Uma Abordagem De Mapeamento De Potencial Mineral Dos Depósitos De Níquel Supérgeno Do Sudeste Do Cráton Do São Francisco

Southwestern Sao Francisco Craton makes limit with Braslia thrust-fold belt and involves rocks from Archean to formed during the Brasiliano-Pan Africano Neoproterozoic event, including a mafic-ultramafic belt (Morro do Ferro Greenstone Belt) hosted along the Archean counterpart. This greenstone belt hosts two-nickel deposits (Morro do Niquel and O'Toole, respectively silicate and sulfide types) and occurrences. This study applies an empirical-conceptual model for lateritic nickel deposits formation into geographic information systems with aerogeophysical data (magnetic and gamma-spectrometry) and digital elevation models (terrain relief and slope). Our contribution aims for nickel deposits favorability mapping using a simple mathematical operator over a supporting spatial database translating the conceptual exploration model into evidential layers for geological processes involved on deposit formation. Evidential layers constructed for identification of elements pertaining the supergene nickel mineral system are given by analytic signal amplitude maps, thorium over potassium ratio images, and digital elevation models and slope maps, derived from shuttle radar topography mission digital elevation models. Evidential layers integration through binary layers algebraic sum identified effectively known deposits and occurrences with its outputs highlighting possibilities for unknown resources in this under-explored terrain.46226127

Uma abordagem de mapeamento de potencial mineral dos depósitos de níquel supérgeno do sudeste do Cráton do São Francisco

Southwestern São Francisco Craton makes limit with Brasília thrust-fold belt and involves rocks from Archean to formed during the Brasiliano-Pan Africano Neoproterozoic event, including a mafic-ultramafic belt (Morro do Ferro Greenstone Belt) hosted along the Archean counterpart. This greenstone belt hosts two-nickel deposits (Morro do Níquel and O'Toole, respectively silicate and sulfide types) and occurrences. This study applies an empirical-conceptual model for lateritic nickel deposits formation into geographic information systems with aerogeophysical data (magnetic and gamma-spectrometry) and digital elevation models (terrain relief and slope). Our contribution aims for nickel deposits favorability mapping using a simple mathematical operator over a supporting spatial database translating the conceptual exploration model into evidential layers for geological processes involved on deposit formation. Evidential layers constructed for identification of elements pertaining the supergene nickel mineral system are given by analytic signal amplitude maps, thorium over potassium ratio images, and digital elevation models and slope maps, derived from shuttle radar topography mission digital elevation models. Evidential layers integration through binary layers algebraic sum identified effectively known deposits and occurrences with its outputs highlighting possibilities for unknown resources in this under-explored terrain.Southwestern São Francisco Craton makes limit with Brasília thrust-fold belt and involves rocks from Archean to formed during the Brasiliano-Pan Africano Neoproterozoic event, including a mafic-ultramafic belt (Morro do Ferro Greenstone Belt) hosted along462261273sem informaçãosem informaçãoA região sudeste do estado de Minas Gerais encontra-se no limite do Cráton do São Francisco com um sistema de dobras, empurrão e cisalhamento formados no Neoproterozóico no evento Brasiliano-Pan Africano, com envolvimento de assembleias do arqueano até esAluno de doutorad

Advanced Techniques and Efficiency Assessment of Mechanical Processing

Mechanical processing is just one step in the value chain of metal production, but to some exten,t it determines an effectiveness of separation through suitable preparation of the raw material for beneficiation processes through production of required particle sze composition and useful mineral liberation. The issue is mostly related to techniques of comminution and size classification, but it also concerns methods of gravity separation, as well as modeling and optimization. Technological and economic assessment supplements the issue

Pattern Recognition

A wealth of advanced pattern recognition algorithms are emerging from the interdiscipline between technologies of effective visual features and the human-brain cognition process. Effective visual features are made possible through the rapid developments in appropriate sensor equipments, novel filter designs, and viable information processing architectures. While the understanding of human-brain cognition process broadens the way in which the computer can perform pattern recognition tasks. The present book is intended to collect representative researches around the globe focusing on low-level vision, filter design, features and image descriptors, data mining and analysis, and biologically inspired algorithms. The 27 chapters coved in this book disclose recent advances and new ideas in promoting the techniques, technology and applications of pattern recognition

Densification of spatially-sparse legacy soil data at a national scale: a digital mapping approach

