969 resultados para Waste and nability


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The application of membrane separation processes (PSM) for treatment of radioactive waste requires the selection of a suitable membrane for the treatment of waste, as the membrane will be directly exposed to the radioactive liquid waste, and also exposed to ionizing radiation. The nanofiltration membrane is most suitable for treatment of radioactive waste, since it has high rejection of multivalent ions. Usually the membranes are made of polymers and depending on the composition of the waste, type and dose of radiation absorbed may be changes in the structure of the membrane, resulting in loss of its transport properties. We tested two commercial nanofiltration membranes: NF and SW Dow/Filmtec. The waste liquid used was obtained in the process of conversion of uranium hexafluoride gas to solid uranium dioxide, known as "carbonated water". The membranes were characterized as their transport properties (hydraulic permeability, permeate flux and salt rejection) before and after their immersion in the waste for 24 hours. The surface of the membranes was also evaluated by SEM and FTIR. It was observed that in both the porosity of the membrane selective layer was altered, but not the membrane surface charge, which is responsible for the selectivity of the membrane. The NF membranes and SW showed uranium ion rejection of 64% and 55% respectively.

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The relationship between industry, waste, and urbanism is one fraught with problems across the United States and in particular American cities. The interrelated nature of these systems of flows is in critical need of re-evaluation. This thesis critiques the system of Municipal Solid Waste Management as it currently exists in American cities as a necessary yet undesirable ‘invisible infrastructure’. Industry and waste environments have been pushed to the periphery of urban environments, severing the relationship between the urban environment we inhabit and the one that is required to support the way we live. The flow of garbage from cities of high density to landscapes of waste has created a model of valuing waste as a linear system that separates input from output. This thesis aims to investigate ways that industry, waste, and urban ecologies can work to reinforce one another. The goal of this thesis is to repair the physical and mental separation of waste and public activity through architecture. This thesis will propose ways to tie urban waste infrastructure and public amenities together through the merging of architecture and landscape to create new avenues for public engagement with waste processes.

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O objetivo deste estudo foi avaliar a inclusão de carne mecanicamente separada (CMS) (0, 20, 40, 60, 80 e 100%), obtido de resíduos de filetagem de tilápias do Nilo, em salsichas e determinar suas propriedades físico-químicas, nutricionais e sensoriais. As salsichas apresentaram diminuição de proteína e aumento de lipídeos com a inclusão de CMS. A qualidade nutricional dos produtos foi alta, com digestibilidade acima de 85%. Os parâmetros de textura e cor instrumental amarela (b*) diminuíram com inclusão crescente de CMS. A avaliação sensorial da cor mostrou que o nível máximo de inclusão de CMS não foi bem aceito pelos provadores. As salsichas com melhor aceitação do atributo sabor foram aquelas com 60% de CMS. Os resultados demonstraram a boa qualidade nutricional das salsichas utilizando CMS de resíduos de filetagem de tilápias do Nilo e de acordo com avaliação sensorial, a porcentagem máxima de inclusão é de 60%.

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In order to fulfil European and Portuguese legal requirements, adequate alternatives to traditional municipal waste landfilling must be found namely concerning organic wastes and others susceptible of valorisation. According to the Portuguese Standard NP 4486:2008, refuse derived fuels (RDF) classification is based on three main parameters: lower heating value (considered as an economic parameter), chlorine content (considered as a technical parameter) and mercury content (considered as an environmental parameter). The purpose of this study was to characterize the rejected streams resulting from the mechanical treatment of unsorted municipal solid waste, from the plastic municipal selective collection and from the composting process, in order to evaluate their potential as RDF. To accomplish this purpose six sampling campaigns were performed. Chemical characterization comprised the proximate analysis – moisture content, volatile matter, ashes and fixed carbon, as well as trace elements. Physical characterization was also done. To evaluate their potential as RDF, the following parameters established in the Portuguese standard were also evaluated: heating value and chlorine content. As expected, results show that the refused stream from mechanical treatment is rather different from the selective collection rejected stream and from the rejected from the compost screening in terms of moisture, energetic matter and ashes, as well as heating value and chlorine. Preliminary data allows us to conclude that studied materials have a very interesting potential to be used as RDF. In fact, the rejected from selective collection and the one from composting have a heating value not very different from coal. Therefore, an important key factor may be the blending of these materials with others of higher heating values, after pre-processing, in order to get fuel pellets with good consistency, storage and handling characteristics and, therefore, combustion behavior.

