| 摘要 |
<p>PURPOSE: To make it possible to discharge slag lowered in basicity by subjecting molten iron to dephosphorizing and desulfurizing treatments in a vessel, and after delivering this molten iron, allowing the slag to remain therein, receiving the molten iron subjected to a hearth desiliconizing treatment into the above vessel, subjecting the molten iron to the dephosphorizing and desulfurizing treatments and discharging the slag. CONSTITUTION: The molten iron tapped from a blast furnace is subjected to the hearth desiliconizing treatment and is received into the vessel where the molten iron is subjected to the pretreatments of the dephosphorizing and desulfurizing treatments. This molten metal is delivered from the vessel. The vessel where the slag is held left is passed through a skimmer and, thereafter, the molten metal subjected to the hearth desiliconizing treatment is received thereto and is subjected in this state to in-vessel desiliconization. The slag is then discharged and the operation to subject the molten iron to the dephosphorizing and desulfurizing treatments is repeated. The slag of the molten iron pretreatments which is low in the basicity and small in expansion rate is thus obtd.</p> |
