Dissertations / Theses: 'Copper mines and mining – Zambia'

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Chinyuku, Donald Tichaona. "The Kansanshi Cu-Au deposit, Domes region, Zambia : geology, mineralisation and alteration characteristics in the main pit." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1011758.

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The Kansanshi Cu-Au deposit located in the Domes region of the North West province of Zambia is characterised by structurally controlled high angle veins and associated alteration halos. The northwest trending Kansanshi antiform flanks the Solwezi syncline to the north and hosts the Kansanshi deposit and consists of tillites and metasedimentary rocks. Mineralisation is associated with Neoproterozoic Pan African deformation events experienced during the formation of the Lufilian fold belt; however recent findings confirm that structures in the form of reverse and normal faults and drag folds are critical controls on mineralisation within the deposit, Main pit in particular. Low angle faults occurring below the current pit are believed to have served as major fluid pathways during mineralisation. Age dating data from the Kansanshi deposit suggest that mineralisation took place between 512 and 503 Ma indicating that the event was associated with metamorphism. Two types of alteration are dominant within the Main pit (Kansanshi deposit) with the type and intensity of alteration being largely controlled by lithological units. Albite alteration occurs dominantly in phyllites and schists whereas dolomitisation is prevalent in calcareous units. Alteration is associated with mineralisation, and therefore is used as a condition for predicting vein or disseminated mineralisation. The high Au tenor at Kansanshi can be attributed to gold grains occurring in association with melonite (NiTe₂) and microfractured pyrite intergrown with chalcopyrite in sulphide and quartz dominated veins and veinlets. Analysis of gold grade distribution within the Main pit shows a clear concentration of the element along the major north-south trending structures like the 4800 and 5400 zones, possibly through supergene enrichment in the oxide-transition-sulphide zones. It is imperative that exploration for Kansanshi-type deposits will require geochemical and geophysical studies, understanding of the geology of an area to identify the three lithostratigraphic units (red beds, evaporites and reducing strata).

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Lukweza, Chishala. "An investigation into the state-of-practice of information security within Zambian copper mines: a case study." Thesis, Rhodes University, 2011. http://hdl.handle.net/10962/d1002776.

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Zambian copper mines have embraced the use of information technologies for strategic operations and competitive advantage. This dependence on these technologies has not only been seen in the physical aspects of business operations but also in the use of information systems such as Enterprise Resource Planning Systems (ERPs) for strategic decision making and increased usage of Industrial Control Systems (ICS’) that are meant to enhance operational efficiency in production areas. A survey was conducted to explore leadership perceptions on information security practices in Zambian copper mines and an ISO/IEC 27002 Audit Tool was administered to middle management in a particular mine for an in-depth analysis of their information security practices. Results revealed that although information security controls may have been put in place in these organisations, there are still areas that require attention. Senior management and middle management have different perceptions as to the extent to which information security practices are conducted in these copper mines. This implies that management may not be fully involved in certain aspects of these organisations’ information security practices. The results concluded that management needs to be fully involved and provide support for information security programs. Furthermore, these information security programs should be standardised so as to effectively protect these organisations’ information assets. This should also include the involvement of personnel as key players in the information security process.

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Kabunda, Ghislain Mwape. "Exploration for sediment-hosted copper mineralization in Kaponda Prospect, Central African Copperbelt, Democratic Republic of Congo." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1013129.

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The Kaponda Prospect represents a surface of 915.8 km² located at about 10 km south of the town of Lubumbashi and 33km NW of Kasumbalesa in the Democratic Republic of Congo (DRC). It lies within Neoproterozoic sedimentary rocks of the Katangan Supergroup in the Central African Copperbelt (CACB). In this province, copper mineralization occurs at different stratigraphic level with different associated alteration. Mineralization is of multistage origin from synsedimentary, diagenetic to post orogenic. Since the discovery of the CACB in the early 20th century, several exploration techniques have been used to delineate Cu deposits. A review and application of these methods including remote sensing, geological mapping, geochemical and geophysical surveys, and drilling, gives an insight of their effectiveness and limitation before analyzing their results from the Kaponda Prospect. The geology and structure of the Prospect is represented by a series of two NW trending disharmonic tight anticlines, locally domal, with cores occupied by either Roan Group or “Grand Conglomerat” Formation. These anticlines are separated by an open syncline made of Kundelungu rocks. Two mains direction of faults are recognized, the NW and NE trending structures. The latter direction are normal transfer faults which can serve as conduit for mineralization. They are related to the late orogenic extension of the Lufilian belt. However NE trending faults are believed to be associated to the climax of Lufilian folding or represents synsedimentary intergrowth faults. Exploration approach for sediment-hosted Cu within Kaponda Prospect, take into account the integration of all information derived from different techniques. Remote sensing is used as aid to geology. Landsat and Google earth images show lineaments that corresponds to lithostratigraphy boundary and domal anticline. Geological mapping identified reduced horizons which can potentially host mineralization, whereas analysis of structure measurements reveals the geometry of fold and direction of its axial plane and hinge. Statistical methods such as the main + 2 standard deviation, the frequency histogram and probability plot, together with experiential method are used to constrain and define Cu and Co thresholds values in soil samples. It appears that in this region, log-probability plot and histogram methods combined with spatial representation and the experience of the region, are the best practice to constrain and separate geochemical background from anomaly data. Ground and airborne magnetic, and radiometric images show specific signatures which map alteration and particularly lithostratigraphy such as “Roan” Group, “Grand Conglomerat” unit, “Nguba” cap carbonates and “Kundelungu” siliciclastic units. Analysis of faults interpreted from geophysical maps identified three major directions: E-W, NE-SW and NW-SE. The E-W faults are also interpreted as normal transfer faults such NE-SW structures, consistent with regional geological map. Although pole-dipole array of induced polarization (IP) survey was directly targeting disseminated Cu sulphide, its results suffer in responding to graphitic rocks and barren pyrite. Only relative small chargeable bodies need to be tested in drilling follow-up. A total of 15 targets have been generated through re-interpretation and integration of both geological mapping and remote sensing, geochemical and geophysical data, as well as existing drilling. Specific recommendations of follow-up works are advised for each type of target.

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Negi, Rohit. "Copper Capitalism Today: Space, State and Development in North Western Zambia." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1248715316.

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Mengwe, Moses Seargent. "Towards social impact assessment of copper-nickel mining in Botswana." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1443.

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This research study is more of an initiative towards Social Impact Assessment of copper-nickel mining in Botswana. The specific objectives of the study were centred on the assessment of the social impacts of copper-nickel mining in Botswana from the initial mining stage of exploration, surveying and mine site development to mine closure. The study was carried out under the broad hypotheses that mining influences population movement that impact on areas of mining; mining activities have both economic benefits and deleterious social impacts on the local communities found in the areas where mining is taking place; and mine closure has far reaching socio-economic, investment and developmental implications over and above the obvious interests of project owners. To achieve the broad aim as summarised above, the research study used a multi-disciplinary methodology and approach that required several kinds of expertise and sources of information. Hence it used both primary and secondary sources centred on interactive informative interviews, site visits and observations, questionnaires, census data records, mining companies’ publications, published textbooks and journal articles. The research study comprised of three different mines operated by three different mining companies in three varied socio-cultural and ethnic regions of Botswana. First was a detailed Social Impact Assessment of the initial phase of exploration, surveying and mine site development represented by Mowana mine project operated by African Copper in the rural areas of Dugwi and Mosetse. This case study yielded results showing that the social impacts of mining in the area are diverse and extensive. The findings suggest that the impacts relate not only to the possible economic benefits of foreign exchange, employment, the optimal use of available mineral resources and the possible development of Dugwi and Mosetse villages, but extends to the deleterious social impacts. The results also indicated that the social impacts have just begun in the two communities. Hence they point towards a possible disruption within the socio-cultural system of the local people if serious mitigation measures are not put in place; thus suggesting that the early stages of exploration and mine site development results in the most conflict between the mine and the local people. Second was a comprehensive Social Impact Assessment of Tati-Nickel Phoenix mining project in the peri-urban areas of Matshelagabedi and Matsiloje areas representing the mining stage of mine production and expansion. The results from this case study suggest that during vi mine production and expansion, many people were relocated. However, the overriding impression gained from the case study was Tati-Nickel Mining Company’s elaborate corporate policies that suggested good corporate governance and best practices that promote sustainable development. A notable milestone on good corporate governance and best practice that the other two case studies (mining company) could benchmark on is Tati-Nickel’s corporate social responsibility programme that has been designed to ensure that the communities within a fifty kilometre mine radius benefit from the mine. The results from the case study also distinguished the mining stage of production and expansion from the other two because it is associated with the deep entrenchment of the social impacts into the communities near to mining areas. Third was a detailed Social Impact Assessment on Bamangwato Concession Limited mine in the industrial town of Selebi-Phikwe. The case study represented the stage of mine closure. Through the findings of this case study, it became apparent that the economic dependence of Selebi-Phikwe on mining has seen the town developing into a mining town, increasing its vulnerability at mine closure. The results from the case study further suggest that mine closure will degrade the socio-economic sector of the town with ever far reaching socio-economic implications as many people lose their gainful employment, hence suggesting that a possible complete mine closure will be the most traumatic phase leading to major social conflict within the area. Thus the results suggest that at mine closure, the deleterious social impacts will overspill to other areas in Botswana with disastrous effects for the economy of the country. The results yielded through this study established in clear and passionate language that copper-nickel mining in Botswana influences population movements that lead to positive and negative impacts on the communities found in mining areas. Another major finding of the study is that copper-nickel mining activities have both economic benefits and deleterious social impacts on the local communities, hence the recommendation that the copper-nickel mining companies should embrace the concept of sustainable mining for sustainable development to avoid most of the negative impacts of their operations on the local communities.

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Kabanshi, Alan. "Energy Audit and Management : A case study of Konkola Copper Mines, Nchanga Mine-Zambia." Thesis, Högskolan i Gävle, Avdelningen för bygg- energi- och miljöteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-12816.

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The goal to satisfy the energy demand, global warming and other environmental effects has prompted the urgency to shift energy generation systems to more affordable and sustainable methods, with the goal of phasing out the traditional-conventional systems to environmental friendly and sustainable generation systems. This campaign also calls for a more energy conscious society aware of its energy demand and promoting energy efficiency so as to minimize the demand through reduced wastages. For the later to be achieved energy systems should be understood in organization and this involves performing energy audits. This paper discusses the energy audit of Nchanga mine, Nchanga mine is located in Chingola town in the Copperbelt province of Zambia, and has operations involving underground mining, copper leaching, open pit mining and concentrate extraction. The Objective of the study was to perform a preliminary Audit; to understand the energy scenario and identify areas were savings could be realized. The problem however was that constraints on time could not allow a detailed analysis hence the scope was strictly on a preliminary audit study with minimal details on economics of measures and no analysis of investment cost. The method used for this analysis was the top down approach and the processes were divided into support and production processes to establish the energy balance. Nchanga mine has an annual energy use of about 656 GWh with an average maximum demand of about 88.6 MW. The total cost was about US. $ 34 million with maximum demand (MD) covering about $ 22 million and the rest was energy costs. This was obtained from analysis of energy bills from April 2011 to March 2012. The energy measures analyzed were according to the cost; cost influenced and non-cost influenced. The non-cost influenced measures gave a saving potential of about 15.6 MW ($ 3.9 million) on MD and 46 GWh ($ 818,800) on energy, giving a total electricity cost saving of about $ 4.7 million. The cost influenced measures gave a saving potential of about 12.7 MW ($ 3.1 million) on MD and 12 GWh ($ 213,600) on energy, giving a total electricity cost saving of about $ 3.4 million. These measures have a potential to reduce the overall MD by 28 MW (32% reduction), realizing an annual saving of about $ 7 million, and the overall energy use by about 58 GWh (8.8% reduction), which is an annual saving of about $ 1 million. This gives the total saving on the electricity bill of about $ 8 million that is about 24% reduction on the electricity bill with regards to last year’s expenditure.

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Carr, Frank. "Government decision-making and environmental degradation : a study relating to mining activities in Papua New Guinea /." Carr, Frank (2007) Government decision-making and environmental degradation: a study relating to mining activities in Papua New Guinea. Masters by Research thesis, Murdoch University, 2007. http://researchrepository.murdoch.edu.au/502/.

