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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.
141

Gestão de resíduos sólidos e aspectos do cooperativismo no município de Bauru - SP /

Santos, Richard Apolonio. January 2016 (has links)
Orientador: Rosane Aparecida Gomes Battistelle / Banca: Barbara Stolte Bezerra / Banca: Aloisio Costa Sampaio / Resumo: Este trabalho tem por objetivo avaliar a gestão de cooperativas de recicláveis no município de Bauru, utilizando como base os estudos já existentes e as problemáticas levantadas em visitas técnicas. Foram realizados o levantamento bibliográfico e documental, além de consultas às diversas entidades e organismos não governamentais, para, assim, realizar mapeamento comparativo das informações. A metodologia utilizada foi o estudo de caso com abordagens tanto quantitativas, quanto qualitativas, dependendo dos dados a serem tratados e apresentados. Este trabalho traça o perfil das cooperativas de reciclagem e dos catadores de material reciclável no município de Bauru. E, como proposição de melhorias nos processos das cooperativas, apontando as causas das problemáticas encontradas durante os estudos, foram listadas diversas ações ligadas à gestão pública e da própria cooperativa. / Abstract: This study has since objective values the management of cooperatives of recycling at the local authority of Bauru, using like base the already existent studies and the problems lifted in technical visits. They were carried out the bibliographical and documentary lifting, besides consultations to several entities and organisms not government, so, to carry out mapping comparatively of the informations. The used methodology was the case study with approaches so much quantitative, how much qualitative, depending on the data being treated and presented. This work draws the profile of the cooperatives of recycling and of the collectors of material recycling in the local authority of Bauru. And, like improvements proposition in the processes of the cooperatives, pointing to the causes of the problems found during the studies, there were listed several actions connected with the public management and of the cooperative itself. / Mestre
142

Concreto permeável com agregados reciclados de resíduos de isoladores elétricos de porcelana

