| 摘要 |
PURPOSE:To stabilize the formation of mushroom and to prolong the life of nozzles in a top and bottom-blown converter refining by using a concentrated nozzle formed to have a specified sectional area of the pipe and degree of concentration to perform bottom-blow of the stirring gas with a specified flow rate. CONSTITUTION:A single nozzle 1 having 0.24-1.4% degree of concentration of metallic pipes 3 having <=30mm.<2> sectional area is formed. This concentrated nozzle 4 is fitted to a brick wall 6 at the bottom of a converter, and CO2 or a gaseous mixture produced by mixing about 5-30% O2 with CO2 is blown into the converter after adjusting the flow rate to 1,000Nm<3>/hr nozzle. By this refining process, a normally grown mushroom covering the whole surface of the bottom blowing nozzle 4 is formed, and the damage of the bottom-blowing nozzle 4 by the molten iron is prevented. Damage of the nozzle due to spalling is also reduced remarkably, thus, the life of the bottom blowing nozzle 4 is improved. |