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Papua New Guinea (PNG) is a country possessing abundant resources of gold, oil, copper, timber, and fish stocks. It is hampered in its development and management of these resources, however, by serious problems of governance and corruption. These problems are evident throughout the economy and also in the management of the environment. The level of environmental damage caused by the mining industry in PNG is now such that it will require extensive rehabilitation, if the areas affected can, indeed, ever be fully rehabilitated. The mining companies which precipitated this damage were licensed and encouraged by the PNG Government in the initiation and exercise of the mining operations. The resulting environmental impact has affected the lives of thousands of New Guineans to their detriment. The degradation caused remains unredressed. Compounding the problem, there is a growing reliance by Papua New Guinea on mineral exploitation for foreign direct investment, government revenues, and foreign exchange. Gold exports accounted for the biggest share of export revenues in 2002 representing 37.5% of the total. In light of this growing dependency on mining activities, there is a correspondingly urgent requirement to address the deficiencies in the administrative, monitoring, and policing aspects of the protection of its environment. Despite the public evidence of the damage to the environment and the ensuing affect on the people of Papua New Guinea by mining activities; and despite universal condemnation of these activities and the companies responsible; the companies continue to conduct these activities without official hindrance and with little apparent concern for the long-term ramifications of their actions. This thesis will examine the degradation resulting from the mining activities of companies in Papua New Guinea over the last three decades - particularly those of Placer Dome's Porgera gold mine, BHP's Ok Tedi gold and copper mine (the waste from both of which is dumped into the Ok Tedi and Strickland rivers which are tributaries of the Fly River and form part of the Fly River system) and Lihir Gold Limited's gold mine on Lihir Island. It will examine the extent to which the Government of Papua New Guinea may have wittingly (in the sense of a prescience as to the possible or probable likelihood of deleterious impact) or unwittingly contributed to that degradation as a result of its actions or omissions. Studies of available literature suggest that there has been little attention paid to the subject of culpability on the part of successive PNG governments in matters of environmental damage. This research will contribute to reducing this gap in the literature by focusing on possible motives of the PNG government and its actors which precipitated those decisions and which resulted in environmental degradation. The discussion will examine the likely motivation of the PNG government in its deliberations and decisions and the extent to which corruption and incompetence may have played a role.

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Altamirano, Nelson. "Essays on mining countries : Dutch disease, development and copper markets /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC IP addresses, 2000. http://wwwlib.umi.com/cr/ucsd/fullcit?p9975891.

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Fowler, Sandra Dee. "COPPER SOLVENT EXTRACTION FROM CHLORIDE-SULFATE MEDIA." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275369.

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Hovis, Logan W. "Technological change and mining labour : copper mining and milling operations at the Britannia mines, British Columbia, 1898-1937." Thesis, University of British Columbia, 1986. http://hdl.handle.net/2429/26539.

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Most recent studies of the relationship between technological change and mining labour in the western metal-mining regions of North America have concentrated on the impact of the mechanization of the industry that took place during the second half of the nineteenth century. The distinct impression is left that the increased use of machinery — especially the machine drill — was the chief factor in reducing the skill levels associated with mining as a craft tradition. Preoccupation with machinery has led to the assumption that by the beginning of the twentieth century the transformation to modern forms of mining was essentially complete and the traditional miner an anachronism. Mining as practiced prior to 1900 differed qualitatively and quantitatively from the subsequent period of "modern mining;" but the introduction of machinery per se was less important to the reorganization of the patterns of work in the mines than the redesigning of the engineering systems in which workers and machines were employed — a process which gained its full momentum in the decades after 1900. This transformation involved the gradual abandonment of low-volume, high-value, selective mining methods in favour of higher volume, non-selective methods which emphasised the quantity rather than the quality of the ore mined. The change redefined the nature of work in and around the mines, putting an end to a tradition of mining practice that was at least as old as the methods described in Agricola's De Re Metalica, something the initial mechanization of mining had never been intended to accomplish. Under selective mining practices, machinery was used to assist the skilled miner in his traditional task. Under non-selective or mass mining techniques, a new generation of engineers trained in the applied sciences redefined the miner's work as solutions were sought to the problems of an increasingly complex geology in a climate of rapid economic expansion, chronic over-production, generally declining metal prices, and ever increasing production costs. The efforts and successes of these engineers were amply demonstrated in the fields of mining, metallurgical, and human engineering. The impact of the change is evident in varying degrees throughout the metal-mining community; but by focusing on copper mining — the technological leader from 1900 to 1930 — the full impact of the industrial sciences on mine labour is evident. Arts, Faculty of History, Department of Graduate

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Williamson, Christian Thoreau. "Hydrologic mechanisms and optimization of in-situ copper leaching case study-BHP Copper, San Manuel, Arizona /." Diss., The University of Arizona, 1998. http://etd.library.arizona.edu/etd/GetFileServlet?file=file:///data1/pdf/etd/azu_e9791_1998_473_sip1_w.pdf&type=application/pdf.

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Mususa, Patience Ntelamo. "There used to be order : Life on the Copperbelt after the privatisation of the Zambia Consolidated Copper Mines." Doctoral thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/9291.

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Includes bibliographical references. The thesis examines what happened to the texture of place and the experience of life on a Zambian Copperbelt town when the state-owned mine, the Zambia Consolidated Copper Mines (ZCCM) was privatized beginning 1997 following the implementation of structural adjustment policies that introduced free market policies and drastically reduced social welfare. The Copperbelt has long been a locus for innovative research on urbanisation in Africa. My study, unusual in the ethnographic corpus in its examination of middle-income decline, directs us to thinking of the Copperbelt not only as an extractive locale for copper whose activities are affected by the market, but also as a place where the residents’ engagement with the reality of losing jobs and struggling to earn a living after the withdrawal of mine welfare is re-texturing simultaneously both the material and social character of the place. It builds on an established anthropological engagement with the region that began with the Manchester school. This had done much to develop a theoretical approach to social change. The dissertation contributes to this literature by reflecting on how landscape and the art of living are interwoven and co-produce possibilities that, owing to both historical contingencies (for example, market fluctuations) and social formation (the kinds of networks and relationships to which one has access, positions in a nascent class structure and access to material means) make certain forms of inhabiting the world (im) possible, (un) successful for oneself and others. Ethnographic fieldwork using qualitative research methods was conducted over a two-year period between 2007 and 2009 with a core of close informant relationships from which a wider network was established. This was complemented by two quantitative neighbourhood surveys to measure the scale of observable phenomena. The author makes a case for an anthropology of "trying", an expression often made in response by Copperbelt residents to how they are getting on. It is one that indicates an improvised life and offers an analytical approach to exploring the back-story to the residents’ observation that in the (ZCCM) past there used to be order.

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Mwamba, Bright. "Water resources management in Zambia: a case of cumulative impacts associated with copper mining in the Upper Kafue Catchment, Copperbelt Province, Zambia." Master's thesis, Faculty of Engineering and the Built Environment, 2021. http://hdl.handle.net/11427/33894.

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Water resources management is high on the agenda both locally and globally because of its important role in social, economic and environmental development. For example, as part of the 2030 Agenda for Sustainable Development, all United Nations Member States adopted 17 Sustainable Development Goals (SDGs) in 2015 that covered thematic issues including water, energy, climate, oceans, urbanization, transport, science and technology. Sustainable Development Goal (SDG) no.6, which targets universal access to safe and affordable drinking water for all by 2030, is of particular interest in this study. The mining industry contributes to socio-economic development; however, it has also contributed to declining water quality in rivers and lakes in many regions globally. In this study, the status and governance of water resources within the Copperbelt province of Zambia over the period 2000 to 2020 was examined. The study investigated population and economic growth within the region and its correlation with changes in water quality and quantity. The research also focused on understanding the ways copper mining is affecting local water resources. The study also investigated challenges faced by regulators and institutions in the water sector, and considered how these challenges could be addressed. Secondary data was obtained from government institutions within Zambia such as National Water Supply and Sanitation Council (NWASCO), Water Resources Management Authority (WARMA) and Zambia Environmental Management Agency (ZEMA), which are the key institutions in the water sector and the environment. Semi-structured interviews were also conducted with the three key institutions in the water and pollution control sectors. The results showed that the total population in the Copperbelt province has increased by 20% since 2000 to a total of 1 972 317 in 2010. The population is projected to be 2 669 635 in 2020, representing about 27% increase from 2010. The rural population is projected to be 423 511 in 2020, representing about 11% increase from 2010 while the urban population will be 2 246 124 in 2020 representing about 29% increase from 2010. The majority of this growth has occurred in urban areas, which grew by about 30% from 2000 to a total of 1 595 456 in 2010. Rural population has increased by 8% since 2000 to a total of 376 861. The results also showed increased economic activities driven mainly by copper mining. Water abstraction has generally declined since 2000 mainly due to decrease in mining activities. In 2000, about 1 million m3 /day was abstracted in the Copperbelt province and about 600 000 m3 per day in 2005. The reduction in 2005 could be attributed to reduction in mining activities and institutional changes in the water sector. Water production and consumption from commercial utilities has generally been in decline from 2000 to 2017. This is also the case with water consumption per capita and water production per capita. For example, water consumption per capita per day in 2001 was 203 liters and reduced to 113 liters in 2017, representing a 44% reduction in consumption. The results showed that water consumption from 2004 to 2008 averaged 100 million m3 while the production averaged 160 million m3 per year. NWASCO attributed the general downward trend in water production and consumption in the province to maintenance and rehabilitation of water infrastructure, and investment in new infrastructure, thereby reducing the unaccounted-for water. The other reason could be that new housing developments prefer to use groundwater sources rather than utility water (supplied by water companies). The reduction could also be attributed to the cost of water and that consumers needed to adjust from the background where utility services such as water supply and sanitation were the sole responsibilities of the mines (ZCCM), prior to privatization. In terms of water supply and sanitation coverage, there has been an increased coverage since 2000. In 2001, the population that had access to water supply and sanitation was 81% and 46%, respectively. Therefore, roughly 50% of the population had no access to sanitation. However, in 2017 the population with access to water supply and sanitation was 91% and 75%, respectively. This represented only 25% of the population in serviced areas that had no access to sanitation. Between 2007 and 2008, the sanitation coverage had seen a reduction compared to the year 2006. This was due to institutional changes on the Copperbelt province, and the 2008 economic recession – the mine townships that were previously serviced by an asset holding after privatization of the mines were taken over by other utility companies. Consequently, the service delivery in the province initially dropped, but then started increasing again in 2009.

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Diaz, Acevedo Nelson Simon. "Exotic deposits derived from porphyry copper systems in Chile." Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1011149.

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The exotic orebodies related to cal-alkaline porphyry copper deposits. are sub-horizontal lenticular bodies of secondary copper minerals that impregnate Tertiary gravels and bedrock of different ages. They lie immediately downslope of the porphyry copper deposits, that is to say. they are related to the propylitic halo of the main deposits, and are considered to have originated with the deposition of copper minerals from solutions that overflowed during the secondary enrichment process. Supergene alteration took place between the late Oligocene and Miocene, by which time both orehodies (exotic and porphyry copper) were established. The paucity of tile denudation since the Miocene in the Andean segment from 21º to 26º latitude S. due to the dominance of a hyperarid climate explains the remarkable preservation of the shallow porphyry copper systems, supergene enriched blankets and associated deposits. This is reflected in the limonites, where the typical boxworks have been partially or totally destroyed on surface by the superleaching. As a result of the lateral migration of the copper-bearing solutions, the exotic deposits show a zonation. alteration and mineralization whose characteristics depend among other factors. on the reactivity of the bedrocks and the Cu/S ratio of the mother deposit. In these deposits three zones can be recognized: Proximal (0 to 2 km Intermediate (2 to 3) and Distal (3 to 8-14 km) with palaeodrainage control. The associations and mineralogical abundance are related to the climate (rain. temperature). In some deposits two important units are detected and they are the Cu-phosphates and Cu-lixiviable (to sulphuric acid) units. The size of tile Chilean exotic deposits varies between 100 and 3.500.000 tons of copper, with a total known resource of 8 M tons of copper. The large exotic deposits are comparable to the resources of a medium-sized porphyry copper- type deposit. The discovery of the exotic deposits is related to the exploration of porphyry copper deposits, where a mass balance of the leached column must be done. Moreover the lithology and alteration of the propylitic halo. permeability, structures, geophysics and geochemistry should be considered. The diorite model is not compatible with a supergene enrichment process, expressed by the absence of colour anomalies, exotic deposits and in the presence of secondary minerals like jarosite, which is coherent with the pyrite deficiency of the system. The projects are for exploitation of reserves by open pit methods. The projects plan to extract and to crush copper oxide ore which will he pre-treated with concentrated sulphuric acid prior to heap leaching, solvent extraction and electrowinning. The copper output varies between 10,000 and 50,000 ton per year of catilode copper. The total investment varies between 20 and 100 millions dollars. For project calculations, estimation of 65 % - 82 % copper recovery and 37 - 40 kg/ton net acid consumption can be used due to the nature of ore. The leaching time is estimated as 30 to 180 days for heaps of 4,5 to 30 metres high. As a result of this, the plant capacity is determined by an annual equivalent of 10,000 to 25,000 ton Cu per year. Pit planning has heen carried out using diverse software on the basis of 5 x 5 x 5 m and 10 x 10 x 10 m block models, evaluated using a kriging package built into the program, giving an overall waste/ore ratio (induding pre-stripping) of 0: I (in an outcrop) to 3: I. The location of the mine and plant sites are associated with the porphyry copper in production, for this the already installed facilities can be used. So there is no need to build a new mine camp or access. The environmental impact is summarized relating to the characterization of the physical, biological and socio-cuitural effects, using the framework of the Base Line study and the Impact evaluation derived from the construction and project operation phases. The conclusions and recommendations will diminish, mitigate and/or eliminate impact derived from the specific activities.

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Hellsten, Mark. "GDP per capita and the privatization of copper mines in Zambia : a time series analysis of unit root with structural breaks." Thesis, Örebro universitet, Handelshögskolan vid Örebro Universitet, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-80704.

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Mudenda, Lee. "Assessment of water pollution arising from copper mining in Zambia: a case study of Munkulungwe stream in Ndola, Copperbelt province." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/27984.

