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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.
111

Implementation of a system for managing chemical waste in the laboratory of environmental sanitation of the UFC / ImplantaÃÃo de um sistema de gerenciamento de resÃduos quÃmicos no laboratÃrio de saneamento ambiental da UFC

DÃbora Scharamm Bezerra 22 August 2014 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / Despite Institutions Teaching and Research possess a fundamental role in the formation of its professionals, the lack of oversight and vision, along with the improper disposal of chemical waste, have led many laboratories and, consequently, many universities, polluting the environment, promote material waste and mismanagement perform its chemical waste liabilities and assets. Within this context, this work aims to propose a system for managing chemical waste generated at the Laboratory of Environmental Sanitation, Department of Hydraulic and Environmental Engineering, Federal University of CearÃ, with a focus on preventive actions to minimize waste, followed by their treatment. For this, the methodology consisted initially of completing the inventory of chemical waste liabilities followed by characterization of unidentified reagents, which are amenable to reuse. Based on a questionnaire, it was possible to know the main active chemical analyzes generating waste and the situation of how these waste materials were processed in the laboratory. These residues were analyzed for the presence of heavy metals and submitted the metal copper in waste from the analysis of NTK and silver, mercury and hexavalent chromium in the waste analysis of COD. Thus, treatments have been proposed for each metal, which were quantitated using the techniques of X-ray fluorescence and atomic absorption spectroscopy, flame. It was possible to characterize 85.71% of unidentified reagents and thus reuse of 58,125% of the Labosan passive chemical waste. Through the technique of atomic absorption spectroscopy, flame (FAAS), the residue of NKT analysis showed 100% removal of this cover, while the COD analysis of the residue showed removal of 99.984% 99.975% silver and chrome . Thus, it was observed that the final supernatants of chrome and copper treatments showed results within the limits established by CONAMA Resolution No. 430/2011. Through the technique of fluorescence (XRF) X-rays, it was found that solid precipitates of heavy metals showed high purities, such as silver which had purity of 99.223% and the mercury that had purity of 93.540%. Thus, the study supports the need to investigate further all waste generated in Labosan, as also with the implementation of a program of Chemical Waste Management in the UFC. / Apesar das InstituiÃÃes de Ensino e Pesquisa possuÃrem um papel fundamental na formaÃÃo de seus profissionais, a falta de fiscalizaÃÃo e de visÃo, juntamente com o descarte inadequado dos resÃduos quÃmicos, levaram muitos laboratÃrios e, consequentemente, muitas universidades, a poluir o meio ambiente, promover o desperdÃcio de material e realizar o mau gerenciamento dos seus resÃduos quÃmicos passivos e ativos. Dentro desse contexto, este trabalho objetiva propor um sistema de gerenciamento dos resÃduos quÃmicos gerados no LaboratÃrio de Saneamento Ambiental do Departamento de Engenharia HidrÃulica e Ambiental da Universidade Federal do CearÃ, com enfoque nas aÃÃes preventivas de minimizaÃÃo dos resÃduos, seguido do seu tratamento. Para isso, a metodologia constituiu-se inicialmente da realizaÃÃo do inventÃrio dos resÃduos quÃmicos passivos seguido da caracterizaÃÃo dos reagentes nÃo identificados, os quais sÃo passÃveis de reaproveitamento. Com base na aplicaÃÃo de um questionÃrio, foi possÃvel conhecer as principais anÃlises geradoras de resÃduos quÃmicos ativos e a situaÃÃo de como esses materiais residuais eram tratados no laboratÃrio. Esses resÃduos foram analisados quanto à presenÃa de metais pesados, tendo apresentado o metal cobre nos resÃduos provenientes da anÃlise de NTK e prata, mercÃrio e cromo hexavalente nos resÃduos da anÃlise de DQO. Assim, foram propostos tratamentos para cada metal, os quais foram quantificados utilizando as tÃcnicas de fluorescÃncia de raios-X e espectroscopia de absorÃÃo atÃmica de chama. Conseguiu-se a caracterizaÃÃo de 85,71% dos reagentes nÃo identificados e com isso a reutilizaÃÃo de 58,125% dos resÃduos quÃmicos passivos do Labosan. AtravÃs da tÃcnica de espectroscopia de absorÃÃo atÃmica de chama (FAAS), o resÃduo da anÃlise de NTK apresentou remoÃÃo de 100% do cobre presente, enquanto que o resÃduo da anÃlise de DQO apresentou remoÃÃo de 99,984% da prata e de 99,975% do cromo. Assim, foi observado que os sobrenadantes finais dos tratamentos do cromo e do cobre apresentaram resultados dentro dos limites estabelecidos pela ResoluÃÃo CONAMA n 430/2011. AtravÃs da tÃcnica de fluorescÃncia de raios-X (FRX), verificou-se que os sÃlidos precipitados dos metais pesados apresentaram elevadas purezas, como à o caso da prata que apresentou pureza de 99,223% e do mercÃrio que apresentou pureza de 93,540%. Assim, o estudo corrobora com a necessidade de investigar mais profundamente todos os resÃduos gerados no Labosan, como tambÃm com a implantaÃÃo de um Programa de Gerenciamento de ResÃduos QuÃmicos na UFC.
112

