| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a vertical furnace which can be inexpensively operated with high productivity by using a solid raw material containing a large amount of blast furnace coke, and to provide a method for operating the same. <P>SOLUTION: This vertical furnace is a furnace for producing pig iron by charging an iron source having a high metal ratio of 95% or higher by average and a solid fuel containing 70 to 100 mass% of blast furnace coke in a layered form or a mixed form from the furnace top onto a bed of coke that has been charged in a lower part of the furnace, and melting the iron source by sending air through tuyeres in the lower part of the furnace; and sets (i) the distance from the lower face of the tuyere in the lowest stage in the direction of the furnace height to the upper face of the bottom plate of the furnace bottom is 0.7 times or longer of the furnace diameter at the position of the lower face of the tuyere, and (ii) the radiation heat of the furnace body per internal volume of the furnace in a height range from the shaft part to the bottom plate on the furnace bottom at 0.15 Mw/m<SP>3</SP>or less, which is calculated from the heat conductivities and thicknesses of lining refractories respectively applied onto a shaft part, a tuyere periphery, a wall portion on the furnace bottom side and the bottom plate on the furnace bottom. <P>COPYRIGHT: (C)2009,JPO&INPIT |
