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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The economics of small-scale mining : Zimbabwe

Matunhire, I. January 1986 (has links)
No description available.
2

Nationalisation and the perceived consequences for a gold mine / Ronsard Louis Lazare

Lazare, Ronsard Louis January 2012 (has links)
Discussions and considerations around nationalisation of the mining sector in South became more prevalent from 2009. There are certain implications or consequences related to these discussions, considerations or decisions that should be taken into account. The purpose of this study will be to determine what these consequences may be in a South African context by making inference from historic cases of nationalisation in other countries as well as testing the perceptions of respondents from a gold mine. In order to achieve the purpose of this study the researcher will do an in-depth literature study on the concept, history, consequences and related aspects of nationalisation. The perceived consequences will be tested by doing an empirical study on a sample of a gold mine. An online questionnaire has been distributed to the selected sample. The results have been collected by the researcher and was analysed by the Statistical Consultation Services at the North-West University (Potchefstroom Campus). Conclusions have been drawn from the analysed data and are reflected in the document. The results from the empirical study confirmed in most cases what the literature study has identified. The conclusions and recommendations have been provided by the researcher after taking into account the results of the literature and empirical study. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013
3

Nationalisation and the perceived consequences for a gold mine / Ronsard Louis Lazare

Lazare, Ronsard Louis January 2012 (has links)
Discussions and considerations around nationalisation of the mining sector in South became more prevalent from 2009. There are certain implications or consequences related to these discussions, considerations or decisions that should be taken into account. The purpose of this study will be to determine what these consequences may be in a South African context by making inference from historic cases of nationalisation in other countries as well as testing the perceptions of respondents from a gold mine. In order to achieve the purpose of this study the researcher will do an in-depth literature study on the concept, history, consequences and related aspects of nationalisation. The perceived consequences will be tested by doing an empirical study on a sample of a gold mine. An online questionnaire has been distributed to the selected sample. The results have been collected by the researcher and was analysed by the Statistical Consultation Services at the North-West University (Potchefstroom Campus). Conclusions have been drawn from the analysed data and are reflected in the document. The results from the empirical study confirmed in most cases what the literature study has identified. The conclusions and recommendations have been provided by the researcher after taking into account the results of the literature and empirical study. / Thesis (MBA)--North-West University, Potchefstroom Campus, 2013
4

The geology of Pioneer Gold Mine, Lillooet Mining Division, British Columbia

Stanley, Alan David January 1960 (has links)
Pioneer gold mine is 100 miles north of Vancouver in the Bridge River area of the Lillooet Mining Division, British Columbia. The mine has been worked extensively for more than 30 years and has produced over a million ounces of gold. The gold occurs in ribboned quartz veins which average less than three feet in width and are classified as mesothermal. The gold content of the veins is variable and it occurs, with a small amount of sulphides. Gold values greater than 0.5 oz. Au/Ton are considered economic. The Pioneer mine occurs in a northwesterly trending zone, called the Cadwallader Gold Belt, formed by the Hurley-Noel formation of sedimentary rocks and the Pioneer formation of volcanic rocks. The gold-quartz veins are genetically related to the Bralorne intrusions which occur within the rocks of this zone. There is a repetition of these formations in the Pioneer property, which can be explained by normal movement on a fault. A wide zone of serpentine marks the position of this fault, which is called the Cadwallader Break. This Break is a first order fault and can be related to second order faults formed during the same period of deformation. These second order faults are now occupied by quartz and form the veins which are mined. Planes of liquid inclusions in the quartz of the quartz veins have attitudes similar to those of the megascopic planes of rupture. These planes of inclusions were formed by the annealing of microscopic fractures in the quartz veins. The attitude of these fractures was determined by the same deformation which produced the megascopic fractures, including the 'Cadwallader Break'. The Bralorne intrusion in the mine area is composed of the Bralorne diorite and soda granite which contain albite as their only feldspar. No evidence has been formed to indicate that the intrusion is formed by the process of granitization. Sodic solutions, possibly parts of the final differentiate of the magma which formed the Bralorne intrusion have caused albitization of the intrusion and the Pioneer formation. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
5

