Development of Refining Process for Production of High Purity Ultra-low-carbon Steel

Reaction Model for Carbon, Manganese, and Oxygen in Bottom Blowing with Mixed Gas in Final Stage of Steel Refining in Converter

“…The blowing sequence in the final stage of refining in the converter has been improved by adopting various measures suggested by these three items. For example, in the bottom blown converter, the oxygen gas flow rate is decreased 1) (item c)), whereas in the top and bottom blown converter, the inert gas flow rate is increased 2,3) (item a)), inert gas is added to the oxygen gas 3) (items a), b)), or the bottom blowing gas is changed from oxygen to inert gas 4) (items a),b)). On the other hand, several indexes such as ISCO, 5) BOC, 6) I, 7) and ICO 8) have been proposed to explain the metallurgical reactions in the final stage of refining and were used to compare various oxidizing refining furnaces and design the respective blowing sequences.…”