Estudo da aplicacao de biossorventes no tratamento de rejeitos radioativos liquidos contendo americio-241 / A study on application of biosorbents for treatment of radioactive liquid waste containing americium-241

BORBA, TANIA R. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:27:59Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:00:56Z (GMT). No. of bitstreams: 0 / O uso da energia nuclear para as mais diversas finalidades tem se intensificado e destacado pelos benefícios que proporciona. A medicina diagnóstica e terapêutica, a agricultura, a indústria, a geração de energia elétrica, são alguns exemplos. Entretanto, o uso da energia nuclear gera rejeitos radioativos e estes requerem tratamento adequado para garantir a segurança ambiental e dos seres vivos. A biossorção e bioacumulação representam uma alternativa emergente, para o tratamento de rejeitos radioativos líquidos, proporcionando redução de volume e mudança de estado físico. Este trabalho teve como objetivos estudar biossorventes para promover o tratamento de rejeitos líquidos contendo Amerício-241, proporcionando redução de volume e mudando seu estado físico para sólido. Os biossorventes avaliados foram: Saccharomyces cerevisiae imobilizadas em alginato de cálcio, Saccharomyces cerevisiae livres e inativadas, alginato de cálcio, Bacillus subtilis, Cupriavidus metallidurans e Ochrobactrum anthropi. Os resultados foram bastante satisfatórios, chegando a 100 % em alguns casos. Esta técnica parece viável para a implantação no Laboratório de Rejeitos Radioativos do IPEN - CNEN/SP a curto prazo, por ser simples e de baixo custo. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
113

Gestao de fontes radioativas seladas descartadas

VICENTE, ROBERTO 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:47:18Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:10:16Z (GMT). No. of bitstreams: 1 07974.pdf: 7652856 bytes, checksum: f4eff264fe7ae9ae4d05ffaefb1712a3 (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
114

Gestão e gerenciamento de resíduos químicos e aplicação da tecnologia de destilação na recuperação de solventes orgânicos: estudo de caso da reciclagem do xileno / Management and chemical waste management and application of distillation technique in organic solvent recovery: case analyze of xylene recovery

Juliana Cristina Levada 08 August 2008 (has links)
Este trabalho de pesquisa foi elaborado com o objetivo de apresentar os resultados da recuperação e reciclagem de xileno, gerado em laboratórios de análises clínicas. É importante salientar a importância de um programa de gestão e gerenciamento de resíduos químicos, principalmente em instituições de ensino e pesquisa, de forma a contribuir para a preservação do ambiente e possibilitar a formação de profissionais conscientes, acostumados à práticas corretas de gestão e gerenciamento de resíduos químicos. A recuperação do resíduos de xileno foi feita por meio da técnica de destilação fracionada. Para a verificação da eficiência da recuperação do xileno, foram analisadas amostras do resíduo de xileno, do xileno recuperado e do xileno padrão, com o propósito de comparar os resultados obtidos destas amostras por meio das análises de Espectrofotometria de ultravioleta visível, (UVVis), Refratometria, Cromatografia Gasosa (CG) e Cromatografia Gasosa acoplada à Espectrometria de Massas (CG-EM). Os resultados desta pesquisa confirmam a eficiência da recuperação do resíduo de xileno, possibilitando que este retorne ao processo produtivo ou gerador, na forma de produto, refazendo assim, o ciclo por completo. A recuperação do resíduo do xileno e sua reciclagem traz benefícios ambientais e econômicos. / This research was elaborated with the objectives to present the results of recovery and recycling of xylene, generated in clinical analyses laboratories. It is essential to point out the importance of management and chemical waste management program, especially in education and research institutions, contributing to environment preservation and to making possible the qualification of conscientious professionals, used with correct practices of management and the chemical waste management. The xylene waste was recovered by fractional distillation technique. To verify the efficiency of the xylene recovery it was analyzed samples of waste xylene, recovered xylene and standard xylene, to compare the obtained data of these samples through the ultraviolet-visible Spectrophotometry (UV - Vis), Refractometry, Gas Chromatography (GC) and connected Gas Chromatography to the Spectrometry of Mass (GC-MS) analyses. The results of this work confirmed the efficiency of the xylene recovery, making possible its return to the productive or generator processes as a product, thus completing the entire cycle. The recovery of the xylene waste and its recycling has important ambient and economic benefits.
115

