Caracterização e comparação na flotação de minérios sulfetados chumbo-zinco com reaproveitamento do rejeito como pó de calcário agrícola
Ano de defesa: | 2022 |
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Autor(a) principal: | |
Orientador(a): | |
Banca de defesa: | |
Tipo de documento: | Dissertação |
Tipo de acesso: | Acesso aberto |
Idioma: | por |
Instituição de defesa: |
Universidade Federal de Minas Gerais
Brasil ENG - DEPARTAMENTO DE ENGENHARIA MINAS Programa de Pós-Graduação em Engenharia Metalúrgica, Materiais e de Minas - Mestrado Profissional UFMG |
Programa de Pós-Graduação: |
Não Informado pela instituição
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Departamento: |
Não Informado pela instituição
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País: |
Não Informado pela instituição
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Palavras-chave em Português: | |
Link de acesso: | http://hdl.handle.net/1843/63476 |
Resumo: | Mineral Survey studies carried out by a minning company in the Morro do Calcário formation identified a new mineral body with occurrences of zinc and lead sulfides. The mining company has a mineral processing unit that concentrates galena and sphalerite minerals through the comminution, classification, flotation and filtration stages and produces three types of products: lead and zinc concentrates and flotation tailings, sold as agricultural limestone powder. In order to assess the feasibility of processing the new ore at the existing plant and keep its Zero Waste recognition, characterization studies of ore samples, bench and mini pilot scale flotation tests were carried out. The flotation tests were carried out using the standard process parameters of the existing plant, where the use of xanthate as a sulfide collector stands out, and additionally tests were carried out using new reagents to optimize results. In these tests, collectors of the dithiophosphinate type were used for the flotation of lead and dithiophosphate for the flotation of zinc, in addition to depressants for iron and zinc. The mineralogical characterization studies confirmed that the mineralogical matrixes of both ores are similar, with a predominance of dolomites as the gangue mineral, followed by pyrite and with the presence of sphalerite and galena as the main minerals. The main difference is in the proportion of minerals, highlighting the greater presence of pyrite in the new ore. The bench-scale and mini-pilot tests showed that the standard flotation system is not the ideal system for processing the new ore. The mini pilot scale tests in the standard process (PAX as a sulfide collector, lime, copper sulfate as a zinc activator, hexanol and octanol-based frother) confirmed the bench flotation tests, showing concentrate content lead of 16.50% and metallurgical recovery of 59.53%. The specification of lead quality has a minimum limit of 55%. In the zinc flotation, a zinc concentrate content of 50.73% was obtained, with a metallurgical recovery of 91.59% and an iron content of 5.71%. The iron specification in the zinc concentrate is 3.00% and the expected zinc content was 37.50%. Using the optimized flotation scheme determined by open bench tests (in lead flotation: dithiophosphinate, zinc sulfate, guar gum, DETA and in zinc flotation: dithiophosphate, copper sulfate, DETA, methyl isobutyl-based sparkling wine carbinol), it was possible to obtain high quality zinc concentrate with low iron contamination. It was obtained, in a mini pilot, a zinc content of 51.94% with recovery of 93.88%, and iron content of 2.74 % in zinc concentrate, whereas lead content of 51.35% and recovery of 67.75% were observed in the lead concentrate. The tailings obtained in the mini pilot tests met the specifications regarding cadmium and lead levels, as determined by the Ministry of Agriculture. The magnesium oxide content was above the specified limit and the calcium oxide proportion was slightly below the specification. |