Danieli to supply technology to Nucor Arizona mill

Nucor Corp., a Charlotte, North Carolina-based electric arc furnace (EAF) steelmaker, has selected technology from Italy-based Danieli & C. S.p.A. to help it set up a “digital melt shop” at its expanding facility in Kingman, Arizona.

Danieli Digimelter and Digirefiner units will be installed in place of a prior shaft-type direct current (DC) furnace. The Italian firm says its technology has been designed “to competitively produce liquid steel in excess of 630,000 short tons per year.” The melt shop will feed a nearby caster and an existing Danieli bar mill.

Both Digimelter and Digirefiner will be powered by a Q-One power feeder that makes use of semiconductor devices, according to Danieli. Q-One has been designed to overcome “limitations of traditional power feeding systems and yields, ensuring unparalleled advantages to both power feeding and the furnace melting process,” Danieli says.

The technology can lead to “the practical elimination of network disturbances and greater efficiency of the furnace operation,” adds the firm. Hybrid by design, Q-One also allows for use of renewable energy sources generated at the site. Management of the overall melting process will be performed by what Danieli calls its Q-Melt suite of products.

“This is the fully dynamic, Danieli adaptive process control of the EAF working parameters for both electrical and chemical profiles, and allows for the reduction of the process variability with notable benefits in terms of furnace utilization factor and efficiency,” Danieli says.

The technology provider says Nucor Steel Kingman will become “the most technologically advanced digital melt shop thanks a complete suite of technology packages and robotics, according to zero-men-on-the-floor concept.”

Q-ATS is an automatic tapping system, including Q-Slag, Q-Sand and Q-EBT eye for slag detection, eccentric bottom tap-hole (EBT) sand refilling and remote monitoring. Q-Stap and Q-Strop execute remote controlled opening and cleaning of the tap hole. Q-SmartEC provides auto-adaptive electrode cooling. Thor 3K performs slag door automatic cleaning and sealing while Q-SLC controls the steel level in the furnace.

The contract includes a “dedicated raw material handling system for additions at EAF tapping and at the ladle furnace, new downcomer and settling chamber for the primary fumes, and a 30-ton scrap yard crane.”

The Nucor Steel Kingman digital melt shop is expected to be fully operational by the third quarter of 2024, according to Danieli.