EAF and secondary dust characterisation

Abstract

The basic knowledge of the physical and chemical properties of the electric arc furnace (EAF) and secondary dust (SD) obtained by the characterisation provides important information on the potential problems that could be encountered during the processing of such materials. EAF dust consists mainly of very fine spherical particles. The most common phases in the EAF dust are solid solution of iron spinels generally enclosed into a matrix of calcium-iron silicate glass. Leaching tests show that as the Zn/Fe ratio increases, there is an increase in the zinc extraction, whereas the iron extraction decreases as the Zn/Fe ratio increases. It was possible to produce a SD containing 55 . 8% zinc by means of charging EAF primary dust-coal composite pellets into an induction furnace. SD consists of very fine particles presenting a mean particle size of 0 . 26 mm. In addition, SD contains significant levels of iron, chloride and fluoride. The iron content in the SD was identified as being iron droplets ejected from the bath caused by high intensity gas generation during the smelting of the EAF primary dust-coal composite pellets.

Steel dust catalysis for Fenton-like oxidation of polychlorinated dibenzo-p-dioxins

“…1. These micrographs showed the various grain sizes, from 100 nm to 5 m, and highly agglomerated bunches of clusters, which were similar to other results as well as to the laser-type granule analysis results of 9.2 ± 6.2 m in median and 3.3 ± 1.1 m in average under the 5% consistent level [20,23,24,27]. The detailed image of the steel dust particles shows that spherical and quadrilateral shaped iron crystals form aggregated clusters.…”

“…However, the contents of toxic metals in dust vary owing to the raw materials and parts of the processes [19,23,24]. Reported data showed great differences among the studied countries and sampling locations [20,[23][24][25][26][27][28][29]. Nevertheless, isolating the pure steel dust in steel making processes could provide an inexpensive and convenient mineral source for Fenton-type treatments.…”

Modificação e caracterização do resíduo pó de aciaria elétrica (PAE) para aplicação em reações de redução de cromo (VI)

“…O formato esférico do PAE também foi observado em outros trabalhos da literatura e está relacionado ao mecanismo de sua formação, que ocorre pela ejeção de partículas do metal líquido e escória. 36,40 Na micrografia do PAE800H (Figura 3B) pode-se notar um aglomerado de partículas onde se distingue pontos de coloração mais clara, o que não foi observado para o PAE. Na microscopia do PAE800C (Figura 3C) nota-se claramente a presença de partícula de carvão, onde pode--se observar a presença de poros em sua superfície.…”

Use of EAF dust as heterogeneous catalyst in Fenton oxidation of PCP contaminated wastewaters

“…The increasing dust dumping costs and liabilities constitute a driving force for the adoption of new treatments and disposal methods. Hydrometallurgical, pyrometallurgical or hybrid processes can be used for the recovery of valuable metals [20,21], however, stabilization followed by landfilling is currently the common practice [22,23].…”