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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

Эколого-экономические аспекты формирования налоговой политики промышленного предприятия при размещении отходов производства на земле : магистерская диссертация / Ecological and economic aspects of the formation of the tax policy of an industrial enterprise when disposing of production waste on the earth

Косточко, К. А., Kostochko, C. A. January 2019 (has links)
С точки зрения экологизации производственных процессов перед исследователями и промышленниками, перед муниципальными властями выдвигается необходимость обеспечить максимально возможную безвредность технологических процессов и полное использование всех отходов производства, а с точки зрения экономики возникает необходимость минимизации затрат предприятия, путем ведения его эффективной налоговой политики в области землепользования, а также разработки методов стимулирования к рациональному использованию земли. Целью магистерской диссертации является разработка модели налогового поведения промышленного предприятия при размещении отходов производства на земле. Анализ основывался на рассмотрении техногенной нагрузки на земли и почвы Свердловской области, а также изучении существующих методов и инструментов управления налоговой нагрузкой промышленного предприятия в части использования земель. В качестве источников информации использовались нормативно-правовые акты РФ, база публикаций Российского индекса научного цитирования, представленная на ресурсе Elibrary, статистические данные по исследуемой тематике, данные отчетности ФНС. В ходе написания магистерской диссертации была разработана и апробирована модель налогового поведения отходопроизводителя. Использование данной модели нацелено на снижение налоговой нагрузки отходообразующего предприятия в части использования земель путем оптимизации налоговых платежей, учитывая интересы налогоплательщика и экологическую обстановку в регионе. Предложен авторский подход к совершенствованию размера платы за пользование земельным ресурсом (налог на землю, арендная плата, нормативная цена земли), в основу которого положен принцип дифференциации ставок, что обусловит внедрение технологий утилизации в целях сокращения площади занимаемых земель. В результате апробации разработанной модели был выявлен вариант эффективного налогового поведения с максимально возможной экономической выгодой. / From the point of view of greening production processes, researchers and industrialists, municipal authorities are required to ensure the maximum possible harmlessness of technological processes and the full use of all production waste, and from an economic point of view, there is a need to minimize the costs of an enterprise by maintaining its effective land use tax policy, and the development of incentive methods for the rational use of land. The purpose of the master's thesis is to develop a model of the tax behavior of an industrial enterprise when disposing of production waste on the ground. The analysis was based on the consideration of the technogenic load on the land and soil of the Sverdlovsk region, as well as the study of the existing methods and tools for managing the tax burden of an industrial enterprise in terms of land use. The sources of information were the regulatory legal acts of the Russian Federation, the database of publications of the Russian Science Citation Index, presented on the Elibrary resource, statistical data on the subject under study, and data from the FTS reporting.. In the course of writing the master's thesis, a model of tax evacuation behavior was developed and tested. The use of this model is aimed at reducing the tax burden of the waste- forming enterprise in terms of land use by optimizing tax payments, taking into account the interests of the taxpayer and the environmental situation in the region. An author's approach is proposed to improve the size of payment for the use of land (land tax, rent, normative price of land), which is based on the principle of differentiation of rates, which will lead to the introduction of recycling technologies in order to reduce the area of land occupied. As a result of testing the developed model, a variant of effective tax behavior with the greatest possible economic benefit was identified.
93

Establishment of composting facilities on landfill sites

Du Plessis, Roelien 11 1900 (has links)
Waste minimisation is implemented worldwide and has become an urgent priority in South Africa as evidenced in the promulgated National Environmental Management Waste Act (2008). The most common waste disposal method in South Africa is by landfill, which is unacceptable. Local municipalities have made little progress towards waste minimisation. The aim of this study was to present a solution to waste minimisation for the City of Tshwane Metropolitan Municipality (CTMM) by determining the feasibility of establishing composting facilities on landfill sites. One third of all municipal waste consists of green waste, which is compostable and can be converted on landfill sites. Nine municipal landfill sites were screened. The four most feasible sites were evaluated further by applying identified parameters that address physical, social and operational requirements. It is a possible to establish composting facilities on all four sites investigated, with Hatherley ranking as the most suited. The findings of this study clearly provided the basic parameters and requirements for constructing a composting facility and practical procedures applicable within a South African context. The evaluation method used can be applied as a model to evaluate similar studies in other municipalities to aid them in the decision-making process for waste minimisation. / Environmental Management / M.A. (Environmental Management)
94

