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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 expected value of catastrophes in underground coal mines 1987-2001

Alexander, Danrick W. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xii, 226 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references (p. 214-225).
2

Descriptions of coal associated diseases and coal dust concentrations in Mpumalanga coal mines

Du Toit, Andreas Zacharias 16 September 2010 (has links)
MPH, Occupational Hygiene,School of Public Health, Faculty of Health Sciences, University of the Witwatersrand / Introduction Coal mine workers are exposed to a mixture of dusts including coal dust and silica (as alpha quartz), in this respect the mixture of dusts is termed mixed coal dust. The illnesses commonly associated with the inhalation of mixed coal dust are (1) coal workers’ pneumoconiosis, (2) silicosis, and (3) chronic obstructive pulmonary disease. Objectives The main aim of this research report is to determine whether current dust levels in Mpumalanga coal mines were above generally recommended standards and to review information on the burden of coal associated diseases in the coal miners of Mpumalanga. The objectives of this research project are (1) to describe the coal dust and silica concentrations as measured by personal breathing zone sampling in Mpumalanga coal mines over the period 2003 to 2006 and (2) to describe the burden of coal-associated diseases reported by autopsy examinations received from NIOH Pathology Department and in the SAMODD data base in Mpumalanga coal mines over the period 2002 to 2006. Page 4 of 71 Methods Dust Personal breathing zone sampling data were obtained from gravimetric sampling programmes established according to the DMR – SAMOHP from fifty three coal mines in the Mpumalanga region. During the time of the study, the sampling programme strategies were co-ordinated by a central laboratory services: “Colliery Environmental Control Services”. The raw data were obtained from this laboratory for the periods 2003 to 2006 in Microsoft excel spread sheet format. Burden of disease NIOH - PATHAUT The annual reports of the NIOH on the autopsy data for the coal mining sector were obtained from the web site of NIOH. Sample data sheets were drawn up to extract only relevant information from the reports. DMR - SAMODD The DMR collects medical information from coal mines across South Africa, and this information was obtained from the local inspectorate. The data contained in the report were of all the mines in South Africa, a filter was applied in a Microsoft Excel spread sheet to extract the relevant information for Mpumalanga coal mines. Page 5 of 71 Results Dust There was a reduction in the recorded concentration of respirable dust levels in the collieries over the four year period 2003 to 2006. The average coal dust exposures fell from 1.9 mg/m³ in 2003 to 1.3 mg/m³ in 2006. The Department of Mineral Resources places emphasis on the 90th percentile and most of the sampling strategies are centred on this figure. Although the 90th percentile decreased from 4.82 mg/m³ to 3.02 mg/m³ (i.e. 1.8 mg/m³) over the four year period, this level is still unacceptable as it is above the required statutory limit of 2.0 mg/m³. Silica exposures also showed a reduction from an average of 0.047 mg/m³ in 2003 to 0.034 mg/m³ in 2006. Disease burden: PATHAUT Pulmonary tuberculosis - the number of employees at autopsy with pulmonary tuberculosis (PTB) decreased from 12 in 2002 to 8 in 2006, but there is not enough information to establish a trend over the five year period. Silicosis: - the number of employees at autopsy with silicosis was between 3 to 4 cases per year except in 2004 where there was an outlier of 11, but in general the cases stayed constant over the five year period. The rate of silicosis per 1000 Page 6 of 71 autopsies however indicates an increase over the five year period as the rate increased from 37 to 52. Emphysema: - the number of emphysema cases stayed fairly constant with 32 cases in 2002 and 30 cases in 2006, but with an increase in 2003 and 2004 to 42 and 43 respectively. The rate per 1000 autopsies increased from 294 in 2002 to 390 in 2006. Coal workers’ pneumoconiosis: - there was a decrease in coal workers’ pneumoconiosis from 2002 to 2006 from 10 to 2 cases, but there were 11 and 15 cases in 2003 and 2004. SAMODD Coal workers’ pneumoconiosis: - the total number of employees reported with Coal Workers Pneumoconiosis (CWP) decreased for the period 2003 to 2006, from 12 in 2003 to three in 2006. Chronic obstructive pulmonary disease: - No useful information was available for this illness. Silicosis: - One case was reported in 2002, and 2 cases in 2003 and 2004, no cases were reported for 2005. Tuberculosis: - with initially only three cases in 2002, cases increased during 2003 to 2005 to 53, 44 and 50 respectively. A reduction was observed in 2006 to 13 cases. Page 7 of 71 Conclusion There may be an overall reduction in the dustiness of the coal mining industry in Mpumalanga province as the arithmetic mean of the samples collected decreased from 1.9 to 1.3 mg/m³ over the four year period 2003 to 2006. The level of exposures to silica might be lower because the exposures reduced from a mean of 0.047 in 2003 to a mean of 0.034 mg/m³ in 2006. The recorded data suggest a decline in CWP; this is in line with international data from the United Kingdom, USA, Australia, Germany, France and Belgium. Pulmonary tuberculosis - was constant over the five year period based on limited autopsy data, but the SAMODD data base indicates a decline for the year 2006 but overall shows an increase in the number of tuberculosis cases in Mpumalanga coal mines. Silicosis cases were fairly constant, but the rate per 1000 autopsies increased by 15/1000 over the five year period. The number of recorded cases from the DMR SAMODD is too few to make any useful deductions. Emphysema numbers were constant, but the rate per 1000 autopsies increased by 96/1000 over the five year period. No useful interpretation can be made from the data received from the DMR on chronic obstructive pulmonary disease.
3

