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Mapeamento e estratégia de controle de cargas antrópicas potencialmente poluidoras da mineração de carvão de Moatize, Moçambique /Mafavisse, Isaías Mutombo. January 2018 (has links)
Orientador: Valquíria de Campos / Coorientador: Roberto Wagner Lourenço / Banca: Vidal Dias da Mota Junior / Banca: Paulo Sergio Tonello / Banca: Darllan Collins da Cunha e Silva / Banca: Nobel Penteado de Freitas / Resumo: A poluição do ar é considerada uma situação-tipo para o setor mineiro, apresentando aspectos clássicos de degradação do meio ambiente biótico e abiótico. O objetivo do trabalho é identificar áreas impactadas por material particulado da mineração do carvão e suas principais fontes emissoras em Moatize, propondo uma nova formulação de supressor de poeira de base vegetal como alternativa para reduzir a emissão de material particulado em mina a céu aberto. Através de metodologia cartográfica, buscou-se representar as áreas críticas contendo carga potencial poluidora, neste caso, partículas totais em suspensão (PTS) e material particulado respirável (MP10) procedentes do processo e logística da exploração do carvão. As variações na qualidade do ar em torno das áreas de mineração do carvão em Moatize foram avaliadas durante o período de 2015 em cinco locais e em duas estações do ano. Os dados de campo mostraram que as áreas mais impactadas pelas emissões difusas de partículas totais em suspensão (PTS) e material particulado com diâmetro 10 (MP10) devido à atividade de mineração do carvão em Moatize são Liberdade, Carbomoc, Minas Moatize e 25 de setembro. Este último é o mais impactado. Os dados revelaram ainda níveis de concentração de material particulado acima dos padrões estabelecidos no Regulamento de Normas de Qualidade Ambiental e Decreto de Emissão de Efluentes n° 67/2010 vigente em Moçambique. As concentrações de PTS atingiram 569 μg m-3 no mês mais crítico. As análises de... (Resumo completo, clicar acesso eletrônico abaixo) / Doutor
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Estudo do desempenho de barreiras de geotêxtil para contenção de sedimentos carreados pelo escoamento superficial /Lima Júnior, José Carlos. January 2014 (has links)
Orientador: George de Paula / Banca: Anna Silvia Palcheco Peixoto / Banca: Eduardo Bell'Avanzi / Resumo: O setor de mineração brasileiro experimentou um crescimento de produção de minérios sem precedentes nos últimos anos, impulsionado pelo cenário externo favorável em relação do setor da construção civil. Consequentemente, essas atividades além de gerarem grandes volumes de rejeitos tem cada vez mais ocupado extensas áreas ficando o solo superficial totalmente desprotegido. Isso tem provocado uma maior cobrança por parte da sociedade na questão da responsabilidade ambiental e social. Como resultado, as empresas de mineração têm sido fortemente cobradas no tocante às barreiras de rejeito e principalmente quanto ao escoamento superficial de modo a proteger os recursos hídricos. Atualmente realizam-se estudos para a diminuição da contaminação de recursos hídricos em desaguamentos de rejeitos. Neste contexto, o material que vem dando resultados de qualidade e eficiência é o geotêxtil, por apresentar funções que possam ser usadas para a diminuição dos impactos. Este trabalho analisa o comportamento da barreira geotêxtil para contenção de sedimentos provindo do escoamento superficial de uma pedreira. O estudo analisou o comportamento de dois geotêxteis com diferentes gramaturas em função da respectiva abertura de filtração aparente. Para avaliar o desempenho do geotêxtil foi construído um modelo físico em laboratório de modo a avaliar o volume retido e do volume que passa, assim como, sua eficiência. Os resultados indicam que retenção do rejeito, o geoxtêxtil de menor gramatura e geotêxtil de maior gramatura apresentaram um comportamento uniforme no início devido ao agulhamento, embora o geotêxtil reutilizado de menor gramatura apresentou um maior eficiência em relação ao tempo que leva para que o rejeito não fique retido na barreira. O geotêxtil de menor gramatura apresentou uma maior eficiência quanto ao tempo de retenção embora u ma maior parcela de finos tenha passado. O geotêxtil com... / Abstract: The brazilian mining industry experienced a growth of one production unprecedented in recent years, driven by favorable external scenario regarding the construction sector. Consequently, in addition to these activities generate large volumes of waste has increasingly