Effect of water vapour on the interface reaction between carbon brick and molten iron in blast furnace hearth

ABSTRACT In the production process of blast furnace, the damage of cooler and tuyere sleeve and some operation problems often lead to ponding in the hearth. Steam will not only oxidize carbon bricks, but also lead to the falling off of solidification layer, which poses a great threat to the longevity of the hearth. By studying the influence of water vapour content change, the influence mechanism of water vapour on the interface between carbon brick and molten iron in blast furnace hearth is revealed. The results show that the entry of water vapour will isolate the molten iron and carbon brick, and oxidize in contact with the carbon brick, increase the ceramic phase, dissolve into the molten iron, destroy the carbon brick structure at the iron carbon interface, produce spalling, accelerate the destruction and falling off of the solidification layer, so as to reduce the service life of the blast furnace.