Study on metallurgical characteristics of the bottom-blown O₂–CaO converter

Abstract

In this paper, the industrial experiment of bottom-blowing O 2 -CaO was carried out by using a mixed injection of multi-gas medium to reduce the erosion of bottom-blown components and improve the life of the converter. The mechanism of slagging and dephosphorization during the process of bottom-blowing O 2 -CaO was deeply studied, a better way of slag making by blowing CaO powder from the bottom of the converter was described in detail, and the corresponding model of slag-forming was established. The research illustrates that the dephosphorization reaction in the bottom-blown O 2 -CaO process is a 'transient reaction', and a comprehensive model of dephosphorization process was established. On the basis of experimental data, it is found that [%C]•(%FeO) and [%C]•[%O] are linearly related to [%C] respectively, meanwhile, their relationship equations were obtained by the fitting method and shown in the paper.

Analysis of Carbon Dioxide Emissions in Bottom-blowing O2-CO2-CaO Process in Basic Oxygen Furnace Steelmaking

“…Addressing this gap, we have pioneered a lime powder spraying technique at the base of a converter during steelmaking, a method that underwent rigorous industrial testing and found practical application in the dephosphorisation converter of a steel plant's duplex converter. 12,13 This innovative approach involves introducing lime powder into the molten bath of the converter, carried by a blend of O 2 and CO 2 as the carrier gases, from the converter's base. This method ensures continuous and controllable feeding, facilitating more precise regulation of reactions within the molten steel, and enhancing the utilisation efficiency of oxygen and lime.…”

“…Addressing this gap, we have pioneered a lime powder spraying technique at the base of a converter during steelmaking, a method that underwent rigorous industrial testing and found practical application in the dephosphorisation converter of a steel plant's duplex converter. 12,13…”

High‐Efficiency Dephosphorization by Bottom‐Blown O2‐CaO Process for Semi‐Steelmaking

“…In the bottom‐blown O 2 ‐CaO process, the reactions between the O 2 and steel elements release a lot of heat, which produces a high‐temperature fire‐spot zone. [ 15–17 ] Furthermore, in our previous study, we found that CaO powder melting required a lower temperature of the molten bath by analyzing the effect of molten bath temperature on theoretical limitations of the dephosphorization reaction, CaO powder melting, and slag fluidity. In turn, we determined that the fire‐spot zone of the bottom‐blown O 2 ‐CaO process promotes CaO powder melting.…”