FERRONIOBIUM ALLOY FINES AGGLOMERATION THROUGH BRIQUETTING
André Carlos Silva, Mariana Rezende de Barros, Kléber Silva Macedo, Elenice Maria Schons Silva
Abstract
Brazil is the largest producer of Niobium alloys, with a production of 58,000 tons of Nb2 O5 concentrate in 2016, corresponding to a 92.81% of the world production. The Brazilian Niobium ores grades vary from 0.51 to 2.71%. Ferroniobium (Fe-Nb) is an iron niobium alloy with niobium content of 60-70%. It is the main source for niobium alloying of HSLA steel and covers more than 80% of the worldwide niobium production. In 2014, Brazil produced 51,737 tons of Fe-Nb, being around 90% of it for exportation. In the final stage of the Fe-Nb production, the alloy needs to be crushed in a jaw crusher, which generate fine particles (around 26% of the feed below 10 mm at Niobras/CMOC). The selling price of the fine particles have a significant loss in the market, since the fine particles cannot be used directly in steelmaking. A process to agglomerate the Fe-Nb fine particles into briquettes with size and chemical composition similar to original products was developed. Organic binders were used as well as a lubricant agent. The briquettes were characterized both physically and chemically. For the physical characterization, the briquettes were tested for mechanical and water resistance, thermal shock and Brinell hardness. Briquettes containing addition of 3% of zinc stearate, 2% of iron powder, and 1% of water reached a Niobium content above 62% and contaminants levels of below the standard Fe-Nb specifications. The results indicate that Fe-Nb alloy fines can be technically and economically agglomerate by briquetting.
Keywords
Referências
1 Mendes MWD. Obtaining Nb powders from the thermal aluminum reduction with plasma ignition [dissertação]. Natal: Universidade Federal do Rio Grande do Norte; 2005.
2 Sousa RMF, Fernandes LE, Guerra W. Niobium. Química Nova na Escola. 2013;35:68-69.
3 Damasceno EC. Availability, supply and demand of ores for metallurgy. Rio de Janeiro: CETEM/MCT; 2006. Série Estudos e Documentos - CETEM/MCT.
4 USGS Science for a Changing World. Niobium (columbium) and tantalum statistics and information. USA: USGS; 2017 [cited 2017 Aug 3]. Available at: https://minerals.usgs.gov/minerals/pubs/commodity/niobium/
5 Companhia Brasileira de Metalurgia e Mineração. Situação de exploração e exportação de nióbio. Araxá: CBMM; 2017 [cited 2017 Aug 3]. Available at: https://www2.camara.leg.br/atividade-legislativa/comissoes/comissoespermanentes/cme/audiencias-publicas/2017/30-08-2017-situacao-de-exploracao-e-exportacao-de-niobio/CBMM_30_08.pdf
6 Carvalho EA, Brinck V. Aglomeração: Parte I: briquetagem. In: Luz AB, Sampaio JA, França SCA. Tratamento de minérios. 5. ed. Rio de Janeiro: CETEM/MCT; 2010.
7 Moraes SL, Kawatra SK. Evaluation of the use of combinations of binders in the pelletization of magnetite concentrate by balling drum technology. Tecnologica em Metalurgia, Materiais e Mineração. 2011;8(3):168-173.
8 Telles VB, Espinosa DCR, Tenório JAS. Iron ore sinter production using electric arc furnace dust as raw material. Tecnologica em Metalurgia, Materiais e Mineração. 2013;10(1):72-77.
9 Lucena DA, Medeiros RD, Fonseca UT, Assis PS. Fine charcoal agglomeration and its feasibility for blast furnace usage and for energy generation. Tecnologia em Metalurgia e Materiais. 2008;4(4):1-6.
10 Silva AC, Silva EMS, Barros MR, Marinho DY. Limestone fines reuse for agriculture through briquetting. Tecnologica em Metalurgia, Materiais e Mineração. 2016;13(4):365-372.
11 Associação Brasileira de Normas Técnicas. NBR 12767/92 - Rochas para revestimento - Determinação da resistência à compressão uniaxial. Rio de Janeiro: ABNT; 1992.
12 Falcão MFB, Soares JB. Considerations on the diametrical compression test in the study of paving materials. In Anais do XVI Congresso de Pesquisa e Ensino em Transportes; 2002; Natal, RN, Brasil. Natal: ANPET; 2002.
13 Cunha AF, Mol MPG, Martins ME, Assis PS. Characterization, improvement and recycling of careloads generated in steel processes. REM Revista Escola de Minas. 2006;59(1):111-116.
14 Callister WD, Rethwisch DG. Materials science and engineering: an introduction. 9th ed. USA: John Wiley & Sons; 2013.
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