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Characterisation and beneficiation of coal from the New Vaal Colliery, Sasolburg-Vereeniging Coalfield, South Africa, through the application of automated mineralogy

  • Authors: Pretorius, Donavan Johannes
  • Date: 2015-11-11
  • Subjects: Mineralogy , Coal mines and mining - South Africa , Geochemical prospecting , Analytical geochemistry
  • Type: Thesis
  • Identifier: uj:14548 , http://hdl.handle.net/10210/15079
  • Description: M.Sc. (Geology) , The purpose of this study was to assess the MLA’s ability to characterise (e.g. modal mineralogy, elemental assay, particle size distribution, particle density distribution and mineral associations) a coal product from New Vaal Colliery, with the aim to determine any liberation and beneficiation characteristics. In general the MLA assessment on coal is comparatively new and novel, especially at Spectrum (University of Johannesburg), hence research in this regard is required. For the first time New Vaal coal product was characterised with the MLA 600 FEG SEM. The coal product supplied to Lethabo Power Station for the study’s samples, consisted of Top Seam and Middle Seam coal from New Vaal Colliery which is located in the Cornelia subbasin of the Vereeniging-Sasolburg coalfield, South Africa. The proximate analysis characterised the coal as a high-ash (42.25% air-dried) and low calorific value (13.92 MJ/kg air-dried) product. Chemically SiO2 was the most abundant oxide followed by Al2O3 for the XRF analysis, which was mostly derived from the abundant kaolinite clay mineral (determined by petrography, XRD and MLA analysis). Mineralogically inertinite was the most abundant coal maceral encountered during the petrographic analysis. With geochemical characterisation, chalcophile, siderophile, lithophile and radioactive trace elements were found to be mostly comparable to the global average.
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Die optimale benutting van Suid-Afrikaanse uitskotsteenkool

Die optimale benutting van steenkool met verwysing na grootte by Bosjesspruit Steenkoolmyn

  • Authors: Botha, Dirk Cornelius Petrus
  • Date: 2012-09-04
  • Subjects: Coal - South Africa - Analysis , Coal mines and mining - South Africa , Coal - Sampling - South Africa , Coal - Economic aspects - South Africa
  • Type: Thesis
  • Identifier: uj:3492 , http://hdl.handle.net/10210/6882
  • Description: M.Phil. , The study was undertaken at Bosjesspruit, one of the Sasol Collieries, to investigate aspects that contribute to the degradation of coal. Bosjesspruit is penalised with more than nine million rands per year for fine coal that exceeds the set limits. Compliance to quality is the main reason. The cost is directly deducted from the profit. The quality of coal is of importance for the effectiveness of the gasifying process. A feasibility study has indicated that this study is viable. Various factors in the process were studied to identify the system deviations such as: coal bunkers, section and main conveyor belts, geology, production section activities and coal production equipment. A literature study was done and time was spent to become conversant with the coal transport system. The process is described from where the coal is mined, through the handling action up to where it is fed into the Sasol plant gasifiers. Several coal samples of the identified bottleneck areas were taken and analysed. The four main areas that were studied are: Loading actions at East 700 bunker. Incline shaft transfer chute. The horizontal bunker on surface. The South section conveyor chutes. The free-flow technology was researched and developed for an acceptable chute design. The design is now computerised and in use at Sasol Collieries. The current design and its restrictions are compared with the proposed designs to indicate the improvements. A detailed cost analysis was done to determine the expenditures such as: Penalties for fine coal. The cost of adaptability and redesign. - Forecast cost savings after the redesigns are implemented. - Cost to produce coal as well as the income for Bosjesspruit. An economical evaluation indicates that all the suggested solutions are economically justifiable. The results of the study indicate several suggested solutions to overcome the identified bottlenecks. It is further suggested that results of this study are also implemented at the other Sasol mines as well as the mines that are being developed.
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Overall equipment effectiveness optimisation for a reserves constrained underground coal mine in South Africa