Exploration of the availability, development and use of learning support materials on waste management in Kwazulu Natal

Manqele, Mbaweni Beauty January 2006 (has links)
This case study was done in KwaZulu–Natal province in South Africa within two municipalities Ethekwini and Umsunduzi Municipality. Three communities participated in this study. The research is motivated by the lack of cooperation between some municipalities and Community Based Organisations (CBOs) in implementing the National Waste Management Strategy (NWMS) at a local level. The primary goal is to explore the availability and development of learning support materials (LSMs) that relates to waste management in collaboration with CBOs and local councillors. The secondary goal is to explore the use of learning support material to promote participation in the implementation of the NWMS. Coresearchers were from the Community Based Organisations as well as local councillors who are located within the communities of these CBOs. Pseudonyms for co-researchers from CBOs and Councillors and the name of their townships have been used to protect co-researchers. A literature review has been conducted to explore research that has been done on the development, usage, accessibility and distribution of the LSMs. Data collection methods included semi-structured interviews; field visits to communities, tape recording of discussions and the keeping of a field journal. Some of the key findings included that LSMs is used by both CBOs and Councillors to try to reduce local environmental problems. It also identified that there are no formal mechanisms between CBOs and Municipalities in dealing with waste management programmes within the identified communities. The other important finding was that the participation of CBOs in the development of LSMs normally excludes the user groups as a result language used is not always understood. Illustrations used in some cases may be misinterpreted if the reader is not English literate as most of material in circulation is written in English. Some recommendations for further research have been made in relation to the findings made in the study. These included recommendations on the development, usage of LSMs, participation of stakeholders in resource development within the context of CBOs and local municipalities.
95

Establishment of composting facilities on landfill sites

Du Plessis, Roelien 11 1900 (has links)
Waste minimisation is implemented worldwide and has become an urgent priority in South Africa as evidenced in the promulgated National Environmental Management Waste Act (2008). The most common waste disposal method in South Africa is by landfill, which is unacceptable. Local municipalities have made little progress towards waste minimisation. The aim of this study was to present a solution to waste minimisation for the City of Tshwane Metropolitan Municipality (CTMM) by determining the feasibility of establishing composting facilities on landfill sites. One third of all municipal waste consists of green waste, which is compostable and can be converted on landfill sites. Nine municipal landfill sites were screened. The four most feasible sites were evaluated further by applying identified parameters that address physical, social and operational requirements. It is a possible to establish composting facilities on all four sites investigated, with Hatherley ranking as the most suited. The findings of this study clearly provided the basic parameters and requirements for constructing a composting facility and practical procedures applicable within a South African context. The evaluation method used can be applied as a model to evaluate similar studies in other municipalities to aid them in the decision-making process for waste minimisation. / Environmental Management / M.A. (Environmental Management)
96

Analyse probabiliste du risque de stockage de déchets radioactifs par la méthode des arbres d'événements continus

