| 摘要 |
PURPOSE:To perform dephosphorization and desulfurization treatments simultaneously and to recover gaseous CO without combustion by specifying a solid- gas ratio at the stage of blowing carbonated dephosphorizing and desulfurizing agents into desiliconized molten iron by means of a carrier gas. CONSTITUTION:Carbonated materials, that is, CaCO3, Na2CO3 are blown as dephosphorizing and desulfurizing agents together with a flux into molten iron of <=0.20% content of Si. An inert gas is used as a carrier gas for blowing means, wherein a solid-gas ratio (powder to be blown kg/min/carier gas kg/min) is set at >=10.0. CO2, O2 are used other than N2 and Ar as the carrier gas. Here, if the solid-gas ratio is below 10.0, particularly abrupt production of gaseous CO occurs and the stable operation is infeasible. In this way, the waste gas of high content of the gaseous CO produced during the simultaneous dephosphorization and desulfurization is recovered positively with a recovering device provided in the upper part of a treatment vessel without allowing to contact with air. |
