Siemens VAI Metals Technologies offers steelworks operators an electric arc furnace that has been specially developed for the use of direct reduced iron.

The Simetal EAF FAST DRI is designed for a continuous melting process as electrical energy input and DRI are supplied during tapping. This shortens tap to tap times and reduces specific energy consumption. An overall productivity increase of around 15% can be achieved with a 150 tonne furnace.

The arc furnace has a modular structure, which also makes it possible to retrofit existing, conventional furnaces. With this new furnace concept Siemens underlines its technological leadership in electric steelmaking.

The Simetal EAF FAST DRI electric arc furnace has a tiltable lower vessel with an extensive liquid heel. The resulting continuous flat bath operation allows electrical energy input and DRI feeding during tapping. Thanks to the patented furnace advanced slag free tapping system, charging, tapping and tap hole refilling are possible under power on conditions. Compared with conventional arc furnaces, tap to tap times can be reduced by up to 15%. Energy consumption is cut by 20 kilowatt hours per ton and electrode consumption falls by 10%. The continuous supply of electrical energy during flat bath operation not only improves productivity, but also avoids line harmonic distortions such as flicker.

The continuous operation of the furnace offers a number of other benefits. Coal and oxygen injection as well as foaming slag control can be implemented even more precisely. Slag free tapping results in an enhanced alloys yield and better steel desulphurization. Installation of additional burners thus becomes superfluous. Thermal stress on the refractory and structure materials also remains constant, prolonging their useful lives.

The Simetal EAF FAST DRI is designed so that, in combination with the Hot Transport System from Siemens, it can also be fed with hot DRI at temperatures of around 600 °C. Thanks to the modular design of the new electric arc furnace, existing furnace installations can also be retrofitted with FAST DRI technology.