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Water pollution is recognized as one of the major environmental problems in the mining industry. This has been compounded with an increase in agriculture activities. Water pollution is a major problem on copper and coal mines throughout the world and Zambia, the focus of this study, is no exception. Worldwide freshwater resources, which provide important ecosystem services to humans, are under threat from rapid population growth, urbanization, industrialization and abandonment of wastelands. There is an urgent need to monitor and assess these resources. In this context, the physical, chemical and ecological water quality of the Munkulungwe Stream located on the Copperbelt of Zambia, was assessed with possible contamination from Bwana Mkubwa TSF, agriculture activities and subsequent impact on the surrounding community. The chemical and physical parameters were assessed at four sampling locations. Sampling site S1 was located on the Munkulungwe stream upstream of Bwana Mkubwa TSF, S2, S3 and S4 were on the main stream downstream of Bwana Mkubwa TSF. In addition, a macroinvertebrate composition analysis was performed to estimate the quality of water using the biotic index score. Finally, the relationship between physiochemical parameters and biotic index score was analysed to interrogate their inter-relationship with respect to water quality. The results showed that the average values of dissolved oxygen (DO) of 4.52 mg/l, turbidity (40.96 NTU), Co (0.24 mg/l), Pb (0.25 mg/l), Fe (0.36 mg/l) and Mn (0.22 mg/l) downstream exceeded international standards for drinking water. Upstream, the values of Co, Pb, Fe and Mn were within acceptable standards for drinking water, DO and turbidity were above acceptable standards. The metal concentration and total dissolved solutes were impacted by closeness to the mine tailings deposit with the heavy metal concentration being highest at S2 and S3. Moreover, high turbidity levels revealed that land erosion induced by agriculture activities is a severe problem in the area. Physical parameters were high in the rainy season due erosion escalated by rains while chemical parameters were high post rainy season. During the rainy season, the chemical contaminants are diluted and thus they are not such a big impact, but they tend to concentrate up during the dry MDNLEE001 III season. The stream at sampling points S2 and S3 was dominated by species tolerant (leech, Isopod and Snail: Pouch) and semi tolerant (Blackfly larvae and Amphipod or Scud) to pollution. The change in season influenced the composition of macroinvertebrates, with the number of species increased post rainy season. The average biotic index score (2.5) showed that the stream condition is not good, it is slightly polluted. The results showed that water quality downstream was substantially affected by Bwana Mkubwa TSF, agriculture activities and is likely to affect human health and food security. It is recommended that groundwater surrounding tailings dams should be monitored in both active and abandoned mines. Curtain boreholes around a tailings dam can be drilled and the water extracted and treated so that it doesn't contaminate other water bodies. To improve the environmental management of mining related impacts in Zambia, mining areas should be completely rehabilitated. There is need for remediation strategies for abandoned mine sites. Constructed wetlands, roughing filtration and phytoremediation are highly promising techniques, as they are reliable, cheap, effective and sustainable.

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Symington, Sager M. Sheena. "The environmental and social history of the O'Donnell roast yard and townsite near Sudbury, Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ40488.pdf.

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Rojas, Ricardo Vicente 1951. "ORE-WASTE SELECTION UTILIZING GEOSTATISTICS (ARIZONA)." Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291255.

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Sharpe, James Leslie. "Chemical mineralogy of supergene copper deposits of the Cloncurry district, North-West Queensland /." View thesis, 1998. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030822.110153/index.html.

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Matos, José Henrique da Silva Nogueira de 1987. "Evolução metalogenética da mina de cobre de Pedra Verde (CE)." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/287647.

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Orientadores: Ticiano José Saraiva dos Santos, Lena Virgínia Soares Monteiro Dissertação (mestrado) - Universidade Estadual de Campinas, Istituto de Geociências Made available in DSpace on 2018-08-21T19:19:43Z (GMT). No. of bitstreams: 1 Matos_JoseHenriquedaSilvaNogueirade_M.pdf: 14049686 bytes, checksum: 25d55717e4c109fa4bd180699977bb8a (MD5) Previous issue date: 2012 Resumo: A mina de cobre de Pedra Verde situa-se no município de Viçosa do Ceará, NW do Ceará. O depósito é hospedado por rochas supracrustais neoproterozóicas do Grupo Martinópole, Domínio Médio Coreaú. O embasamento é constituído por gnaisses-migmatíticos TTG paleoproterozóico (2,35 Ga). Quartzitos com intercalações de xistos, filitos, metassiltitos e meta-argilitos compõem a sequência supracrustal. ...Observação: O resumo, na íntegra, poderá ser visualizado no texto completo da tese digital Abstract: The Pedra Verde Copper Mine, located at Viçosa do Ceará (CE), contains reserves of 44.932.644 t with 0.9 wt.% of Cu (418.726 tonn of Cu), with silver as by-product. The deposit is hosted by Neoproterozoic supracrustal rocks of the Martinopole Group, in the Médio Coreau Domain. Gneisses-migmatites TTG units compound the Paleoproterozoic basement (2.35 Ga) in the area. ...Note: The complete abstract is available with the full electronic document Mestrado Geologia e Recursos Naturais Mestre em Geociências

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Lemmons, Kelly Kristopher. "Salt Lake City's urban growth and Kennecott Utah Copper a geographical analysis of urban expansion onto a previously proposed Superfund site adjacent to the world's largest copper mine /." Connect to this title, 2008. http://scholarworks.umass.edu/theses/206/.

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22

Reese, Ronald S. "Characterization of organic contamination of groundwater in a mining area, Globe, Arizona." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/277240.

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Organic contamination is associated with inorganic contamination in a plume resulting from acidic mine drainage water in an area of copper mining, Globe, Arizona. The level of dissolved organic carbon (DOC) is low, but is eight times the 0.5 mgC/l background. The source is probably organic reagents used in mineral processing. DOC fractionation using XAD-8 resin sorption chromatography gave a hydrophobic acid fraction (humic substances) of 1.0 mgC/l, and the hydrophobic neutral fraction was also anomalous, being as high as 49% of DOC. The fractionation data matched that for a waste-solution lake, believed to be a source of the aquifer contamination. Loss of DOC is occurring downgradient in the aquifer, based on comparison of DOC/chloride ratios. Loss occurs as the pH increases to over 4 or 5. Sorption onto metal precipitates being formed, particularly of the hydrophilic fraction, may be occurring.

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23

Reinhardt, Katrinka. "Mining and smelting technology and the politics of bronze in Shang and Western Zhou China : an inquiry into the Bronze Age interaction sphere." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=26703.

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In this thesis I focus on mining and smelting in China during the Shang and Western Zhou periods (c. 2200-770 B.C.). The importance of bronze in Shang and Zhou society and the vast quantity of bronze artifacts recovered indicates that the acquisition of metal ore would have been a major occupation of the state. The Shang and Zhou governments controlled their own bronze foundries but did not control the mines. The mines are located in southern China where the Chu state flourished during the Eastern Zhou period, likely due partly to their possession of mineral resources, and in Inner Mongolia where the steppe cultures existed. The Zhou and the Shang were likely obtaining raw materials from southern and northern cultures, either through trade or raid. Provenance studies based on chemical composition of artifact and ore will help resolve the source of Shang and Zhou ore.

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Le, Roux Stephan Gerhard. "Physiochemical controls on the formation and stability of atacamite in the soil surrounding the Spektakel mine, Northern Cape Province, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/79885.

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Thesis (MSc)--Stellenbosch University, 2013. ENGLISH ABSTRACT: The Northern Cape Province of South Africa has played host to numerous mining activities for over a century. To date, most of the mining activity has ceased, leaving the area laden with derelict mine sites and unlined tailings dumps. One such site is the Spektakel mine situated to the west of the town of Springbok. The unlined copper and sulphide rich tailings at the site have the potential to leach elevated concentrations of copper and acidic water into the Buffels River downslope of the site. This poses a threat to the surrounding communities that rely mainly on the river to supply water for drinking, livestock and irrigation. The soil surrounding the tailings dumps was characterised in terms of its mineralogical and chemical properties. The results indicate that the soil contains elevated concentrations of Cu2+, which is bound in the soil in the form of the secondary copper hydroxy mineral atacamite (Cu2(OH)3Cl). No other secondary copper minerals were identified at the site. Analysis of the solution present on the surface of the tailings dumps indicate that the tailings are the main source of the high Cu2+, Mg2+ and SO42- concentrations observed in the surrounding soils. As this solution migrates through the tailings dumps, into the soil, it accumulates Cl- through halite dissolution. The resulting acidic Cu2+, Mg2+, SO42- and Cl- solution reacts with the calcite in the soil, replacing it with atacamite. To determine why only a copper chloride mineral formed in the sulphate rich environment a synthetic solution with the composition of a solution in equilibrium with the soil was evaporated, both in the presence and absence of calcite. The results indicate that when the solution comes into contact with calcite, atacamite immediately precipitated, removing the Cu2+ from the solution. In the absence of calcite Cu2+ remains conservative, accumulating in the solution without precipitating a copper sulphate mineral. This establishes that the elevated Mg2+ concentration of the solution induces the formation MgSO4 aqueous complexes that reduce the activity of free sulphate, thus restricting copper sulphate mineral formation. The results from the soil characterization indicate that the atacamite stabilization mechanisms (circumneutral pH, high Cl- concentration and calcite) in the soil are diminishing. During sporadic rain events the acidic tailings solutions dissolve the calcite and temporarily reduce the Cl- concentration of the soil. To determine how these decreases will influence Cu2+ mobility in the soil, the stability of atacamite was tested by reducing the pH both in the presence and the absence of chloride. The results indicate that an elevated Cl- concentration and a pH > 6 stabilizes atacamite. A decrease in either of these parameters destabilizes atacamite and favours its dissolution. The study concludes that the current chemical conditions in the soil at Spektakel favour the stability of atacamite. However, continued sporadic rain events will reduce the Cl- concentration in the soil by increasing the SO42- concentration. This acidic solution will dissolve the calcite in the soil, thus reducing the buffering capacity of the soil, leading to the instability of atacamite, resulting in the leaching of large quantities of Cu2+ into the surrounding water bodies. AFRIKAANSE OPSOMMING: Die mynbou bedryf was die ekonomiese dryfkrag van die Noord-Kaap Provinsie van Suid-Afrika vir meer as ‘n eeu. Die area was die gasheer vir ‘n verskeidenheid mynbou aktiwiteite tot die mynmaatskappye besluit het om mynproduksie te staak en die gebied te verlaat. Die mynmaatskappye het geen rehabilitasie aan die myne en mynhope verrig nie. Die verlate myne lê verspreid in die area met oop mynhope wat koper en ander swaar metale in die grond, sowel as in die water, na omliggende areas kan versprei. Een van dié verlate myne is die Spektakel myn 40 km wes van Springbok. Die mynhope by Spektakel kan moontlik koper en ander swaar metale in die Buffelsrivier, wat langs die myn verby loop, loog. Dit dien as ‘n bedreiging vir die omliggende gemeenskappe wat staatmaak op die water vir drinkwater en besproeiing. Die grond rondom die mynhope was ge-analiseer om te bepaal hoe erg ‘n bedreiging die mynhope vir die omgewing is. Die resultate dui daarop dat die grond hoë konsentrasies Cu2+ bevat wat vasgebind is in die sekondêre koper mineral atakamiet (Cu2(OH)3Cl). Geen ander sekondêre koper minerale is in die grond geïdentifiseer. Die analise van die oplossing wat bo-op die mynhoop aangetref is dui aan dat dié oplossing suur en gekonsentreerd is t.o.v. Cu2+, Mg2+ en SO42-. Terwyl die oplossing deur die mynhoop migreer los dit haliet in die grond op wat Cl- tot die oplossing byvoeg. Wanneer hierdie suur en Cu2+, Mg2+, SO42- en Cl- ryke oplossing met die kalsiet in die grond reageer word die kalsiet vervang met atakamiet (Garrels en Stine, 1948). Om vas te stel waarom slegs 'n koperchloried mineraal vorm in die sulfaat ryke grond was ‘n oplossing, met ‘n samestelling soortgelyk aan 'n oplossing in ewewig met die grond, verdamp in beide die teenwoordigheid en afwesigheid van kalsiet. Die resultate van die eksperiment dui daarop dat wanneer die oplossing in kontak kom met kalsiet atakamiet onmiddellik neerslaan en Cu2+ uit die oplossing verwyder. In die afwesigheid van kalsiet bly Cu2+ konserwatief in die oplossing; die Cu2+ hoop op in die oplossing en slaan nooit neer nie. Daar is vasgestel dat die verhoogde Mg2+ in die grondoplossing MgSO4 water komplekse vorm wat die aktiwiteit van SO42- verlaag en verhoed dat kopersulfaat minerale kan vorm. Verdere navorsing dui aan dat die chemiese meganismes wat atakamiet in die grond stabiliseer besig is om te kwyn. Gedurende sporadiese reën buie word die kalsiet in die grond opgelos deur die suur mynhoop oplossings wat die pH van die grond verlaag. Die mynhoop oplossing verryk ook die grond t.o.v SO42- wat die Cl- konsentrasie verlaag. Om te bepaal hoe hierdie afname in Cl- konsentrasie en pH die migrasie van Cu2+ beïnvloed was atakamiet oplossbaarheid bepaal. Atakamiet was onderskeidelik geplaas in ‘n suiwer water en chloried oplossing tewyl die pH verlaag was om te bepaal hoe atakamiet oplos in elk van die oplossings. Die resultate dui aan dat 'n verhoogde Cl- konsentrasie en pH > 6 atakamiet stabiliseer. Die afname van beide hierdie veranderlikes het veroorsaak dat atakamiet makliker ontbind en Cu2+ vrystel. Die gevolgtrekking van die studie is dat die huidige chemiese toestande in die grond by Spektakel gunstig is vir die stabiliteit van atakamiet. Met sporadiese reën buie neem die Cl- konsentrasie in die grond af en los kalsiet op. Hierdie afname in pH en Cl- konsentrasie maak atakamiet meer onstabiel wat gevolglik Cu2+ in die grond en water rondom Spektakel vrystel.

