1977 Volume 63 Issue 8 Pages 1252-1259
Mineralogical study of LD converter slags was carried out by means of microscopic, EPMA and X-ray examinations and three crystalline phases, namely (i) dicalcium silicate (ii) dicalcium ferrite (iii) spinel phase or ‘FeO’ solid solution were identified. Phosphorus was found to exist only in the solid solution of 2CaO·SiO2. The rapidly and slowly cooled synthetic slags of CaO-SiO2-FeOx system containing 5wt% P2O5 were also studied by the same method. The slag compositions with different primary phase area chosen in order to obseve the phosphorus-enriched phase. The results of the CaO-SiO2-Fe2O3 system indicate that silico-carnotite [5CaO·SiO2·P2O5] was formed and it changed to the fluorapatite [Ca5F (PO4) 3] when 5 wt% of CaF2 was added. On the other hand, in the system CaO-SiO2-‘FeO’, silico-carnotite was formed only in the Ca2SiO4 primary phase area.