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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.
91

Geochemical impact of super-critical C02 injection into the St. Peter Sandstone Formation within the Illinois Basin : implication for storage capability in a carbon dioxide sequestrian system

Thomas, Richard Michael January 2014 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Deep injection of waste CO2 and fluids from regional energy plants into the St. Peter Formation of the Illinois Basin, could effectively provide long term deep geologic storage. This research aims to explore the viability of this proposed injection. There are some basic criteria that must be met to effectively store waste in a geologic reservoir. First, the reservoir must have sufficient porosity and permeability for both injectivity and for migration of the injected fluid through the reservoir. Second, the reservoir must be overlain by some form of impermeable seal or cap layer(s). Third, the reservoir should be sufficiently isolated from interaction with surface and near surface water. Finally, the formation must contain enough storage volume to handle significant amounts of injected material. Massive sandstone formations that host large saline aquifers have the potential to serve as high capacity storage sites. Much of the research targeting the potential suitability and storage capacity attributes of these formations has been promising, but reproducibility of the results has been less than ideal. Some of this variability has been attributed to petrological differences in the sandstone reservoirs that are not readily evident when studying the target formation over a geographically significant area. Based on the criteria, a promising candidate for injection and storage is the St. Peter Sandstone of the Illinois Basin. This study investigates the viability of liquefied CO2 storage within the St. Peter Sandstone on a micro scale. Initial porosity and permeability of the formation plug samples ranged from 16% to 19% and 26 to 981 millidarcies (mD), respectively. The wide difference in permeability is attributed to variations in strength of the cement, in this case quartz overgrowth in the sandstone. This preliminary evidence indicates that the storage capacity of the formation will remain constant or increase depending on injection location, suggesting that the St. Peter Formation will lend itself well to future storage.
92

Economic Resilience, Disasters, and Green Jobs: An Institutional Collective Action Framework

Ismayilov, Orkhan M. 12 1900 (has links)
This dissertation is about economic resilience of local governments to natural disasters. Specifically, the dissertation investigates resilience on regional level. Moreover, the dissertation also investigates growth in the green job sector in local governments. The findings indicate that local governments working with each other helps green job creation. In addition, the dissertation finds that green jobs, following disasters, experience three percent growth. This dissertation is important because it investigates the relationship between climate- related disasters and green jobs, which is an area that is under-investigated.
93

Clean technology transition potential in South Africa's gold mining sector : case of Harmony's Kusasalethu Mine

Chavalala, Bongani 03 July 2014 (has links)
Countries and governments around the world have accepted the scientific argument on the prevalence and the possible effect of global warming and climate change on the environment, world economy and ultimately human life (Nhamo, 2011). Amongst all industrial corporations, the mining industry is the biggest environmental polluter due to its extractive nature and energy intensive operations. However because of its economic importance, it cannot be abandoned, instead it needs to find a win-win situation, where it continues to succeed but minimizes environmental damage. This thesis aims to examine the possible impact of clean technology on the sustainability of South African gold mining sector. Specifically, the study aims to determine the drivers behind the move towards clean technologies and methods, identify challenges and opportunities associated with this transition at Harmony Gold’s Kusasalethu mine. This was achieved through using Kusasalethu as a case study to which investigations of the effectiveness of clean technology and methods were carried out. The case study was multidimensional; exploring the effect of clean technology on energy consumption, greenhouse gas emission (GHG), water consumption, cyanide management and Kusasalethu’s financial performance. While the case study was largely qualitative it involved quantitative data analysis that had to be triangulated with other data sources and data gathering instruments to achieve legitimacy. This meant that the study had to adopt the mixed research methods. The instruments used included; key informant interviews, and document analysis, structured questionnaire and a set of open ended questions that served as interview guide. The qualitative data were analyzed by means of coding, descriptions, typologies, taxonomies and visual representations, whilst quantitative data were processed through Microsoft Excel to generate various forms of descriptive statistics. The findings indicate that resource consumption (energy, water, cyanide) depends on the mine design and gold output rate. Clean technology implementation at Kusasalethu helped the mine reduce energy consumption and GHG emissions. However scope 2 (indirect GHG emissions associated with energy consumption) is also determined by coal production technologies and methods used by coal mines. Although data on Kusasalethu water and cyanide management and related technologies was not available, the aggregate data for all Harmony Gold mines indicated higher annual water and cyanide consumption during 2010 and 2012. In terms of Kusasalethu’s financial performance and clean technology adaptation, acquisition of clean technologies increased capital expenditure temporarily. However, the positive effects of the clean technology transition and implementation minimized operational cost and increased operational profit greatly. Although adopting clean technologies calls for increased capital expenditure, this study reveals that this expenditure pays off in lower operation costs for the mine and the environment benefits through lower GHG emission. However, clean technologies are yet to impact significantly in lowering water and cyanide consumption levels as they do with energy consumption. The study concluded that clean technology and methods played a positive role on Kusasalethu’s environmental impact and financial performance by reducing energy consumption and GHG emissions. Though, more need to be done in terms of water and cyanide management. / Environmental Sciences / M. Sc. (Environmental Management)
94

