| Abstract Scope |
High-pellet-ratio operation in large blast furnaces reduces slag volume and weakens slag buffering capacity, making desulfurization highly sensitive to slag chemistry. In a 5500 m³ blast furnace, insufficient slag desulfurization became a key factor affecting furnace stability under high pellet charging conditions. This study applied high-MgO pellets to regulate the slag system by increasing MgO content and the MgO/Al₂O₃ ratio. The optimized slag composition improved the physicochemical conditions for sulfur transfer, helped maintain suitable slag fluidity, and reduced slag property fluctuations under low-slag-volume operation. Industrial practice showed that high-MgO pellet charging enhanced slag desulfurization, stabilized gas permeability and pressure-drop behavior, and supported smooth furnace operation. The results demonstrate that high-MgO pellets provide an effective burden optimization strategy for stable and efficient high-pellet-ratio operation in large blast furnaces. |