Simulation and application of submerged CO2–O2 injection in EAF steelmaking: combined blowing equipment arrangement and industrial application

Abstract

Submerged CO2–O2 injection is a new method for electric arc furnace (EAF) steelmaking. And it’s necessary to optimize the arrangement of submerged nozzles and oven wall oxygen lances used in an EAF. In this study, the characteristics of metallurgical reaction in EAF metal bath during submerged injection and oven wall oxygen supply were analysed. The submerged nozzles’ agitation action was focused on the bath’s middle and lower part, while that of oven wall oxygen lances was focused on the upper part. The EAF combined blowing arrangement comprising two oven wall oxygen lances in Mode F and two submerged nozzles in Mode B contributes to the bath stirring significantly by forming a circulating flow. In the industrial experiments performed with submerged injection, the final phosphorus content, the endpoint carbon and oxygen equilibrium and the FeO content in molten slag were reduced by 5.28%, 0.00 066 and 0.0038%, respectively.