Economic analysis of biofuels production in arid regions

Ruskin, Helen Ann Kassander. January 1983 (has links)
The objective of this study is to develop a model to evaluate the economic feasibility of biofuels production, and in particular to isolate the variables crucial to feasibility. The model constructed to define these variables is unique in its ability to accommodate a variety of plants and to integrate all portions of the production process; it was tested on a case study of a Euphorbia lathyris industry. The model minimizes costs of production to determine the best configuration for the industry. Total cost equals the sum of costs incurred in each segment of the process: growth, harvest, transport, and extraction. The solution is determined through a non-linear transportation- transshipment algorithm which describes production as a series of nodes and links. Specific application of the model was analysis of E. lathyris biofuel production in Arizona. Simulations were run examining the sensitivity of biocrude cost to changes in input parameters. Conclusions are summarized as follows. * No change in any single element can reduce final cost sufficiently to enable competitive production in the near future. * The major factor necessary to bring cost into range is improvement in biological yield. Two components of equal importance are tonnage produced per acre and percentage extractables recovered in processing. * Lowering cropping costs provided the most effective improvements of economic inputs. Perennial crops significantly reduced farm costs. * Transportation costs outweighed economies of scale in extraction; extractor location close to crops is more efficient than centralized. The cost minimization model was successfully used to isolate the critical factors for an E. lathyris industry in an arid region. Results determine that this industry would not be competitive in Arizona without dramatic improvements in yields and moderate changes in a combination of input costs. Viability is critically dependent on improvements in tonnage yield produced per acre and percent extractables recovered.
95

Clean technology transition potential in South Africa's gold mining sector : case of Harmony's Kusasalethu Mine

Chavalala, Bongani 03 July 2014 (has links)
Countries and governments around the world have accepted the scientific argument on the prevalence and the possible effect of global warming and climate change on the environment, world economy and ultimately human life (Nhamo, 2011). Amongst all industrial corporations, the mining industry is the biggest environmental polluter due to its extractive nature and energy intensive operations. However because of its economic importance, it cannot be abandoned, instead it needs to find a win-win situation, where it continues to succeed but minimizes environmental damage. This thesis aims to examine the possible impact of clean technology on the sustainability of South African gold mining sector. Specifically, the study aims to determine the drivers behind the move towards clean technologies and methods, identify challenges and opportunities associated with this transition at Harmony Gold’s Kusasalethu mine. This was achieved through using Kusasalethu as a case study to which investigations of the effectiveness of clean technology and methods were carried out. The case study was multidimensional; exploring the effect of clean technology on energy consumption, greenhouse gas emission (GHG), water consumption, cyanide management and Kusasalethu’s financial performance. While the case study was largely qualitative it involved quantitative data analysis that had to be triangulated with other data sources and data gathering instruments to achieve legitimacy. This meant that the study had to adopt the mixed research methods. The instruments used included; key informant interviews, and document analysis, structured questionnaire and a set of open ended questions that served as interview guide. The qualitative data were analyzed by means of coding, descriptions, typologies, taxonomies and visual representations, whilst quantitative data were processed through Microsoft Excel to generate various forms of descriptive statistics. The findings indicate that resource consumption (energy, water, cyanide) depends on the mine design and gold output rate. Clean technology implementation at Kusasalethu helped the mine reduce energy consumption and GHG emissions. However scope 2 (indirect GHG emissions associated with energy consumption) is also determined by coal production technologies and methods used by coal mines. Although data on Kusasalethu water and cyanide management and related technologies was not available, the aggregate data for all Harmony Gold mines indicated higher annual water and cyanide consumption during 2010 and 2012. In terms of Kusasalethu’s financial performance and clean technology adaptation, acquisition of clean technologies increased capital expenditure temporarily. However, the positive effects of the clean technology transition and implementation minimized operational cost and increased operational profit greatly. Although adopting clean technologies calls for increased capital expenditure, this study reveals that this expenditure pays off in lower operation costs for the mine and the environment benefits through lower GHG emission. However, clean technologies are yet to impact significantly in lowering water and cyanide consumption levels as they do with energy consumption. The study concluded that clean technology and methods played a positive role on Kusasalethu’s environmental impact and financial performance by reducing energy consumption and GHG emissions. Though, more need to be done in terms of water and cyanide management. / Environmental Sciences / M. Sc. (Environmental Management)
96