Estudo da separação e aproveitamento da parte metálica e de óxidos presentes no resíduo gerado no corte de rochas ornamentais. / Study of separation and reuse of metallic part and present oxides in residue generated in ornamental rocks cutting.

Eduardo Junca 30 November 2009 (has links)
Este trabalho tem como objetivo o estudo do reaproveitamento da parte metálica e a caracterização dos óxidos presente no resíduo de granito gerado na etapa de desdobramento. Inicialmente, foi feita a caracterização química e física do resíduo através de análise química, difração de raios-X, microscopia eletrônica de varredura e análise granulométrica. Após a caracterização do resíduo, foi dado inicio aos processos para a recuperação do Fe metálico que envolveram: separação magnética, mesa concentradora e ciclonagem. A separação magnética foi realizada em três etapas: a primeira onde se utilizou um separador magnético a úmido de alta intensidade, onde foi utilizado apenas o campo magnético remanescente do equipamento. Na segunda etapa, onde o material magnético obtido na primeira etapa foi submetido a uma nova separação magnética manual utilizando um imã de terras raras. Na terceira etapa, o material magnético obtido com o imã de terras raras foi submetido a uma separação magnética manual com um imã ferrítico. Nos ensaios de mesa concentradora, foram realizadas variações na inclinação da mesa, freqüência de oscilação e vazão de água de lavagem. Já nos ensaios de ciclone, o parâmetro variado foi à pressão de alimentação. Foram realizadas variações nos parâmetros dos equipamentos com o intuito de se aperfeiçoar e definir os melhores parâmetros para a recuperação do Fe metálico. Após cada ensaio, foi realizada a análise química volumétrica para a determinação do teor de Fe metálico obtido em cada produto. Pelos resultados obtidos, o método de separação magnética foi a que apresentou os melhores resultados, sendo possível a obtenção de um concentrado ferroso com 93% de Fe metálico e um concentrado granítico com 0,6% de Fe metálico. Já nos ensaios de mesa concentradora, o melhor resultado obtido foi um concentrado ferroso com apenas 13,7% de Fe metálico, e nos ensaios de ciclone foi possível à obtenção de um produto com apenas 7,2% de Fe metálico. A partir do concentrado ferroso e granítico obtido na separação magnética foi realizada a caracterização através de microscopia eletrônica de varredura, difração de raios-X e análise granulométrica. A partir do concentrado ferroso obtido, foram produzidos briquetes com uso de 2% de cal hidratada como aglomerante. Foram realizados testes de resistência mecânica a verde e a seco nos briquetes produzidos. Foi obtido uma resistência mecânica a verde de no máximo 1,02 kN e a seco de no máximo 3,59 kN. / The aim of this work is to study the reuse of the metallic part and the characterization of oxides present in the waste from granite sawing. First, the chemical and physical characteristics of the waste were analyzed by chemical analysis, X-ray diffraction, scanning electron microscopy and size analysis. Procedures for the metallic iron recovery (magnetic separation, concentrator table, and cyclonic separation) were performed after the waste characterization. Magnetic separation was performed in three phases. First, using a high intensity wet magnetic separator, which only the remaining magnetic field of equipment was utilized. In the second phase, the magnetic material obtained in first phase was subjected to a new manual magnetic separation using rare earth magnets. In a third phase, magnetic material obtained with rare earth magnets was subjected to manual magnetic separation using ferrite magnets. In the experiments of concentrator table, were carried out changes in table inclination, oscillation frequency and wash water flow. For cyclone tests, the varied parameter was the water supply pressure. Variations in equipment parameters were performed in order to improve and decide the best parameters for recovery of metallic iron. After each experiment, volumetric chemical analysis was performed to determine the metallic iron content of each product. The results show that the magnetic separation method had the best results since it is possible to obtain a ferrous concentrated with 93.0 wt. % metallic iron and granite concentrated with 0.6 wt. % metallic iron. While for concentrator table tests, the best result presented a ferrous concentrated with only 13.6 wt. % metallic iron; and for cyclone tests, a product with only 7.2 wt. % of metallic iron was obtained. Ferrous and granite concentrated from magnetic separation were characterized by scanning electron microscopy, X-ray diffraction and size analysis. Using the obtained ferrous concentrated, briquettes were produced with 2 wt. % hydrated lime as binder. Produced briquettes were tested using dry and wet mechanical strength test. Wet mechanical strengths of up to 1.02kN were obtained, and a maximum of 3.59kN was registered to dry mechanical strength.
116