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Pestilho, Andre Luiz Silva 1985. "Sistemática de isótopos estáveis aplicada à caracterização da evolução dos paleo-sistemas hidrotermais associados aos depósitos cupríferos Alvo Bacada e Alvo Castanha, Província Mineral do Carajás, PA." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/286851.

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Orientadores: Lena Virginia Soares Monteiro, Roberto Perez Xavier Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências Made available in DSpace on 2018-08-19T17:30:40Z (GMT). No. of bitstreams: 1 Pestilho_AndreLuizSilva_M.pdf: 3902456 bytes, checksum: 1316b1f2f664966b7e4c2d9a46a528d2 (MD5) Previous issue date: 2011 Resumo: Localizados na porção norte da Província Mineral de Carajás, a uma distância de cerca de 8 km do depósito de óxido de ferro-cobre-ouro de Sossego, estão os depósitos de cobre Alvo Bacaba e Alvo Castanha. Esses depósitos encontram-se ao longo de uma zona de cizalhamento regional de cerca de 60 km de extensão, no limite entre o Supergrupo Itacaúnas e seu embasamento representados principalmente pelos migmatitos do complexo Xingu. O Alvo Bacaba é hospedado pelo granito Serra Dourada e pelo tonalito Bacaba, enquanto o Alvo Castanha é Ambos os depósitos exibem amplas zonas de alteração hidrotermal que compreendem quase que respectivamente a albitização, a escapolitização, a formação de óxidos de ferro, a alteração sódico-cálcica, a alteração potássica, a formação de turmalina, a sericitização, a cloritização, a epidotização e a carbonatização, embora estes depósitos mostrem diferenças, como a alteração sódico-cálcica que apesar de ser bem desenvolvida no Alvo Castanha, é quase inexistente no Alvo Bacaba, onde apenas ocorre como alteração nos gabros. Também o Alvo Bacaba possui uma associação de minerais distintas, composta por calcopirita±pirita±bornita, enquanto o Alvo Castanha exibe a associação calcopirita±pirrotita±pirita. Informações sobre evolução paragenética e dados de isótopos estáveis indicam que os depósitos Alvo Bacaba e Alvo Castanha evoluíram durante progressivo resfriamento. Entretanto, esta redução com relação à evolução paragenética foi maior no Alvo Bacaba do que no Alvo Castanha, e a fugacidade de oxigênio foi mantida alta no Alvo Bacaba. A temperatura de deposição do minério estimada para o Alvo Bacaba pode ter ocorrido entre 220 °C e 410 °C, enquanto no Alvo Castanha esta teria ocorrido entre 350 °C e 420 °C. A evolução isotópica do Alvo Bacaba é similar àquela caracterizada para o depósito de Sossego, com uma redução acentuada da temperatura acompanhada por um decréscimo no valor de ?18O e acréscimo no valor de ?D e evidências de misturas de fluido juvenil e de fonte não magmática. Já para o Alvo Castanha, as composições isotópicas dos fluidos hidrotermais indicam a predominância de uma fonte magmática. Estas características e similaridades com aquelas de Sossego podem apontar para uma contribuição de águas magmáticas e oceânicas no sistema hidrotermal que originou todos estes depósitos Abstract: The Alvo Bacaba and Alvo Castanha copper deposits are located at the northern part of the Carajás Mineral Province, at a distant radius of about 8 km from the Sossego iron oxide-copper-gold deposit. These deposits occur along a regional shear zone 60 km wide, in the limit between the Itacaiúnas Supergroup and its basement represented mainly by migmatites of the Xingu Complex. Both deposits exhibits widespread hydrothermal alteration zones comprising albitization, scapolitization, iron oxide formation, sodic-calcic alteration, potassic alteration, tourmaline formation, sericitization, epidotization and carbonatization, although these two deposits show differences like sodic-calcic alteration, which is well developed in Alvo Castanha, but it is almost inexistant in Alvo Bacaba, being present only in its altered gabbros. Also the Alvo Bacaba shows ore minerals association essencialy composed by chalcopyrite±pyrite±bornite while the Alvo Castanha shows the association of chalcopyrite±pyrrhotite±pyrite. Paragenesis and stable isotope data indicate that the Alvo Bacaba and Alvo Castanha deposits have evolved with temperature decrease. However, the temperature drop in relation to the hydrothermal alteration succession was greater in Alvo Bacaba than the Alvo Castanha, and the oxygen fugacity was kept higher at Alvo Bacaba. The estimated temperature for ore deposition in the Alvo Bacaba was between 220 °C and 410 °C, while the Alvo Castanha it would have occurred between 350 °C and 420 °C. The isotopic evolution of the Alvo Bacaba is similar to that characterized for the Sossego deposit, with a steep temperature reduction accompanied by decrease of ?18O and increase of ?D values and fluid mixing evidences. In the Alvo Castanha, isotopic compositions of the hydrothermal fluids indicate predominance of magmatic sources. These characteristics and its similarities with those of the Sossego deposit could point to a contribution of magmatic and ocean waters in the hydrothermal system that originated all deposits Mestrado Geologia e Recursos Naturais Mestre em Geociências

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Salimo, Luckmore. "Gold mineralisation at Masumbi Au-Cu Prospect, west Kenya : implication for gold exploration in the Archaean Ndori Greenstone Belt of Kenya." Thesis, Rhodes University, 2014. http://hdl.handle.net/10962/d1020961.

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The Masumbi Au-Cu deposit in the Ndori Greenstone Belt of western Kenya is hosted in dacitic volcanics of the Nyanzian Group (2710 ± 340 Ma) and dioritic to granodioritic felsic intrusives (2504 ± 48 Ma). The deposit is characterised by gold and copper mineralisation that is associated with quartz-sulphide veins and veinlets. The copper mineralisation typically occurs as chalcopyrite. Gold is closely associated with pyrite in mineralogy and its pathfinder elements silver, bismuth, tellurium and selenium in geochemistry. The gold occurs in two forms that may indicate two generations of precipitation: the equant and the elongate forms. Based on Au/Ag ratios, the equant gold grains can be classified as native gold as their gold content is greater than 90 wt%. The elongate gold grains can be classified as electrums as their silver content is greater than 38 wt%. While there is a strong Au-Ag association within individual gold grains supporting an orogenic model for the gold mineralisation, mineralisation at the Masumbi Prospect appears atypical of Archaean orogenic gold deposits because of the abundance of copper (up to 0.43%). The enrichment of silver, copper, bismuth and tellurium in ore assemblages is common in porphyry, VMS and epithermal systems, but their presence at Masumbi does not preclude the formation as an orogenic deposit. Assay results from three Masumbi diamond drill-holes show an apparent correlation between gold and copper. However, petrography and electron probe microanalyses results from this study indicate that chalcopyrite is an earlier phase than pyrite as it occasionally occurs as inclusions in pyrite. This petrogenetic relationship between pyrite and chalcopyrite suggests that there is no temporal relationship between gold and copper mineralisation. Statistical analysis of the assays shows no linear correlation between gold and copper thereby supporting the above findings. The gold and copper mineralisation have been interpreted as forming as two separate events with copper forming first followed by gold. These events are both related to the intrusion of the felsic rocks that are associated with the Aruan metamorphic event that has been responsible for the bulk of the gold mineralisation on the Tanzanian Craton. The common alteration assemblage in the Masumbi rocks comprises chlorite and epidote. This alteration assemblage is typical of regional greenschist metamorphic facies grading into amphibolite metamorphic facies in the Nyanzian Group of Kenya. However, these alteration minerals could possibly be products of propylitic alteration in the rock groundmass. Other alteration mineral assemblages, possibly of hydrothermal origin, comprise muscovite, sericite, quartz, carbonate, associated with the sulphides pyrite and chalcopyrite. Although the occurrence of gold appears to be controlled by the presence of pyrite, it is also associated with silicification. Exploration methods have been proposed to target undiscovered gold deposits in the Ndori Greenstone Belt that are similar to the Masumbi deposit. These methods could probably be applied to vein-type gold deposits in other granite-greenstone terranes in the Lake Victoria Goldfields.

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Rodrigues, Viviane Drumond 1983. "Avaliação da biodiversidade de bactérias associadas a ambientes de mina." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316917.

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Orientador: Laura Maria Mariscal Ottoboni Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia Made available in DSpace on 2018-08-25T23:22:56Z (GMT). No. of bitstreams: 1 Rodrigues_VivianeDrumond_D.pdf: 5631358 bytes, checksum: 6072655858120e417b92336ddd538828 (MD5) Previous issue date: 2014 Resumo: O conhecimento acerca da diversidade microbiana associada a ambientes de mina é limitado, apesar da importância que alguns micro-organismos podem ter no processo de biolixiviação e biorremediação ambiental. Adicionalmente, micro-organismos que vivem em condições inóspitas, como os diferentes ambientes de mina, vêm despertando interesse cada vez maior por possuírem enzimas de interesse industrial. Neste sendido, a análise da biodiversidade funcional e estrutural de micro-organismos presentes em ambientes de mina é de fundamental importância para entender a estrutura e a complexidade das comunidades microbianas em ambientes extremos. Neste trabalho a diversidade microbiana foi analisada em diversos ambientes da mina de cobre do Sossego, localizada em Canaã dos Carajás, sudeste do Pará por abordagens dependentes e independentes de cultivo. A composição taxonômica associada a ambientes da mina do Sossego: taludes (estruturas geotécnicas) e entorno da drenagem dos depósitos de Sossego (T-SO1, T-SO2, ED-SO1, ED-SO2) e Sequeirinho (T-SE1, T-SE2, ED-SE1, ED-SE2) foi avaliada por pirosequenciamento do gene de rRNA 16S. Os resultados indicaram que a comunidade de bactérias de talude é distinta do entorno da drenagem e o conteúdo de matéria orgânica e maior disponibilidade de água foram os principais fatores para as diferenças. Os principais táxons responsáveis pelas diferenças foram Acidobacteria, Chloroflexi, Gammaproteobacteria e Firmicutes. Por meio de técnicas dependentes de cultivo, 64 bactérias heterotróficas foram isoladas a partir das amostras SO5, SO6, SO7 e SO9. Estes isolados foram identificados e avaliados quanto à capacidade de produção de enzimas (hidrolases, monoxigenases, sulfoxidases e betalactamase) e compostos (sideróforos, biossurfactantes e antimicrobianos). Foram identificadas bactérias afiliadas aos seguintes gêneros: Acidovorax, Acinetobacter, Brevundimonas, Cupriavidus, Curtobacterium, Kocuria, Lysinibacillus, Pseudomonas, Roseomonas, Ralstonia, Stenotrophomonas e Bacillus, sendo o último respresentado por 43 isolados. Com relação à triagem funcional, 95% das bactérias foram capazes de produzir sideróforos, 58% biossurfactantes, 69% betalactamases, 50% antimicrobianos, 53% proteases, 75% esterases, 20% monoxigenases e três isolados (SO5.4, SO5.9 e SO6.2) apresentaram oxidação seletiva para sulfetos orgânicos. A partir de amostras de drenagem (SO5, SO6 e SO7) foram obtidos consórcios de micro-organismos oxidantes de ferro. Estes consórcios foram testados com relação à capacidade de biolixiviação da calcopirita e foram mais eficientes para a dissolução do cobre do que Acidithiobacillus ferrooxidans LR. A identificação dos micro-organismos presentes nos consórcios foi realizada por eletroforese em gel de gradiente desnaturante (DGGE) e as bandas mais evidentes foram classificadas em Bacillus sp., Delftia sp., Phenylobacterium sp. e Methylobacterium sp. A comunidade de bactérias na mina de cobre do Sossego foi diversa e complexa. Estes resultados mostram um inventário da microbiota em diferentes ambientes da mina do Sossego e as enzimas e compostos obtidos destas bactérias poderão ser utilizadas em processos e tecnologias que permitam a recuperação de metais, como a biolixiviação e biorremediação ou em outras aplicações industriais Abstract: The knowledge concerning microbial diversity associated with mine environments is limited, despite the importance that some microorganisms can have on environmental bioremediation and bioleaching process. Additionally, microorganisms that live in inhospitable conditions, such as different mine environments, have attracted growing interest because they could have enzymes with industrial applications. In this way, structural and functional biodiversity analysis in mine environments is an important issue to understand the structure and complexity of the microbial communities in extreme environments. The present work shows a microbial diversity analyses in some cooper mine environments of Sossego Mine localized in Canaã dos Carajás mineral province, Pará state, Brazil. The bacterial taxonomic composition associated with Sossego cooper mine: slopes (geotechnical structures) and surrounding drainage of Sossego and Sequeirinho deposits was evaluated using pyrosequencing of 16S rRNA gene. The results indicated slope bacterial community differs from surrounding drainage and organic matter content and higher water availably were the main factors of these differences. The foremost taxons accountable by those differences were Acidobacteria, Chloroflexi, Gammaproteobacteria and Firmicutes. Sixty four bacteria were isolated using culture-dependent methods from SO5, SO6, SO7 and SO9 samples. These bacteria were identified and evaluated concerning the capability of enzyme production (hydrolase, betalactamase, monooxygenase and sulphoxidases) and compounds (siderophore, biosurfactants and antimicrobials). It was identified bacteria related with the followed genera: Acidovorax, Acinetobacter, Brevundimonas, Cupriavidus, Curtobacterium, Kocuria, Lysinibacillus, Pseudomonas, Roseomonas, Ralstonia, Stenotrophomonas and Bacillus, the last one showed 43 isolates. In relation with functional screening, 95% of bacteria were capable to produce siderophores, 58% to produce biosurfactants, 69% betalactamases, 50% antimicrobials, 53% proteases, 75% sterases, 20% monooxygenases and three strains (SO5.4, SO5.9 and SO6.2) exhibited selective oxidation for organic sulphides. Iron oxidizing microorganism consortia were obtained from drainage samples and were tested according with its ability for bioleaching of chalcopyrite. The consortia obtained from SO5, SO6, and SO7 samples were more efficient than Acidithiobacillus ferrooxidans LR regarding bioleaching of copper from chalcopyrite. The identification of microorganism presented in the consortia was performed using DGGE technique and the more evident bands were classified as Bacillus sp., Delftia sp., Phenylobacterium sp. and Methylobacterium sp. The bacterial community in Sossego cooper mine was diverse and complex. These results showed a microbiota inventory in distinct mine environments and enzymes and compounds obtained from those bacteria could be used in new processes and technologies that allow to recovery metals as bioleaching, bioremediation or others industrial applications Doutorado Genetica de Microorganismos Doutora em Genética e Biologia Molecular