occupied extensive areas getting totally unprotected topsoil. This has led to greater demand from society on the issue of environmental and social responsibility. As a result, mining companies have been heavily charged in respect of ensuring the barriers associated tailing and mostly about the runoff to protect water resources. Currently studies are conducted to reduce the contamination of water resources drainages tailings. In this context, the material that has been providing quality results and efficiency is the geotextile by the presenting functions that can be used for the mitigation of impacts. This paper analyzes the behavior of geotextile barrier for containment of sediment runoff stemmed from a quarry. The study analyzed the behavior of two geotextiles with different weights depending on their opening apparent filtration. To evaluate the performance of the geotextile a physical model has been built in the laboratory in order to evaluate the retentate volume and the volume that passes, as well as as its efficiency. The result indicate that for filtration and retention of the refuse, the geotextile ligher weight and greater weight had a uniform behavior at the beginning due to the needling, although geotextile reusable ligher weight had a greater efficiency compared to the time it takes to that the waste does not become trapped in the barrier. The geotextile lighter weight showed greater efficiency on the retention time although a larger proportion of fines has passed. The geotextile retains a heavier weight thinner but retained volume reaches the quota limit of basins with less time / Mestre
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Obtenção de um ataque químico padrão, zona de annealing parcial e temperatura de fechamento para o epídoto através do método dos traços de fissão /Nakasuga, Wagner Massayuki. January 2014 (has links)
Orientador: Carlos Alberto Tello Sáenz / Co-orientador: Eduardo Augusto Campos Curvo / Banca: Julio Cesar Hadler Neto / Banca: Silvio Rainho Teixeira / Banca: Sergio Roberto de Paulo / Banca: Neri Alves / O Programa de Pós Graduação em Ciência e Tecnologia dos Materiais, PosMat, tem caráter institucional e integra as atividades de pesquisa em materiais de diversos campi / Resumo: Durante os anos 1970 e 1980 pesquisadores da comunidade de traços de fissão discutiram os problemas relacionados à inclusão do mineral epídoto nesta metodologia, pois haviam discrepâncias significativas entre resultados apresentados pelos laboratórios/pesquisadores. Os debates não levaram a nenhuma definição clara sobre as condições de ataque químico para a revelação dos traços de fissão, bem como, da temperatura de apagamento total dos traços. Por fim, estes problemas culminaram no abandono dos estudos sobre este mineral dentro da metodologia por traços de fissão por um longo período de tempo. A fim de trazer à tona os estudos com este mineral, foram adquiridas 11 amostras de epídotos através de transações comerciais e/ou fornecidas por pesquisadores. Essas amostras formaram o grupo inicial para os estudos de ataque químico, datação e annealing deste trabalho. Após estudos sistemáticos, está sendo sugerido um ataque químico padrão de HF 40% a 15ºC por 80 minutos para epídotos com composição química Ca2Al2(A1, Fe3+)(SiO4)(Si2O7)O(OH). Ainda foram datadas 3 amostras das 11 do grupo inicial de epídoto. Essas amostras são da região do Rio Grande do Norte-Brasil, e as idades obtidas, como resultado, se mostraram compatíveis entre si. Também, foram obtidos 12 pontos de annealing (medidas de densidades superficiais e comprimentos reduzidos), 4 para o tempo de 1 hora (250, 300, 425 e 475ºC), 4 para 10 horas (250, 300, 430 e 510ºC) e mais 4 para 1000 horas (350, 500, 600 e 670ºC). Isto, tanto em densidade como em comprimento reduzidos. No caso da densidade, em cada ponto, foram analisados por volta de 100 campos e no caso do comprimento de traços confinados 100 traços medidos. Com o conjunto de dados de annealing apresentado no mestrado desde doutorando (Nakasuga 2010) mais os obtidos nesta tese pôde-se ajustar as curvas de annealing utilizando os modelos cinéticos de Guedes et. al. (2004) e... / Abstract: During the 70 and 80's researchers of fission tracks is discussed about issues related to inclusion of epidote mineral in this methodology because they had significant discrepancies between results reported by the laboratories/researches. The discussions did not lead to any clear definition of the conditions of etching for the development of