Increased Productivity of API-X Steel Grades at ArcelorMittal Steel Lazaro Cardenas By Reducing Sources of Hydrogen During Melting and Refining in DRI Fed EAFs

摘要

The focus of this work is on minimizing sources of hydrogen from all suspected inputs in an effort to decrease process time in these degassing units. To this end, we have realized the importance of both the quantity and quality of the carry-over slag during tapping the EAF as having an impact on the ppm of hydrogen in the final product. In this paper, we show that slowing tapping speed results in less carry-over slag and in a measurable reduction in ppm H. This is corroborated by a slag detection system giving a visual of the tapping stream that easily identifies the portion of the tapping stream that is slag versus molten metal. This tool better enables operators to limit the amount of carry-over slag entrained into the dump ladle. In addition, key factors affecting the slag entrainment during Eccentric Bottom Tapping (EBT), such as hot heel size, and slag viscosity and slag volume, are also discussed.