Sähkökaariuunien

Sähkökaariuuni, often translated as electric arc furnace (EAF), is a type of metallurgical furnace that uses electric arcs to melt and refine metals. These furnaces are predominantly employed in the steel industry for recycling scrap steel and producing steel from direct reduced iron (DRI). The process involves passing a high-voltage electric current through electrodes, typically made of graphite, that are suspended above the metal charge. This creates an electric arc between the electrodes and the charge, generating intense heat that can reach temperatures exceeding 3000 degrees Celsius.

The primary advantage of electric arc furnaces is their flexibility. They can efficiently melt a wide variety of ferrous scrap, making them a key component of the circular economy in steel production. EAFs also offer precise temperature control, which is crucial for producing high-quality steels with specific alloy compositions. The melting process is relatively fast compared to other furnace types. Modern EAFs incorporate advanced technologies for energy efficiency and emission control.

The basic components of an electric arc furnace include a refractory-lined shell, a movable roof, electrodes, a tilting mechanism for tapping molten metal, and a power supply system. The electrodes are gradually lowered as the metal melts, maintaining the arc. Oxygen is often injected to help with melting and refining. After melting, alloying elements can be added, and further refining may occur to remove impurities. The molten metal is then tapped into ladles for subsequent processing, such as continuous casting. Electric arc furnaces are a vital technology in modern metal production, particularly for sustainable steelmaking.