Re-defining the concepts of waste and waste management:evolving the Theory of Waste Management

Pongrácz, E. (Eva) 25 September 2002 (has links)
Abstract In an attempt to construct a new agenda for waste management, this thesis explores the importance of the definition of waste and its impact on waste management, and the role of ownership in waste management. It is recognised that present legal waste definitions are ambiguous and do not really give an insight into the concept of waste. Moreover, despite its explicit wish of waste prevention, when according to present legislation a thing is assigned the label of a waste, it is going to be treated like waste, implicitly legislation thus amasses waste. The philosophical ramifications inherent in such definitions mean that they are not capable of constructing a system that, by its very nature, results in a sustainable waste management system. It is also a fact that, while there are numerous practices as to how to deal with a particular type of waste, there is no theory of waste management. In this thesis, waste as a concept is analysed from the point of view of why and when waste is created. Using the PSSP language, waste is classified based on the Purpose and Performance attributes. New, dynamic definitions for waste and waste management are offered, which explain why waste is created and intrinsically offer a solution to how the problem could be solved. Additional waste-related concepts are introduced, which are thought to have great potential for improvement on waste regulation. The concept of ownership is explained as rights and responsibilities of waste creators/owners: it is thus crucial to raising awareness about waste. Ownership in itself often dictates which waste management options are preferentially adopted by a given community. The role of legislation in producing monitoring systems for the transfer of ownership as well as abandonment of ownership is analysed. To avoid obstacles to resource conservation due to materials being considered waste, a definition for non-waste is introduced. The new agenda for waste management thus focuses upon the development of more appropriate, sustainable definitions so that what is now commonly perceived as being waste will in fact be increasingly seen as resource-rich, 'non-waste'. The role of waste management is explained as control of all waste-related activities, with the aim of preventing, minimising or utilising waste. The need for a theory of waste management is explained, and the first building blocks of the theory are proposed. This thesis is offered as the first step toward scientification of waste management.
117

Vyhodnocení množství zpětně odebraných baterií a akumulátorů v rámci České republiky s využitím GIS / Quantity assessment of backward collected batteries and accumulators in the framework of the Czech Republic using GIS

Kukal, Tomáš Augustin January 2017 (has links)
The number of batteries and especially accumulators, which we use, is growing every time and collection with take-away is growing too. Now it is absolutelly important look for a way to optimalization, which can be for example builing new processing equipment. Graduation thesis deal with data analysis from battery collection, data processing and building a data model in four variants. Graduation thesis work with number of battery and accumulators in czech households and bring answer to question "How many batteries we have got approximately in our households?" Output is processing questionary about Research of battery in households,which is used in next work. The main output is data model.Model work with distance of take-way route on principe Service area and Transportation theory. Data are obtained by ArcGIS and processed in Excel. The output are map schematics which are based from four studies. First study shows present state, next shows battery factory in another capital town in regions of the Czech Republic. Third shows variant battery factories in three biggest cities and fourth battery factory in all czech cities, that have 100 000 residents. The best combinations is probably study with three biggest cities, because in this study is saving 50 % of costs and withal it is not necessary build many...
118

