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Optimization of the coal reserve utilization at Grootegeluk Mine, Waterberg coalfield, with regards to the phosphorus content in coalVan Heerden, Carel Wilhelmus 17 March 2016 (has links)
Submitted to:
School of Mining Engineering, Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, South Africa
September 2015 / Most coal seams in the Waterberg Coalfield contain medium to high levels of phosphorus in coal. Thermal coal, which has a lower value than metallurgical coal, is produced from these coal seams. Metallurgical coal used as feed for char production has especially stringent phosphorous content specifications.
Phosphorous levels vary both laterally and vertically through the coal succession of the Vryheid Formation. If the coal horizons with elevated phosphorus could be identified and selectively removed, significant amounts coal could be saved and utilized as metallurgical coal through the life of the mine. Different mining horizons with regards to their phosphorus content have to be determined to increase the amount of char plant feed coal. Bench definitions and their techno-economic applications are therefore the main purpose of the current investigation.
Bench 11 is currently the only source utilized for char plant feed coal. The char plant is therefore entirely dependent on coal supply from Bench 11. This poses a risk on the continual production of char at Grootegeluk Mine. It was determined that this bench is not suitable for char plant feed coal in certain areas of the resource. A high phosphorus coal horizon was identified in the upper portion of the bench. If this coal is removed separately, the phosphorus content of the coal in the remaining portion of the bench would be suitable for char plant feed coal. This alternative step is dependent on the phosphorus distribution in the resource and may therefore not always be effective. No changes to the other bench definitions could be established that would increase the amount of potential char plant feed coal.
Three further aspects were investigated: The potential to reduce phosphorus in coal by means of coal beneficiation was determined. Results showed that phosphorus levels in coal cannot be lowered sufficiently by means of coal beneficiation. Secondly, the suitability of using different coal analyses to improve the estimation of phosphorus in coal was investigated. Results showed that phosphorus prediction and analyses cannot be enhanced nor replaced by other coal analyses. Lastly, the importance of Zone 1 as a source of low phosphorous coal was investigated. Zone 1 is currently not part of the mine plan, but if mined, it could be used as a source for blending; thereby increasing the amount of char plant feed coal from the reserves. In certain portions of the resource, utilizing Zone 1 may be the only feasible way of securing the continual supply of low phosphorus content coal.
Analytical exploration borehole data of phosphorus in coal is limited in certain areas of the resource. Due to the variability of phosphorus in the coal horizons, more borehole data is required to increase the estimation accuracy of phosphorus in the coal. Based on such data, mining horizons might be changed in future to secure more char plant feed coal.
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The development of binderless, smokeless briquettes from bituminous colliery wasteEngland, Trevor January 1993 (has links)
A project report submitted to the Faculty of Engineering,
University of the Witwatersrand, Johannesburg in partial
fulfilment of the requirements for the degree of Master of
Science in Engineering
Johannesburg, 1993 / Superfines of less than 200 micron are generated when mining coal. They have not been successfully beneficiated in the past and are not acceptable to the consumer.
A processh as been developed whereby the superfines are beneficiated, briquetted without the use of binders and devolatilised to produce a premium smokeless briquette which will attract a premium price in the export market. [Abbreviated abstract. Open document to view full version] / MT2017
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Development and evaluation of a dense media cyclone for the Southern African mineral and coal industriesSingleton, J. D. 25 February 2014 (has links)
Dense media separation (DMS) plays an integral part in coal processing as well as in the upgrade
of low grade ore bodies prior to further processing like flotation and leaching. Various
separating vessels are used in DMS; of which the dense media (DM) cyclone is the most
common. However, the limited materials of construction available for DM cyclones leave the
industry with little choice. In addition, the DM cyclones available moved away from the basic
principles of classification hydrocyclones which is to reduce the turbulence in the feed chamber
in order to achieve improved efficiency. The ceramic tiled DM cyclones available in the market
have ceramic tiles installed perpendicular to each other in the feed chamber, which increase the
turbulence in the feed chamber at the expense of longer equipment life. For that reason, a
research project was initiated to establish the current installed base of DM cyclones in Southern
Africa and to develop and evaluate a DM cyclone with a laminar spiral feed chamber design to
reduce the turbulence when feeding the cyclone, whilst achieving the same or superior wear
properties.
Because Cavex is well proven in hard rock mining and coal classification, it was used as basis for the development of a DM cyclone. Individual moulds were developed and produced in order
to fabricate a Cavex DM cyclone with the exact laminar spiral feed chamber that exists when
moulded out of rubber. Afterwards, the Cavex ceramic tiled (CVXT) cyclone was manufactured,
installed and commissioned. Using the basic operating principles of hydrocyclones, the
predicted results were achieved. The 650CVXT results confirmed that a DM cyclone and a
classification cyclone are inherently the same piece of equipment; it is the selection criteria and
material of construction that differ. There is a definite benefit in focussing on metallurgical
efficiency in conjunction with wear properties, rather than equipment life (wear life) as the only
parameter during equipment fabrication. A simple way to achieve improved performance is to reduce the turbulence in the feed chamber. Further work must include the evaluation of the Cavex CVXT DM cyclone in near gravity coal
circuits and to investigate whether the same lower operating pressures (6D compared to
conventional 9D) will result in improved coal yield, as was illustrated successfully in the
separation of fluorspar by DMS, whilst achieving the desired ash contents. The work must
include detailed studies on the effect of feed pressure vs. yield/recovery, when the turbulence the feed chamber is reduced. Overall energy savings should be quantified by reducing the cyclone feed pressure.
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Analyses of coal extraction and spoil handling techniques in mountainous areasKolli, Shiva Prasad B. January 2001 (has links)
Thesis (M.S.)--West Virginia University, 2001. / Title from document title page. Document formatted into pages; contains x, 64 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 63-64).
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The United Mine Workers and the establishment of coal mine safety regulations /Morton, Charles Anthony. January 1954 (has links)
Thesis (M.A.)--Ohio State University, 1954. / Available online via OhioLINK's ETD Center
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Benefit-cost analysis applied to the slope design of steeply dipping, multiple seam coal depositsWolff, Steven Fred January 1978 (has links)
No description available.
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Surface chemistry of coal flotation systemsKelebek, Sadan. January 1980 (has links)
No description available.
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Microbiology of fly ash-acid mine drainage co-disposal processes.Kuhn, Eloise M. R. January 2005 (has links)
The waste products acid mine drainage formed during coal mining and fly ash from coal burning power generation, pose substantial environmental and economic problems for South Africa. Eskom has developed a remediation system employing alkaline fly ash to neutralize and precipitate heavy metals from toxic acidic acid mine drainage streams. The aim of this study was to assess the microbial diversity in and microbial impact on this remediation system.
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A CAD approach to optimize underground mine design and planningSridhar, Chaluvadi K. January 1986 (has links)
Thesis (M.S.)--Ohio University, June, 1986. / Title from PDF t.p.
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A CAD approach to optimize underground mine design and planningSridhar, Chaluvadi K. January 1986 (has links)
Thesis (M.S.)--Ohio University, June, 1986. / Title from PDF t.p.
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