| 摘要 |
<p>PURPOSE:To produce low nitrogen molten iron at good thermal efficiency by forming coke packing layer and scrap and iron ore packing layer thereon in a furnace bottom and blowing combustion supporting gas having the specific nitrogen content and tuyere cooling gas from primary and secondary tuyeres. CONSTITUTION:In a cylindrical furnace 1, opening part 2 for discharging furnace gas and charging raw material at the upper part, molten iron tapping hole 5 at the furnace bottom part, slag discharging hole 6 and the primary tuyeres 3 at lower part of furnace wall and be secondary tuyeres 4 at the upper part, are arranged. By using this cylindrical furnace 1, the low nitrogen molten iron is produced. Then, the coke packing layer 7 from the furnace bottom to the level containing the primary tuyeres 3 is formed, and the scrap and iron ore packing layer 8 thereon is formed. Further, the combustion supporting gas having <=40vol.% nitrogen content and the tuyere cooling gas are blown from the primary and secondary tuyeres 3, 4. By this method, the production cost for the low nitrogen molten iron can be reduced.</p> |