Converting an ice storage facility to a chilled water system for energy efficiency on a deep level gold mine / Dirk Cornelius Uys

Uys, Dirk Cornelius January 2015 (has links)
The South African gold mining sector consumes 47% of the mining industry’s electricity. On a deep level gold mine, 20% of the energy is consumed by the refrigeration system. The refrigeration system cools 67 ˚C virgin rock temperatures underground. Underground cooling demand increases significantly with deeper mining activities. Various cooling systems are available for underground cooling. This study focuses on the electricity usage of an ice storage system versus a chilled water system for underground cooling. An energy-savings approach was developed to determine possible power savings on the surface refrigeration system of Mine M. The savings approach involved converting an ice storage system to a chilled water system and varying the water flow through the system. The water flow was varied by installing variable speed drives on the evaporator and condenser water pumps. The feasibility of the energy-efficiency approach was simulated with a verified simulation model. Simulation results indicated the feasibility of converting the thermal ice storage to a chilled water system and implementing the energy-efficiency approach on Mine M. Simulated results indicated a 9% electricity saving when using a chilled water system. Various problems encountered by the mine were also a motivation to convert the thermal ice storage system. Converting an ice storage facility to a chilled water system for energy efficiency on a deep level gold mine Energy management is achieved through the monitoring, controlling and reporting of the implemented savings approach. Converting the glycol plant and recommissioning the chilled water plant gave the mine an additional chiller as backup to sufficiently meet underground demand. An annual summer power saving of 1.5 MW was achieved through the conversion and control strategy. It is concluded that conversion of the thermal ice storage system on Mine M results in an energy- and cost saving. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015
6

Converting an ice storage facility to a chilled water system for energy efficiency on a deep level gold mine / Dirk Cornelius Uys

Uys, Dirk Cornelius January 2015 (has links)
The South African gold mining sector consumes 47% of the mining industry’s electricity. On a deep level gold mine, 20% of the energy is consumed by the refrigeration system. The refrigeration system cools 67 ˚C virgin rock temperatures underground. Underground cooling demand increases significantly with deeper mining activities. Various cooling systems are available for underground cooling. This study focuses on the electricity usage of an ice storage system versus a chilled water system for underground cooling. An energy-savings approach was developed to determine possible power savings on the surface refrigeration system of Mine M. The savings approach involved converting an ice storage system to a chilled water system and varying the water flow through the system. The water flow was varied by installing variable speed drives on the evaporator and condenser water pumps. The feasibility of the energy-efficiency approach was simulated with a verified simulation model. Simulation results indicated the feasibility of converting the thermal ice storage to a chilled water system and implementing the energy-efficiency approach on Mine M. Simulated results indicated a 9% electricity saving when using a chilled water system. Various problems encountered by the mine were also a motivation to convert the thermal ice storage system. Converting an ice storage facility to a chilled water system for energy efficiency on a deep level gold mine Energy management is achieved through the monitoring, controlling and reporting of the implemented savings approach. Converting the glycol plant and recommissioning the chilled water plant gave the mine an additional chiller as backup to sufficiently meet underground demand. An annual summer power saving of 1.5 MW was achieved through the conversion and control strategy. It is concluded that conversion of the thermal ice storage system on Mine M results in an energy- and cost saving. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2015
7

Changes in floristic and functional composition on a complex of gold tailings dams near Carletonville, North West Province, from 1996 to 2014