Smidts, Olivier 23 October 1997 (has links)
Les études du risque du stockage de déchets radioactifs comprennent, comme toute étude du risque, un traitement de l'incertitude. L'outil de calcul du risque, appelé outil PRA (Probabilistic Risk Assessment), est formé d'un code de calcul d'écoulement des eaux souterraines et de transport de chaînes de radionucléides. Ce type d'outil est essentiel pour l'évaluation de performance de la barrière géologique. Le manque de connaissances au sujet de la variabilité (dans l'espace et le temps) des propriétés hydrogéologiques de cette barrière est la raison primaire de l'incertitude et des méthodes stochastiques ont été développées en hydrogéologie pour le traiter.<p>Dans cette thèse, l'analyse d'incertitude liée à la composition du milieu géologique est partagée entre l'écoulement et le transport de la manière suivante: a) une solution moyenne de l'écoulement est tout d'abord déterminée à l'aide d'un code basé sur la méthode des différences finies. Cette solution est ensuite soumise à une analyse de sensibilité. Cette analyse débouche sur la résolution d'un problème inverse afin d'améliorer l'estimation initiale des paramètres moyens d'écoulement; b) l'effet de la variation aléatoire de la vitesse d'écoulement est envisagé lors du transport des radionucléides. Le transport est résolu à l'aide d'une méthode Monte Carlo non analogue.<p><p>L'analyse de sensibilité du problème d'écoulement est réalisée à l'aide d'une méthode variationnelle. La méthode proposée a comme avantage celui de pouvoir quantifier l'incertitude de structure; c'est-à-dire l'incertitude liée à la géométrie du milieu géologique.<p>Une méthodologie Monte Carlo non analogue est utilisée pour le transport de chaînes de radionucléides en milieu stochastique. Les apports de cette méthodologie pour le calcul du risque reposent sur trois points:<p>1) L'utilisation d'une solution de transport simple (sous la forme d'une solution adjointe) dans les mécanismes de la simulation Monte Carlo. Cette solution de transport permet de résumer, entre deux positions successives du marcheur aléatoire, les processus chimicophysiques (advection, diffusion-dispersion, adsorption, désorption,) apparaissant à l'échelle microscopique. Elle rend possible des simulations efficaces de transport en accélérant les mécanismes de transition des marcheurs aléatoires dans le domaine géologique et dans le temps.<p>2) L'application de la méthode des arbres d'événements continus au transport de chaînes de radionucléides. Cette méthode permet d'envisager les transitions radioactives entre éléments d'une chaîne selon un même formalisme que celui qui prévaut pour les simulations de transport d'un radionucléide unique. Elle permet donc de passer du transport d'un radionucléide au transport d'une chaîne de radionucléides sans coûts supplémentaires en temps de calcul et avec un coût supplémentaire en mémoire limité.<p>3) L'application de techniques dites de "double randomization" au problème de transport de radionucléides dans un milieu géologique stochastique. Ces techniques permettent de combiner efficacement une simulation Monte Carlo de paramètres avec une simulation Monte Carlo de transport et ainsi d'inclure l'incertitude associée à la composition du milieu géologique explicitement dans le calcul du risque.<p><p>Il ressort de ce travail des perspectives prometteuses de développements ultérieurs de la méthodologie Monte Carlo non analogue pour le calcul du risque.<p><p> / Doctorat en sciences appliquées / info:eu-repo/semantics/nonPublished
97

Investigation of municipal solid waste management: a case study of Vhembe District Municipality, South Africa

Mathako, Khodani 20 September 2019 (has links)
MENVSC / Department of Ecology and Resource Management / The main objective of the study was to investigate the effectiveness of municipal solid waste management system, its potential implication in Vhembe District Municipality, South Africa and to recommend strategies for effective management of municipal solid waste in the district. To achieve this, structured questionnaires, interviews, field observations and focus group discussions were used to collect primary data within the district. The study focused on the four local municipalities: Makhado, Thulamela, Musina and Collins Chabane. Desktop study was also undertaken to gather secondary data by reviewing journals, technical reports, books and articles. The study adopted a mixed method approach comprising of triangulation of qualitative and quantitative design. The target groups of the study were selected through purposive sampling. The respondents in the study were 21 officials from local municipalities including directors, waste managers, superintendents, landfill supervisor and interns. Data was collected using focus group interviews and questionnaires and analysed using descriptive statistics which involve the presentation of numerical facts, or data, in either tables or graphs form. Municipalities in the district are producing a considerable amount of solid waste. Municipalities do not adhere to the existing guidelines on waste minimization at source, for example; they do not have zero waste strategy (3R) reduce, reuse and recycle, which is the highest priority of the National Waste Management Policy. Lack of the application of existing waste management policy leads to large amount of solid waste eventually ending up in landfill sites. The study recommends to municipalities to develop operational and monitoring waste management plans which will create continuous improvement on waste management. In the district, it was observed that the bulk of waste generated per month within municipalities is general waste comprising 64%, as compared to garden waste and building rubbles. There are no equipment and programs in place by municipalities to encourage waste separation at source, for example, municipalities do not have household‟s recyclable receptacles to encourage separation at source. Municipalities do not have weighbridge to quantify waste entering the site. It was observed that Thulamela and Collins Chabane Local municipalities create compost from garden waste received at the landfill sites, whereas Musina and Makhado Local Municipalities do not create compost from garden waste. Garden waste is dumped and compacted with other waste materials in the landfills. All municipalities should create compost from garden waste received at the landfill sites as it helps to extend the life span of the landfills because it v reduces the amount of waste to the landfill. There is lack of prioritization within municipalities, for example, in Makhado Local Municipality, when the new financial start, budget is allocated to other proposed projects by councilors as they consider waste management projects not a priority. It was observed that within the district, there is high level of illegal dumping in catchment areas and open spaces especially at Musina Local Municipality. Musina Local Municipality is using a quarry as disposal site which was not lined and it has led to contamination of underground water by leachate, whereas Thulamela, Collins Chabane and Makhado Local Municipalities are using lined landfill sites to avoid contamination of underground water. The available vehicles within the municipalities are not enough to meet the demand and some of them are too old, for example, tractors and trucks used by Makhado Local Municipality are 20 years old and they often breakdown, whereas Thulamela, Collins Chabane and Musina Local Municipalities are not using old vehicles as they auctioned old vehicles and bought new ones. Vhembe District Municipality should manage waste in accordance to the new approach of source separation, waste reduction, reuse and recycling by developing environmental awareness programmes supported by the placement of the recyclable receptacles at strategic points to collect recyclable materials which will reduce large amount of waste which eventually ends up in landfills. The study recommends that municipalities should have law enforcement structure which will create and enforce the laws/policies as it helps municipalities to implement effective waste management system and monitoring structure to monitor prioritization and budget allocation to avoid any wastage. Municipalities should have landfill monitoring committees to facilitate the compliance on the development and operation of the landfills to avoid the use of quarry as landfill sites. / NRF
98

