A theoretical study of the effect of ladle-slag additions on the BOF process
(English)Manuscript (preprint) (Other academic)
A Case study has been performed using the commercial Multi‐Phase equilibrium (MPE) software. The aim was to study the effect on the energy balance of an industrial BOF converter when recycling of ladle slag is made to the process. A reference simulation was made with typical process parameters of an industrial converter without the addition of ladle slag. The energy penalty of recycling ladle slag to the process was found to be 1728 MJ. Moreover, five different options to obtain an energy balance in the converter were studied. The results showed that either the scrap weight could be decreased by 1.5t, or the iron‐ore addition could be reduced with 380 kg. These two solutions offered consistent metallurgical performance in the process, but had drawbacks due to a decreased yield and an increased blowing time respectively. It was also found that the chemical energy released from the process could be increased, by oxidizing FeO or adding FeSi. However, this had negative effects on the process time as well as the steel quality. The most beneficial way for the BOF process to compensate for the energy loss is to reduce the tapping temperature with 12°C. This will also have positive effects on the phosphorus removal in the process. The results also showed that 200 kg per heat of burnt lime could be saved thanks to the recirculation of ladle slag. However, concluding remarks on the environmental and economical effect of the different options to compensate for the energy penalty needs to be assessed by a Life Cycle Analysis in the future to which this study can act as a useful guide.
Energy balance, simulation, ladle slag, recycling, BOF
Metallurgy and Metallic Materials
IdentifiersURN: urn:nbn:se:kth:diva-33300OAI: oai:DiVA.org:kth-33300DiVA: diva2:414319
QS 20112011-05-032011-05-032011-05-03Bibliographically approved