Furnace Slag: Metallurgy, Basicity Control, Process Performance, and Responsible Reuse
Furnace slag is a molten nonmetallic phase deliberately formed during ironmaking and steelmaking. It captures gangue, controls oxygen potential, protects metal, supports sulfur and phosphorus control, transfers heat, and interacts with furnace refractories. Blast furnace slag, basic oxygen furnace slag, and electric arc furnace slag are not interchangeable materials: composition, cooling route, mineralogy, free-lime risk, metallic iron content, density, particle size, and environmental testing determine their process value and potential downstream use.