| 摘要 |
PROBLEM TO BE SOLVED: To provide a phosphate fertilizer raw material having high fertilizer effect while containing iron oxide and a manufacturing method therefor.SOLUTION: There are provided a phosphate fertilizer raw material containing CaO, SiO, POand iron oxide (in terms of Fe) of total 60% or more, having a basicity α represented by mass concentration ratio of CaO and SiOof 1.5 to 3.0 inclusive and containing POof 8 mass% to (-4α+23α-4) mass% inclusive and iron oxide in terms of Fe of 5 mass% to 25 mass% inclusive, the phosphate fertilizer raw material having a total of existing concentrations of one or more of Ca(PO)-CaSiOsolid solution, 5CaO SiOPOand 7CaO 2SiOPOof 28 mass% or more. A molten slag having the above composition at 1250 to 1400°C is cooled at 10°C/min or more till 600°C.SELECTED DRAWING: Figure 3 |
