The Production of Steels Applying 100 DRI for Nitrogen Removal, The Experience of ArcelorMittal Lazaro Cardenas Flat Carbon

摘要

ArcelorMittal Lazaro Cardenas Flat Carbon has been the steelmaking shop pioneer in the World producing the most of its steel grades applying 100% DRI. This technology allows the steel production with low Nitrogen content (30-35 ppm for LCA1K and 35-45 ppm for API X steel grades). It has been established that the main methods for Nitrogen removal are: Carbon Oxidation and the Usage of high proportions of DRI. The usage of 100% DRI promotes since the beginning of the heat a very important CO evolution that protects the metal bath from the air filtration. The high Carbon contained in the DRI is one of the key of success because promote a vigorous foaming slag formation through all the heat. The variation in the%C in the DRI and its effect in the final Nitrogen in the steel will be discussed in this presentation. A mathematical model for phosphorus reaction and nitrogen evolution is applied in order to explain the results.