  • Authors: Maimela, Moeketsi
  • Date: 2018
  • Subjects: Coal mines and mining - South Africa , Coal reserves - South Africa , Coal - Geology - South Africa , Mining machinery - Maintenance and repair - Safety measures , Production management
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/393654 , uj:32578
  • Description: Abstract: The aim of the research is to investigate factors that optimize the Overall Equipment Effectiveness (OEE) of an underground Bord and Pillar coal mine that has limited coal reserves and unfavorable geological conditions. OEE is a Total Productive Maintenance (TPM) tool that was first introduced by Nakajima. It is used to identify and quantify losses in a manufacturing system by taking into account the six big production losses and grouping them into 3 efficiency baskets known as downtime losses, speed losses and quality losses. The OEE equation is a function of Availability x Performance Rate x Quality, with the key OEE measure applications being for benchmarking purposes, improving performance of individual equipment and that of pieces of equipment functioning as a single manufacturing line or batch process. The research focusses on OEE improvement of a Bord and Pillar mining operation that consists of 10 Continuous Miner (CM) sections, mining both the higher seam and lower seam coal operations. The equipment-suit functions as a batch process and consists of the CM, Shuttle Cars, Feeder Breaker, Conveyor Belts and Roof Bolter. The equipment-suit in use, has to be adequately allocated for correct mining application in order to ensure optimal mining operation with considerations of constrained reserves and poor geological conditions. Three elements making up the OEE equation (Availability, Performance Rate and Quality), are all under review to establish factors that influence the OEE value in a Bord and Pillar mining operation. Availability is a combination of Equipment Availability (EqA) and Use of Equipment Availability (UEA). The EqA is primarily a function of unplanned engineering and operational downtime events such as electrical/ mechanical downtimes, cable damages, changing picks and sleeves on CM cutter head. UEA is driven by production and consequential delays such as conveyor belt downtimes, excessive number of belt extensions/ section moves and roof support due to geological conditions. The average OEE figures for this Bord and Pillar operation are in the region of 45%. The planned qualities and de-rated productivity rate percentages are high with average figures of 85% and 103% respectively. The results demonstrate that Availability is at an average of 52% and presents an area of opportunity for overall OEE improvement. Geological mining conditions inherently contain mining inefficiencies that lead to a loss of direct operating hours (DOH), which effectively affects the availability component of OEE... , M.Phil. (Engineering Management)
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Geological and mineral economic evaluation and assessment of the Permian Karoo Supergroup coal assets owned by Eyesizwe Coal (Pty) Ltd, a Black empowerment company, South Africa

Managers’ attitudes towards workplace trade unionism at a coal mining company

  • Authors: Mphahlele, Emmanuel
  • Date: 2013-07-18
  • Subjects: Labor unions - South Africa , Industrial relations - South Africa , Coal mines and mining - South Africa
  • Type: Thesis
  • Identifier: uj:7626 , http://hdl.handle.net/10210/8496
  • Description: M.Comm. (Business Management) , Trade unionism and trade unions activities in South Africa’s labour relations system and workplaces has a long history of racial segregation characterised by confrontation and antagonism between the employer (management) and trade unions in the workplaces. However, in the South African contemporary labour relations environment the emphasis is more on creation of constructive and cooperative relations between the employer (management) and trade unions in the workplace. The literature study cites managers’ attitudes towards trade unions as one of the factor that could facilitate genuine interaction and promote productive cooperative management – trade unions relations in the workplace. The objective of this study was to assist in identifying and understating managers’ attitudes towards workplace trade unionism in the workplace utilising a coal mining company as a case study. For the purpose of investigating managers’ attitudes towards trade unionism and trade unions in the workplace, a literature review was conducted and the self-administered questionnaire was utilised as the research instrument to collect the primary data about managers’ attitudes towards trade unionism and trade unions in the workplace. The findings of the study reveal that most of the respondents generally harbour positive attitudes towards trade unionism and trade unions in the workplace. Another significant research finding of the study is the identification and existence of four factors underlying managers’ attitudes towards trade unionism and trade unions in the workplace. The factors identified relates to the awareness and understanding of the concept trade unionism and trade unions in the workplace, operational aspects in terms of perceived destructive and constructive role and function of trade unions in the workplace and lastly, management – trade union cooperation and relationship building in the workplace. Recommendations of the study were presented that will assist in improving and entrenching managers’ positive attitudes towards trade unionism and trade unions in the workplace.
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Leadership capabilities and opportunity realisation in the Fourth Industrial Revolution

  • Authors: Venter, Johannes
  • Date: 2019
  • Subjects: Leadership , Technological innovations - Management , Industrial revolution , Artificial intelligence , Coal mines and mining - South Africa
  • Language: English
  • Type: Masters (Thesis)
  • Identifier: http://hdl.handle.net/10210/446406 , uj:39090
  • Description: M.Com. (Business Management) , Abstract: The study explored the leadership capabilities required to realise opportunities brought by the fourth industrial revolution in the South African coal mining sector. A qualitative research paradigm methodology was used. During the literature review references by other researchers were used to form a basic understanding of the origins of 4IR as well as how 4IR is used to modernise the mining sector, considering the current mining industry economic condition. The governments involvement as well as other industries like manufacturing in Industry 4.0 were also explored. Leadership evolution, risks and challenges through the industrial revolutions were furthermore researched and broaden the study’s knowledge base. A total of ten leadership professionals in the coal mining industry that has expert knowledge and experience with 4IR was interviewed and provided valuable input to the study. The research data transcripts were analysed for themes and subthemes that emerged repeatedly...
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