Effect of oxyfuel burner ratio changes on energy efficiency in electric arc furnace at Co-Steel Lasco

Trials were conducted on Co-Steel Lasco's electric arc furnace (EAF) to eva luate the effect of oxyfuel burner ratio changes on furnace energy efficien cy and productivity. Carefully controlled trials with the collection of num erous process and sample data over 331 heats provided statistically signifi cant results. The oxygen available for post-combustion in the furnace was i ncreased by 19%. As the burners were operating at their maximum oxygen cons traint, this was achieved by decreasing the natural gas consumption by 43%. Results of this study indicate that decreases in terms of specific electri cal energy consumption (4.0%), power on time (5.0%), and tap to tap time (4 .5%) were realised. Slag chemistry, electrode consumption, and yield were n ot affected. Measurement data support the finding that more heat was transf erred into the steel with the post-combustion burners: a flat bath was achi eved earlier; high bath temperatures were reached more quickly; power on ti me was reduced, leading to reduced electrical energy consumption. Analysis suggests that furnace thermal energy losses were reduced by less air inleak age, less incomplete methane combustion, and earlier achievement of foamy s lag conditions.