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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

A detailed mineralogical investigation of the Ventersdorp contact reef at Venterspost and Libanon gold mines, West Rand with special reference to the mode of mineralization of this horizon

Rahden, Herbert Valentin Richard von 17 August 2015 (has links)
No description available.
2

Determination of mode I (Kic)fracture toughness of the brittle rock types encountered in the South African mining environment.

Karparov, K. N. January 1998 (has links)
A Dissertation submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of the Master of Science / Drilled specimens from four types of rocks, namely Quartzite, Norite, Sandstone and Coal encountered in the South African mining environment were tested to determine their fracture toughness coefficients, using International Society for Rock Mechanics (I...) standards. The tests were conducted using a MTS servo-controlled testing machine in displacement control mode. (Abbreviation abstract) / Andrew Chakane 2018
3

The integration of indigenous knowledge systems into the environmental impact assessment process in South Africa: perspectives of local communities in Mapela, Limpopo province.

Moyo, Bekezela 01 February 2013 (has links)
The participation of indigenous communities and use of indigenous knowledge systems (IKS) in environmental governance is provided for in several international and national environmental legislation and policies. In South Africa, the National Environmental Management Act 107 of 1998 (NEMA) in Chapter 1, Principle 4g requires that decisions must take into account the interests, needs and values of all interested and affected parties, and this includes recognising all forms of knowledge, including traditional and ordinary knowledge. This study investigated the Environmental Impact Assessment process (EIA) in mining developments in three rural communities in Limpopo Province, South Africa with regards to the effectiveness of public participation in fostering the incorporation of IKS. The qualitative research design used in this study employed several research methods through the utilisation of 3 villages as a case study. Semi-structured interviews, a focus group discussion and document analysis were used to collect information regarding the public participation process and the integration of IKS into EIAs. This report illustrates that IKS exists in rural communities and some of it is relevant to be incorporated in EIAs. This research study has shown that while expert knowledge dominates the EIA process, there is no indication that this is done deliberately to exclude IKS. This study has also revealed that the public participation process has a number of weaknesses such as in the selection and composition of community stakeholders and communication procedures. Suspicions also developed amongst the villagers of community representatives being bribed by the mine, and infighting started within community committees resulting in some community members losing trust in the committees. The disagreements with regards to the integrity of community committees created divisions and this negatively impacted on the public participation process. However, despite these weaknesses, if capacity building for both EIA experts and rural communities is done, the public participation process has potential as a tool to aid the integration of IKS into EIAs.
4

Software integration for human detection in mining UAV systems.

Motepe, Sibonelo. January 2013 (has links)
Mining is one of the main economic sectors in South Africa. Mining activity contains hazards such collapsing of structures, presence of dangerous gases, accidental explosions and fires. Even though most of these hazards are identified and minimized sometimes accidents occur. These accidents lead to human injuries, direct fatalities and fatalities resulting from delays in victims getting medical attention as a result of delays in search and rescue missions. The rescue missions in underground mines present challenges where rescuers are not sure which locations are victims in, what the area conditions like in the rescue path. A quad rotor unmanned aerial vehicle (UAV) for search and rescue missions is presented. The UAV is controlled from a remote location over Wi-Fi. The communication allows data relay to the ground control station. The communication system is tested on the university’s Wi-Fi network. The UAV also contains a vision system that contains a human detection algorithm to give an indication of human presence to rescuers. The human detection system is based on Haar- Cascade classifiers. The model developed was found to have a false alarm rate of 5×10-3% after training. The model was further tested on streaming data and the overall average positive human detection was found to be 97 %. In the same tests overall false average detection was found to be 2.5 %. The video feed is streamed from the UAV to the ground station (GS) and the flight control instructions are sent to the UAV from the GS via Wi-Fi. / Thesis (M.Sc.Eng)-University of KwaZulu-Natal, Durban, 2013.
5

A legal analysis of the application of the broad-based black economic empowerment in the mining sector in South Africa