Influence des concentrations sur l'achèvement et le fonctionnement de marché intérieur de l'énergie / Influence of concentrations on the completion and operation of the internal energy market

Stoynev, Ivan 04 July 2011 (has links)
La réalisation du marché intérieur de l’énergie constitue le moyen de diminuer le coût de l’énergie pour les consommateurs tout en assurant d’autres objectifs tels que la sécurité d’approvisionnement. Toutefois, les marchés européens du gaz et de l’électricité connaissent de nombreuses défaillances identifiées par la Commission dans son rapport résultant d’une enquête sectorielle lancée en 2005. Les directives de libéralisation ne suffisant pas, elle prône une application renforcée du droit de la concurrence, en particulier du droit du contrôle des concentrations. L’objet de cette étude est dès lors d’analyser l’utilisation de ces règles dans le cadre du processus de libéralisation des marchés énergétiques en Europe.Après une explication de la vague de concentrations ayant eu lieu dans le secteur énergétique sous l’impact de la libéralisation et du contexte qui l’entoure, on s’intéresse à l’utilisation des règles du contrôle des concentrations. Cette étude tente de mettre en exergue l’utilisation orientée de ses règles. Les Etats membres tout d’abord tendent à favoriser les opérations de concentrations se produisant entre des entreprises nationales tout en posant des obstacles aux opérations impliquant l’entrée sur leurs territoires d’acteurs étrangers.La Commission quant à elle favorise les concentrations de nature transfrontalière afin d’aider à la réalisation du marché intérieur et au développement de l’aspect concurrentiel de ce marché. Pour ce faire, elle a recours à un outil particulier : les remèdes. De tels rapprochements entre entreprises favorisant le marché intérieur, il n’est pas dans l’intérêt de la Commission de les interdire. Les remèdes permettent d’éliminer les effets négatifs qui pourraient résulter d’une opération de concentration. Cette étude propose une analyse des différents remèdes ayant été acceptés par la Commission afin de résoudre un problème de concurrence. / The completion of the internal energy market is the way to reduce energy costs forconsumers while providing other objectives such as security of supply. However,European gas and electricity markets are experiencing many failures identified by theCommission in its report published in 2007. The Commission advocates a strongerapplication of competition law, in particular the rules of merger control because theliberalization directives was not enough. Therefore the purpose of this study istherefore to analyze the application of those rules in the process of liberalization ofenergy markets in Europe.After an explanation of the merger wave that occurred in the energy sector under theimpact of liberalization and the environment that surrounds it, we are interested in theapplication of the rules of merger control.In this scope we will see that the Commission encourages the concentration of crossbordernature to help build the internal market and to develop the competition. Torealize this objective, the Commission uses a particular tool: the remedies. Theremedies can eliminate the negative effects that could result from a merger. Thisstudy provides an analysis of the various remedies that have been accepted by theCommission to resolve the problems of competition.
97

An assessment of household energy use, emissions and deforestation in the Thulamela Local Municipality