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Tshibanda, Kabumana Dieudonne. "Contribution à la recherche d'un modèle de gestion d'un passif envronnemental issu d'un traitement métallurgique des minerais sulfurés cuivre zinc en République Démocratique du Congo." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209618.

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Ce travail traite d’un problème de pollution liée à la présence de métaux de base dans des passifs environnementaux issus d’un traitement métallurgique des minerais sulfureux cuivre – zinc provenant de la mine de Kipushi en République Démocratique du Congo. L’objectif principal de ce travail a été d’arriver à proposer des scénarios de gestion durable au passif environnemental de la filière présentant les risques environnementaux les plus élevés. Pour cela, on a d’abord procédé à une identification des différents problèmes environnementaux tout au long de la filière de traitement sur les quatre sites d’exploitation. Ensuite on a prélevé des échantillons puis procéder par des tests de disponibilité à la lixiviation à l’eau déminéralisée pour évaluer les fractions solubles des métaux de base présents et aussi par des tests de conformité de mise en décharge afin de classer ces rejets conformément à la directive européenne 2003-33-CE. Ainsi, les rejets Ex – UZK ont été identifiés comme les plus dangereux de la filière au regard de cette directive, car les quantités lixiviées de cuivre et de zinc dans ces rejets ont dépassé largement les limites fournies par la directive, et donc ils ne peuvent même pas être mis en décharge de classe I sans traitement métallurgique préalable pouvant permettre leur dépollution. Par contre, les autres rejets de la filière, en l’occurrence les rejets de flottation de Kipushi et les scories de fusion pour matte de cuivre, peuvent eux être acceptés en décharge de classe I, sans traitement préalable au regard des limites fournies par la même directive. Les procédés de lixiviation acide chaude et de digestion ont été proposés et retenus comme scénarios de gestion durable à appliquer à ces rejets Ex – UZK, car ils se réalisent tous deux en milieu acide sulfurique d’une part et d’autre part leur application et surtout leur faisabilité en République Démocratique du Congo reste possible ;en outre ils aboutissent à des nouveaux rejets contenant le fer sous forme d’hématite, pouvant être stocké aisément et durablement dans la nature, ce qui est conforme au principe du développement durable. Nous avons tenté de modéliser ces deux scénarios en discutant et comparant la circulation des flux de matière dans les deux procédés, d’abord autour de chaque opération métallurgique unitaire, et ensuite sur l’ensemble du procédé. Ainsi nous avons pu chiffrer tous les flux entrant et sortant dans le système étudié, en considérant 1000 kg de rejets Ex –UZK alimentés. Cette quantification nous a permis de comparer les coûts opératoires de ces deux procédés. Les résultats obtenus dans la présente étude sont encourageants et nous ont permis de formuler des recommandations pour les études ultérieures éventuelles dont les résultats pourront l’enrichir davantage, notamment sur les aspects technologiques, économiques et environnementaux, de manière à faciliter les applications sur terrain.This work deals with environmental liabilities consisting of base metals pollution due to metallurgical processing of copper – zinc sulphide ores in Kipushi mine in Democratic Republic of Congo. The main objective of this work was to propose sustainable management scenarios for the most important environmental liabilities from metallurgical sector. For this purpose, liabilities were first identified on four metallurgical plants. Then, leaching tests with deionized water were carried out to assess the soluble fractions of base metals. These effluents were also classified according to the test described in european decision 2003-33-EC, which determines the conformity of waste to landfill. Ex – UZK effluents are the most dangerous from this sector, according to this directive, since the quantities of leached copper and zinc were far beyond the limits :they cannot be sent to class I landfill without prior metallurgical processing. However, other effluents like flotation wast and Lubumbashi slag originating from melting for copper matte, are acceptable without prior treatment. Hot acid leaching and digestion were proposed as sustainable management scenarios for to these Ex – UZK waste because :both can be performed in sulfuric acid and they are feasible in Democratic Republic of Congo. They also lead to an iron – rich waste consisting of hematite that can be stored easily and sustainably in nature, which is consistent with the principle of sustainable development. We have modeled these two scenarios by discussing and comparing the flows in both processes, first for each individual metallurgical unit process, and then for the whole chain of value. So we could assess all the inputs and outputs of the studied system, expressed per ton of Ex – UZK waste. The operating costs of both processes were calculated and compared. The results are encouraging. Recommendations were proposed for further studies, in order to investigate more deeply the technological, economical and environmental aspects, to facilitate the final application. Doctorat en Sciences info:eu-repo/semantics/nonPublished

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Kumwenda, Yewa. "Casualisation of labour in the Zambian mining industry with specific reference to Mopani Copper Mines Plc." Thesis, 2016. http://hdl.handle.net/10539/21811.

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A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, South Africa, in partial fulfilment of the requirements for the award of the of Masters of Arts Degree in Labour and Development, Economic Policy, Globalisation and Labour (Labour Policy and Globalisation). Johannesburg, 2016 Zambia has been implementing economic liberalisation policies at the advice of the IMF and the World Bank, to reverse years of economic decline that began with the commodity crisis of the 1970s. As a strategy for economic growth, these included, the deregulation of foreign investment, removal of currency controls, trade liberalisation, decontrolling prices, cutting food subsidies, reduction of state control in running the economy and privatization of state run companies. The rapid implementation of these measures by the Zambian government has seen a change in employment trends in the mining industry from permanent employment to casualisation of labour.These measures have resulted into negative social and economicconsequences on the lives of the casualised mine workers such as job insecurity, poor health and safety standards, lack of protection and union representation, poor remuneration, lack of pension,and other forms of exploitation. Despite booms and busts in the copper price, employment levels have been drastically dropping especially among the permanent mine workers as a cost cutting measure. The role of the state in the running of the mines which Zambia has depended on since independence has diminished significantly and the state is increasingly succumbing to the dictates of the mining Trans-National Corporations (TNCs).The study which was conducted among casualised/contract rock ore drillers at Mopani Copper Mines Plc reaffirms arguments by previous researchers that economic liberalisation has not achieved the high expectations that Zambians wished for and that there is need for government and trade unions to protect the welfare and working conditions of these casualised mine workers who have become a new set of underclass. Through in-depth interviews, observations and documentary analysis, this research has brought to light the social and economic experiences of casualised/contract rock ore drillers at Mopani Copper Mines Plc and questions whether Zambian mine workers were better off when the mines were being run by the state than is currently the case under TNCs. MT2017

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Musonda, James. "Mine workers social recognition of the environmental costs of mining: a case study of Mopani copper mine and Kankoyo Township, Mufulira-Zambia." Thesis, 2017. https://hdl.handle.net/10539/24474.

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Dissertation submitted to the Faculty of Humanities of the University of the Witwatersrand Department of Sociology/ Global Labour University, in fulfilment of the requirements for the Degree of MA Labour and Development, Labour Policy &Globalization, 2015 This study investigates the environmental costs of copper mining in a mining Township of Kankoyo in Mufulira, Zambia. It investigates the ways in which the mine workers in this community experience, assess and respond to the pervasive environmental degradation caused by mining operations. The study indicates that the people of Kankoyo have an implied understanding (physical experiences e.g. smoke, dust etc.) of the risks in their environment but lack explicit knowledge (long term effects). Second, the working class are now in an awkward position between participating in activism against the company that pollutes their environment and the need to keep their jobs. Third, experiences with a polluted environment have divided the Kankoyo between those who engage in community mobilisation (the unemployed) and those who don’t because they want to protect their jobs (the mine workers). As experiences take a gender dimension, women tend to suffer more due to the gender roles they play. Fourth, given their helplessness, the people of Kankoyo now plead for social services not in social justice terms but as a compensation for the pollution suffered. The core conclusion is that workers understand environmental threats but: (a) they have little awareness of the long-term effects and (b) they tend to minimise them. For these workers their economic security i.e. employment, is primary and they prioritise the immediate over the longer term, thus (c) they have not responded to this issue in an organised way, rather their unions tend to focus on traditional workplace/pay issues. In addition, state and environmental organisations’ responses are inadequate. Consequently, the community is forced to accept the negative environmental impacts on their lives and the environment. Therefore, the study makes the following arguments: (a) Mineral resource led development in Zambia has failed. Instead, it has led to devastating environmental and health impacts on the nearby communities; (b) that the provision of social services and housing to the mine workers, and revenue to the government only served to divert attention from the long term and ongoing environmental degradation that has taken place overtime. The slug dams, the accumulated dust heaps, leach plants and long term environmental degradation on the copperbelt attest to this; (c) that the corporate policy on housing only served the interests of the mining companies by stabilising the workforce without regard for the arising health impacts; and; (d) privatisation has increased the vulnerability of the working class to environmental costs of mining. In the end, from the shattered hopes of a good life ‘modernisation’ emerges in the words of one respondent a ‘development’ of ‘environmental suffering’, as Kankoyo remains a ‘bomb waiting to explode’. XL2018

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Mondoka, Ingwe. "Youth perceptions of the role of copper mining in development on the Zambian copperbelt." Thesis, 2014. http://hdl.handle.net/10413/11106.

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Copper is the mainstay of the Zambian economy. From the inception of mining activities in the 1920s, it has accounted for the majority of the country‟s exports and foreign earnings. However, most people are of the view that its contribution to development programmes is disproportionate, well below their expectations. They attribute the contemporary failure to copper price volatility, international market forces, ownership, government ineptitude and the consequences of neoliberalism. Given the large expense involved in establishing and running copper mines, the country depends heavily on foreign capital. A big proportion of the copper that is mined in Zambia is sold in an unprocessed state denying the country additional revenue. This study assesses both the role of copper mining in the economic history of Zambia and its role in contemporary development as perceived and understood by current university-educated job market entrants on the Zambian Copperbelt, their educators and other commentators with work experience in the sector. Theses (M.Dev.Studies)--University of KwaZulu-Natal, Durban, 2014.

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Galabuzi, Grace-Edward. "Re-locating mineral-dependant communities in the era of globalization, 1979-1999 : a comparative study of the Zambian Copperbelt and Timmins, Ontario /." 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR29493.

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Thesis (Ph.D.)--York University, 2006. Graduate Programme in Typescript. Includes bibliographical references (leaves 513-563). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:NR29493

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Lusambo, Martin. "An integrated model of milling and flotation for the optimal recovery of sulphide ores at the Kansanshi mine." Diss., 2019. http://hdl.handle.net/10500/26692.