Posuzování životního cyklu skládkování odpadu / Life cycle assessment of landfilling

Kosová, Kristýna January 2017 (has links)
This thesis is focused on the method of Life Cycle Assessment (LCA) in Waste Management in the Czech Republic. The aim of this work is creation of landfill model and evaluate the main material, energy and elementary streams with influence on the environment. The output is an overview of each impact indicator, assessment most affected environmental categories by landfilling. and where is appropriate the optimization. The thesis consists of two parts, theoretical and experimental. The theoretical part deals generally about LCA, landfilling and municipal waste, their production and the possibilities of further handling them. In the experimental part is evaluated and compare the impact of 1 tonne lanfilling waste per 1 calendar year on several Czech landfills. The next was created average landfill model and its comparison with database models. Key words Landfill, Life Cycle Assessment, Waste Management, Municipal solid waste
119

Právní úprava odpadového hospodářství v České republice / Legal regulation of waste management in the Czech Republic

Huml, Miroslav January 2011 (has links)
English recapitulation of this thesis -Legal regulations of the Waste management in the Czech Republic The main purpose of the thesis is to demonstrate the most important waste management principles in the Czech Republic and in the other European countries. The thesis is divided into 8 chapters. The first chapter deals with a general introduction concerning the topic. It indicates global situation and undesirable influences of deficiencies in the waste management on condition of world seas and oceans. The second chapter considers the waste management as a branch of science activity. This branch was established in 1980s in west European countries, however, 10 years later also in the Czech Republic. The first Parliament Act on the waste management in Czechoslovakia was created in 1991. There were some mistakes and dubiousness in the Act and it was necessary to put them aside before joining the European Union in 2004. Before 2004, this Act had been changed completely two times. The Act of Czech Parliament 185/2001 Sb. went into force on 1st January 2002. Since then, it has been novelized many times according to the European law and is currently responding to the European directives. The third chapter mentions some other acts which are connected with the waste management in the Czech Republic. On the top of...
120

Understanding waste management behaviour in care settings in South West England : a mixed methods study

Manzi, Sean January 2015 (has links)
Introduction - Health and social care sector activities in the United Kingdom have a considerable carbon footprint which impacts on the natural environment. Waste management is one area of focus for the reduction of this environmental impact. Previous research has studied the quantities and compositions of healthcare waste highlighting the potential for recycling. Limited research to date has investigated both health and social care waste management in a holistic study incorporating the behaviour, composition and systems. The current study aimed to investigate waste management behaviour, systems and compositions at four health and social care sites in the South West of England, then derive a framework of health and social care waste management behaviour incorporating points of intervention for the improvement of waste management practices. Methods - A mixed methods multi-strategy concurrent triangulation design was used to investigate the waste management at four health and social care sites in the South West of England. This consisted of a management interview sub-study investigating waste management policy, guidance and training. An observational sub-study was used to investigate health and social care employee waste management behaviour. An audit of the clinical and domestic waste streams provided an overview of the waste composition at each site. Finally a self-report questionnaire sub-study of decision making was conducted to investigate the conscious and habitual aspects of waste management decision making. The findings from these four sub-studies were then synthesised through a data triangulation process. Findings - The domestic waste bins were most commonly used to dispose of waste during the observational sub-study. The waste audit sub-study found the domestic waste stream contained the largest percentage of potentially recyclable waste. The observational sub-study also uncovered twenty unique primary themes influencing the employee waste management behaviour. These themes included aspects internal to the health and social employee such as confusion, and external themes such as equipment. The management interviews highlighted a lack of waste management training and a reliance on the local site waste management policies to guide and monitor employee waste management behaviour. Discussion - The health and social care waste management behaviour improvement framework (HWMBIF) is presented. The HWMBIF is a novel framework, derived from the triangulated data of the current study, for understanding and improving waste management behaviour at the participating sites. Several interventions based in the HWMBIF and on the study findings are presented. Future research will focus on testing and refining the HWMBIF, the suggested interventions and developing further interventions.

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