Ribeiro, Aline 28 October 2014 (has links)
A geração de resíduos, em geral, pode trazer diversos problemas ao meio ambiente em decorrência de seu descarte inadequado, tornando necessária a busca por métodos alternativos para o manuseio, tratamento e disposição final dos mesmos. A Política Nacional Brasileira de Resíduos Sólidos de 2010 estabelece que os resíduos sólidos gerados em território brasileiro, de qualquer natureza, devem ser, nos processos geradores, reduzidos, tratados e reutilizados dentro do conceito de desenvolvimento sustentável. Estima-se que o Brasil produza, anualmente, 30.000 toneladas de isoladores elétricos de porcelana para abastecer sua rede elétrica, com uma geração de resíduos da ordem de 10% do total produzido. Diante deste cenário, a busca por alternativas para utilização de resíduos de isoladores elétricos de porcelana em novos produtos, tem despertado o interesse acadêmico e tecnológico. Neste estudo, resíduos de isoladores elétricos de porcelana (RIP) foram cominuídos em dimensões compatíveis para a aplicação em concretos permeáveis e foram caracterizados por análise física (granulométrica, índice de forma, absorção de água, massa específica). A partir da caracterização do RIP, foi proposta uma matriz experimental para a avaliação de concretos permeáveis, incorporando 50 e 100% em massa de RIP em substituição aos agregados graúdos. As propriedades de resistência mecânica sob compressão, sob tração na flexão, e o módulo de elasticidade das proporções com essas incorporações foram comparadas às de um concreto referência. Os resultados de resistência mecânica sob compressão para os concretos permeáveis propostos foram inferiores ao referência 21, e 24% respectivamente para 50 e 100% em massa de RIP, sob tração na flexão os resultados foram inferiores 38 e 46,5% respectivamente para 50 e 100% em massa de RIP, o módulo de elasticidade foi inferior ao referência 6,4% respectivamente para 50% em massa de RIP e superior 3,13% respectivamente para 100% em massa de RIP. Os resultados de resistência mecânica sob compressão, sob tração na flexão e o módulo de elasticidade para os concretos permeáveis 50 e 100% em massa de RIP encontram-se dentro dos valores relatados na literatura para concretos permeáveis. Os resultados de índice de vazios dos concretos permeáveis, referência, 50% em massa de RIP e 100% em massa de RIP ficaram numa faixa de 12,5 – 18,2% e os resultados do coeficiente de permeabilidade para os concretos permeáveis referência, 50% em massa de RIP e 100% em massa de RIP ficaram numa faixa de 0,05 a 0,2 cm∙s-1 na condição amostra seca e 0,14 a 0,15 cm∙s-1 na condição amostra saturada, contudo encontram-se dentro dos valores relatados na literatura para concretos permeáveis. Os resultados demonstram que é possível utilizar resíduos de isoladores elétricos de porcelana em substituição a agregados graúdos, permitindo incorporações de até 100% de RIP em concreto permeável. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-02-23T18:35:29Z No. of bitstreams: 1 Dissertacao Aline Ribeiro.pdf: 164454 bytes, checksum: 33cde29e9f0898b83a87c5641d09b037 (MD5) / Made available in DSpace on 2015-02-23T18:35:29Z (GMT). No. of bitstreams: 1 Dissertacao Aline Ribeiro.pdf: 164454 bytes, checksum: 33cde29e9f0898b83a87c5641d09b037 (MD5) / Companhia Paulista de Força e Luz / The generation of waste, in general, can bring many environment issues due to their improper disposal, making necessary to search for alternative methods for handling, treatment and final disposal of them. The Brazilian National Solid Waste Policy of 2010 defines that the solid waste generated in Brazilian territory, of any kind, should be, in their generators processes, reduced, treated and reused within the concept of sustainable development. It is estimated that Brazil produces annually 30,000 tons of electrical porcelain insulators to supply its power grid with a waste generation around 10% of the total production. In this scenario, the search for alternatives to the use of waste electrical porcelain insulators on new products has attracted academic and technological interest. In this study, waste electrical porcelain insulators (RIP) were comminuted in sizes compatible for use in permeable concrete. They were characterized by physical analysis (particle size distribution, shape index, water absorption and specific mass). Based on the characterization of RIP, an experimental matrix was proposed, to evaluate permeable concrete by incorporating 50 to 100%wt of RIP instead of coarse aggregate. The mechanical strength properties under compression, tension in bending and the modulus of elasticity of aforementioned proportions were compared to a reference concrete. The results of mechanical strength under compression for the proposed permeable concrete showed lower values than for the reference (values of 21 and 24% for 50 and 100 %wt of RIP, respectively). In tension in bending, the results were 38 and 46.5 % lower for 50 and 100%wt of RIP, respectively. The modulus of elasticity of the proportion 50%wt of RIP was 6.4% lower than the reference, while for the proportion 100%wt of RIP was 3.13% higher than the reference. The results of mechanical strength under compressive tensile, bending and the modulus of elasticity for the specific permeable concrete are within the reported values in the literature for this kind of material. The void index results for the permeable concrete and the reference were in a range from 12.5 to 18.2% and the results of the permeability coefficient were in a range of 0.05 to 0.2 cm s-1 in the sample dry condition and of 0.14 to 0.15 cm s-1 in the sample saturated condition, however they lie within the literature reported values for permeable concrete. The results demonstrate that it is possible to use waste electrical porcelain insulators replacing coarse aggregate, enabling the incorporation of up to 100% of RIP in permeable concrete.
143

An evaluation of solid waste management with specific reference to the municipality of Maputo City (Mozambique)