Ahunamure, Solomon Eghosa 02 February 2016 (has links)
MENVM / Department of Geography and Geo-Information Sciences / Fuel wood is regarded as a major source of energy around the world, particularly in developing nations. Most rural communities around the world, consider forests as the repository of stored energy. The high dependence on forests as a source of fuel wood has a major impact on vegetation because trees take a long time to regenerate to maturity, hence high dependence leads to deforestation. Fuel wood is used for household needs, such as cooking and heating and its uses contribute to the emissions of Green House Gases (GHG) such as CO2, CH4, and Black Carbon amongst others. The study assesses household energy use, the amount of carbon dioxide emitted from the combustion of fuel wood, the extent of de-vegetation and strategies to ensure sustainable energy provisions in the case study areas. Primary and secondary methods were used to collect data. The data were analysed using Statistical Package for the Social Sciences (SPSS 21.0), showing the frequency distribution, measures of central tendency and chi-square to determine the extent of fuel wood used in relation to electricity. The primary data were collected through personal observations, field surveys, interviews and questionnaires, while secondary data included the 2011 South Africa Census data and remote sensing images, which with the aid of GIS, were used in mapping the vegetation change.
98

A techno-socio-economic potential assessment of organic waste-to- energy conversion through biogas technology for rural households in Vhembe District of Limpopo

Rasimphi, Thilivhali Eugene 02 February 2016 (has links)
MENVSC / Department of Ecology and Resource Management
99

Evaluation of the suitably of proposed site for construction of photovoltaic solar facility at Kakamas in the Northern Cape of South Africa

Tshilate, Lindelani 18 May 2019 (has links)
MESMEG / Department of Mining and Environmental Geology / Solar energy development is experiencing significant growth due to national interest in increasing energy efficiency, reducing dependence on fossil fuels, increasing domestic energy production, and curbing greenhouse gas emissions. Northern Cape is generally known to be one of the preferred areas for the generation of solar energy in South Africa, and even in the world, due to its abundant solar radiation. Although this area has abundant potential for solar power generation, not all the areas are suitable for construction of solar plant facilities especially those that are prone to sand storm and dust accumulation. Consequently, site evaluation is very crucial for planning, design and construction of the solar facility. The main objective of this study was to determine the suitability of a proposed site at Kakamas in the Northern Cape for construction of a photovoltaic solar facility. The specific objectives of this research were to assess and establish all the geotechnical aspects that may have an impact on the development of the site, to explore the surface conditions at the proposed site and to establish the soil properties and comment on the use of the on-site soils in the construction of the solar facility. Other specific objectives included to determine the variability of ground conditions and effects of such variability on the proposed development and to provide foundation recommendations for the design and construction of the solar facility. In order to obtain this information, methods such as desktop studies, geological survey, soil survey, magnetic survey and soil profiling were employed to obtain information about the geotechnical aspects of the study area and properties of the on-site soil. Field tests such as cone penetration and resistivity survey and laboratory tests such as foundation indicator test, California Bearing Ratio, pH and permeability test were also performed in order to determine the engineering, behavioral and hydraulic properties of the soil. The results of the geologic and magnetic survey indicated that the study area is underlain by mainly igneous and metamorphic rocks such as gneiss, quartzite, pegmatite, gneiss and calcrete. The results of the soil profiling and the resistivity survey showed that the study area is comprised of sandy soil with either two or three horizons while the cone penetration results revealed high variable soil consistency and stiffness which ranged from very loose to very stiff soils. The particle size distribution, atterberg limits and grading modulus indicated that the study area is characterized mainly by dry, cohesionless and non-plastic to slightly plastic coarse-grained sandy soil with sand content ranging from 71- 96%. From the CBR results, it was found that the soils in the study area generally classifies as G6 material and can be used as base, sub base and backfilling material in accordance with the TRH 14 specifications. The permeability test results indicated moderately permeable sandy silt soils with coefficient of permeability ranging between 1x10-3 to 8x10-3 cm/sec and ground water was encountered at 1.3 m depth. The material excavatability indicated variable material on site ranging from soft calcretes with soft excavation to highly competent material such as quartz and dorbank which require hard excavation while the side wall stability of trial pits indicated stable pit walls during the investigation giving an indication of stability of long pit excavations. The foundation analysis showed that driven piles and earth screws are the ideal foundation types for this site and that the site is generally suitable for construction of the solar facility provided all the recommendations are implemented. / NRF

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