Tecnologia em Metalurgia, Materiais e Mineração
https://tecnologiammm.com.br/article/doi/10.4322/2176-1523.20222323
Tecnologia em Metalurgia, Materiais e Mineração
Original Article

Self-reducing pellets composed of wastes from steelmaking production for their recycling

Felipe Buboltz Ferreira, Ana Rosa Rabelo de Lima, Eduardo Osório, Antônio Cezar Faria Vilela, Rüdiger Deike

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Abstract

This paper presents a study about the recycling of a mixture of EAF filter dust and mill scale; and slag, in the form of self-reducing pellets. At first, chemical and morphological characteristics of the material were investigated. Pelletizing was carried out manually, with the use of graphite 100% fixed carbon and molasses as binder with moisture. The results of reduction tests under the temperature of 1200 ºC for the wastes could be analyzed according to the use of different contents of reducing agent, time and mass loss. It was found that 20% of the carbonaceous material was the best configuration for a maximum mass loss, for both wastes. Furthermore, the pellets composed of stainless steel slag, added to the metallic bath presented a chromium recovery of around 95%, indicating its potential reuse.
 

Keywords

Steelmaking wastes; Pellets; Self-reduction; Recycling

Referências

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Submetido em:
01/04/2020

Aceito em:
12/04/2021

6215507fa953952cb80d3322 tmm Articles
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