Ralethe, Mojalefa Patrick January 2022 (has links)
Thesis (LLM. (Development and Management Law)) -- University of Limpopo, 2022 / The study looks into the phenomenon of Black Economic Empowerment in South Africa (B-BBEE) in the mining sector. The newly elected government in South Africa had to deal with the injustices of the past under the apartheid government and had to introduce programmes to help the Historically Disadvantaged South Africans and building the economy. For many years, the mining sector contributed to the South African economy; however, mining operations in South Africa have not given the Historically Disadvantaged South Africans opportunities to participate in the mining industries or partake in the mining sector. The introduction of the Broad-Based Black Economic Empowerment in South Africa aims to promote and provide better opportunities to the previously disadvantaged communities in South Africa. However, it has been reflected that there is a slow transformation in the mining industry and economic participation of the Historically Disadvantaged South Africans in South Africa. The study finds that broad-based black economic empowerment (B-BBEE) policies have had little developmental impact and were not properly implemented in the mining sector. Keywords: Broad-Based Black Economic Empowerment, Affirmative Action, Empowerment and the Mining Sector in South Africa
6

Geochemical and mineralogical characterization of gold mine tailings for the potential of acid mine drainage in the Sabie - Pilgrims's Rest Goldfields

Lusunzi, Rudzani 21 September 2018 (has links)
MESMEG / Department of Mining and Environmental Geology / This study entails geochemical and mineralogical characterization of gold tailings of Nestor Mine and Glynn’s Lydenberg Mine of the Sabie-Pilgrim’s Rest goldfields. A total of 35 samples were collected and were analysed for chemical composition (XRF and ICP-MS), mineralogical composition (XRD). In addition, acid-base accounting (ABA) techniques had been conducted to predict the potential for acid mine drainage. Seepage from Nestor tailings dump and water samples from the adjacent Sabie River were also collected and analysed by means of inductively coupled plasma mass spectrometry (ICP-MS) and immediate constituent (IC) -analytical techniques. The study revealed that Sabie-pilgrim’s rest goldfield is characterized by both acid generating and non-acid producing tailings, and this is attributed to variations in the mineralogy of source rocks. Gold occurred within the Black Reef Quartzite Formation in the Nestor Mine and within the Malmani Dolomite in the case of Glynn’s Lydenburg Mine. Mineralogy and bulk geochemical analyses performed in this study showed a clear variation in the chemistry of Nestor Mine and Glynn’s Lydenburg Mine tailings. Predominant oxides in Nestor mine tailings samples are SiO2 (ranging from 66.7-91.25 wt. %; followed by Fe2O3 and Al2O3 (in range of 0.82-15.63 wt. %; 3.21-12.50 wt. % respectively); TiO2 (0.18-10.18 wt. %) and CaO (0.005-3.2 wt. %). Also occurring in small amounts is CaO (0.005-3.2 wt. %), K2O (0.51-2.27 wt. %), MgO (0.005-1.46 wt. %), P2O5 (0.029-0.248), Cr2O3 (0.013-0.042 wt. %) and Na2O (0.005-0.05 wt. %). The samples also contain significant concentrations of As (137-1599 ppm), Cu (34-571 ppm), Cr (43-273 ppm), Pb (12-276 ppm), Ni (16-157 ppm), V (29-255 ppm), and Zn 7-485 ppm). In the Glynn’s Lydenburg Mine tailings SiO2 is also the most dominant oxide ranging between 47.95 and 65.89 w%; followed by Al2O3 (4.31 to 16.19 wt. %), Fe2O3 (8.48 to 11.70 wt %), CaO (2.18 to 7.10 wt. %), MgO (2.74 to 4.7 wt. %). Occurring in small amounts is K2O (1.12-1.70 wt. %), MnO (0.089-0.175 wt. %), P2O5 (0.058-0.144 wt. %) and Cr2O3 (0.015-0.027 wt. %). Arsenic (As), is also occurring in significant amounts (807-2502 ppm), followed by Cr (117-238 ppm), Cu (10-104 ppm), V (56-235 ppm), Ni (45-132 ppm), Pb (13-63 ppm) and Zn (90-240 ppm). Nestor Mine tailings associated with Black Reef Formation mineralization have net neutralizing potential (NPR) <2, hence more likely to generate acid; and their acid potential (AP) ranges 1.56 to 140.31 CaCO3/ton and neutralizing potential (NP) range from -57.75 to -0.3 CaCO3/ton. Glynn’s Lydenburg Mine tailings dump which is vi associated with dolomite mineralization, however, was not leaching acid. Based on acid-base accounting results, these tailings have more neutralizing potential (ranging between 57.6 and 207.88 CaCO3/ton) than acid potential (ranging between 7.5 and 72.1 CaCO3/ton); and their NPR>2, hence unlikely to produce acid. This is confirmed by paste pH which was in the ranges between 7.35 and 8.17. Tailings eroded from Nestor Mine tailings dump were also found to be characterized by high content of metals and oxides, namely, As, Cu, Ni, Pb, V, and Zn with SiO2, Fe2O3 and TiO2. The tailings were observed eroded into the Sabie River where AMD related precipitate (yellow boy) was also observed, indicating further oxidation downstream. Field observations, onsite analyses of water samples and laboratory results revealed that Nestor Mine tailings storage facility discharges acid mine drainage with considerable amounts of Al, As, Cu, Fe, Mn, Zn and SO4 and very low pH exceeding the limit as per South African water quality standards. High concentrations of these metals have toxicity potential on plants, animals and humans. Upon exposure to oxygen and water, tailings from Nestor Mine are more likely to generate acid mine drainage that can cause detrimental effect to the environment and the surrounding communities. Potential pollutants are Fe, Mn, Al, As, Cr, Cu, Ni and Pb. Tailings from Glynn’s Lydenberg showed no potential for acid mine drainage formation. / NRF
7

