reactions affecting carbon dissolution will allow better coal selection for PCI applications, with a view to maximising char consumption by blast furnace hot metal.