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In a globalized economy, the use of natural resources is determined by the demand of modern production and consumption systems, and by infrastructure development. Sustainable natural resource use will require good governance and management based on sound scientific information, data and indicators. There is a rich literature on natural resource management, yet the national and global scale and macro-economic policy making has been underrepresented. We provide an overview of the scholarly literature on multi-scale governance of natural resources, focusing on the information required by relevant actors from local to global scale. Global natural resource use is largely determined by national, regional, and local policies. We observe that in recent decades, the development of public policies of natural resource use has been fostered by an “inspiration cycle” between the research, policy and statistics community, fostering social learning. Effective natural resource policies require adequate monitoring tools, in particular indicators for the use of materials, energy, land, and water as well as waste and GHG emissions of national economies. We summarize the state-of-the-art of the application of accounting methods and data sources for national material flow accounts and indicators, including territorial and product-life-cycle based approaches. We show how accounts on natural resource use can inform the Sustainable Development Goals (SDGs) and argue that information on natural resource use, and in particular footprint indicators, will be indispensable for a consistent implementation of the SDGs. We recognize that improving the knowledge base for global natural resource use will require further institutional development including at national and international levels, for which we outline options.

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TESLA project (Transfering Energy Save Laid on Agroindustry) financed by the European Commission, had the main goals of evaluating the energy consumption and to identify the best available practices to improve energy efficiency in key agro-food sectors, such as the olive oil mills. A general analysis of energy consumptions allowed identifying the partition between electrical and thermal energy (approximately 50%) and the production processes responsible for the higher energy consumptions, as being the in the mill and paste preparation and the phases separation. Some measures for reducing energy waste and for improving energy efficiency were identified and the impact was evaluated by using the TESLA tool developed by Circe and available at the TESLA website.

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The increasing attention to environmental issues of recent times encourages us to find new methods for the production of energy from renewable sources, and to improve existing ones, increasing their energy yield. Most of the waste and agricultural residues, with a high content of lignin and non-hydrolysable polymers, cannot be effectively transformed into biofuels with existing technology. The purpose of the study was to develop a new thermochemical/ biological process (named Py-AD) for the valorization of scarcely biodegradable substances. A complete continuous prototype was design built and run for 1 year. This consists into a slow pyrolysis system coupled with two sequential digesters and showed to produce a clean pyrobiogas (a biogas with significant amount of C2-C3 hydrocarbons and residual CO/H2), biochar and bio-oil. Py-AD yielded 31.7% w/w biochar 32.5% w/w oil and 24.8% w/w pyrobiogas. The oil condensate obtained was fractionated in its aqueous and organic fraction (87% and 13% respectively). Subsequently, the anaerobic digestion of aqueous fraction was tested in a UASB reactor, for 180 days, in increasing organic loading rate (OLR). The maximum convertible concentration without undergoing instability phenomena and with complete degradation of pyrogenic chemicals was 1.25 gCOD L digester-1 d-1. The final yield of biomethane was equal to 40% of the theoretical yield and with a noticeable additional production equal to 20% of volatile fatty acids. The final results confirm that anaerobic digestion can be used as a useful tool for cleaning of slow pyrolysis products (both gas and condensable fraction) and the obtaining of relatively clean pyrobiogas that could be directly used in internal combustion engine.