Assessment of coal mine stockpiled soil quality and its impact on vegetation using laboratory-based techniques and reflectance spectroscopy

Mushia, Nicacias January 2018 (has links)
Thesis (Ph.D. (Agriculture)) -- University of Limpopo, 2018 / Surface coal mining requires good and sound rehabilitation practices to re-establish productive land capability and land use after mine-closure. The vast majority of Mpumalanga’s coal deposits are located below high quality and productive arable land. Impacts on soil and land, associated with surface coal mining can reduce the possibility to re-establish the pre-mining land capability and productive potential. Stockpiled soils are excavated from the ground during mining activities, and piled on the surface of the soil for rehabilitation purposes. These soils are often characterized by low Soil Organic Matter (SOM) content, low fertility, and poor physical, chemical and biological properties, limiting their capability for sustainable vegetation growth. The aim of this study was to assess coal-mine stockpile soil quality and its impacts on vegetation using laboratory techniques and Reflectance Spectroscopy. Firstly, the impact of quality of coal-mine stockpile soils on sustainable vegetation growth and productivity was investigated. Soils were collected at three different depths (surface (0-25cm), mid (150-200cm) and deep (300-350cm)), as well as mixed (equal proportion of surface, mid and deep) from two stockpiles (named stockpile 1: aged 10 and stockpile 2:20 years) at the coal mine near Witbank in Mpumalanga Province, South Africa. Soils were amended with different organic and inorganic fertilizer. A 2 x 4 x 5 factorial experiment in a randomized complete block design with four replications was established under greenhouse condition. A grass species (Digiteria eriantha) was planted in pots with unamends and amended soils under the greenhouse condition at ambient temperatures of 26-280C during the day and 16.5-18.50C at night. Mean values of plant height, plant cover, total fresh biomass (roots, stems and leaves) and total dry biomass were found to be higher in the stockpile 1 than in stockpile 2 soils. On average, plants grown on soils with amendments yielded plant height that was 98.28% higher than plants grown on soil with no amendment. On average, height of plants grown on soil amended with poultry manure and lime was 44.65% higher compared to plants planted on soils amended with NPK + lime, compost and poultry manure. On average, mixed soils had better vegetation growth than soil from the individual depths. In total, dry biomass and plant height of plants grown on mixed soils was 33.56% and 22.34% higher than plants grown on surface, mid and deep soils. Mixing soils changes texture, which might affect other physical properties like water availability, infiltration rate and aeration and, to some extent, chemical properties.Secondly, the effect of soil amendments on enzyme activity of coal-mine stockpile soil was investigated. The activity of β-glucosidase, alkaline phosphatase, acid phosphatase and urease was analysed after harvest of grass species (Digiteria eriantha). The results show significantly high activity for β-glucosidase, alkaline phosphatase and urease when soils were amended with poultry manure + lime. Soils with no fertilizer yielded significantly low enzyme activity compared to soil amended with poultry manure+ lime, NPK + lime, sole application of poultry and in some instances compost application. β-glucosidase, urease and acid phosphatase mean values generally tend to decrease with an increase in soil depth. β-glucosidase activity for surface soil was found to be 18.06% higher than that of mid and deep soil. The stockpile depth plays a major role in biochemical activities of the soil; deep soils, in most cases, have decreased microbial biomass and enzyme activity due to oxygen and moisture availability. The results for the effect of organic and inorganic amendment on stockpile soil showed that on average, alkaline phosphatase activity following the application of poultry manure + lime was 17.69% higher than that of lime + inorganic fertilizers (NPK). On average, the acid phosphatase activity following the application of lime + NPK was 56.33% higher than that of poultry manure + lime, compost, soil with no fertilizer as well as sole poultry manure. Urease activity for