| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing sintered ore with which a shatter index (SI) of≥90% can be maintained even when the content of components forming blast furnace slag is lower than that in the conventional case and also deterioration in reducibility index (RI) can be prevented. SOLUTION: A raw-material mixture, which is composed of an iron source raw material containing at least iron ore fines, a CaO-containing auxiliary raw material and a carbonaceous material, is mixed and moisture is added thereto to carry out pelletizing. Then the resultant pelletized material is fed to a sintering machine and the carbonaceous material is burnt, and the pelletized material is melted and cooled to manufacture sintered ore containing 4.0 to 5.0 mass% SiO<SB>2</SB>and 7 to 9 mass% CaO. In this process, first the iron ore fines having≤3.6 mass% SiO<SB>2</SB>content and a part of the carbonaceous material are preliminarily mixed and pelletized to form a preliminarily pelletized material, and then the outer periphery of the preliminarily pelletized material is coated with a part of the CaO-containing auxiliary raw material to form a coated preliminarily pelletized material. Successively, the coated preliminarily pelletized material and the rest of the above raw-material mixture are mixed and pelletized and then fed to the sintering machine. COPYRIGHT: (C)2007,JPO&INPIT
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