Maguranyanga, Mike January 2016 (has links)
A research report submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfilment of the requirements for the Degree of Master of Science by Coursework and Research Report. Johannesburg, March 2016. / A vegetation survey was carried out in July 2014 on the substrates of 5 tailings dams by selecting 10 sampling sites which were previously used as sampling plots during the 1996/97 survey of Weiersbye et al. (2006). At each sampling site a 100m transect horizontally across the substrate and covering all levels of the tailings dam from the flat top to the toe paddock was established. Each transect was surveyed for the frequency of the species occurring and these were categorized based on their mode of colonization (natural, intentionally introduced and persisting) while tailings were collected by digging approximately 20cm into the ground for soil sample collection per substrate. The recorded species were then divided using Raunkier’s classification categories into growth forms and a comparison was done between the two surveys (2014 versus 1996/7) to identify the species that were lost, those that were still persisting and the new ones that had colonized over time. A total of 51 species (over 15ha) in 36 genera within 14 families were recorded on the tailings dams, compared to 168 species (over 765ha), 98 genera and 59 families found in the previous study. Families with the most species in 2014 were similar to those of the 1996/97 survey, following the dominance order of Poaceae >Asteraceae >Fabaceae >Anacardiaceae, with the percentage frequency of grasses (Poaceae) noted to have almost doubled over this period. Compared to 6 species common across the substrates in the previous study, the later survey recorded 12 common species (6 of the species occurring on all substrates) but overall both studies found vegetation cover to be high (above 65%) on flat tops and berms with species richness being high on the toe paddock>slopes>tops and berms and substrates susceptible to low nutritional (N,P,K,C) value. Indigenous plant species (54.9%) were dominating the tailing dams and were mostly perennials (82.3%) that were naturally colonizing and persisting (72.5%) on the tailings dams (similar to the 1996/97 survey), while alien (45.1%) plant species comprised annuals/biennials (17.7%) that were intentionally introduced (27.5%) prior to the 1996/97 survey by contractors. The ceased ameliorative initiatives since the first survey are believed to have significantly contributed to a decrease in herbaceous species richness, which formed the majority of the introduced species in the former survey (58.8% compared to 29.4%) as they depended on the supplementary additions of fertilizers and lime. Approximately 117 species, 62 genera and 45 families (including Chenopodiaceae, which was dominant) were lost over the 17 years period, the majority of these were introduced prior to the 1996/97 vegetation survey, while only Ficus sp. was the only new species colonizing apart from the increase noted in alien species (some invasive in nature). The decrease in species richness has encouraged woody and semi-woody (35.3%) and grasses (35.3%) to dominate the slimes reaffirming their potential as temporal and long term rehabilitation species that have developed physiological tolerance to acidic conditions, salinity and heavy metal pollution. In conclusion, this study has identified the species that can be used for phytoremediation to provide long terms solutions for dust, air and water pollution and soil erosion suppression for rehabilitation of these contaminated lands (Appendix 8). The survey also helps to identify species that are able to naturally colonize and persist on the tailings dams without supplements, making them ideal economic species to use for rehabilitation. Results also highlight the negative impacts of the lack of ameliorative supplementations, which in turn affects the floristic composition and structure on these tailings dams over time. Keywords: Aerial cover, Macronutrients, Tailings dams, Species richness, Tailings Storage Facilities (TSFs) and Vegetation survey / LG2017
8

Biogeochemical techniques for environmental monitoring and mineral exploration : a case study at the Temora Gold Mine

Huang, Xiaoyan, n/a January 1998 (has links)
Biogeochemistry has been utilized successfully in Australia as a regional or fellow-up geochemical exploration techniques in the arid terranes of Australia. This Master's study is based on the biogeochemistry approach, which relies on the chemical analysis of plant tissues to obtain information on the geology and geochemistry of the underlying rocks. The project involved the systematic sampling and chemical analysis of plant materials and the supporting soils to establish the suitability of using particular tree species for environmental monitoring and their potential as a sample medium in geochemical exploration in the vicinity of the Temora Gold Mine, NSW, Australia. Working on 168 plant tissues (leaves, twigs and bark) in 54 plants species from 8 families at the three sites of background area, mineralized area and tailings area, and 54 supporting soil samples from three strata of 0-5 cm, 20-30 cm, and 30-40 cm, found that there was a good agreement between soil geochemistry and plant geochemistry on the result of a strong geochemical association between Au and As. The As-Au pattern was suggestive of the presence of the Au-As mineralization. Black cypress pine (Callitris endlicheri) LEAVES show a higher ratio of Asminjn/Aumin in the mineralized area than ASbkg/Aubkg in the background area, up to 7 times. The research finding suggests that the LEAVES of Black cypress pine (Callitris endlicheri) have a potential to be a biogeochemical sample medium as better indicators for Au. Golden wattle (Acacia pycnantha) BARK and Yellow box (E. melliodora) BARK appear to be better indicators for Au but more research is required. The most occurrence of anomalies of As, Au, Sb, Cu and Fe were found in Red box (E. polyanthemos) BARK. Red box (E. polyanthemos) BARK may have the potential to be an Au indicator in the area when Red box (E. polyanthemos) is present. Results on test-tolerant plants show that Eucalyptus species: Red box (E. polyanthemos), Coral gum (E. torquata), and Yellow box (E. melliodora) have a higher rate of uptake trace elements from the tailings soils. Therefore, Eucalyptus family generally adapted to metal-rich soils and can be used as cleaning-up indicators and environmental monitors for the tailings area of metal contaminated soils in the Temora Gold Mine.
9