fission tracks, as well as the temperature of the total fading of one. Finally, these problems resulted in the abandonment of the studies on this mineral in the method of fission tracks for a long period of time. In order to bring out studies with epidote, 11 samples epidotes were acquired through purchases or provided by researchers. These samples formed the initial group for studies of etching, dating and annealing of this work. After systematic studies, a standard etching has been suggested it is 40% HF at 15ºC for 80 minutes for epidotes with chemical composition Ca2Al2(Al,Fe3+)(SiO4)(Sl2O7)O(OH). Although 3 of the 11 samples of the inicial group of epidote were dated. These samples are from Rio Grande do Norte, Brazil region and the ages obtained, as a result, proved compatible among them. Moreover, 12 points annealing (measured surface densities and reduced length) 4 for 1 hour time (250, 300, 425 and 475ºC), 4 hours for 10 (250, 300, 430 and 510ºC) and another 4 for 1000 hours (350, 500, 600 and 670ºC) were made. This, in both reduced density and length of fission tracks. In case the density at each point, were analyzed around 100 fields and in the case the length of fission tracks 100 are confined measured. In the annealing data set shown in Nakasuga (2010) and the made in this thesis were adjusted annealing curves using the kinetic m odels Guedes et. al. (2004) and Lizandrão-Filho (2014). The result led to zones of Partial Annealing of 190-370ºC for data Nakasuga (2010) and 270-440ºC for the data made in this thesis, both for the period of 1 milion years. Through the Corsini et. al... / Doutor
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Planning and development of mining towns in Ghana: an exploration of mining and urban development frameworks and practicesGyogluu, Sarah January 2013 (has links)
Thesis submitted in fulfillment of the requirements for the degree
Master of Technology: Town and Regional Planning
in the Faculty of Informatics and Design
at the Cape Peninsula University Of Technology
2013 / Ghana has had a long history of mining especially with respect to gold, dating back to the Trans-Saharan Trade where gold precipitated civilisations and was a main commodity of trade among Europeans, merchants and ancient kingdoms. In the 21st century, globalisation coupled with increasing urbanisation has been driving demand for mineral resources and thus the resurging commodity booms. This increases foreign direct investment (FDI) in mining countries like Ghana resulting in not only growth in gross domestic product (GDP) but impacts that transcend macro-level and have direct and indirect impacts on communities in mining regions. The result is often that livelihoods are altered, spin-offs on the local economy emerge and the attendant settlement functions impact on the efficacy of existing mining and development planning and regulatory frameworks. Tarkwa is one of Ghana’s traditional gold mining towns and is the substantive context of the research.
The main objectives of the research were:
To identify the existing key mining and development planning regulations, gaps present and how these have impacted on the efficacy of governments management practices in responding to consequences of mining-led development.
To analyse the urban household’s perceptions of mining impacts on livelihoods, business enterprises and livelihood coping strategies and mechanisms.
To assess the implications of these emerging planning and development frameworks and trends for the effective planning and development of mining towns in Ghana
The highlights of the findings of the research in relation to the above objectives included:
The research revealed that urban households’ perception of mining on their livelihoods was mixed. One of the perceived negative impacts of mining that stuck out from overall responses was scarcity of land for purposes of farming and building.
With respect to coping with mining impacts, respondents largely employed a combination of assets to survive the mining environment. However, respondents’ dependence on human capital-that is, their ability to work and generate income underpinned all livelihoods capitals.
Over 96 percent of business enterprises, perceived purchasing power of people and related available or potential market as the most positive spin-off from mining yet. The informal economy was dominant in terms of business enterprise ownership with informal trading as the most principal form of business enterprise in the informal economy.
