| 摘要 |
PURPOSE:To improve the secondary combustion efficiency near the side wall of a furnace and to uniformly foam slag by blowing an oxidizing gas for secondary combustion of the gas in the furnace through tuyeres provided on the side wall of the furnace into a slag layer and burning the gaseous CO floating on the slag layer. CONSTITUTION:Oxygen is supplied through the tuyeres 14, 15 into the bath B of a molten iron contg. >=2% carbon. Coal powder as well as preheated and preliminarily reduced ore and preheated and calcined lime powder are blown by utilizing the reducing gas generated in the melting furnace 10 through the tuyeres 14, 15 into the furnace to execute melt reduction. The generated gaseous CO is subjected to the secondary combustion by the oxidizing gas blown through tuyeres 17, 18 provided on the side wall 13 of the furnace to generate gaseous CO2. The gaseous CO2 is raised through the slag layer S to transfer the sensible heat thereof to the iron powder and slag particles. The secondary combustion of the gaseous CO generated in the central part of the slag layer is accelerated. The slag is formed in the uniform foaming state by the above-mentioned, by which the secondary combustion efficiency and heating efficiency are improved. |