Exposure of Tanzanian gold mine refinery workers to hydrogen cyanide / K. Linde

Linde, Karlien January 2008 (has links)
Hydrogen cyanide gas (HCN{g)) is formed during the process of extracting gold from ore and may pose a risk to the health of the workers at the gold refinery (Mill/plant), especially the risk of detrimental effects on the central nervous system and the cardiovascular system. The measurement of the personal airborne HCN(g) exposure of a worker using sorbent tubes, provides the concentration of the chemical that the worker breaths in. The measurement of the urinary thiocyanate (SCN~) concentration provides the total HCN exposure experience by the worker through all possible routes of exposure. The study's aim was to determine if the workers were exposed to HCN(g) concentrations that was higher than the occupational exposure limit (OEL) , which would mean that the workers are exposed to excessive and possibly harmful levels of HCN. The monitored workers were divided into three homogenous exposure groups or HEGs, according to the their potential level of exposure. The results were compared between the three HEGs and between three work description groups, namely the Mill/plant workers, SGS laboratory assistants and members of the environmental department. The study found that all the workers were exposed to personal airborne HCN(9) concentrations below the OEL. A statistical significant difference was found the personal airborne exposure experienced by the three HEGs and between the Mill/plant workers and the members of the environmental department. No statistical significant difference was found between the urinary SCN" concentration found in the three HEGs or the between the three work description groups. Confounding factors such as smoking, the consumption of cassava, the exposure to fire smoke and the amount of time worked at the mine did not influence the urinary SCN~ concentration. The implementation of a biological monitoring program would enable the identification of any worker that is exposed to excessive levels of HCN. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2009.
10

Exposure of Tanzanian gold mine refinery workers to hydrogen cyanide / K. Linde

Linde, Karlien January 2008 (has links)
Hydrogen cyanide gas (HCN{g)) is formed during the process of extracting gold from ore and may pose a risk to the health of the workers at the gold refinery (Mill/plant), especially the risk of detrimental effects on the central nervous system and the cardiovascular system. The measurement of the personal airborne HCN(g) exposure of a worker using sorbent tubes, provides the concentration of the chemical that the worker breaths in. The measurement of the urinary thiocyanate (SCN~) concentration provides the total HCN exposure experience by the worker through all possible routes of exposure. The study's aim was to determine if the workers were exposed to HCN(g) concentrations that was higher than the occupational exposure limit (OEL) , which would mean that the workers are exposed to excessive and possibly harmful levels of HCN. The monitored workers were divided into three homogenous exposure groups or HEGs, according to the their potential level of exposure. The results were compared between the three HEGs and between three work description groups, namely the Mill/plant workers, SGS laboratory assistants and members of the environmental department. The study found that all the workers were exposed to personal airborne HCN(9) concentrations below the OEL. A statistical significant difference was found the personal airborne exposure experienced by the three HEGs and between the Mill/plant workers and the members of the environmental department. No statistical significant difference was found between the urinary SCN" concentration found in the three HEGs or the between the three work description groups. Confounding factors such as smoking, the consumption of cassava, the exposure to fire smoke and the amount of time worked at the mine did not influence the urinary SCN~ concentration. The implementation of a biological monitoring program would enable the identification of any worker that is exposed to excessive levels of HCN. / Thesis (M.Sc. (Occupational Hygiene))--North-West University, Potchefstroom Campus, 2009.

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