| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique which inhibits formation of coarse pseudo-grains with weak binding strength or ungranulated grains due to aggregation of fine grains and powder during granulation even when hard-to-granulate fine powdery iron ore, e.g. pellet feed, is used in large amounts and enables granulation of pseudo-grains of relatively uniform sizes.SOLUTION: A method of producing a granulation raw material for sintering includes a mixing step of adding water to a blending raw material containing at least fine powdery iron ore, a primary granulation step of granulating the blending raw material after the mixing in a primary granulator, a classification step of classifying pseudo-grains formed in the primary granulation, a disintegration step of disintegrating coarse grains produced by the classification, and a secondary granulation step of mixing the grains obtained by the disintegration with undersize fine grains and ungranulated powder produced during the classification and granulating the resultant mixture again to obtain secondary granulation grains. |