Manhica, Elsa Alberto Pondja January 2012 (has links)
Thesis (MTech (Public Management))--Cape Peninsula University of Technology, 2012. / One of the greatest problems Mozambique is currently facing is the increased involvement of sectors in producing large amounts of solid waste on a daily basis. These sectors are involved in activities that take place in homes, industry, mining, agriculture and commerce. As a result, this problem needs to be treated efficiently by the Municipality of Maputo. Solid waste produced each day in Maputo is not only an aesthetic problem but poses a threat to citizens' health and it damages the environment. With the production of large amounts of waste each day, the Municipality of Maputo is faced with an ineffective solid waste management system. This ineffectiveness is due to a number of reasons, which include lack of resources, inadequate or no staff training, poor management of solid waste by both the municipal and the government, inappropriate laws to regulate solid waste collection, poor control of such laws in terms of removal and disposal of the waste, using past colonial methods for dealing with solid waste and poor community involvement, The problem not only affects the Municipality of Maputo but it also affects both citizens and the environment. Ineffective solid waste management is linked to poor management, lack of resources, poor staff training, and unskilled public officials. The city gets dirtier as the amount of waste increases day by day, due to the fact that citizens living in rural areas have immigrated to the city looking for work after the civil war, which took place between 1977 and 1994. Emerging from a severely damaged war-torn economy, Mozambique is still in the process of reconstituting many of its public institutions. Communities, local government, industry, commerce, civil society, academics and religious organisations can no longer turn a blind eye to poor solid waste management. Instead, they need to join to fight against poor management of solid waste. The current situation demonstrates that too few individuals, non-profit organisations and private companies are involved in solid waste management activities. Effective solid waste management can only be effective if it engages all producers of waste and captures the policy strategies, planning and challenges of sustainable development.
144

Investigation of some scale-up conditions on the synthesis of faujasite zeolites from South African coal fly ash

Brassell, James Philip January 2017 (has links)
Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2017. / Coal fly ash waste produced from the coal combustion process is becoming an ever increasing concern. It is produced in such abundance due to not only South Africa, but the whole of the world relying mainly on coal combustion for the main source of energy production. With the growing rate of the human population this energy production is ever increasing. The current methods of disposal of this fly ash is not sustainable, it is being dumped in ash dumps, and poses a risk to the surrounding environment and human population. Therefore, processes need to be developed to take this waste and turn it into useful materials. This would not only solve the problem of its disposal but also create useful products that can be applied to further protect the environment. It was discovered that one of the useful materials that can be synthesised from fly ash are zeolites. These nano-porous structures have a wide variety of uses. Therefore, many studies have been conducted around optimising the synthesis of various zeolites from coal fly ash. More recently these studies have focused on the scale-up conditions needed to synthesise these zeolites on the large industrial scale, regarding the sheer volume of fly ash produced annually. The most robust and widely used technique for zeolite synthesis involves a pre-synthesis fusion of the fly ash with sodium hydroxide at a temperature of 550 0C. This would not be feasible to scale-up to industrial scale because of the energy intensity. Therefore, alternative pre-synthesis techniques have been proposed. One of those techniques involves using a sonochemical treatment as a pre-synthesis. It can be argued that this technique may not be able to be easily scaled. To solve this problem, another alternative technique was investigated within this study. It involves the use of a jet loop pilot plant mixing system, which can be scaled-up very readily to industrial scale.
145

Concreto permeável com agregados reciclados de resíduos de isoladores elétricos de porcelana

