| 摘要 |
PURPOSE:To obtain pig iron having desired low Si concn. by controlling the reactivity of coke or a carbon material to be charged into a blast furnace to a low level to reduce the opportunity for the contact of gaseous SiO with metallic droplets. CONSTITUTION:In a coke packed bed close to a tuyere of a blast furnace, that is, a melting and dropping zone which becomes an Si shifting region, SiO is generated according to the formula when the coke is burned and when slag contacts with the coke. The amount of genrated SiO relates to a reactivity index according to a JIS method as shown by the figure. Coke or a solid carbon material with 15-20ml reactivity index is charged into a blast furnace. The generation of gaseous SiO in the Si shifting region is inhibited, and pig iron having desired low Si concn. is obtd. |
