Dust formation in Electric Arc Furnace:: Birth of the particles

The characterization of Electric Arc Furnace (EAF) dust shows that bubble burst at the liquid steel surface is the principal source of dust emission. We have therefore developed an experimental device for studying this phenomenon. As in the case of the air-water system, the bubble-burst gives birth to two types of droplets: film drops and jet drops. The jet drop formation is observed with high-speed video. The film drop aerosol is collected on filters and then characterized by means of SEM, granulometric and gravimetric analyses. Results are presented and discussed. The quantification of both types of projections leads to the conclusion that the film drop projections represent the major source of dust. The amount of film drops greatly decreases with the parent bubble size. Under 4.5 nun in bubble diameter, no film drops are formed. Decreasing enough the bubble size would therefore represent an effective solution for reducing drastically the EAT dust emission. (c) 2005 Elsevier B.V. All rights reserved.