| 摘要 |
PURPOSE:To perform preliminary refining such as desiliconizing, dephosphorizing and desulfurizing of molten iron separately and efficiently by constituting a vessel for preliminary treatment of the molten iron into a horizontal cylindrical shape which is divided to plural chambers by means of partition walls having communicating ports. CONSTITUTION:Prior to refining of molten iron to steel by decarburizing in a converter, the molten iron is subjected to preliminary refining such as desiliconizing, dephosphorizing and desulfurizing. To this end the molten iron is put into the chamber A of a vessel 1 of a horizontal cylindrica or polygonal shape which is divided to both chambers A and B by means of a partition wall 16 having an opening 17, through an iron receiving port 5. Iron oxide powder, etc. are blown into the molten iron by means of a carrier gas with a lance 8 through the port 5 to desiliconize the molten iron. The vessel 1 is turned around the shaft to transfer the desiliconized iron 18 into the chamber B through the opening 17 povided near the cylindrical wall of the partition wall until the melt surfaces of the molten iron in both chambers A, B are made flush. A flux for dephosphorizing, etc. are blown with a lance 9 in the chamber B to dephosphorize the molten iron. Likewise, the molten iron is desulfurized in the next chamber. Since the respective preliminary refining treatments are accomplished separately in the same vessel, the efficiency of preliminary refining is improved. |