Ribeiro, Aline 28 October 2014 (has links)
A geração de resíduos, em geral, pode trazer diversos problemas ao meio ambiente em decorrência de seu descarte inadequado, tornando necessária a busca por métodos alternativos para o manuseio, tratamento e disposição final dos mesmos. A Política Nacional Brasileira de Resíduos Sólidos de 2010 estabelece que os resíduos sólidos gerados em território brasileiro, de qualquer natureza, devem ser, nos processos geradores, reduzidos, tratados e reutilizados dentro do conceito de desenvolvimento sustentável. Estima-se que o Brasil produza, anualmente, 30.000 toneladas de isoladores elétricos de porcelana para abastecer sua rede elétrica, com uma geração de resíduos da ordem de 10% do total produzido. Diante deste cenário, a busca por alternativas para utilização de resíduos de isoladores elétricos de porcelana em novos produtos, tem despertado o interesse acadêmico e tecnológico. Neste estudo, resíduos de isoladores elétricos de porcelana (RIP) foram cominuídos em dimensões compatíveis para a aplicação em concretos permeáveis e foram caracterizados por análise física (granulométrica, índice de forma, absorção de água, massa específica). A partir da caracterização do RIP, foi proposta uma matriz experimental para a avaliação de concretos permeáveis, incorporando 50 e 100% em massa de RIP em substituição aos agregados graúdos. As propriedades de resistência mecânica sob compressão, sob tração na flexão, e o módulo de elasticidade das proporções com essas incorporações foram comparadas às de um concreto referência. Os resultados de resistência mecânica sob compressão para os concretos permeáveis propostos foram inferiores ao referência 21, e 24% respectivamente para 50 e 100% em massa de RIP, sob tração na flexão os resultados foram inferiores 38 e 46,5% respectivamente para 50 e 100% em massa de RIP, o módulo de elasticidade foi inferior ao referência 6,4% respectivamente para 50% em massa de RIP e superior 3,13% respectivamente para 100% em massa de RIP. Os resultados de resistência mecânica sob compressão, sob tração na flexão e o módulo de elasticidade para os concretos permeáveis 50 e 100% em massa de RIP encontram-se dentro dos valores relatados na literatura para concretos permeáveis. Os resultados de índice de vazios dos concretos permeáveis, referência, 50% em massa de RIP e 100% em massa de RIP ficaram numa faixa de 12,5 – 18,2% e os resultados do coeficiente de permeabilidade para os concretos permeáveis referência, 50% em massa de RIP e 100% em massa de RIP ficaram numa faixa de 0,05 a 0,2 cm∙s-1 na condição amostra seca e 0,14 a 0,15 cm∙s-1 na condição amostra saturada, contudo encontram-se dentro dos valores relatados na literatura para concretos permeáveis. Os resultados demonstram que é possível utilizar resíduos de isoladores elétricos de porcelana em substituição a agregados graúdos, permitindo incorporações de até 100% de RIP em concreto permeável. / Companhia Paulista de Força e Luz / The generation of waste, in general, can bring many environment issues due to their improper disposal, making necessary to search for alternative methods for handling, treatment and final disposal of them. The Brazilian National Solid Waste Policy of 2010 defines that the solid waste generated in Brazilian territory, of any kind, should be, in their generators processes, reduced, treated and reused within the concept of sustainable development. It is estimated that Brazil produces annually 30,000 tons of electrical porcelain insulators to supply its power grid with a waste generation around 10% of the total production. In this scenario, the search for alternatives to the use of waste electrical porcelain insulators on new products has attracted academic and technological interest. In this study, waste electrical porcelain insulators (RIP) were comminuted in sizes compatible for use in permeable concrete. They were characterized by physical analysis (particle size distribution, shape index, water absorption and specific mass). Based on the characterization of RIP, an experimental matrix was proposed, to evaluate permeable concrete by incorporating 50 to 100%wt of RIP instead of coarse aggregate. The mechanical strength properties under compression, tension in bending and the modulus of elasticity of aforementioned proportions were compared to a reference concrete. The results of mechanical strength under compression for the proposed permeable concrete showed lower values than for the reference (values of 21 and 24% for 50 and 100 %wt of RIP, respectively). In tension in bending, the results were 38 and 46.5 % lower for 50 and 100%wt of RIP, respectively. The modulus of elasticity of the proportion 50%wt of RIP was 6.4% lower than the reference, while for the proportion 100%wt of RIP was 3.13% higher than the reference. The results of mechanical strength under compressive tensile, bending and the modulus of elasticity for the specific permeable concrete are within the reported values in the literature for this kind of material. The void index results for the permeable concrete and the reference were in a range from 12.5 to 18.2% and the results of the permeability coefficient were in a range of 0.05 to 0.2 cm s-1 in the sample dry condition and of 0.14 to 0.15 cm s-1 in the sample saturated condition, however they lie within the literature reported values for permeable concrete. The results demonstrate that it is possible to use waste electrical porcelain insulators replacing coarse aggregate, enabling the incorporation of up to 100% of RIP in permeable concrete.
146

