| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of recovering iron and phosphorus which enables low-cost recovery of phosphorus and iron from steelmaking slag in recycling phosphorus-containing steelmaking slag, e.g. dephosphorized slag, and utilization of recovered phosphorus and iron as resources.SOLUTION: A method of recovering iron and phosphorus from steelmaking slag includes a step of reducing phosphorus-containing steelmaking slag with a reductant, e.g. carbon, Si or Al, excluding a reduction treatment in the presence of molten steel, to reduce iron oxides and phosphorus oxides in the steelmaking slag, dissolving the phosphorus produced by the reduction of the phosphorus oxides in the iron produced by the reduction of the iron oxides to recover a phosphorus-containing molten iron of a phosphorus concentration of 0.5 mass% or higher in a molten state and a step of subjecting the phosphorus-containing molten iron to a dephosphorization treatment by using a fluorine-free CaO-based flux to a concentration of phosphorus in the phosphorus-containing molten iron of 0.1 mass% or lower so as to cause phosphorus to be concentrated in the CaO-based flux as POin a concentration of 20 mass% or higher. |
