徐冷製鋼スラグ中のMg-Mnフェライトのキュリー点と脱燐との関係

抄録

The removal of phosphorus in steelmaking slags is essential for recycling such slags to the blast furnaces for recovery of theirmanganese, iron and lime contents. Phosphorus is mainly concentrated in the dicalcium silicate phase of the slags. Slow-coolingof steelmaking slags in an air atmosphere increased the grain sizes of constituent minerals, however, satisfactory magnetic separation results could not be attained because of the close association of a strongly magnetic ferrite phase with dicalcium silicate. The nature, distribution and Curie point of the strongly magnetic ferrite phase in the slow-cooled steelmaking slags were investigated and an attempt was made to separate the phosphorus-bearing dicalcium silicate phase in ground slag pulps heated to a temperature exceeding the Curie point. The effect of some impurities on the lowering of the Curie point of the ferrite was also investigated