It is well known that electric arc furnace (EAF) steelmaking consumes large amounts of power. But what exactly causes high energy consumption? Let’s take a look.
① Raw material conditions
EAF steelmaking relies heavily on scrap steel. When lightweight scrap or compacted scrap is used, feeding becomes difficult, often causing material blockage and heat loss. If the initial charge is insufficient, a second or even third charge is needed, resulting in additional heat loss. Every extra charge (about 5 minutes) increases power consumption by 7–12 kWh per ton.
After melting, if excessive carbon (C) and phosphorus (P) are detected, the oxidation stage required to remove these elements takes longer and consumes more energy.
② Operator skill and process control
The melting stage accounts for 60%–70% of total power consumption. A common issue is blind slagging during phosphorus removal in the oxidation stage, which wastes energy and materials.
③ External operating conditions
During production, sudden power restrictions or outages may occur. Once power is cut, the molten steel cools and begins to solidify, requiring reheating and remelting—wasting a large amount of energy.
④ Unexpected operational incidents
Improper operation may cause electrode breakage. Handling a broken electrode results in significant heat loss.
If chemical composition fails during the reduction stage, a second oxidation process may be needed, increasing energy consumption.
Other issues such as burner water leakage or slag buildup requiring furnace opening will delay smelting time and increase heat loss.
These are the main reasons for high power consumption in EAF steelmaking, summarized by vacuum consumable electrode arc furnace manufacturers.