soil with no fertilizer was found to be 84.70% lower than that of soil amended with poultry + lime. The increase in enzyme activity was attributed to change in soil pH due to application of amendments. A comparison of the two stockpiles indicated that, stockpile 2 (20-year old) had low enzyme activity compared to stockpile 1 (10-year old). The activity of β-glucosidase, acid phosphatase, alkaline phosphatase and urease was found to be 11.03%, 8.04%, 10.03% and 60.23% respectively, higher on stockpile 1, relative to stockpile 2 soils. When soils are stockpiled for a long period of time, microbial biomass is reduced and that affect enzyme activity because microbial biomass is considered as the primary source of enzymes in the soil. Thirdly, the capability to estimate coal-mine stockpile soil properties using Reflectance Spectroscopy was investigated. Soil from coal-mine stockpiles were air dried, crushed, sieved and analysed using laboratory methods. The following soil properties: exchangeable calcium (Ca), sodium (Na), magnesium (Mg), potassium (K), soil pH, organic carbon (OC), phosphorus (P) and clay content were analysed as they are important for vegetation re-establishment during rehabilitation. Spectral reflectance of the soil samples was measured using FieldSpec 3 Portable Analytical Spectral Device (ASD®) spectrometer. Partial Least Square Regression (PLSR) was used to estimate various soil properties, in combination with various spectral transformation techniques such as untransformed reflectance spectra, First Derivative Reflectance (FD) and Log transformed spectra Log (1/R). To assess the performance of various predictive models, R2 (Coefficient of Determination), Root Mean Squares Error of Validation (RMSEV) and Variable Importance in the Projection (VIP) values were computed. The results showed that pH and Ca were accurately estimated (R2=0.79 and 0.69 and RMSEV=0.52 and 0.89cmol/kg respectively) using Log (1/R) reflectance as compared to other soil properties achieving R2 less than 0.5. Ca has strong correlation with pH. Ca expressed in soil solutions is mostly related to pH, which is what was attributed to accurate prediction of both Ca and pH. Soil pH in most cases is directly influenced by calcium carbonate content in the soil. Although the performance of other soil properties was poor, they were highly correlated with pH and Ca except for K. K is soluble and mobile and is therefore subject to leaching in most soils resulting in low K concentrations. Low K concentrations results in higher variability and lower R2 values.Finally, the capability of Partial Least Square Regression and Reflectance Spectroscopy to estimate the effect of coal-mine stockpile soil on foliar nitrogen and phosphorus content was investigated. Grass samples were collected from coal-mine stockpile soils and the adjacent unmined soils at open-cast coal mine around Witbank area in Mpumalanga Province, South Africa. Samples were oven dried and analysed for foliar N and P concentration in the laboratory. Spectral reflectance of the dried grass samples were measured using Analytical Spectral Device (ASD) - FieldSpec 3. Partial Least Square.Regression (PLSR) was used to estimate N and P concentration, in combination with various spectral transformation techniques such as First Derivative Reflectance (FDR) and Log transformed spectra Log (1/R). The results show that stockpile soils appear to impact foliar N and P concentration as evidenced by low N and P concentration in the grass, sampled from stockpile soils compared to grass sampled from unmined soils. This was attributed to soil nutrient status of the study sites, as unmined sites had high soil nutrient content than stockpile soils. Foliar N concentration of grass sampled from stockpile soils and unmined soils can accurately be estimated without spectral transformation. FD yielded highest R2 for N and P estimation in grass sampled from both stockpile soils and unmined soils.Overall, the study shows that stockpiling affect soil quality, enzyme activity and vegetation growth. It further shows that soil amendments can improve soil quality and enzyme activity of coal-mine stockpile soils. Finally, Reflectance Spectroscopy can be used to estimate coal-mine stockpile soil properties, its quality and foliar N and P content as an indicator of vegetation nutrient stress. / National Research Foundation
4