An assessment of impacts of landfill composition on soil quality, heavy metal and plant health : a case of Lumberstewart landfill in Bulawayo, Zimbabwe

Makuleke, Peace 02 1900 (has links)
Landfills have served as the major sites for waste disposal in both developed and developing countries. Upon closure of a landfill site, the surface could be converted to a golf course, recreation park, playground, animal refuge, tennis court and industrial site. Even when closed, landfills still have the potential to contaminate the surrounding environment as a result of the migration of leachate from decomposing waste contained in the site. This study focused on assessing the impacts of a closed landfill on soils and plants at Lumberstewart closed landfill site in Bulawayo, Zimbabwe. Soil samples were collected at three different depths (0-30 cm, 30 - 60 cm and 60-90 cm) at the landfill and a control site. The soil samples were analysed for their texture, pH, electrical conductivity, organic matter content, cation exchange capacity and concentrations of Cd, Cu, Cr, Fe, Ni and Zn. Samples of jimson weed and pigweed growing at the closed landfill and the control site were collected from the same sites where soil samples were collected, and the concentrations of the same set of heavy metals in these weeds determined. Soil samples were digested using EPA method 3050B: Acid Digestion of Sediments, Sludge and soils whereas nitric acid and hydrogen peroxide was used for digestion of plant samples. Both plant and soil digests were analyzed for heavy metals concentrations using Flame Atomic Absorption Spectrometry (AAS). Soils from the landfill as well as the control site had a high content of sand with soil pH values which were alkaline. The electrical conductivity values of the soil samples were relatively low ranging from 0.39 to 1.67 dS/m, indicating low levels of salts in soils at the landfill. The concentrations of heavy metals at the closed landfill site were higher than the control site. Heavy metals concentrations in soils at the closed landfill followed the order Fe>Zn>Cu>Cr>Ni>Cd. Results indicated that Fe was exceptionally higher than the other metals with concentration values averaging 45690±17255 mg/kg. Cadmium on the other hand had the least concentration with values of 0.01±0.00 mg/kg. Values of Enrichment Factors of heavy metals around the soil at different depths indicated that the enrichment of heavy metals increased with depth at the landfill up to 30-60 cm after which a decrease was observed. Values for heavy metal Contamination Factor of soils around the landfill ranged from low concentration (CF<1) to very high concentration (CF>6). The Pollution Load Index (PLI) values for the soil at the Lumberstewart landfill indicated that all sites were polluted (PLI>1). Site 6 had significantly higher mean concentration of heavy metals in soils at the landfill whereas site 11 had the least. The concentrations of Cd and Ni in soils at the landfill were below permissible limits of South African National Norms and Standards (NNS) as prescribed by NEMA (2008) in South Africa whereas Cr, Cu and Zn in soils were above the NNS permissible limits. Heavy metal concentrations in soils at the landfill were above World Health (WHO) permissible limits except for Cd which was equal (0.01 mg/kg) to the permissible values of Cd in the soils at sites 5, 8, 9, 10, 11 and 12. Mean concentrations of heavy metals in jimson weed and pigweed were in the order Fe>Zn>Cu>Cr>Ni>Cd. The concentrations of Cd, Cr, Cu, Fe and Zn in both plants from all sites at the landfill were significantly higher than the control site. Heavy metal transfer coefficient for both plants indicated that heavy metal uptake was more species dependent than soil heavy metal concentration dependent. The results from this research indicate that though the Lumberstewart Landfill has been closed, it is still affecting the soils in the vicinity of the landfill. Plants and water around the Lumberstewart closed landfill could be at risk from heavy metal contamination. High concentrations of heavy metals observed in the soil could present a health risk to communities should they decide to use the landfill site for arable purposes. / Environmental Sciences / M. Sc. (Environmental Science)
99