An economic evaluation of waste telecommunication cable disposal in South Africa : a case study

Lottering, Tony January 2008 (has links)
South African manufacturers, including those who produce electrical and telecommunication cables, are required by the National Waste Management Strategy (NWMS) (drawn up by the Department of Environmental Affairs and Tourism (DEAT)), to carry out waste management in a coordinated and controlled manner. It is also becoming more difficult for South African companies, who produce for export markets, to conduct business internationally if they do not have some form of environmental management system in place. While there will always be scrap generated in any manufacturing environment, the aim is, first and foremost, to reduce this to acceptable levels and, secondly, to dispose of all scrap produced in a socially responsible manner. This study focuses attention on waste management, in the form of recycling, in the cable manufacturing industry. The purpose of this study is twofold: first, to examine the economic case, by means of a cost-benefit analysis, for the establishment and operation of a telecommunication cable waste recycling plant for the purpose of recycling copper conductor; second, to examine the economic feasibility, by means of a cost-benefit analysis, of extending the existing facility in order to accommodate the recycling of the plastic fraction contained in the cable waste. A specific cost-benefit stream was generated over a project period of 20 years for both CBAs. In both CBAs costs and benefits were categorised as being either primary or secondary. The primary costs and benefits for both CBAs were all financial in nature and were valued using market prices. The secondary costs of establishing and operating a cable waste recycling plant for recycling the copper conductor included effluent costs and noise pollution costs. The secondary benefits, on the other hand, included the creation of downstream industries. The secondary costs of extending an existing cable waste recycling plant, so as to accommodate the recycling of the plastic component of cable waste, included costs related to the generation of greenhouse gases and asthma. The secondary benefits, conversely, included the increase in house prices due to the reduction of landfilling of the plastic component of cable waste. The determination of increased house prices due to landfill avoidance was carried out using the hedonic pricing method (HPM). The hypothesis was that house values would increase the further removed they were from the landfill site. Applying regression analysis to the derived hedonic pricing (HP) function showed that there is a definite correlation between the two. Properties positioned two kilometres from a landfill site in New Brighton Port Elizabeth, Eastern Cape, were found to have higher values than those positioned adjacent to the site. From the cost-benefit streams, net benefits were calculated for each CBA and discounted to present values in order to provide a standard of comparison. The social discount rate used in this study to calculate the present values reflected a combination of the social opportunity costs of capital and the social time preference rate. The rate used was calculated as the average annual rate between 2000 and 2005 and amounted to 6.72 percent. It was derived from a combination of the opportunity costs of government borrowings, household consumption borrowings and return on savings.
147

City of Denton Municipal Solid Waste Characterization and Management Strategies

Brady, Patricia D. 05 1900 (has links)
Due to concern about diminishing landfill space, the City of Denton contracted a municipal solid waste characterization study in 1999 that would identify materials for diversion. This paper describes the results of 5 1-week waste sorting events, a scale-house analysis, a recycling participation study, a recycler profile and a similar city study. The results of the characterization studies suggest that at least 50% of each waste stream is recyclable or divertible though paper products accounted for no more than 45% by weight of any waste stream. Curbside recycling participation rate was 71% during the 6-week study period though the average weekly set-out rate was 37%. Recycling participation rates varied significantly by zip code and by home value categories but not by gender. Denton is fairly progressive in its waste management approach when compared to demographically similar cities on a 15-question assessment though recommendations for improvement have been identified.
148