Development of product quality management guidelines for informal small-scale brick manufacturing enterprises in Dididi, Limpopo Province, South Africa

Matsiketa, Khensani Eullen 18 May 2018 (has links)
MESMEG / Department of Mining and Environmental Geology / Although clay brick manufacturing has been going on for many years in South Africa, informal small-scale clay brick manufacturing enterprises are not officially regulated. Consequently, informal brick makers in the study area do not adhere to the demanding requirements of the South African National Standards for burnt clay masonry. Therefore, their clay bricks lack uniformity in terms of quality. Preliminary work revealed that over time, buildings constructed with these bricks develop cracks, thereby compromising safety. The importance of product quality management is not well understood in the informal brick manufacturing enterprises. As a result, they do not have any product quality management guidelines. The main purpose of this research was to develop the product quality management guidelines for ensuring quality in small-scale brick making enterprises in Dididi area. The specific objectives were to characterize the raw materials for clay brick manufacturing, identify and assess the technical problems of clay brick production, analyse the process of clay brick production and determine areas where product quality improvement is warranted. The research involved fieldwork which included soil sampling, analysis of clay brick production through the use of questionnaires and onsite observation of the production process, collection of samples of burnt bricks which were examined for compressive strength, water absorption as well as dimension measurements. These were then compared with the prescribed quality standards. Laboratory analyses of samples of raw materials were conducted and these included sieve analysis which was conducted in order to establish the particle size distribution of the raw materials; Atterberg limit tests were conducted in order to establish the physical characteristics of the soil. Chemical and mineralogical analyses were carried out to determine the chemical and mineralogical composition of the soil using XRF and XRD respectively. The textural characterisation of the material revealed abundance of sand sized particles and significantly low amounts of clay and silt. The plasticity of the soil used for bricks manufacturing in the study area was found to be ranging from slight to medium plasticity. Chemical analysis showed elevated silica contents with minor amounts of alumina and iron oxide. XRD analysis revealed the dominance of non-clay minerals with the highest concentration of quartz. The average compressive strengths of the tested brick samples for site A was 3.8, and 2.9 and 3.8 MPa for sites B and C respectively. The water absorption of the bricks was 13.5, 15.0 and 16.1% for samples from Site A, B and C respectively. The bricks dimensions met the recommended standards although their sizes were not uniform. v The survey conducted on brick manufacturing process revealed that the technical inefficiencies were mostly influenced by human and mechanical factors as well as the material inappropriateness. The production process was found to be too manual and labour intensive. Selection of the raw materials for brick manufacturing was based on indigenous knowledge and experience and most of the brick manufacturers lacked the prerequisite experience for making quality bricks. On the basis of the results of this research, it can be concluded that the materials used for manufacturing of clay bricks in Dididi are not well suited for making good quality bricks due to the reduced plasticity of the soil and the high concentration of quartz. These render the bricks brittle. It was also concluded that the production process also contributes to the poor quality of the bricks as the nature of the process was too manual. Selection of materials based merely on knowledge and experience and no scientific tests resulted in selection of inadequate materials which in turn affect the quality of the final bricks. It is therefore recommended that plastic clays be added to the raw clay materials to enhance its moulding property. In addition, materials such as internal fuels and anti-shrinkage materials should be incorporated into the process cycle to prevent cracking during drying and firing. Based on the findings of the analysis of the production process, it is recommended that mechanized techniques be employed in the operation and awareness training conducted to improve the understanding and skills of the brick manufacturers and to ensure production of good quality bricks. / NRF

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