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This thesis focuses on finding the optimum block cutting dimensions in terms of the environmental and economic factors by using a 3D algorithm for a limestone quarry in Foggia, Italy. The environmental concerns of quarrying operations are mainly: energy consumption, material waste, and pollution. The main economic concerns are the block recovery, the selling prices, and the production costs. Fractures adversely affect the block recovery ratio. With a fracture model, block production can be optimized. In this research, the waste volume produced by quarrying was minimised to increase the recovery ratio and ensure economic benefits. SlabCutOpt is a software developed at DICAM–University of Bologna for block cutting optimization which tests different cutting angles on the x-y-z planes to offer up alternative cutting methods. The program tests several block sizes and outputs the optimal result for each entry. By using SlabCutOpt, ten different block dimensions were analysed, the results indicated the maximum number of non-intersecting blocks for each dimension. After analysing the outputs, the block named number 1 with the dimensions ‘1mx1mx1m’ had the highest recovery ratio as 43% and the total Relative Money Value (RMV) with a value of 22829. Dimension number 1, also had the lowest waste volume, with a value of 3953.25 m3, for the total bench. For cutting the total bench volume of 6932.25m3, the diamond wire cutter had the lowest dust emission values for the block with the dimension ‘2mx2mx2m’, with a value of 24m3. When compared with the Eco-Label standards, block dimensions having surface area values lower than 15m2, were found to fit the natural resource waste criteria of the label, as the threshold required 25% of minimum recovery [1]. Due to the relativity of production costs, together with the Eco-Label threshold, the research recommends the selection of the blocks with a surface area value between 6m2 and 14m2.

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Development and characterization of biopolymers was done in AIJU’s laboratories. AIJU, Technological Institute for children’s products and leisure is based in Spain. The work has the aim to study qualities and characteristics of bioplastics’ blends, in order to design where improvements can be executed. Biopolymers represent a sector with great development possibilities because they combine high technical potential and eco-sustainability. Nowadays, plastic pollution has becoming increasingly concerning, particularly in terms of management of waste. Bioplastics provide an alternative for the disposal of products, reducing the volume of waste and enhancing the end of life recovery. Despite the growing interest in biopolymers there is some gaps that need be filled. The main objective on this work, is the optimization of bioplastics mechanical properties, to find suitable substitutes, as similar as possible to conventional plastics. Firstly, investigations on processability of biomaterials has been deepen since the project deals with toy manufacturing’s sector. Thus, starting from laboratory scale the work aspires to expand industrially. By working with traditional machines, it was notable that, with some limited modifications, the equipment can perform the same functions. Therefore, operational processes do not emerge as an obstacle to the production chain. Secondly, after processing bio-blends, they are characterized by thermal tests (melt flow index, differential scanning calorimetry-DSC, thermogravimetry-TGA) and mechanical tests (traction and flexural tests, Charpy impact, SHORE D hardness and density). While the compatibility does not show relevant results, mechanical improvements has been visualized with addition of more ductile materials. The study was developed by inclusion of sustainable additive VINNEX® to blends. The thesis has highlighted that integration of more flexible materials provides elasticity without compromising bioplastics’ properties.

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This doctoral dissertation represents a cluster of research activities carried out at the DICAM Department of the University of Bologna during a three-year Ph.D. course. The goal of this research is to show how the development of an interconnected infrastructure network, aimed at promoting accessibility and sustainability of places, is fundamental in a framework of deep urban regeneration. Sustainable urban mobility plays an important role in improving the quality of life of citizens. From an environmental point of view, a sustainable mobility system means reducing fuel discharges and energy waste and, in general, aims to promote low carbon emissions. At the same time, a socially and economically sustainable mobility system should be accessible to everybody and create more job opportunities through better connectivity and mobility. Environmentally friendly means of transport such as non-motorized transport, electric vehicles, and hybrid vehicles play an important role in achieving sustainability but require a planned approach at the local policy level. The aim of this study is to demonstrate that, through a targeted reconnection of road and cycle-pedestrian routes, the quality of life of an urban area subject to degradation can be significantly improved just by increasing its accessibility and sustainability. Starting from a detailed study of the European policies and from the comparison with real similar cases, the case study of the Canal Port of Rimini (Italy) has been analysed within the European project FRAMESPORT. The analysis allowed the elaboration of a multicriterial methodology to get to the definition of a project proposal and of a priority scale of interventions. The applied methodology is a valuable tool that may be used in the future in similar urban contexts. Finally, the whole project was represented by using virtual reality to visually show the difference between the before and after the regeneration intervention.