Digital soil mapping (DSM) is a viable approach to providing spatial soil information but its adoption at the national scale, especially in sub-Saharan Africa, is limited by low spread of data. Therefore, the focus of this thesis is on optimizing DSM techniques for densification of sparse legacy soil data using Nigeria as a case study. First, the robustness of Random Forest model (RFM) was tested in predicting soil particle-size fractions as a compositional data using additive log-ratio technique. Results indicated good prediction accuracy with RFM while soils are largely coarse-textured especially in the northern region. Second, soil organic carbon (SOC) and bulk density (BD) were predicted from which SOC density and stock were calculated. These were overlaid with land use/land cover (LULC), agro-ecological zone (AEZ) and soil maps to quantify the carbon sequestration of soils and their variation across different AEZs. Results showed that 6.5 Pg C with an average of 71.60 Mg C ha–1 abound in the top 1 m soil depth. Furthermore, to improve the performance of BD and effective cation exchange capacity (ECEC) pedotransfer functions (PTFs), the inclusion of environmental data was explored using multiple linear regression (MLR) and RFM. Results showed an increase in performance of PTFs with the use of soil and environmental data. Finally, the application of Choquet fuzzy integral (CI) technique in irrigation suitability assessment was assessed. This was achieved through multi-criteria analysis of soil, climatic, landscape and socio-economic indices. Results showed that CI is a better aggregation operator compared to weighted mean technique. A total of 3.34 x 106 ha is suitable for surface irrigation in Nigeria while major limitations are due to topographic and soil attributes. Research findings will provide quantitative basis for framing appropriate policies on sustainable food production and environmental management, especially in resource-poor countries of the world

Energy-Efficiency of Conveyor Belts in Raw Materials Industry

This book focuses on research related to the energy efficiency of conveyor transportation. The solutions presented in the Special Issue have an impact on optimizing, and thus reducing, the costs of energy consumption by belt conveyors. This is due, inter alia, to the use of better materials for conveyor belts, which reduce its rolling resistance and noise, and improve its ability to adsorb the impact energy from the material falling on the belt. The use of mobile robots designed to detect defects in the conveyor's components makes the conveyor operation safer, and means that the conveyor works for longer and there are no unplanned stops due to damage

Hihnan päällä toimivan optisen 3D-granulometriajärjestelmän mekaanisten oheislaitteiden kehitys

This thesis presents the process of designing the mechanical structure for a commercial particle size analyzer of granular material based on on-line 3D optical granulometry technology. The analyzer can be used to monitor and increase the performance of various processes within the mining, mineral, and metal industry (MMMI), particularly grinding processes that utilize autogenous and semi-autogenous grinding mills. The analysis system contributes to the evolution of the MMMI in a more energy efficient direction, resulting in a decreased ecological footprint of the industry as well as financial benefits for the operators. The design work done for this thesis contributes to a product development project by Outotec, a technology company specializing in the MMMI. Prior work within the project included a detailed business analysis and software development. A systematic methodology to carry out the design work was derived from the field of engineering design literature. The methodology is based on decomposition of the design problem into smaller subproblems. By finding solutions for each subproblem individually, an overall conceptual solution is produced. This methodology was used to create explicit engineering parameters and a conceptual solution for the mechanical structure of the product, based on the prior work done on the product development project. The conceptual solution was then defined further into a complete mechanical design and a functional prototype. The prototype was tested and evaluated based on the engineering parameters. Based on the results, a second iteration of the design was created, improving on the initial design. Based on objective evaluation of the second design iteration, the design meets all the criteria set for the product development project and can be taken to market. However, the evaluation and further iteration of the design will continue after product launch based on customer feedback and product performance.Tämä diplomityö esittelee optiseen 3D granulometriateknologiaan perustuvan kaupallisen partikkelikokoanalysaattorin mekaanisen suunnitteluprosessin. Analysaattorin pääasiallinen käyttötarkoitus liittyy kaivosteollisuuden erinäisten prosessien monitorointiin ja ohjaukseen. Ensisijainen käyttökohde on autogeenisiä ja semiautogeenisiä myllyjä hyödyntävien jauhatusprosessien syöttömateriaalin monitorointi. Suunniteltu laitteisto edistää kaivosteollisuuden kehittymistä energiatehokkaampaan suuntaan ja siten toimialan aiheuttaman ekologisen jalanjäljen pienentämistä. Laitteen tarkoitus on myös tuottaa taloudellista hyötyä sekä kaivosteollisuuden operaattoreille että laitteen toimittajalle. Tämän diplomityö on tehty kaivosalalla toimivan teknologiayhtiön, Outotecin, toimeksiannosta ja edesauttaa erästä yhtiön tuotekehitysprojektia. Suunnittelutyö toteutettiin tuotekehitykseen liittyvästä kirjallisuudesta löydettyjä systemaattisia menetelmiä hyödyntäen. Käytetty suunnittelumetodiikka perustuu suunnitteluongelman jakamiseen pienempiin osatekijöihin. Suunnitteluongelma ratkaistaan löytämällä kullekin osatekijälle toimiva ratkaisu. Kyseiseen metodiikkaan sekä tuotekehitysprojektin aiempiin työpanoksiin perustuen tuotteelle luotiin yksikäsitteiset suunnitteluparametrit sekä mekaaninen konsepti. Konseptin pohjalta suunniteltiin tuotteen mekaaninen rakenne ja rakennettiin toimiva prototyyppi, joka testattiin aiemmin luotujen suunnitteluparametrien perusteella. Tulosten perusteella tuotteesta suunniteltiin toinen versio, jossa korjattiin testauksessa havaittuja puutteita. Toisen tuoteversion objektiivisen arvioinnin perusteella suunnittelutyön tavoitteisiin on päästy. Tämän arvion perusteella tuote täyttää kaikki sille asetetut kriteerit ja se voidaan viedä markkinoille. Tuotteen suorituskyvyn arviointi ja rakenteen iterointi jatkuu kuitenkin vielä markkinoille viennin jälkeen

