ORAL
| SESSION: IronTueAM-R10 | 5th Intl. Symp. on Advanced Sustainable Iron and Steel Making |
| Tue Oct, 24 2017 | Room: Maria Mercedes & Maria Beatriz |
| Session Chairs: Jose Carlos D Abreu; Paulo Von Kruger; Session Monitor: TBA |
12:00: [IronTueAM03]
Cleaning Process of the Coarse Steel Maker Sludge with Recovery of the Metallic Content and Consequent Carbon Sequestration Erivelto
Souza1 ; Fernando Gabriel Silva
Araujo
2 ; Cristovam Paes
Oliveira
3 ; Jose Emanuel
Lopes Gomes
3 ;
1Universidade Federal de Sao Joao Del-Rei, Ouro Branco, Brazil;
2UNIVERSIDADE FEDERAL DE OURO PRETO, Ouro Preto, Brazil;
3Fundacao Gorceix, Ouro Preto, Brazil;
Paper Id: 200
[Abstract] This work describes a process of steel waste treatment— primarily steelmaking— of thick sludge, through a technique of ultrasonic bombing aiming to recover the metal content of this waste. During the manufacturing process of steel in LD converters, the liquid iron designed in oxidizing atmosphere converter, solidifies in the form of small spheres with a wide range of sizes. However, not all the spheres are perfect, because some will ultimately not be able to complete spheres formation due to variations in size, cooling speed, and surface tensions. The smaller the size of the spherical particles, the greater the degree of oxidation, which forms a dust that generates a "cement" ligand upon contact with water, and aggregates the other spheres with non-metallic particles involved in the production of steel (slag; Coke; Cao; etc.). This "dust" fills even some of the cavities’ hollow spheres. After washing of gases, the "sludge" formed will contain steel bead, which will then be bonded with each other and with impurities through the aggregate action of fine particles, here called "dust". The technique in question consists of the application of ultrasonic waves on a pulp, formed by the addition of water to the thick sludge. This ultrasonic bombing promotes dispersion of micro-particles of sludge binders and, consequently, of larger particles, causing individualization and cleaning of the interior of the hollow particles. After the break, the particles that make up the pulp will be completely released. The pulp is then forwarded to a gravity concentration step for recovery of spherical particles of high metal content (90 to 96% Fe). Each ton of recovered metallic material is used as scrap in steel fabrication while avoiding the consumption of 1.4 t of ore, 1.5 t of CO2 generated, and 440 kg of Coke consumption, to the same productivity of steel.
