| 摘要 |
<p>PURPOSE: To promote dephosphorizing (de-P) reaction by dropping remaining metal with an oxygen cutting into molten metal at the time of melting a large part of the metal beforehand charged in a basic arc furnace and forming oxygen-enriched condition in the furnace. CONSTITUTION: The metal 2 is blended so as to become the target component or lower at the time of perfectly melting the metal 2 beforehand charged in the basic arc furnace 1. The remaining metal 2 at the time of melting about 80% of the metal 2 is oxygen-cut by using a lance pipe 3 and dropped into the molten metal 4 to form the atmosphere in the furnace to the oxygen enriched condition. At the time of perfectly melting the dropped metal 2, the steel slag 6 in the furnace 1 is discharged and mixed powder of CaO, Al2 O3 and iron oxide in by wt. ratio of 1:1:1-8:2:1 as de-P agent is charged. At the time of perfectly melting the de-P agent, the tip part of the lance pipe 3 is dipped into the molten metal 4 at 1500-1550 deg.C, the gaseous oxygen 5 is blown to increase the oxygen activity in the molten metal 4, and after promoting the de-P reaction, the steel slag 6 is discharged from the furnace 1.</p> |