The research findings have significant meaning within the broad context of mining-led urban development and with implications for theory, the development and planning for resource-driven settlements (practice) and for further research. For example, with regard to development and planning practice, some glaring challenges include the lack of a proper land management system, “superiority” of some institutions (mine houses)in dealing with the Town and Planning Department and Municipal Assembly, lack of effective collaboration between related institutions, gaps in planning legislations make planning near impossible in Tarkwa.
The effect being that Tarkwa is growing (spatially to accommodate businesses and people coming in) but without an effective and responsive development planning system to effectively channel and coordinate this growth so that long term development is sustained.
The study concludes and recommends that, there is need for a rethink in the way mining towns are planned for and developed in Ghana and should include: a review of the Minerals and Mining law (Act 703) to engender more rights and protection to the communities, a constant review of concession and other agreements to reflect a constantly changing world order, institutional collaboration for planning and development, and long term planning which synchronises spatial and economic planning to capture advantages of agglomeration in and around the Tarkwa mining region.
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Challenges and prospects for small-scale mining entrepreneurs in South AfricaMkubukeli, Zandisile January 2016 (has links)
Thesis (MTech (Business Administration))--Cape Peninsula University of Technology, 2016. / Small-scale mining entrepreneurs are confronted with a variety of challenges during both the start-up and growth phase of their businesses not only in South Africa, but all over the world. Most small-scale mining entrepreneurs are not able to take advantage of the opportunities that are available to them. This retards the growth of their businesses. The aim of this study was to investigate the challenges and prospects for small-scale mining entrepreneurs in South Africa, the support structures available to them as well as the factors that could make them successful. The research problem in this study is that the mining sector is biased towards more established companies and against small-scale mining entrepreneurial operations, which marginalises small-scale mining entrepreneurs. Despite being a significant source of revenue for South Africa, the mining sector does not directly benefit the historically disadvantaged people. Notwithstanding government interventions, small-scale mining entrepreneurs face numerous challenges during both the business start-up and growth phase of their businesses with very few prospects of succeeding. This is a qualitative study that uses a series of face-to-face interviews with mining entrepreneurs in South Africa to generate data. Given that small-scale mining entrepreneurs are in most cases part of the informal sector and difficult to locate, a database of small-scale mining entrepreneurs was obtained from Mintek. Initially, 21 small-scale mining entrepreneurs were randomly selected to participate in this study. However, it soon became apparent that ten of them were no longer in business. This meant that the sample was reduced to eleven mining entrepreneurs, located in four provinces: Free State, KZN, Mpumalanga and Limpopo. The findings of this research reveal that small-scale mining entrepreneurs are handicapped by a lack of financial and technical resources, and therefore cannot purchase capital items. It seems that there are good prospects for small-scale mining, particularly in open markets. However, they are unable to exploit these prospects because they lack the necessary
finance. Although there are support structures to assist them, they find it difficult to meet the criteria for loans or overdraft facilities from financial institutions. Although these mining entrepreneurs have benefited from the support they have received thus far, they need equipment and commitment to their businesses to remain successful. A series of recommendations are made to guide small-scale mining entrepreneurs already in business, prospective small-scale mining entrepreneurs and other stakeholder’s interested in transforming the industry. / Zandisile Holdings (Pty) Ltd
National Research Foundation
Mauerberger Foundation
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Cost effective rehabilitation of an open cast chrome mine in the North West ProvinceCrous, Nadia Catharina 09 February 2009 (has links)
M.Sc.
