EAFtechnologie

EAF technology refers to electric arc furnace steelmaking, a method in which electrical energy is used to melt metallic charge and produce steel. In an EAF, a refractory-lined vessel holds a charge that is predominantly ferrous scrap, which is melted by heat generated from an electric arc struck between graphite electrodes and the charge. Direct reduced iron (DRI) or pig iron can be added to adjust chemistry. The furnace can be operated with alternating current (AC) or direct current (DC). After melting, refining is performed through controlled oxidation, slag formation, and alloying to achieve the desired composition, followed by tapping to cast the steel.

Materials and process notes: The primary input is recycled scrap, supplemented by DRI or virgin iron as needed. Fluxes such as lime are added to form slag that captures impurities. The process emphasizes rapid heating, flexibility, and the ability to adjust chemistry in the refine stage. Electrode wear and transformer losses contribute to operating costs and energy consumption.

Advantages and context: EAFs generally offer lower capital investment and shorter installation times compared with blast furnace-based routes, and they can accommodate variability in scrap supply and batch sizes. When powered by low-carbon electricity, EAF steelmaking can have relatively low CO2 emissions per ton compared with other routes; however, emissions depend on the electricity grid and gas handling in the refining stage.

Applications and limitations: The technology is widely used for carbon and stainless steels, especially where recycling and flexibility are priorities. Limitations include reliance on scrap quality, energy price exposure, and electrode wear, which affect operating costs.