| 摘要 |
[Problem] To provide an efficient method for operating a blast furnace with which an improvement in cooling power and an improvement in flammability are both seen alongside a lowering of the consumption rate of reducing agents, without making the outer diameter of a lance bigger, and a tube bundle-type lance used when this method is put into practice. [Solution] In a blast furnace operating method in which at least a solid reducing agent is blown into a furnace from a tuyère using a lance, a blast furnace operating method and tube bundle-type lance are provided in which, when only a solid reducing agent, both a solid reducing agent and a combustion-supporting gas, or all three of a solid reducing agent, a combustion-supporting gas and a gaseous reducing agent are blown into the furnace of the blast furnace at the same time, using a tube bundle-type lance in which a plurality of blowing-in tubes arranged in parallel are bundled together and housed within a lance main tube, the solid reducing agent, the combustion-supporting gas and the gaseous reducing agent are blown in via any of said blowing-in tubes. |