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Kansanshi mine sulphide ore circuit did not achieve target flotation recovery in 2016, hence it was deemed necessary to carry out a research aimed at optimizing this circuit. The objective of the research was to optimise the Kansanshi milling and flotation circuit processing a copper sulphide ore. In line with this, samples were obtained around the circuit and processed in the laboratory for moisture content, slurry concentration, particle size distribution, and flotation response. This information was then used to build a computer-based model of the Kansanshi milling and flotation circuit. This was done in MODSIM®, a software package specialising in the design and simulation of mineral processing operations. After careful appraisal, appropriate models were selected for the semi autogenous grinding (SAG) and ball mills, SAG mill discharge screen, hydrocyclones, pebble crusher, and the flotation cells. The calibrated model was then used to simulate the effects of key operating parameters on flotation recovery. Analysis using the attainable region technique revealed that the SAG mill feed-rate should be adjusted from 1719 tph to 2090 tph. This would lead to a better utilisation of the pebble crusher that can process 358 tph of pebbles from the current 198 tph. From the simulation work, it was established that rougher flotation recovery can be improved from the current 80.0 % to 82.3 %. The technoeconomic benefits of the proposition are yet to be investigated. Findings from the research concluded that the milling circuit optimum operating parameter; which generated a final product falling predominantly in the range - 150 +38 μm were SAG and ball mills conditions of ball sizes 200 and 40mm respectively, ball mill ball filling 32% and rotational speed between 75 and 80% for both SAG and ball mills. The optimum hydrocyclone feed slurry concentration was found to be 62% solids. Additionally, the SAG mill discharge screen aperture size of 6 mm was the optimum. It must be noted that slurry concentration did not show any impact on both the SAG and ball mills performance. The SAG mill ball filling did not show any significant improvement on performance. College of Engineering, Science and Technology M. Tech. (Chemical Engineering)

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Sikazwe, Yatuta Mukwende. "Playing the Blame Game: Enforcing and Monitoring Standards in Zambian Mines." Thesis, 2014. http://hdl.handle.net/1828/5722.

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This thesis engages with debates surrounding Chinese FDI in Africa by examining the real or perceived effects of Chinese investment in the Zambian mining industry alongside the narrative that developed within political campaign discourse between 2006 and 2011. It probes the perception that Chinese mines were, or are, the “worst employers” in the industry and finds that, while there are a range of problems and issues in Chinese owned and operated mines, the framing of labour problems in Zambian mines as ‘a Chinese problem’ is both unfair and inaccurate. In doing so, this thesis calls for a theoretical and policy-oriented shift away from singling out Chinese employers as the chief architects of labour problems in the mines to a more holistic analysis of the political economy of investment and of the regulatory framework for mining. Graduate sikazwey@gmail.com

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Krause, David J. "The secret of the Keweenaw native copper and the making of a mining district, 1500-1870 /." 1986. http://books.google.com/books?id=MYXhAAAAMAAJ.

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Kapasa, Mukupa. "Mining windfall taxes in Zambia: utilisation and impact on foreign direct investment." Thesis, 2009. http://hdl.handle.net/11394/3230.

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Bezuidenhout, Johannes Jacobus. "A guide for managing the resource model of the copper block-cave at Palabora Mining Company." Thesis, 2018. https://hdl.handle.net/10539/25961.

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A Project Report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Engineering. Phalaborwa, 24 May 2018 The renowned PMC’s copper open pit operation transitioned from surface copper operations to an underground operation in 2002. An exploration shaft from within the open pit, having an exploration tunnel below the open pit bottom served ideally for downward resource exploration drilling. Palabora Underground Mining Project was a first to cave in very competent lithology rock types which utilised the crinkle cut method at its undercut level. Unfortunately, the inadequate underground exploration drilling limited the resource classification and confidence levels, having inadequate drilling to represent the vast footprint block cave area. Consequently, the head grade and the modelled grade required annual revisions. The head grade and modelled grades diverted from each other more than once, despite all the numerous studies with minor and significant model improvements. The block model refinements included adjustments made to the block sizes, draw column alignments with blocks and additions such as the dolerite dilution representation within blocks. The resource model revision pointed firstly to the grade change between the mill grades and predicted modelled grade, and secondly to the identified geometric change and rectification thereof. Significant technical studies refined the resource model to satisfactory levels of confidence. However, the elusive cave behaviour encouraged more studies and refinements as new information became available over time. The copper open pit’s north wall failure occurred in 2004, and this failure material contributed to significant resource losses. The importance of the many approaches and models which predicted or assumed the possible block cave’s life after the failure characterises the PMC block cave uniquely. Some of the significant studies over time, encapsulated in this project report sketch a realistic timeline of the copper block cave at Palabora Mining Company. The initial resource losses became somewhat redeemed during the 2015 study where some of the copper gains were within the failure’s glacial flow, and not from the likely toppling effect which injected some additional years to the life of mine. MT 2018

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Tembo, Angela Kasambo. "Conceptualising quality in health care as perceived and experienced by households : a case study of privatising Zambia Consolidated Copper Mines, Luanshya Division." Thesis, 2010. http://hdl.handle.net/10539/7658.

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Donabedian’s framework, based on the structure, processes and outcomes is widely used to assess quality in health care studies. This study argued the relevance of Donabedian’s framework in exploring changes of quality in health care as perceived and experienced by households. The study was conducted in three mining townships in Luanshya town. Six focus group discussions composed of 8 – 12 respondents were conducted within the households. In addition, interviews were conducted with the District Director of Health in Luanshya town and the Manager Human Resources at Luanshya Copper Mines Plc. In addition, documents such as newspapers and reports from the Zambia Privatisation Agency were analysed. The study revealed that quality in health care had declined based on thirteen areas of concern. In response, households have adopted coping strategies in their access to health care. Households who incur high costs in their access to health care have reduced access to formal care while those that incur low costs have maintained their access. These findings presented a major limitation in Donabedian’s framework. Whereas the framework focuses only on the micro process of users seeking health, it omits important factors described in the blueprint, which affect access to health care. Based on the findings from households and limitations of Donabedian’s framework a blueprint to conceptualise quality in health care within Zambia was proposed. The blueprint recognises the macro context, which considers the economic and social contexts that affect access to health care and, therefore, influence household’s perceptions of quality. Within the macro context, the economic context, which is privatisation, affected household incomes and the cost of travel. Additionally, the social context reflected by services provided by other health systems, has also affected household utilisation of mine facilities. Both factors have helped form households’ negative perceptions of quality in health care.

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Liang, Grace Ya Chih. "Performance of Support Systems Subjected to Dynamic Loads at Two Underground Nickel Mines." Thesis, 2012. http://hdl.handle.net/1807/32481.

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The consequences of mine seismicity can be mitigated by installing support systems capable of absorbing the energy generated by seismic events. Recent work has focused on the testing of individual support or reinforcement units under laboratory impact loads; this, however, does not render itself to easy extrapolation to field conditions. Hence, this thesis focuses on improving the understanding of the performance of support systems in real-world applications through passive monitoring of past rockburst events. 14 years of rockburst history were collected from Coleman Mine and Copper Cliff Mine, two of Vale’s underground (nickel) operations in Sudbury Ontario. Statistical analysis, principal component analysis (PCA) and partial least square projection (PLS) were utilized to find relation between collected parameters and performance capacity. This thesis discusses the adequacy of various support systems and investigates the validity of perceived support performance as compared to the actual performance based on analyses of field data.

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Mugwagwa, Daniel. "Cut-off grade optimisation for a bimetallic deposit: case study of the Ruashi Mine Copper-Cobalt deposit." Thesis, 2017. http://hdl.handle.net/10539/23514.

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A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, 2017 The research was driven by the need to optimise the Ruashi Mining operation to prevent further high-grading without destroying the value of the mine. Ruashi Mining incurred a five-year stripping backlog caused by the drive to reduce costs. As a result of this, a decline in metal production was imminent in the subsequent years. The study was conducted mainly using SimSched Direct Block Scheduler (SimSched DBS) in comparison with schedules from Datamine Net Present Value Scheduler (NPVS) and MineSched. The scenarios investigated have shown that running a mine based on break-even cut-off grade does not optimise the net present value of an operation as shown through the results of Ruashi Mining. The research also proved that royalty affects the cut-off grade for Ruashi Mining, and cannot be ignored. The proper scheduling of wasting stripping resulting from cut-off grade optimisation has contributed to a timeous exposure of high grade to avert the decline in metal production. All the three scenarios have shown that high grade ore can be availed on time, thus producing a smooth metal output for the life of mine. Cut-off grade optimisation is very crucial for any mining organisation as it is the main driver of value. Ore reserves are important in the determination of a company’s share price. High cut-off grade results in fewer reserves, and vice versa. Since mineral reserves are the source of revenue, therefore, the higher the reserves, the higher the revenue. Low cut-off grade may result in the processing of material that does not give high profit at the beginning of the life of mine. This, therefore, lowers the mining company’s net present value. This makes it imperative to optimise the cut-off grade during the mine life in order to optimise the net present value. During mining operations, there are various stakeholders whose interests must be considered during cut-off grade optimisation because they derive many benefits from the mine. These stakeholders include shareholders, employees, government, the community and non-governmental organisations. Cut-off grade optimisation has shown that there is an opportunity to improve the net present value of Ruashi Mining. SimSched gives a higher net present value (NPV) compared to the current Ruashi life of mine schedule. This indicates that SimSched can be used to improve the NPV for Ruashi by producing an optimised schedule. It is important to note though that there is need for the software to have provisions to take into account the initial stockpile status so that there is a holistic approach to the schedule optimisation. The grade-tonnage curve is steeper closer to zero implying that a small change in cut-off grade has a huge impact on reserves. Based on the results of the study it was clear that optimisation in SimSched DBS results in a steeply declining cut-off grade policy compared to NPVS. In addition, optimisation in SimSched leads to highly accelerated mining rate and massive stockpiling. Royalty is a cost which has to be incorporated in cut-off grade optimisation. The study has shown that the cut-off grade for Ruashi is increased by 19.8%. Ignoring royalty may result in overvaluing of an operation. Environmental considerations favour the optimisation of the use of the mieral resources. Consideration of environmental costs lowered the cut-off grade for Ruashi by 16%. MT 2017

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Thobakgale, Rendani. "Evaluation of the geochemical and mineralogical transformation at an old copper mine tailings dump in Musina, Limpopo Province, South Africa." Diss., 2017. http://hdl.handle.net/11602/931.

