Evolution Mechanism of Blast Furnace Cooling Plate Slag-Hanging Behavior with Different Cooling System Structure

Based on the 3D heat transfer numerical simulation model, the evolution mechanism of blast furnace cooling plate slag-hanging behavior with different cooling system structures is analyzed. Cooling plate reduced by 20 mm will not affect its slag-hanging behavior. Copper cooling plate is best suited for high heat load areas. The vertical spacing of cooling plate is extended by 200 mm, the uniformity of the slag layer decreases by 5%, and the temperature of cooling plate and refractory material increases by 11 and 50 °C. Cooling plate vertical spacing of 510 mm or less can ensure stable slag hanging in the blast furnace. When using a single refractory material, the average uniformity of the slag layer is 95%, 86%, and 79% for graphite brick, semigraphite brick, and sialon-SiC brick, respectively. Si₃N₄-SiC brick cannot operate properly in high heat load areas. The factory can consider setting 125 mm sialon-SiC brick in the furnace; graphite brick is used outside the furnace lining. The slag layer is well distributed, and the average value of uniformity is about 90%. Even if the slag layer is fully dislodged, the hot surface temperature of the furnace lining is 785 °C, and it can be quickly reslag hanging.