| 摘要 |
PURPOSE:To make possible the stable blowing of a large amt. of powder raw material by using a tuyere having a specific ratio of vertical and horizontal sizes as the tuyere to be used for blowing in the case of blowing powdery iron ore, steel making dust, etc. through the tuyere of a blast furnace into the blast furnace. CONSTITUTION:Iron raw material powders such as powdery iron ore and steel making dust are blown together with high-pressure hot wind through the tuyere 2 of the blast furnace 1 into the blast furnace by using a lance 3. The single tuyere 2 having the horizontally long elliptical or rectangular shape of 1:1- 1:20 the ratio between a vertical size and horizontal size or the tuyeres disposed with plural pieces of circular or square tuyeres in the horizontal direction are used for the tuyere 2. The blowing of a large amt. of the powder raw material is thus made possible without the unstability in the furnace condition that the melt 7 of the iron oxide powdery raw material blown into the furnace accumulates in the lower part of a tuyere raceway 4 and forms, together with coke 6, the mixed layer which is hardly flowable downward. |
