| 摘要 |
PROBLEM TO BE SOLVED: To obtain raw material which is easily reduced and hardly reduction- powdered, by adding and mixing the original ore consisting essentially of primary hematite into pseudo grain obtd. by granulating mixed raw material composed of fine powdery ore and flux. SOLUTION: The mixed raw material of the fine powdery one having <50% the ratio of the grain having >=3 mm grain diameter and the flux of CaO, SiO2, etc. is charged into a granulating machine 1 to execute the granulation. CaO content of the granulated psudo grain is made to have >=14 wt.%. The granulated pseudo grain and the original ore consisting essentially of the primary hematite and the coarse grain one having >=50% the ratio of the grain having >=3 mm grain diameter is charged into a mixer 2 and mixed to produce sintering raw material. The reactivity with CaO is made further better by using >=10% easily melting ore of Robe river, etc., containing >=4% crystal water as the fine powery ore. It is desirable to use a hardly-melting ore of Carajas, etc., as original ore, and this ore is easily left as the original ore after sintering.
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