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MENVSC Department of Ecology and Resource Management Historically, mining activities have generated vast quantities of abandoned tailings dumps in several regions of South Africa and throughout the world. The management and disposal of huge volumes of tailings dumps has constituted a major challenge to the environment. The current study aims to establish the physicochemical properties and mineralogical characterization of the old copper tailings dump in Musina, to reveal the mobility patterns and attenuation dynamics of potentially toxic or heavy metal species as a function of depth, with a view of assessing their potential environmental impact with respect to surface and ground water systems. This information is crucial in the beneficial utilization of copper tailings in the development of sustainable construction materials as part of reuse approach management system. About twelve tailings samples were collected into polyethylene plastic bags from three established tailings profiles drilled by a hand auger. The collected tailings samples were characterized using standard analytical procedures i.e., X-ray fluorescence (XRF), X-ray diffraction (XRD) and scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS). The transfer of potentially toxic or heavy metal species from tailings to water was evaluated using the standardized batch leaching test (EN 12457) and speciation-equilibrium calculations on the aqueous extracts performed by MINTEQA2. The leachate concentration of cations in the collected tailings samples was determined by inductively coupled mass spectrometry (ICP-MS) and the leachate concentration of anions was determined by ion chromatography (IC). A modified sequential extraction scheme was applied on the selected tailings samples of the drilled tailings profiles to further understand the mode of occurrence, the geochemical partitioning and distribution, real mobility, and environmental bioavailability of potentially toxic or heavy metal species in the tailings and tailings-soil interface. The extracted fractions or phases from sequential scheme were as follows: (F1) water-soluble fraction, (F2) exchangeable fraction, (F3) carbonate fraction, (F4) iron and manganese hydroxide associated fraction, (F5) organic matter and secondary sulphide associated fraction, (F6) primary sulphide bound fraction, and (F7) residual or silicate fraction. The results obtained from the seven steps sequential extraction scheme were validated by the determination vi of percentage recoveries from pseudo-total digestion or total metal content of the original sample. The distribution of major elements and potentially toxic or heavy metal species in different leachate fractions obtained after each step of sequential extraction of the selected tailings samples was determined by inductively coupled plasma mass spectrometry (ICP-MS). The appraised data was used to reveal the impact of atmospheric oxygen and infiltrating rain-water on the chemistry of copper tailings dump by depth profiles. Macroscopic properties revealed that the abandoned Musina copper tailings are fine to medium coarse grained, and range in color from light/dark gray at the upper or shallow depth of the tailings, to dark reddish-brown at the deeper zone where the tailings are mixed with the underlying soil or soil-interface. The drilled respective tailings profiles were uniform and slightly varied in both mineralogical and bulk chemical compositions with tailings depth. Mineralogical analysis showed the following order of mineralogical composition within the respective tailings profiles: quartz> epidote> chlorite> muscovite> calcite> hematite. Chalcopyrite was the only sulphide mineral observed by optical microscopy, although not identified or quantified by XRD and SEM-EDS analysis. The observed discrete chalcopyrite grains were attributed to the primary mined ore (i.e., chalcopyrite, chalcocite and bornite) during past copper mining activities in Musina. The tailings profiles were characterized by a medium alkaline pH (7.97-8.37) that corresponds very well with the tailings leachates or pore-water pH (8.36-8.46). This pH was constant and slightly varied with tailings depth in the respective tailings profiles. The high abundance of alumino-silicate minerals and traces of carbonates as calcite coupled with low sulphide mineral content, suggested a high neutralization capacity of the tailings which was in common agreement with an alkaline nature of the copper tailings dump. The chemical composition of major elements within the respective tailings profiles followed the order: Si>Al>Fe>Ca>Mg>K>Na, and corresponds very well with the mineralogical composition of the tailings, whereby alumino-silicates were the most abundant minerals in the tailings samples. Nevertheless, the solid-phase concentration of metals decreases with increasing tailings depth as Cu>Sr>Zr>Ni>Zn and was incongruent with the mineralogical composition within the respective tailings profiles. The main secondary minerals were calcite and hematite, and their proportion increased with increasing tailings vii depth. In addition, hematite formed coatings on the rims and corners of chlorite as observed from optical microscopy, and retained relatively high amounts of potentially toxic or heavy metals (up to 862 ppm of Cu, up to 36 ppm of Ni, and up to 25 ppm of Zn) at the upper and shallow depth of the respective tailings profiles, where bulk density was high and low porosity. Based on batch leaching tests, the amounts of potentially toxic or heavy metal species released into solution were low (0.27-0.34 μg/L Pb, 0.54-0.72 μg/L Ni, 0.88-1.80 μg/L Zn, and 20.21-47.9 μg/L Cu) and decreases with increasing tailings depth, indicating that, presently, the tailings have a minor impact on heavy metals load transported to the receiving surface and groundwater systems. The low concentration of potentially toxic or heavy metal species in solution is primarily due to their retention by secondary Fe oxide phases (i.e., hematite) and the prevailing medium alkaline pH condition of the tailings leachate or pore-water. The observations are consistent with MINTEQA2 speciation calculations, which predicted the precipitation of secondary phase cuprite (Cu2O) as the main solubility-controlling mineral phase for Cu, Zn, and Ni. Primary factors influencing aqueous chemistry at the site are neutralization and dissolution reactions as a function of pH, precipitation, and sorption into hydrous oxides (hematite and cuprite). Based on sequential extraction results, the leachable concentration of potentially toxic or heavy metal species in the water-soluble, exchangeable and carbonate fractions of the respective tailings profiles was relatively low, except for Cu and Mn. For instance, the leachable concentration of Cu and Mn reached 10.84 mg/kg and 321.7 mg/kg at the tailings-soil interface (3 m) in tailings profile C, respectively. The low concentration of potentially toxic or heavy metal species (Cr, Co, Ni, Zn, Cd, and Pb) in these fractions could be due to the low solubility of minerals bearing these trace elements caused by variations in pore-water pH in the respective tailings profiles. The high concentration of Cu and Mn in these fractions suggests their high mobility and therefore most available for uptake in the environment. Except for Cu>Mn>Cr, the contents of potentially toxic or heavy metal species in the Fe and Mn oxides and organic matter or sulphides bound fractions was low, due to the low viii quantity of these fractions in the tailings, despite their high affinity and sorption capacity for potentially toxic or heavy metal species. Likewise, the residual fraction of the respective tailings profiles contained the highest proportion of potentially toxic or heavy metal species. Although the highest potentially toxic or heavy metal species content was in fractions with limited mobility, care must be taken since any geochemical change or shift in the tailings pH or acidic conditions may cause them to be displaced to more mobile fractions, thereby increasing their mobility and environmental bioavailability. Therefore, physicochemical properties of the tailings including pH and mineralogical composition of the tailings samples were the main substrate controlling the geochemical partitioning and distribution, potential mobility, and environmental bioavailability of potentially toxic or heavy metal species by tailings depth. The knowledge of mobility and eco-toxicological significance of tailings is needed when considering tailings dump disposal or reuse in the environment. The addition of copper tailings at 3 and 28 days successfully improved the compressive strength of cement mortar mixtures incorporating tailings at C5 (5%) and C10 (10%) respectively, although with small margin relative to the control mixture (C0). The maximum strength was 31.15 Mpa attained after 28 curing days, and slightly varied when compared with other compressive strength on copper blended cement mortars mixtures in other countries, used for the development of sustainable construction materials. The chemical composition, physical properties and improved compressive strength on cement mortars mixtures incorporating copper tailings, implies that copper tailings are suitable for the development of sustainable construction materials, thereby ensuring job creation, availability of land for development usage, and the reduction of environmental pollution induced by the abandoned copper tailings dumps.

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Schiller, Jeffrey Christopher. "Structural geology, metamorphism and origin of the Kanmantoo Copper deposit, South Australia / by Jeffrey Christopher Schiller." 2000. http://hdl.handle.net/2440/19902.

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Appendices 5 and 6 are made available in CD-ROM format. Includes copies of articles co-authored by the author during the preparation of this thesis as appendix 7. 14 maps (some folded, some col.); inserted in back pocket. Includes bibliographical references (leaves 242-264). System requirements for accompanying CD-ROM: Macintosh of IBM compatible computer. Other requirements: Adobe Acrobat Reader. [15], 264 leaves : ill. (some col.), maps ; 30 cm. + 1 computer optical disk (4 3/4 in.) Title page, contents and abstract only. The complete thesis in print form is available from the University Library. On the basis of the present study it is concluded that there is no firm evidence that the bulk of the mineralisation is pre-metamorphic, although the possibility has not been excluded. Thesis (Ph.D.)--Adelaide University, Dept. of Geology and Geophysics, 2001

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43

Singo, Ndinannyi Kenneth. "An assessment of heavy metal pollution near an old copper mine dump in Musina, South Africa." Diss., 2013. http://hdl.handle.net/10500/11920.

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Heavy metal pollution in water and soil is a serious concern to human health and the associated environment. Some heavy metals have bio-importance but the bio-toxic effects of many of them in human health are of great concern. Hence, there was a need for proper understanding of the concentration levels of these heavy metals in ground water and soil around the community residing in the vicinity of the defunct mine. Mining has become prominent in this area because of the existence of copper lodes, veins and veinlets. It was therefore necessary to assess these selected metals associated with copper mining as their concentration has a tendency to affect the environment and human health. The objective of this study was to establish the levels of lead (Pb)-zinc (Zn)-copper (Cu)-arsenic (As)-nickel (Ni) metals in ground water and soil associated with an old copper mine in the vicinity of the township and to compare them with the South African and international standards in order to safeguard the health of the community using such water for drinking purpose. Clean sampling plastic bottles were used to collect water from five water boreholes being used at present. Water samples were filtered using membrane filtration set LCW (0.45 μm). The samples were digested sequentially with different procedures for the total metal concentration. Concentrations of four metals commonly associated with Cu mining were examined at five different water boreholes which are used for drinking and industrial purposes. Flame Atomic Absorption Spectrophotometer (Perkin Elmar S/n 000003F6067A, Singapore) was used to analyze metals in water samples at Eskom Ga-Nala Laboratory: pH, electrical conductivity and turbidity were analyzed using an auto titrator meter (AT- 500,Japan), conductivity meter (Cole-parmer® YO-19601-00) and turbidity meter (AL 250TIR, Agua lytic, German) respectively. Soil samples were collected from the selected areas where human health is of a serious concern, and a hand held auger drill was used to recover samples, while shovels were used to prepare the sampling area. The samples were sieved up to 63.0 μm particle size and digested with aqua-regia. Flame Atomic Absorption Spectrophotometer (Model: AA400; Year: 2008; Manufacturer: Perkin Elmer; Germany; Serial no: 201S6101210) was used at the University of Venda Laboratory to analyze soil from the study area for possible heavy metal contamination due to the defunct Cu mine in the area. v The results showed variation of the investigated parameters in water samples as follows: pH, 6.0 to 7.51; EC, 70.0 to 96.40 μS/cm and turbidity, 1.05 to 4.56 NTU. The mean concentration of the metals increased in the followed order: Pb<Cu<As<Ni. Ni is the most abundant in the ground water determined with value of (6.49 μg/g). The observations have confirmed that most ground water contains an appreciable quantity of Ni. The mean value of As in water is (4.20 to 4.84 μg/g), Pb and Cu have (2.13 to 2.58 μg/g) and (1.52 to 2.52 μg/g) respectively. For soil samples, the mean concentration of the metals increased in the following order: Pb<Cu<Zn<As<Ni. Pb ranged from (0.023 to 0.036 μg/g) followed by Cu (0.28 to 0.45 μg/g) then Zn (0.026 to 0.053 μg/g), the mean range of As in soil ranged from (0.054 to 0.086 μg/g). However, some studies show much higher contamination of As from the natural sources and Ni with (0.057 to 0.144 μg/g) lastly. Accumulation of heavy metals in soil is of concern due to their toxic effects on human and animals. The quality of ground water from the five boreholes studied was satisfactory with turbidity (T), electrical conductivity (EC) and heavy metals (HM’s) below the WHO limit. The water therefore may, according to the WHO Standards be safely used as a drinking water. The concern lies on pH which was slightly (0.5) below the standard. There is a serious need to monitor the ground water which is now used for drinking purposes. This study revealed that heavy metal pollution in soil from the abandoned Cu mine in Musina is a threat to the health of the community. Although pollution was between medium and low in the contamination index, it is therefore important for the Musina Municipality or mine owner of Musina (TVL) Development Co Ltd copper mine to advocate possible remedial actions which will safeguard the environment and human health. The tailing at Musina’s old Cu mine have high pH and they lack normal soil stabilization processes, as a result the tailing does not develop a good plant cover. Pollution of the ground water resources is also evident in the study area where there is seepage or ingress of polluted water to the underground aquifers. Small-scale mining in Musina is causing further degradation to the environment but it supports the South African Waste Hierarchy by promoting the reuse and recycling of the tailing and mine dumps for the production of bricks. Mine workers are exposed to the above mentioned toxic heavy metals daily. Medicine will not help stop the poisoning. The only way to stop the metal poisoning is to stop being exposed to the heavy metals. Environmental Sciences M. Sc. (Environmental Management)

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Van, Zwieten Adrianus Josephus Maria. "The petrogenesis of the Koperberg suite in the jubilee mine, Namaqualand." Thesis, 1996. https://hdl.handle.net/10539/26642.

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Thesis submitted for the degree MAGISTER SCIENTIAE to the Faculty of Science, Department of Geology, University of the Witwatersrand, Johannesburg The Koperberg Suite intrusion at Jubilee, Namaqualand varies in composition from anorthosite, through mica diorite to pyroxene leucodiorite and pyroxene diorite. Detailed mapping and petrological studies of these rocks indicate that they were sequentially emplaced into the Concordia Granite country rocks, and that each of the rock types represent discrete magmatic events. The sequence of intrusion is from more acidic to more basic. Whole-rock geochemical analyses indicate that these rocks represent cumulates involving variable proportions of plagioclase, orthopyroxene, mica, quartz, oxides and immiscible sulphides. These cumulate phases intruded into the Concordia Granite at the time of peak of metamorphism and deformation in the Okiep Copper District, i.e, about 1030Ma ago, At the time of intrusion, the country rocks were under going partial melting under high grade (granulite facies) metamorphic conditions. and granitic anatects were present in the crust. Hybridisation of basic magma and granitic melts occurred within the shear zones along which the basic magmas ascended. The En content of orthopyroxene in the Koperberg Suite exceeds the An content of plagioclase. This is atypical of basic intrusions and is a consequence of this mixing. Mixing calculations based on the initial 87Sr/86Srratio (Ru) of the Jubilee samples at 1030Ma, imply high levels of assimilation (as much as 80% assimilation in the case of anorthositic rocks) between a granitic component, similar in composition to the Nababeep Gneiss and a mantle-derived basic magma. Sulphide mineralisation was initiated by the assimilation process, which caused the separation of immiscible sulphides from the hybridised magma. Subsequent oxidation of the original sulphide assemblage produced bornite, chalcopyrite and Ti-poor magnetite. Andrew Chakane 2019

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Matidza, Murendeni. "Green synthesis of geopolymeric materials using Musina Copper Mine Tailings: a case of beneficial management of mine tailings." Diss., 2019. http://hdl.handle.net/11602/1467.

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MENVSC Department of Ecology and Resource Management Mine tailings (MT) have been a global problem due to the environmental impacts the waste generates such as air, soil and water pollution. The detrimental impacts include a global problem such as acid mine drainage (AMD) which has been difficult to cleanup. Several studies have been conducted to find alternative measures in reducing or mitigating impacts such as AMD and air pollution. Several studies have revealed how alumino-silicate mineral waste can be used as raw material to produce construction materials. This study aimed at evaluating the potential of synthesizing a geopolymer material from Musina copper mine tailings. Tailings were characterized for their physicochemical and mineralogical compositions using standard laboratory techniques in order to evaluate suitability in geopolymerization. First section of the results presented physicochemical and mineralogical characterization of the Musina copper tailings together with the bioavailability of the chemical species. It was observed that the tailings are mainly composed of SiO2 and Al2O3 as the major oxides indicating that they are aluminosilicate material. Mineralogical analysis revealed dominance of quartz, epidote and chlorite as the major minerals. The bioavailability assessment showed that largely Cu and Ca are bioavailable and highly soluble in an aqueous solution while Al, Mg, Ni, Co, Cr and Fe have a high proportion in non-labile phase. Second section presented the preliminary results wherein the potential application of Musina copper tailings in geopolymerization was evaluated. The results showed that Musina copper tailings can be used to synthesize a geopolymer material. However, it was recommended that several parameters influencing geopolymerization need to be evaluated. The third section presented the evaluation of optimum parameters that influence the geopolymerization process, which include type of alkali activators, alkali activator concentration, curing temperature, liquid-solid (L/S) ratio and curing regime. It was observed that a mixture of NaOH:Na2SiO3.5H20 at a ratio of 70:30 yields a better geopolymer material. The concentration of 10 M NaOH:Na2SiO3.5H20 at a ratio of 70:30 was observed to be the best that yielded the UCS that is acceptable according to SANS1215 standards. When evaluating curing regime, it was found that the material cured using greenhouse has lower UCS as compared to the material cured using oven. The v effect of temperature showed that the UCS decreases with increasing curing temperature. An admixture of river sand and cement was introduced which resulted in a high UCS of 21.16 MPa when using an admixture of cement. The mineralogical composition of the geopolymer bricks showed formation of secondary minerals such as phlogopite, fluorapatite, diopside and actinolite. Batch leaching conducted on the geopolymer bricks detected high leaching of Na from the bricks. Based on the findings of the study of the raw MT potential to produce geopolymer bricks, it was concluded that the material can be used to produce bricks that are within the SANS 1215 requirements. The study further recommended that the study a focus on using cylindrical moulds, other alkali activators and a mechanical mixer. It was also recommended that the greenhouse be restructured to contain heat within the greenhouse during the evening so as to allow constant temperature within NRF

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46

Mundalamo, Humbulani Rejune. "Investigation of the Geology, Structural Setting and Mineralisation the Copper-Sulphide Deposits in the Messina Area, Limpopo Mobile Belt, South Africa." Thesis, 2019. http://hdl.handle.net/11602/1440.

