METHOD FOR BLOWING DUST COAL FROM BLAST FURNACE TUYERE

PROBLEM TO BE SOLVED: To more largely blow dust coal of low quality having a high SiOin Ash without increasing hot pig iron [Si] in a blast furnace operation in which dust coal is largely blown from a tuyere.SOLUTION: Provided is a method for blowing the fine coal of a plurality of coal kinds from the tuyere of a blast furnace using two fine coal lances, in which installing is performed in such a manner that the positions of the tips of the blow pipes of the two lances are shifted before and after, and the concentration of an SiOcomponent in the Ash of the fine coal blown from the lance on the side of a furnace wall is higher than the concentration of an SiOcomponent in the Ash of the fine coal blown from the lance on the inside of the furnace. 【課題】 羽口から微粉炭を多量に吹き込む高炉操業において、溶銑[Ｓｉ]を増加させることなく、Ａｓｈ中ＳｉＯ２成分の高い低品質の微粉炭をより多く吹き込むこと。【解決手段】 高炉の羽口から複数の炭種の微粉炭を２本の微粉炭ランスを用いて吹き込む方法であって、２本のランスのブローパイプ先端の位置を前後にずらして設置し、炉壁側のランスから吹き込まれる微粉炭のＡｓｈ中のＳｉＯ２成分濃度が、炉内側のランスから吹き込まれる微粉炭のＡｓｈ中のＳｉＯ２成分濃度より高いことを特徴とする高炉羽口からの微粉炭吹き込み方法。【選択図】図２