Remotely Sensed, Geophysical and Geochemical Data as Aids to Mineral Exploration in Bahia State, Brazil

This thesis aims to establish methodological procedures to implement Geographical Information System (GIS) techniques applied to mineral exploration, in particular gold associated with an Archaean greenstone belt located in a semi-arid climate: - the Contendas-Mirante greenstone belt which is located in the southeastern part of Bahia State in northeastern Brazil. To achieve this goal a systematic approach was formulated. It begins with the correlation between Brazil and Africa. The geographical position of adjacent age-provinces, the coincidence of structural trends, their continuity in a pre-drift reconstruction and the similarities in the geochronological patterns, all indicate their correlation. A particular Brazilian portion of the South America Platform, termed the Sao Francisco craton, (SFC) became stabilised in the late Proterozoic (1800 Ma). In this crustal block the Archaean rocks include medium-grade (Gaviao Block) and high-grade (Jequie Block) terrains which form the infrastructure for a number of volcano-sedimentary or sedimentary sequences. One of these volcano-sedimentary sequences, the Contendas-Mirante belt (CMB), is located along the junction between the Gaviao and Jequie Blocks. It is divided into Lower Unit (mainly volcanogenic) and Upper Unit (essentially clastic). In the CMB the plutonic granitoid associations exhibit geochemical characteristics compatible with a continent-continent collision. The available data set for this area includes topographic and geological maps, stream sediment survey, Landsat TM and radar data, and airborne magnetic and radiometric surveys. The most suitable way for dealing with this enormous amount of data leading to mineral exploration exploration, is via GIS. Gold deposits can be distinguished according to depositional and genetic models. In this work I concentrate on the depositional model which can be divided according to the structural setting and lithological associations. From the available data set, the use of the Landsat TM data in lithological mapping was restricted by the vegetation and soil cover. However, TM data provided useful information on regional structures. Radar data were valuable for structural information and as ancillary data combined with radiometric data for lithological discrimination. The stream sediment reconnaissance was interpreted via a raster model. Several sets of very well correlated elements were defined: Fe-Cu-Co-As, Fe-As-Cr-V-Ba-Cu, Fe-Ni-Cu, Fe-Mg-Ti-Cu, Fe-Cu-As-Pb and Fe-Ba-As-Pb. From these element associations anomalous areas were defined. The magnetic data were useful for both the selection of zones with high magnetic fields and the detection of magnetic lineaments. The radiometric data in both small and large scale were valuable for lithological discrimination. The selected and diversified GIS functions generated a final product, called data fusion, which is far more sophisticated than data integration. The four selected areas for gold, which represent 12% of the total study area, and due to the convergent geological factors, have good potential for gold

Reflectance spectrum analysis of mineral flotation froths and slurries

The global demand of mining products has increased during recent years, and there is pressure to improve the efficiency of mines and concentration processes. This thesis focuses on froth flotation, which is one of the most common concentration methods in mineral engineering. Froth flotation is used to separate valuable minerals from mined ore that has been crushed, mixed with water and ground to a small particle size. The separation is based on differences in the surface chemical properties of the minerals. Monitoring and control of flotation processes mainly relies on the on-line analysis of the process slurry streams. Traditionally, the analysis is performed using X-ray fluorescence (XRF) analyzers that measure the elemental contents of the solids in the slurries. The thesis investigates the application of visual and near-infrared (VNIR) reflectance spectroscopy to improve the on-line analysis of mineral flotation froths and slurries. In reflectance spectroscopy the sample is illuminated and the spectrum of the reflected light is captured by a spectrograph. The main benefits of VNIR reflectance spectroscopy with respect to XRF-based analysis are the relatively low cost of the equipment required and the easy and fast measurement process. As a consequence, the sampling rate of the reflectance spectrum measurement is radically faster than in the XRF analysis. Data-based modeling is applied to the measured VNIR spectra to calculate the corresponding elemental contents. The research is conducted at a real copper and zinc flotation process. The main results of the thesis show that VNIR reflectance spectroscopy can be used to measure temporal changes in the elemental contents of mineral flotation froths and slurries in the analyzed process. Especially the slurry measurements from the final concentrates provide accurate information on the slurry contents. A multi-channel slurry VNIR analyzer prototype is developed in this thesis. When combined with an XRF analyzer, it is able to measure the slurry lines with a very fast sampling rate. This considerably improves the monitoring and control possibilities of the flotation process. The proposed VNIR analyzer is adaptively calibrated with the sparse XRF measurements to compensate for the effect of changes in other slurry properties. The high-frequency slurry analysis is shown to reveal fast grade changes and grade oscillations that the XRF analyzer is unable to detect alone. Based on the new measurement, a plant-wide study of the harmful grade oscillations is conducted in order to improve the performance of the flotation process