| 摘要 |
<p>PURPOSE:To improve the productivity and the thermal efficiency in a cylindrical furnace for producing molten iron and to prolong the service life of refractory. CONSTITUTION:In this cylindrical furnace 1, primary tuyeres 5 at the lower side wall, secondary tuyeres 6 at the upper side wall and a bosh part 3 whole diameter gradually increases upward at the further upper part are arranged. The lower part from the secondary tuyeres may have the structure whose diameter enlarges downward. After forming coke packing layer at the lower part of the furnace below the secondary tuyeres and iron scrap and iron ore packing layer at the upper part thereof, assist gas and oxygen-containing gas are supplied from these tuyeres to produce a pig iron. CO gas generated at the front of the primary tuyeres 5 is risen to the furnace wall side of the coke packing layer at high flowing velocity and burnt at the front of the secondary tuyeres 6 and the high velocity CO2 gas generated at the furnace wall side is lowered is velocity at the bosh part 3. By this method, the flowing velocity of the CO2 gas in the radial direction in the iron scrap and iron ore packing layer is uniformized and the heating and melting is uniformly progressed, and also, the erosion caused by overheat of the side wall refractory is prevented.</p> |
