| 摘要 |
PURPOSE:To supply sufficient heat to a steel bath, to prevent waste of oxygen, and to recover the waste gas with high efficiency by stopping the supply of gaseous oxygen for the secondary combustion at the initial and the terminal stage of blown refining in secondary-combustion system converter refining. CONSTITUTION:Gaseous oxygen is introduced through a gaseous oxygen supply nozzle for the secondary combustion, and the gaseous CO generated in the furnace during blown refining is secondarily burnt. In said converter refining, supply of gaseous oxygen for the secondary combustion is stopped at the initial stage of refining wherein a desiliconization reaction proceeds and at the terminal stage wherein a low-carbon region is formed. In addition, while the gas supply is stopped, an inert gas such as argon or a gas having low partial pressure of oxygen such as steam and air is injected instead from the gaseous oxygen supply nozzle for the secondary combustion to prevent the clogging in the nozzle. By said refining method, sufficient heat can be supplied to the steel bath in the furnace, and the yield of Mn and the yield of charge of a cooling agent can be enhanced. |
