EM - Escola de Minas
URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6
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A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.
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Item Characterization of magnetic tailings from phosphate-ore processing in Alto Paranaíba.(2023) Silva, Fernando Brandão Rodrigues da; Araújo, Fernando Gabriel da Silva; Krüger, Fernando Leopoldo von; Silva, Guilherme Jorge Brigolini; Batista, Ronaldo Junio Campos; Manhabosco, Taíse MatteThe characterization studies of tailings from mining are crucial for the development of its reuse processes and the reduction of impacts caused by its conditioning on the earth’s surface. This study characterizes the magnetic tailings from phosphate-rock processing using X-ray diffraction, X-ray fluorescence spectrometry and quantitative electron microscopy techniques. Samples were obtained from the magnetic tailings deposit of a mining company in the Alto Paranaíba region, Minas Gerais. The tailings are mainly composed of hematite/magnetite (74.92%), ilmenite (8.91%), fluorapatite (8.8%), anatase (3.07%), calcite (1.67%), goethite (1.62%), and quartz (1.02%). The particle size of the tailings is smaller than that specified for the production of sinter feed. The hematite/magnetite phase is strongly associated with ilmenite and fluorapatite. New stages of comminution and separation are needed due to the low degree of liberation of these minerals for a possible reuse of the components.Item Mineralogical characterization of iron ore tailings from the Quadrilatero Ferrifero, Brazil, by Eletronic Quantitative Mineralogy.(2019) Ávila, Kelly de Souza Pires; Mendes, Jefferson Januário; Figueiredo, Vinícius Costa; Silva, Fabiane Leocádia da; Krüger, Fernando Leopoldo von; Vieira, Cláudio Batista; Araújo, Fernando Gabriel da SilvaThe mineralogical characterization studies search for the best processing route, with the lowest environmental impact, aiming to improve the use of mineral resources. The electronic quantitative mineralogy (EQM) provides quickly and accurately great information about the characteristics of these materials. This work aims to characterize iron ore tailings by EQM as the main tool. It has selected seven samples of itabirite ores flotation tailings from the main mining regions of the Quadrilatero Ferrifero, Brazil. All samples were mostly composed by quartz and iron minerals, with a low presence of mixture particles of these minerals - less than 20% of the sample mass. Due to the difference between the size of particles of quartz and iron minerals, it has observed an opportunity to reprocess the fractions -37μm + 5μm of the studied tailings, with a potential recovery of 12% of the total sample mass generated for AM4, AM6 and AM7 and more than 5% for samples AM1, AM2, AM3 and AM5.Item Comparison between hydroxyapatite/soapstone and hydroxyapatite/ reduced graphene oxide composite coatings : synthesis and property improvement.(2021) Nicomedes, Daniel Nilson Nunes; Mota, Laureana Moreira; Vasconcellos, Rebecca; Medrado, Nathanael Vieira; Oliveira, Michelle de; Alvarenga, Érika Lorena Fonseca Costa de; Juste, Karyne Ramos de Campos; Righi, Ariete; Manhabosco, Sara Matte; Silva, Guilherme Jorge Brigolini; Araújo, Fernando Gabriel da Silva; Oliveira, Alan Barros de; Batista, Ronaldo Junio Campos; Soares, Jaqueline dos Santos; Manhabosco, Taíse MatteEconomic viability and eco-friendliness are important characteristics that make implants available to the pop- ulation in a sustainable way. In this work, we evaluate the performance of a low-cost, widely available, and eco- friendly material (talc from soapstone) relative to reduced graphene oxide as reinforcement to brittle hy- droxyapatite coatings. We employ a low-cost and straightforward technique, electrodeposition, to deposit the composite coatings on the titanium substrate. Corrosion, wear, and biocompatibility tests indicate that the reduced graphene oxide can be effectively replaced by talc without reducing the mechanical, anticorrosion, and biocompatible composite coatings properties. Our results indicate that talc from soapstone is a promising ma- terial for biomedical applications.Item Decrepitation of Brazilian manganese lump ores.