EAF dust: An overview on the influences of physical, chemical and mineral features in its recycling and waste incorporation routes

Electric-arc furnace dust (EAFD) is one of the several process residues generated in mini mills during steel production. The presence of valuable zinc in EAF dust and the rising costs for waste disposal are the motivating factors for EAFD recycling or its incorporation into other materials. Features such as small particle size, high zinc content and the existence of the decomposition-resistant mineral franklinite have long influenced both positively and negatively EAF dust processing. More recently, the growing presence of deleterious chlorine, lead and chromium is affecting equally the traditional as well as the new recycling routes or waste incorporation processes in a decisive way. In this study, a critical overview on the fundamentals of pyrometallurgical and hydrometallurgical EAF dust recycling or incorporation processes is presented, as a starting point for the understanding of how the EAF dust processing routes are influenced by all cited factors. Especially important is the discussion on the influences of the dust composition - including the effects of the deleterious elements - which can point out some relevant issues that ought to be considered for a successful ending to old and new dust processing proposals.