Studies on dust recycling in the electric arc furnace at Uddeholm Tooling AB

• Published in: Scandinavian Journal of Metallurgy
• Main Authors: Yang, Qixing, Gustafsson, Börje
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2003
• Subjects: Luleå
• Online Access: http://dx.doi.org/10.1034/j.1600-0692.2003.00637.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1034%2Fj.1600-0692.2003.00637.x; https://onlinelibrary.wiley.com/doi/pdf/10.1034/j.1600-0692.2003.00637.x; https://onlinelibrary.wiley.com/doi/full-xml/10.1034/j.1600-0692.2003.00637.x

The electric arc furnace (EAF) generates dust containing about 21% Zn during primary steelmaking at Uddeholm Tooling AB. Research work on upgrading of the dust has been carried out jointly by Uddeholm Tooling AB and MiMeR, Minerals and Metals Recycling Research Centre, at Luleå University of Technology. The work included laboratory studies and plant trials. The laboratory studies, with 6 dust smelting tests at temperatures around 1650°C, demonstrated that the smelting had no negative effects on qualities of the steel and slag. It was also shown that both carbon and silicon could be used to reduce the oxides in the dust, leading to high metal recoveries. Based on the study results, plant trials were performed at Uddeholm Tooling AB. The trials consisted of 100 EAF heats, recycling dust at a rate of 925 kg/heat. No negative impact has been found on the furnace products and production. The Zn content of the obtained dust increased by 11% and the weight of the generated dust decreased by 42%. The material costs for the dust recycling during the trials were rather low, $0.4 (4–5 SEK)/tonne steel. Some of the test results are interpreted by virtue of mass and energy balances of the dust smelting calculated using the computer software “Chemsage.” By utilizing results from the tests and calculations, the energy consumption for dust smelting was estimated.