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PhDENV (Geology) Department of Mining and Environmental Geology The study focused on the geology, structural setting and mineralisation of copper-sulphide deposits in the Musina area, located in the Central Zone of the Limpopo Mobile Belt of South Africa. The Messina copper deposits are located in the eastern part of Limpopo Province near the border with Zimbambwe. The deposits stretch from northeastern to southwestern direction for about 15 km. Previous copper mining in the area took place at Artonvilla, Messina, Harper, Campbell and Lilly copper deposits. The current study, however, focused on two main deposits, Campbell and Artonvilla. The origin, nature and mode of formation of the Cu-sulphide deposits in the Musina area have not been established with certainty. Two principal hypotheses on the origin of the Messina copper sulphide deposits have been proposed, viz; a magmatic-hydrothermal model, and meteoric waters model. Consequently, the mode of formation and mineralisation style of the Messina Cu-sulphide deposits remain contentious. Therefore, the main objective of the study was to investigate the nature and mode of formation of Cu-sulphide deposits in the Musina area. Different research methods have been applied in the current study so as to unpack the contradictory positions on the genesis of the Messina copper deposits. This included fieldwork, remote sensing data acquisition, laboratory work, and data analysis and interpretation. Fieldwork involved soil geochemical survey as well as rock and ore sampling within the study area. A total of 295 soil samples, 33 rock specimens and 21 ore samples were collected for laboratory investigation. Laboratory work consisted of a range of methods that included; geochemical analysis, petrographic and cathodoluminescence microscopy, ore mineralogy and ore microscopy, fluid inclusion geothermometry and isotope geochemistry. The work was done in different laboratories including: Mining and Environmental Geology Laboratory, Unviersity of Venda; Department of Geology Laboratory, University of Johannesburg; MINTEK Laboratory in Johannesburg; Société Générale de Surveillance Laboratory in Johannesburg, South Africa; Department of Applied Geology, Geoscience Institute, Göttingen University, Germany and Department of Geology, University of Georgia, Athens, United States of America. Remote sensing data was acquired from Southern Mapping Company, Johannesburg, South Africa. Interpretation of Remote sensing data was done at the University of Applied Sciences, Oswestfalen-Lippe, Germany. Data analysis and interpretation of laboratory results involved the use of: Desktop ArcGIS 10.4.1 for geochemical data interpretation; ENVI 5.1 and ArcGIS 10.4.1 Softwares for remote sensing data; and Triplot version 4.1.2 software for ternary plot for compositional variation of rocks. Soil geochemical survey revealed geochemical anomalies for Pb, Zn, Cu, As and Ni over the known copper deposits in the area as well as over six other areas that have not been associated with any sulphide mineralisation. Such new anomalous areas have been identified as target areas for future exploration of sulphide ore mineralisation. Petrographic studies of the rocks confirmed the host rocks to be amphibolite-quartz granulite, biotite-garnet-quartz granulite, amphibolite, quartzite, hornblende gneiss, quartzo-feldspathic gneiss, potassium-feldspathic gneiss and cal-silicate gneiss. These rocks were subjected to hydrothermal alteration during ore mineralisation within the area. It was further noted that epidote alteration was quite intensive in ore samples, while in unmineralised rock samples it was less intensive. Remote sensing data interpretation revealed spatial distribution and intensity of epidote alteration within the study area and in places coincided either with the known copper deposits or structural features, thus led to the identification of target areas for future mineral exploration in the Musina area. The current study established that the process of ore mineralisation in the Messina copper deposits took place in two distinct phases: first the formation of garnet, graphite, magnetite and hematite during regional metamorphism of the Limpopo Mobile Belt; and secondly, sulphide ore mineralisation resulting in the formation of copper ore comprising, veined, disseminated and brecciated ores. Sulphide ore mineralisation consisted mainly of pyrite, chalcopyrite, sphalerite, bornite, chalcocite and minor pyrrhotite and galena as well as traces of pentlandite, tennantite, mollybdenite, cobaltite and tetrahedrite. This confirms that the Messina copper deposits had complex sulphide ore mineralisation that is typical of hydrothermal mode of ore mineralisation from a magmatic source. The study further establishes the paragenitic sequence of ore mineralisation, comprising four stages: Stage I (Garnet- graphite – Fe oxides); stage II (Quartz- pyrite); stage III (Pyrite- sphalerite - chalcopyrite); and stage IV (Carbonates). Stage III represented the main stage of sulphide ore mineralisation in the area, while Stage IV comprising calcite, dolomite and ankarite marked the final stage of hydrothermal ore mineralisation. Paragenetic sequence identified three generations of quartz; first generation being associated with garnet, graphite, magnetite and hematite, second generation with pyrite and third generation with pyrite, sphalerite and chalcopyrite. Previous studies, however, indicated that there was only one generation of quartz that formed at the temperature between 210o to 150°C, but the current study established that the entrapment temperature of first generation quartz ranges from 315o to 200°C; second generation quartz from 235o to 135°C and third generation quartz from 240o to 115°C. At the same time, sulphur isotope investigation of chalcopyrite-pyrite pair from Campbell deposit registered a temperature of 359°C. The study therefore concluded that the temperature of ore formation within the Messina copper deposits ranged between 359°C and 115°C. The presence of halite and calcite as daughter minerals within the fluid inclusions was noted and this apparently is indicative of high salinity of fluid inclusions, which is considered as a product of direct exolution of crystalizing magma. Raman spectroscopy revealed the composition of gases in the fluid inclusions to be CH4 and N2 with 80% and 20% composition respectively, however, some inclusions were gas-poor. The presence of gases in the fluid inclusions is an indication that there was boiling at the time of entrapment. A narrow range of 34S values of -0.5 to 0.5‰ obtained in this study further confirms the magmatic source of Sulphur as Sulphur from the host rock was found to have high 𝛿34S value of 8.2‰. A genetic model for copper ore mineralisation within Musina area is proposed. The deposits are of polymetallic vein type that are genetically associated with porphyry copper deposits. According to this model, copper ore bodies were formed from hydrothermal fluids originating from magma and were epigenetic in nature. Geological structures in the area acted as conduits for hydrothermal fluids that resulted in the alteration of the host rocks and mineralisation of copper sulphide ore. Thus, the Messina coper deposits are of magmatic hydrothermal origin although the apparent location of a batholith is still unknown and the study recommends further viii research work on the location of the batholith that is presumed to have been the magmatic source. The study further recommend dating of later rocks as well as orebody s it is essential for understanding the process of ore formation in this area. For further exploration, areas that have undergone “moderate” to “high” degree of epidote alteration and lie in close proximity to geological structures such as faults and thrust folds that could have acted as conduits for hydrothermal fluids and resulted in sulphide ore mineralisation and registered high geochemical anomalies for Pb, Zn, As and Ni should be targeted. In support of further mineral exploration within the study area, the study recommend a detailed geostatistical application for the purpose of delineating homogeneous areas based on the combination of lineaments, interpolated soil geochemical maps and thematic maps. NRF

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47

Ndhlala, Blessing. "Modelling, simulation and optimisation of a crushing plant." Diss., 2017. http://hdl.handle.net/10500/22954.

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African copper PLC’s flagship is the copper producing Mowana mine located 129 km from Francistown in the North-Eastern part of the Republic of Botswana. The processing operation at Mowana is a standard flotation plant designed to produce copper concentrates from oxide, supergene, and sulphide ores. The expected average output of 16.2 tons per hour of copper concentrates has never been attained since plant commissioning. The major bottleneck has been established to be located around the crushing circuit of the Mowana production chain. The major hypotheses of this research are that performance in a crushing plant is adversely influenced by moderate and discrete changes in the process. The ultimate objective is to develop a dynamic process simulator, administered in Simulink/MATLAB® background, for application in the design of a control model utilising two crusher variables and a self-tuning control algorithm. In this research work, a process model describing the dynamic operation of an Osborn 57S gyrasphere cone crusher is investigated. Modelling of the Mowana crushing circuit is carried out by combining the steady-state and dynamic components of the crushing equipment in the Simulink/Matlab® environment. Eccentric speed (ES) and closed-side setting (CSS) are amongst the important inputs to the models. The rest of the inputs (crusher power, crusher cavity level, federate, pulley diameters, liner wear measurement, number of teeth of the pinion and bevel gear) are extracted from the data collected across the Mowana mine crushing circuit. While it has been demonstrated that the crusher CSS is the most influential controllable parameter, it has also been demonstrated that crusher capacity and power can be used effectively to optimise the circuit. The use of crushing power and cavity level control is suitable for the crushing circuit since the crushers are running on a constant ES and the CSS is set and reset manually. The outcome of the study presents an insight into the optimization of the Mowana mine crushing circuit through the design of a self-tuning controller for the cone crusher and for prototyping, parameters of a PID controller were determined in the Simulink/MATLAB® environment. The simulation involved the optimisation of the control model as a function of the cavity level of and the power drawn by the cone crusher. A self-tuning control algorithm at PLC and SCADA level of control was then tested. This formed the simulations and training platform. The outcome of the simulations carried out in this research needs to be validated against the real Mowana crushing process control upgrade. This will then inform the modifications and recommended crusher motor resizing exercise to be implemented. Electrical and Mining Engineering M. Tech. (Engineering: Electrical)

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48

Hillwalker, Wendy E. "Selenium and trace metal accumulation in detrital-benthic food webs of lotic and lentic wetlands, Utah, USA." Thesis, 2004. http://hdl.handle.net/1957/29920.

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Concentrations of selenium (Se), manganese (Mn), zinc (Zn), cadmium (Cd), lead (Pb) and arsenic (As) were measured in the water column, sediment and biota, in conjunction with selected physicochemical data, from representative wetland types at a mining site within Salt Lake County, Utah, USA. The selected field sites included Oolitic Pond (lentic) and Lee Creek (lotic), which are moderately contaminated brackish, alkaline aquatic wetlands managed by a copper mining industry. These fishless wetlands are located in a geographic region that poses risk to migratory shorebird populations from dietary Se. A spatial sampling study demonstrated the extent of variation in total Se concentration within the wetlands. With the exception of the sediment compartment, Se concentration did not differ significantly along the 2-mile length of Lee Creek or within the Pond. The differences in sediment total Se concentrations between the Creek East and West segments characterize lower Lee Creek as having two segments distinguished by unique processes that influence the sediment Se accumulation profiles. Se accumulation trends were observed temporally over 3-years (2000 to 2002) and over two seasons (spring and autumn). Total Se body burden in benthic invertebrates was more clearly associated with sediment/detritus Se concentrations than with surface water concentrations. Three invertebrate groups dominated the aquatic invertebrates assemblage in the lotic and lentic benthos; primary consumers (Chironomidae, Diptera), generalist feeders (Hemiptera) and predators (Odonata). The chironomid larvae accumulated 1.3 to 39 times the trace metal concentrations of the Hemiptera or odonate taxa, independent of trace metal type (essential or non-essential) or wetland occupation. Organism-specific factors, such as habitat selection and preferential feeding habits, were proposed to influence benthic invertebrate accumulation profiles by modifying trace metal exposure. Mixed diets, trophic omnivory and the complexity of wetland biogeochemistry limit the power of stable nitrogen fractionation signatures to define benthic food web relationships. Wetland site-specific processes impacted Se accumulating efficiency, with trace metal concentrations from 4 to 7 times greater within the lentic benthic system than the lotic. The fractionation of the natural abundant stable carbon isotopes revealed the importance of sedimentary and detrital organic carbon as dietary sources for the benthic food web. Sediment organic content was not significantly associated with sediment, or invertebrate, Se accumulation profiles. Ecological risk assessments based on sound understanding of metal chemistry and the interactions between the sediment matrix and benthic organisms are necessary to provide tools for environmental management. Graduation date: 2005

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Dissertations / Theses on the topic 'Copper mines and mining – Zambia'

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