Replacement of Electric Arcs with Burners

Abstract

Analysis of attempts to develop steelmelting units operating with scrap without utilizing electric arcs. Reasons of failures.

Limited possibilities of low-power sidewall oxy-gas burners. The constant flame direction as a basic factor hindering the increase in burner power. High-power rotary (HPR) burners. Moving the flame of HPR-burners from those already heated to the relatively cold zones of scrap pile during the heat allows to increase their power up to 20–30 MW and the energy efficiency coefficient η up to 0.7.

HPR-burner design variants: roof, oriel (balcony), and sidewall. They open new possibilities for replacing electrical energy with fuel. Two-stage process of the heat: at the first stage the scrap is only heated by the burners, and at the second one the scrap is heated with both the burners and arcs or with the arcs only.

Results of trials of both HPR-burners and two-stage process in 6-ton, 100-ton, 200-ton furnaces prove the reality of developing a 120-ton fuel arc furnace (FAF) operating on scrap with basic performances as follows: tap-to-tap time − 35 min; consumptions are electrical energy − 140 kWh/ton; natural gas − 25 m³/ton; oxygen − 80 m³/ton. Maximal power of transformer − 85 MW, that of 5 HPR-burners − 137 MW.