(2010) Faria, Geraldo Lúcio de; Viana, Nívea Cristina da Silva; Jannotti Júnior, Nelson; Vieira, Cláudio Batista; Araújo, Fernando Gabriel da SilvaA common problem in the production of ferromanganese alloys is the lack of knowledge about the mineralogical and metallurgical properties of the manganese lump ores. An important quality parameter of the lump ores is the decrepitation, which has not been studied adequately yet. This work presents physical, chemical and mineralogical characterizations of manganese lump ores from the three main Brazilian mines, Azul, Morro da Mina and Urucum, as well as their decrepitation behaviors. The samples, after characterization, were separated in three batches, one as received, the second after drying at 105°C, and the third after thermal treatment at 200°C. They were then tested for decrepitation at the temperature of 700°C for 30 min, with the particle size range kept between 19 and 6.3mm. The influence of the thermal history was studied together with the influence of the typological classifications of the ores, i.e., anhydrous-oxide for Urucum, hydrated-oxide for Azul, silicatecarbonate for Morro da Mina. A significant difference amongst the decrepitation behaviors was observed for the lump ores from Azul, Urucum and Morro da Mina. The oxide ores from Urucum (- 6.3mm = 10%) and Azul (-6.3mm = 6%) present a high susceptibility to decrepitation, whilst the silicate-carbonate from Morro da Mina shows no decrepitation. The presence of moisture increased the decrepitation intensity of the Azul and Urucum lump ores. The bench-scale thermal treatment reduced in more then 60% the decrepitation indexes of both ores.Item Characterization of manganese alloy residues for the recycling of FeSiMn and high-carbon FeMn fines.(2008) Faria, Geraldo Lúcio de; Reis, Érica Linhares; Araújo, Fernando Gabriel da Silva; Vieira, Cláudio Batista; Krüger, Fernando Leopoldo von; Jannotti Júnior, NelsonCrushing residues of FeSiMn and high-carbon (HC) FeMn alloys were characterized in order to evaluate their recycling possibility. Particle size determination was performed by screening, followed by chemical analysis of each particle size range using plasma spectrometry (ICP-AES). The slag content was identified and quantified by optical microscopy. All of the fines with grain sizes above 1.18 mm presented alloy contents in excess of 99 wt. (%) and were determined to need no further concentration prior to recycling. However the contents of Mn, Fe, Si and P in the fraction below 1.18 mm did not meet the chemical specifications for commercial manganese alloys, except for phosphorous. Optical microscopy of the fraction below 1.18 mm, showed that 87.95% of the FeSiMn corresponded to the alloy and that the slag content was 12.05%. For the HC-FeMn sample, 95.07% corresponded to the alloy and only 4.93% to the slag. These results revealed potential for gravity concentration and recycling, reducing the residues in about 95% and improving the process productivity.Item Caracterização de uma tipologia de minério de manganês do Brasil.(2010) Reis, Érica Linhares; Faria, Geraldo Lúcio de; Araújo, Fernando Gabriel da Silva; Tenório, Jorge Alberto Soares; Vieira, Cláudio Batista; Jannotti Júnior, NelsonVisando a melhorias no benefi ciamento e no processo de fabricação de ferroligas de manganês, foi realizada a caracterização de uma tipologia predominante de minério de manganês, de ocorrência na região de Carajás, PA, BR. Obteve-se uma amostra representativa da tipologia e foram realizadas análise granulométrica por peneiramento e análise química, por ICP-AES. Foram identifi cadas por difratometria de raios X as fases minerais majoritárias. Um estudo termogravimétrico foi desenvolvido para verifi car a estabilidade térmica, ao ar, das fases minerais majoritárias. Observou-se que 19,3% da amostra encontram-se abaixo de 6,3mm. O teor de manganês no minério foi de 52,63% em peso, com 1,92% de sílica, 0,17% de fósforo e 3,13% de ferro. Foram identifi cados, na amostra, os óxidos de manganês criptomelana, todorokita e pirolusita, com goethita, quartzo, gibbisita e caolinita compondo a ganga. Para a amostra estudada, observou-se a decomposição térmica dos óxidos criptomelana e pirolusita, em torno de 600oC, ao ar. Em torno de 950oC, teve início a transformação de Mn2O3 em Mn3O4.