Long-term stability of major coal mining tunnel projects

Kapusniak, S. January 1986 (has links)
No description available.
5

Laboratory studies of pumping characteristics of processed liquid tailings with particular reference to stability and time dependant properties

Barkhordarian, A. January 1988 (has links)
No description available.
6

Coal waste deposition and the distribution of freshwater mussels in the Powell River, Virginia /

Wolcott, Lisa Terwilliger, January 1990 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1990. / Vita. Abstract. Includes bibliographical references (leaves 85-90). Also available via the Internet.
7

A study of the relationship between coal mine fatalities and the length of time a mine has been opened

Dorset, Nancy L., January 1900 (has links)
Thesis (M.S.)--West Virginia University, 2002. / Title from document title page. Document formatted into pages; contains xi, 106 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 103-105).
8

Development of acid rock drainage prediction methodologies for coal mine wastes

Stewart, Warwick January 2005 (has links)
Acid rock drainage (ARD) is recognised as one of the most serious environmental issues currently facing the mining industry. ARD management strategies rely heavily on the ability to measure the ARD potential of waste materials to ensure strategies are appropriate to the ARD risks. It is apparent that improvements to the understanding of ARD test methods and development of methods to better represent the ARD potential of samples will contribute significantly to the value and reliability of ARD assessment. The research described in this thesis focused on critical assessment and improvement of: ARD test methodology; approach to testing; and interpretation of results for coal mine wastes. Kaltim Prima Coal Mine (KPC) in Kalimantan, Indonesia was selected as a case study site to help focus the research, with the understanding that the broad similarities of coal sequences in general would allow broader application of the findings. / Thesis (PhDApSc(MineralsandMaterials))--University of South Australia, 2005
9

Development of acid rock drainage prediction methodologies for coal mine wastes /

Stewart, Warwick. January 2005 (has links)
Acid rock drainage (ARD) is recognised as one of the most serious environmental issues currently facing the mining industry. ARD management strategies rely heavily on the ability to measure the ARD potential of waste materials to ensure strategies are appropriate to the ARD risks. It is apparent that improvements to the understanding of ARD test methods and development of methods to better represent the ARD potential of samples will contribute significantly to the value and reliability of ARD assessment. The research described in this thesis focused on critical assessment and improvement of: ARD test methodology; approach to testing; and interpretation of results for coal mine wastes. Kaltim Prima Coal Mine (KPC) in Kalimantan, Indonesia was selected as a case study site to help focus the research, with the understanding that the broad similarities of coal sequences in general would allow broader application of the findings. / Thesis (PhDApSc(MineralsandMaterials))--University of South Australia, 2005.
10

Development of acid rock drainage prediction methodologies for coal mine wastes

Stewart, Warwick January 2005 (has links)
Acid rock drainage (ARD) is recognised as one of the most serious environmental issues currently facing the mining industry. ARD management strategies rely heavily on the ability to measure the ARD potential of waste materials to ensure strategies are appropriate to the ARD risks. It is apparent that improvements to the understanding of ARD test methods and development of methods to better represent the ARD potential of samples will contribute significantly to the value and reliability of ARD assessment. The research described in this thesis focused on critical assessment and improvement of: ARD test methodology; approach to testing; and interpretation of results for coal mine wastes. Kaltim Prima Coal Mine (KPC) in Kalimantan, Indonesia was selected as a case study site to help focus the research, with the understanding that the broad similarities of coal sequences in general would allow broader application of the findings. / Thesis (PhDApSc(MineralsandMaterials))--University of South Australia, 2005

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