| 摘要 |
PROBLEM TO BE SOLVED: To produce molten pig iron at a low coke ratio in a specified vertical melting furnace.SOLUTION: When ferrous scrap, iron-containing dust/iron-containing sludge agglomerate, and coke are charged from a furnace top and air is blasted from a main tuyere and an upper tuyere, air is blasted from the main tuyere and the upper tuyere, so that the position L/H of the upper tuyere, the blast volume ratio V/(V+V) at the upper tuyere, and the flow velocity Vat the furnace center position of the blast at the upper tuyere satisfy any one of the conditions (1): L/H=0.25 to 0.80, V/(V+Vu)=0.21 to 0.37, V=10 to 25, (2): L/H=0.35 to 0.70, V/(V+V)=0.15 to 0.43, V=10-25, and (3): L/H=0.35-0.70, V/(V+V)=0.21 to 0.37, V=8 to 25, where L: the distance in the furnace height direction from the main tuyere to the upper tuyere, H: the distance in the furnace height direction from the main tuyere to the stock line, V: blast volume at the main tuyere, V: blast volume at the upper tuyere. |