Environmental risk assessment associated with unregulated landfills in the Albert Luthuli Municipality, Mpumalanga Province, RSA

Mnisi, Fannie 31 August 2008 (has links)
Integrated management of municipal and hazardous waste is one of the challenges facing the new municipalities in South Africa, especially those located in previously disadvantaged rural areas. However, much of the research on solid and hazardous waste management in South Africa has examined waste management problematics in urban areas, the majority of which are located within the jurisdiction of local governments which are comparatively effective in terms of providing adequate disposal services. By contrast, this study has examined the environmental risk assessment associated with unregulated landfill sites in the Albert Luthuli municipality, in the Mpumalanga province. The determination of the environmental risk was achieved by the use of questionnaire surveys and landfill analysis forms in selected study areas. The findings have highlighted a very high environmental risk, nearly four times and above, the threshold limits set by the Department of Environmental Affairs and Tourism (DEAT, 2005:15) for all of the landfill sites examined. Several exposure pathways stemming from associated environmental impacts have also been identified for the study. The higher environmental risk determined for the problem sites is ascribed to numerous factors, including their ill-planned location, the sensitivity and vulnerability of the natural environment and adjacent rural settlements, the lack of appropriate waste pre-treatment processes prior to disposal, and most significantly, the lack of regulatory and control measures to contain the myriad of environmental problems generated. In conclusion, it is recommended that several measures (including closure) should be taken in order to reduce and contain the magnitude of environmental risks involved. / Environmental Sciences / M.Sc.(Environmental Sciences)
100

Environmental risk assessment associated with unregulated landfills in the Albert Luthuli Municipality, Mpumalanga Province, RSA

Mnisi, Fannie 31 August 2008 (has links)
Integrated management of municipal and hazardous waste is one of the challenges facing the new municipalities in South Africa, especially those located in previously disadvantaged rural areas. However, much of the research on solid and hazardous waste management in South Africa has examined waste management problematics in urban areas, the majority of which are located within the jurisdiction of local governments which are comparatively effective in terms of providing adequate disposal services. By contrast, this study has examined the environmental risk assessment associated with unregulated landfill sites in the Albert Luthuli municipality, in the Mpumalanga province. The determination of the environmental risk was achieved by the use of questionnaire surveys and landfill analysis forms in selected study areas. The findings have highlighted a very high environmental risk, nearly four times and above, the threshold limits set by the Department of Environmental Affairs and Tourism (DEAT, 2005:15) for all of the landfill sites examined. Several exposure pathways stemming from associated environmental impacts have also been identified for the study. The higher environmental risk determined for the problem sites is ascribed to numerous factors, including their ill-planned location, the sensitivity and vulnerability of the natural environment and adjacent rural settlements, the lack of appropriate waste pre-treatment processes prior to disposal, and most significantly, the lack of regulatory and control measures to contain the myriad of environmental problems generated. In conclusion, it is recommended that several measures (including closure) should be taken in order to reduce and contain the magnitude of environmental risks involved. / Environmental Sciences / M.Sc.(Environmental Sciences)

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