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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.
271

The social effects of resource decisions : a modeling approach

Oswald, Eric B. January 1976 (has links)
Coal-fueled energy development in the Southwest has resulted in a controversy over claims of environmental damage and spiritual and social disruption to the Native American inhabitants of the region. Development has been supported through estimates of the economic benefits that will accrue to the Hopi and Navajo through the planned development. This research has developed a modeling approach to systematically and rationally assess the impacts of energy development on the Hopi and Navajo Tribes. The model incorporates a simulation technique that describes the Indian social systems over time with and without energy development. The variations within the system without energy development and with various levels of development allow insights into impacts. Computer control allows the model to consider many different decisions relative to energy development, and incorporated graphics allow for efficient and fast impact interpretation. The results of the model indicate that proposed impacts on the Native Americans have been exaggerated. Neither the economic impacts nor spiritual disruptions claimed are seen to occur. The model is seen to be a valuable tool for systematic analysis and the presentation of social impact information.
272

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

04 September 2012 (has links)
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.
273

Estimation of the propensity of remnant underground coal pillars to spontaneously combust during opencast mining at a colliery in the Witbank coalfield

Gemmell, Graham Barry January 2017 (has links)
A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering, 2016 / Spontaneous combustion of coal may occur when coal is mined, stored or transported and is influenced by a combination of intrinsic and /or extrinsic factors. While it is unusual for intact seams to burn in the highwall, the most common occurrence is when surface mines extract seams previously partially mined by underground bord and pillar operations. The aim of the study is to provide a predictive model (matrix) of the spontaneous combustion potential of remnant pillars at Colliery X. A number of different thermal, chemical and petrographic tests (coal factors) will be undertaken to determine their individual and collective impacts on the sponcom predictive model. The primary geology at the mine is conformable with that of the Witbank Coalfield. Battacharyya (1982) described 3 main factors in the spontaneous combustion of coal, mining factor, coal factor and geological factor which have an aggregate effect. Some of the main historical and present theories of sponcom are the pyrite theory, the bacterial theory, the oxidation theory and the humidity theory. It is important to note that no single factor is responsible for spontaneous combustion. The oxidation of coal occurs constantly. The temperature of the coal is a function of the rate of heat generation versus the rate of heat loss. Fires can start at outcrops and move through interconnected workings with heat transfer by conduction (into the overburden) or convection (between panels).The overburden can also insulate the burning coal seam. Geological factors such as depth of overburden, the degree of fracturing, and the nature of the overlying strata vary between coalfields. A coal seam fire or mine fire is the underground smouldering of a coal deposit, often in a coal mine. Such fires have economic, social and ecological impacts In order to extinguish a fire, one of three elements, fuel, oxygen, or energy, must be removed. The components of the fire triangle can be further subdivided into conventional mine control techniques and more or less unconventional or unproven mine fire control techniques. The thermal techniques discussed include the crossing point temperature, thermogravimetric analyses and oxygen absorption. Macerals, the microscopically identifiable organic constituents of coal, are one of the three basic parameters that define coal. The other two parameters are the coal rank and the mineral matter Vitrinite is the principal maceral group of the No.5 seam and inertinite dominates the No.2 and No.4 seams. The results obtained from the 22 drill-core samples and 2 ROM samples were matched to the existing borehole dataset (2296 boreholes) based on similarity of heat value (figure 3.11). A total of 24 test results (thermal, chemical and petrographic) from borehole A and borehole B were thus assigned to the borehole database which has approximately 1500 samples for each seam. By linking the laboratory datasets (borehole A and B) and the existing borehole database used for resource modelling, the sponcom variables could be modelled in a similar way to the coal resources. The overall risk matrix was calculated on a full seam basis by combining 15 variable scores, each variable having a score of 0, 1 or 2 (low-mod-high probability). The overall results from this research produced clear and unambiguous contour plans of different factors effecting sponcom of coal using single variable and combined variable datasets. In conclusion, it appears that the acceptability of a method for determining spontaneous heating characteristics of coal mainly depends upon how closely it predicts the spontaneous heating behaviour in the field conditions / CK2018
274

Mining for development? : a socio-ecological study on the Witbank coalfield.

