South Korean special steel producer SeAH Besteel has contracted Danieli to increase the process efficiency for EAF 3 at the Gunsan meltshop. The steel quality targets indicated for this 100-ton electric furnace require the use of low-residual scrap, which results in very dense charge mixes. The need to avoid over-oxidation, thus to maximize process repeatability and steel quality, together with the target of maximizing arc stability and active power in the presence of high-density scrap, were the major reasons for selecting the Q-MELT technological package.
The installed Q-MELT consists of Q-REG electrode control regulator
LINDARC real-time gas analysis, laser based, with closed-loop control of soft-blown oxygen during scrap melting
MELTMODEL for dynamic adaptation of oxygen flowrate setpoints during refining, according to bath oxidation levels
The results can be summarized as a 2% increase in average active power, a 2% reduction of electrical energy consumption, and a 15% standard-deviation decrease of oxygen content in the steel before tapping.