| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a technique for dephosphorizing hot metal using a converter, capable of stably achieving the dephosphorizing rate of 80% or more in the treatment time of 5 to 8 min without substantially using halogenated material such as fluorite and also without generating difficulty in operation due to spitting or slopping. <P>SOLUTION: The technique includes: blowing a top-blown oxygen to the hot metal housed in the converter at the flow rate of 1.5-2.5 Nm<SP POS="POST">3</SP>/min/ton; blowing together with the oxygen, the total mass of CaO supplied as a dephosphorizing agent in a powdery state; blowing a bottom-blown gas to the hot metal at the flow rate of 0.15-0.8 Nm<SP POS="POST">3</SP>/min/ton; and controlling a slag composition at the time when dephosphorization finishes to be 2.2-3.2 in basicity, Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>of 4.5-7.5 mass%, and T.Fe of 7-13 mass%. <P>COPYRIGHT: (C)2012,JPO&INPIT |
