| 摘要 |
PROBLEM TO BE SOLVED: To achieve a high desulfurization rate in a short time by a desulfurizing treatment of a molten pig iron with high desulfurization efficiency even in a situation where a facility modification with a large cost cannot be applied.SOLUTION: A 4 blades impeller 1, in which a sum D (mm) of a distance rbetween a blade upper outside position in a rolling forward direction and a central axis of the impeller, and a distance rbetween a blade lower outside position in the rolling forward direction and the central axis of the impeller satisfy the (1) formula:1.4≤D/h≤2.0 and the (2) formula:0.3≤D/L≤0.5, a first blade 2,2 having the distance rof A (mm) and the distance rof B (mm) and a second blade 3,3 having the distance rof B (mm) and the distance rof A (mm) are alternately arranged, and A and B satisfies the (3) formula:0.02≤(A-B)/(A+B)≤0.32, is used to set in a mechanical agitator. h is a height (mm) of a blade 2,3 of the impeller 1, L is a diameter (mm) of a molten iron surface in a pot and A>B. |
