| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for granulating a raw material to be sintered, which strongly granulates a raw material of iron ore, thereby improves air permeability in granulated substances which are sintered and consequently enhances productivity in sintering ore. SOLUTION: This granulation method comprises the steps of: producing a pseudo-granulated substance from a particulate substance, the raw material of iron ore containing a powdery substance and calcium carbonate, by using a first granulating device 10; and producing the granulated substance from the pseudo-granulated substance and the remainder of the raw material of the iron ore or another raw material of iron ore, by using the second granulating device 11. A mass ratio of the particulate substance to the powdery substance is controlled to 0.7 or more but less than 1.6. An amount of a porous material in the particulate substance is controlled to 30 to 90 mass% of the raw material of the iron ore. An amount of calcium carbonate to be charged into the first granulating device 10 is controlled to 5.0 to 10 mass% of a fine powder substance in the raw material of the iron ore, and an amount of the raw material of the iron ore is controlled to 10 to 50 mass% of the granulated substance. The granulation method further comprises the step of charging a dispersing agent of 0.01 to 0.1 mass% with respect to the raw material of the iron ore, and water in a total amount of an equivalent water content to be absorbed by the raw material of the iron ore and 2.5 to 4.0 mass% of the equivalent water content, to the first granulating device 10. COPYRIGHT: (C)2008,JPO&INPIT
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