Challenges in recycling used cooking oil to produce biodiesel in Polokwane

Ramuedzisi, Humbelani Elson January 2016 (has links)
Thesis submitted in 50 % completion of the degree of Master of Management in the field of Public and Development Management at the University of the Witwatersrand, Johannesburg. 20 June 2016 / In response to the ever increasing problems associated with climate change, and greenhouse gas emissions, many countries in the world are developing and adopting climate change resilient policies that support green economy. Green economy sector in South Africa has not as yet received much expected attention as a key sector to address economic and environmental problems. The use and the production of renewable fuels, such as biodiesel are known to have significant economic and environmental benefits. However, progress in the production of biodiesel is hampered by limits imposed by government on the use of fresh vegetable extracted oils for production of biodiesel, mainly due to challenges on food security; and the impact this will have on food prices. In recent years recycling has become an important tool to address waste problems; pollution control; and socio-economic problems such as joblessness, poverty and social inequity. Used cooking oil has always been considered waste and an environmental burden. Therefore through technology advancement of recycling, wastes such as used cooking oil have become useful resources for biodiesel production. This research is about the challenges in recycling used cooking oil to produce biodiesel. The study recommended that in order to address challenges facing sustainability of our environment, and high unemployment rate; small recycling industries such as those operating in Polokwane will need government support such as biodiesel sector policies and regulations, to encourage investment in the biodiesel value chains in a way that will lead to the achievement of green economy goals. / MT2016
149

Collecting recyclables at corporate sites: attempts to increase employee participation

Randall, Kim D. 24 October 2009 (has links)
The primary purpose of this study was to determine the efficacy of corporate-based recycling for communities without access to curb-side pick up of recyclable material. The secondary purpose was to use the taxonomy of behavior change strategies as devised by Geller et al. (1990a, b). The hypotheses of the study were as follows: 1) corporate-based recycling is an effective means of dealing with residential waste management in a rural community, 2) the effectiveness of one behavior change technique with a score of three (as proposed in the Taxonomy of Behavior Change Techniques) will be the same as an intervention package comprised of several techniques with a score of three, 3) the smaller the company, the more effective the intervention package and, 4) salaried employees will deposit more recyclable materials per person at the drop-off site than wage employees. Recycling drop off sites were established at the work place of rural residents as an alternative to curb-side pick up of recyclable material. Three sites chosen were located in a rural community in Southwestern Virginia. Two of the companies produced machine parts (n= 220, n=300). The third company produced printed material (n=32). Each company had both male and female wage and salaried employees with varying ages and levels of income. Recyclable materials (clear glass, green glass, brown glass and aluminum cans) were collected in four 33 gallon barrels in the parking lot of each company every Friday and weighed at the county collection center. In an attempt to motivate participation in the recycling program, the employees were informed of the availability of the barrels, given written prompts in the form of paycheck inserts and posters, and given group feedback in the form of a poster showing the weekly amount of each material collected at an individual company. One company also received a group meeting to promote consensus and to determine the weakness of the project. All prompts and feedback were given as a package at discrete periods of time in a multiple baseline design by groups. The intervention package was given twice at one site to determine the impact of repeated exposure to the intervention materials. Findings of the study indicated an erratic pattern of participation across the three sites. One site had such low participation that it was dropped from the study. The intervention packages did not significantly increase participation and the differences between wage and salaried employees were insignificant. It must be concluded that while some employees did participate in the recycling program refinements to both the interventions and the measurement techniques are needed. Directions for future research on the feasibility of corporate-based are discussed. / Master of Science
150

Resource recovery development: factors affecting decisions

Black, Linda January 1987 (has links)
Municipalities are increasingly facing solid waste disposal problems due to lack of sanitary landfill sites, high costs of landfill management and increasingly stringent environmental standards. Consequently, they are turning toward innovative disposal practices to alleviate these problems. However, very little comprehensive information is available to decision makers on the range of options available in resource recovery development and the factors that can influence choices. This thesis tests the hypothesis that there are a definable set of factors or circumstances that have led resource recovery developers to make specific decisions regarding ownership, operation, financing, system technology, and air pollution control technology. The thesis is divided into three stages: development of case studies on 9 resource recovery facilities in the state of Virginia; development and analysis of a nationwide survey to test the patterns illustrated in these case studies; and finally, the development of a guide for resource recovery developers that will serve as preliminary guidance in their choice of development options. / M. Arch.

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