Influence of the Kinds in Injection Gases on the Dephosphorization of Hot Metal

Abstract

Recently, it is clarified that dephosphorization of hot metal by lime injection with oxygen is more effective than usual dephosphorization with nitrogen. Then the authors made dephosphorization tests by lime injection to compare two kinds of injection gas (N₂ and O₂), and discussed the dephosphorization reaction on each condition.
As a result, following items were clarified. The rate of dephosphorization by lime injection is mainly dependent on oxygen feeding rate and slagging rate of lime. So the rate of dephosphorization by O₂ injection is larger than that by N₂ injection.
Therefore, it is desirable to adopt a lime injection with O₂ gas to increase the reaction rate and to decrease the consumption of lime.
Then, it becomes a subject of discussion that decarburization is accelerated by O₂ injection. However, it is possible by use of mixed gas of N₂ and O₂ to control the decarbuization rate and dephosphorization rate to a certain extent.