Investigation of metal/slag/gas reactions during tank degassing for the production of ultra low carbon and extra low carbon steels

Abstract

The objective of this work was to develop a practical secondary metallurgical treatment model for a production of ultra low carbon steel (ULC) and extra low carbon steel (ELC) via ladle heating furnace (LHF) and vacuum oxygen decarburization unit (VOD). In this investigation, the secondary steel treatment model for production of ultra low carbon and extra low carbon steels was developed using fundamentals of secondary metallurgy and thermal and mass balance calculations with suitable assumptions. The model was tested by comparing to the industrial productions in the steel plant of Dillinger Huette GTS, Germany. The desulfurization, denitrogenization and decarburization practice as well as the process temperature control for the production of the ELC and ULC steel grades were reliable and applicable to the process. Furthermore, all important information and operation were summarized and simplified to render their applications practical for actual EAF-LHF-VOD operation.