Filitz, John Karl. January 2011 (has links)
Coal mining on the Highveld has historically served, and continues to serve as an indissoluble cog in South Africa’s development. The study contends that the inherent speculative character of coal as a finite resource results in bearing costs beyond the financial sphere. These costs at some stage of the mine life-cycle have to be accounted for. By using a Polanyian interpretation of double movement and crisis, the study argues that the manner in which natural factors such as coal have historically been inscribed in the production process, alongside labour and technology, to a large degree determine the character of productive relations in a particular society. More fundamentally, it is argued, this interaction between capital, society and nature determines the extent to which the State is able to perform its role of counter-movement against the over-exploitation of society and nature. This is demonstrated by situating the development of a former coal mining village, Rietspruit colliery, within the necessary historical phase of South African development – as hinged upon the accessibility and availability of coal, in particular from the Witbank coalfield. It is however, in a post-coal mining context that the study alludes to the unintended social costs arising from coal-led development, arguing social costs and inequality as evident at Rietspruit colliery, as effectively institutionalised. This is due to the historic function of the State vis-à-vis facilitating mineral extraction. On this basis, the study calls into question recent sustainable development discourse such as the Department of Minerals and Energy’s Sustainable Development through Mining (2009) (SDM) initiative. The study argues the notion of mineral extraction and coal mining in particular, serving as the means de jour for achieving sustainable development, as flawed. This is illustrated at Rietspruit colliery by reflecting upon the manner in which a post-mining sustainability plan was implemented. The core issue concerns the dis-embedding of social costs related to mining, including mine closure, from the necessary historical, socio-political and socio-ecological context. Compounded by a poorly enforced regulatory environment, this approach views mine closure, including the social aspects of mine closure, in a de-politicised, technocratic manner of rationalising closure as cost-effectively as possible. It is here that the utility of the socio-ecological approach is made evident, by opening up the discursive space for social justice discourses relating to the social costs of coal mining, to find common ground with discourses concerned with environmental activism. / Thesis (M.Dev.Studies)-University of KwaZulu-Natal, Durban, 2011.
275

The social and political development of a new coalfield : the Dukeries 1913-51

Waller, Robert January 1981 (has links)
The thesis describes the social and political effects of the transformation of the Dukeries district of Nottinghamshire, where seven new coal mines were sunk between 1918 and 1928. The coal companies responsible for developing the Dukeries field constructed new colliery villages 'at the pit gates' as part of their investment. The thesis deals with the history and characteristics of these townships, planned, built and owned by a single authority. Like other new communities, they suffered 'teething troubles'. It proved difficult to engender a unified community spirit as miners and their families migrated from older coalfields throughout Britain during the early years of high labour turnover. Relationships were strained between the miners and the existing residents of the Dukeries, although the aristocrats whose landed estates gave the district its name came reluctantly to favour mining because of the royalties they obtained therefrom. The first years of the new coinmuniti j:.es were beset by difficulties affecting the provision of facilities for education, religion, shopping, female employment and leisure. But the thesis does not just analyse the problems accompanying industrialisation. The power of the employers in the communities they had created produced much characteristic of company towns. Political representation and control was retained by the colliery companies and the old leaders of Dukeries society, while the Labour Party was not founded until the 194Os. The 'non-political' Spencer Union, a Nottinghamshire phenomenon, monopolised trade unionism in the new pits. Minor regulations were enforced in the villages by uniformed company policemen. As 'benevolent paternalists', the companies sponsored stores, sport, recreation and even religion. The notion of the orderly 'model' village was encouraged as a means of disciplining the workforce. The predominant characteristics of the colliery villages did not disappear until the 194Os, when the war followed by nationalisation destroyed the power of the private owners.
276

Caught between a risk and a hard place making senese [sic] of a chronic technilogical [sic] disaster in Rock Springs, Wyoming /

Coburn, Michael S. January 2009 (has links)
Thesis (M.A.)--University of Wyoming, 2009. / Title from PDF title page (viewed on Apr. 12, 2010). Includes bibliographical references (p. 94-98).
277

Matewan before the massacre : politics, coal, and the roots of conflict in a West Virginia mining community /

Bailey, Rebecca J., January 2008 (has links)
Based on author's thesis (doctoral)-- West Virginia University, 2001. / Includes bibliographical references (p. 267-288) and index.
278

Labour and trades unionism in the Japanese coal mining industry

Collick, R. M. V. January 1970 (has links)
No description available.
279

Estudo da contaminacao do solo e agua subterranea por elementos toxicos originados dos rejeitos das minas de carvao de Figueira no Estado do Parana

SHUQAIR, SHUQAIR M.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:26Z (GMT). No. of bitstreams: 1 08354.pdf: 6557210 bytes, checksum: 0c6cea793150b2683fda13b9ec421168 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
280

Estudo da contaminacao do solo e agua subterranea por elementos toxicos originados dos rejeitos das minas de carvao de Figueira no Estado do Parana

SHUQAIR, SHUQAIR M.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:19Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:26Z (GMT). No. of bitstreams: 1 08354.pdf: 6557210 bytes, checksum: 0c6cea793150b2683fda13b9ec421168 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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