| 摘要 |
<p>PROBLEM TO BE SOLVED: To apply dephosphorizing treatment at a high reaction efficiency while restraining a rephosphorization, in the case of reusing decarburized slag in the dephosphorizing treatment of molten iron by using a refining furnace having a top and bottom combining-blowing function. SOLUTION: In the dephosphorizing treatment for molten iron with the refining furnace having the top and bottom combining-blowing function by using recycle slag containing >=1% phosphoric acid, the method for recycling the slag containing the phosphoric acid is performed, with which the top-blown oxygen feeding speed is regulated to be 0.8-2.4 Nm3/min/t, mass ratio (P2O5/CaO) of P2O5 and CaO in the slag after dephosphorizing is regulated to <=0.15 and CaO/SiO2 is regulated to 1.2-2.2.</p> |
