HIGH FURNACE OPERATION METHOD USING REDUCED IRON

• Main Authors: SATO HIROTAKA, SUNAHARA KOHEI
• Format: Patent
• Language: English; Japanese
• Published: 12.11.2015
• Subjects: CHEMISTRY; MANUFACTURE OF IRON OR STEEL; METALLURGY; METALLURGY OF IRON

PROBLEM TO BE SOLVED: To provide a high furnace operation method using reduced iron without increasing high temperature ventilation resistance even using reduced iron derived from ferrous dust.SOLUTION: There is provided a high furnace operation method by preparing a mixture by mixing a reduced iron manufactured by heating, reducing and molding iron-based dust and having an iron content of 50.0 mass% or more, a gangue ratio ((CaO+SiO+AlO+MgO)/Fe) of 0.30 to 0.60 and a basicity (CaO/SiO) of 2.0 or more with acidic bulky ore and adjusting the iron content to 50.0 mass% or more, the gangue ratio ((CaO+SiO+AlO+MgO)/Fe) to 0.32 or less and the basicity (CaO/SiO) to 1.0 to 2.0, and injecting the mixture into the high furnace. 【課題】鉄系ダスト由来の還元鉄を使用しても、高温通気抵抗が上昇しない還元鉄を用いた高炉操業方法を提供すること。【解決手段】鉄系ダストを加熱・還元・成型して製造した還元鉄であって、前記還元鉄は、鉄分が５０．０質量％以上、脈石比（（ＣａＯ＋ＳｉＯ2＋Ａｌ2Ｏ3＋ＭｇＯ）／Fe）が０．３０以上０．６０以下、塩基度（ＣａＯ／ＳｉＯ2）が２．０以上であり、前記還元鉄と酸性塊鉱石を混合して、鉄分が５０．０質量％以上、脈石比（（ＣａＯ＋ＳｉＯ2＋Ａｌ2Ｏ3＋ＭｇＯ）／Ｆｅ）が０．３２以下、塩基度（ＣａＯ／ＳｉＯ2）が１．０以上２．０以下に調整した混合物を作成し、前記混合物を高炉に装入することを特徴とする高炉操業方法。【選択図】図１