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The microbial ecology of sulphidogenic lignocellulose degradationClarke, Anna Maria January 2007 (has links)
Acid mine drainage is a well known environmental pollutant, not only in South Africa, but throughout the world, and the use of microbial processes in the treatment of these wastes has been the subject of investigation over past decades. Lignocellulose packed-bed reactors have been used in passive treatment systems, and, although effective initially, they show early decline in performance while the packing material remains largely un-utilized. Little is known about this phenomenon which remains a severe constraint in the development of efficient passive mine water treatment systems. It has been proposed that the degradation pathways of the complex lignocellulose substrate may be limited in some way in these systems during the manifestation of this effect. This study has addressed the problem using a molecular microbial ecology methodology in an attempt to relate trophic functions of the microbial population to the physico-chemical data of the system. A field-scale lignocellulose packed-bed reactor located at Vryheid Coronation Colliery (Northern Kwa-Zulu Natal province, South Africa) was monitored for six years and the results showed the classic profile of performance decline related to a slowdown in sulphate reduction and alkalinity production. The reactor was decommissioned , comprehensive samples were collected along the depth profile and the microbial populations investigated by means of 16S rRNA gene methodology. The population was found to include cellulolytic Clostridia spp., CytophagaIFlavobacterlBacteroidetes, Sphingomonadaceae and as yet uncultured microorganisms related to microbiota identified in the rumen and termite gut. These are all known to be involved as primary fermenters of cellulose. Oesulphosporosinus was present as sulphate reducer. A comparison of substrata sampling and population distribution suggested that spatial and temporal gradients within the system may become established over the course of its operation. Based on these findings, a laboratory-scale reactor was constructed to simulate the performance of the packed-bed reactor under controlled experimental conditions. The laboratory-scale reactor was operated for 273 days and showed comparable performance to that in the field in both biomolecular and physicochemical data. Clearly defined trophic niches were observed. These results suggested that a sequence of events does occur in lignocellulose degradation over time. Based on the spatial and temporal column studies, a descriptive model was proposed to account for these events. It was found that fermentative organisms predominate in the inlet zone of the system using easily extractable compounds from the wood, thus providing feedstock for sulphate reduction occurring in the succeeding compartments. Production of sulphide and alkalinity appears to be involved in the enhancement of lignin degradation and this, in turn, appears to enhance access to the cellulose fraction. However, once the readily extractables are exhausted, the decline in sulphide and alkalinity production leads inexorably to a decline in the overall performance of the system as a sulphate reducing unit operation. These observations led to the proposal that with the addition of a limited amount of a readily available carbon source, such as molasses, in the initial zone of the the reactor, the ongoing generation of sulphide would be sustained and this in turn would sustain the microbial attack on the lignocellulose complex. This proposal was tested in scale-up studies and positive results indicate that the descriptive model may, to some extent, provide an account of events occurring in these systems. The work on sustaining lignocellulose degradation through the maintenance of sulphate reduction in the initial stages of the reactor flow path has led to the development of the Degrading Packed-bed Reactor concept and that, has subsequently been successfully evaluated in the field.
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Nationalisation : the nationalisation enquiry in light of Section 25 of the South African ConstitutionChauke, Tshikani Olivia 14 July 2015 (has links)
LL.M. / This is the exploration of the topic of nationalisation of the country’s mines and mineral wealth. The discussion studies the impact of the Minerals and Petroleum Resources Development Act 28 of 2002 (hereafter referred to as the MPRDA) and other relevant legislation on the nationalisation discussion. Ultimately the discussion examines whether nationalisation finds any support within the South African Constitution or not. The discussion begins with a study of the history of mining and minerals rights; an exploration is then undertaken on the meaning of property and whether mineral rights can be understood to mean property. The discussion then progresses to the study of the relevant provisions of section 25 of the South African Constitution in an effort to determine whether nationalisation is justifiable in terms of the South African Constitution. What is largely considered in this case are the recent findings of the Agri South Africa v Minister for Minerals and Energy 2013 4 SA 1 CC case as well as other relevant and emerging case law on the subject matter.
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Structural geologic controls at the San Luis Mines, Tayoltita, Durango, MexicoBallard, Stanton Neal, Ballard, Stanton Neal January 1980 (has links)
No description available.
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The geology of the Contention Mine area, Twin Buttes, ArizonaHouser, F. N. (Frederick Northrop), 1924-, Houser, F. N. (Frederick Northrop), 1924- January 1949 (has links)
No description available.
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