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Plastic is an essential asset for the modern lifestyle, given its superiority as a material from the points of view of cost, processability and functional properties. However, plastic-related environmental pollution has become nowadays a very significant problem that can no longer be overlooked. For this reason, in recent decades, the research for new materials that could replace fossil fuel-based plastics has been focused on biopolymers with similar physicochemical properties to fossil fuel-based plastics, such as Polyhydroxyalkanoates (PHA). PHAs are a family of biodegradable polyesters synthesized by many microorganisms as carbon and energy reserves. PHA appears as a good candidate to substitute conventional petroleum-based plastics since it has similar properties, but with the advantage of being biobased and biodegradable, and has a wide range of applications (e.g., packaging). However, the PHA production cost is almost four times higher (€5/kg) than conventional plastic manufacturing. The PHA production by mixed microbial cultures (MMC) allows to reduce production costs as it does not require aseptic conditions and it enables the use of inexpensive by-products or waste streams as these cultures are more amenable to deal with complex feedstocks. Saline wastewaters (WWs), generated by several industries such as seafood, leather and dairy, are often rich in organic compounds and, due to a strong salt inhibition, the biological treatments are inefficient, and their disposal is expensive. These saline WWs are a potential feedstock for PHA production, as they are an inexpensive raw material. Moreover, saline WWs could allow the utilization of seawater in the process as dilution and cleaning agent, further decreasing the operational costs and the environmental burden of the process. The main goal of the current project is to assess and optimize the PHA production from a mixture of food waste and brine wastewater from the fishery industry by MMC.

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Furfural and its derivatives represent renewable and readily available platforms for a wide range of chemicals. Much attention has been devoted to their functionalization over the last years. TM-catalysed C–H activation has emerged as a powerful tool for synthesizing new C–C and C–X bonds. Moreover, it provides a sustainable way to obtain molecules by reducing waste and saving steps. At the same time, iridium catalysts have proven to be very active in some C–H functionalizations of several (hetero)arenes. Although very promising, this technique is still poorly applied on an industrial scale due to the severe conditions required. Continuous flow chemistry using heterogeneous catalysts appears to be a valuable way to overcome these problems. In this work, we present different solutions for the immobilization of homogeneous iridium complexes on silica gels, using bidentate amines and phosphines as anchoring ligands. We successfully employed the catalysts in C–H silylation and borylation of furfural, using C2 located directing group. In this way, we finally obtained a suitable catalyst that could be potentially applied in continuous-flow chemistry.

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Atualmente, o aproveitamento de resíduos na construção civil tem sido estimulado, uma vez que esse setor apresenta-se como um dos maiores consumidores de materiais naturais em seus processos e produtos. As cinzas ocupam lugar de destaque entre os resíduos agroindustriais por resultarem de processos de geração de energia. Grande parte dessas cinzas possui atividade pozolânica, podendo ser utilizada como substituto parcial do cimento Portland, resultando numa economia significativa de energia e custo. Este trabalho faz parte de uma pesquisa mais ampla, a qual busca avaliar a viabilidade técnica da cinza da casca da castanha de caju (CCCC) como adição mineral em matrizes de cimento Portland, como também, propor uma metodologia de análise de cinzas agroindustriais. Aplicou-se a técnica de difratometria de raios X para avaliar a reatividade do hidróxido de cálcio pela cinza da casca da castanha de caju em pastas, empregaram-se teores de substituição entre 2,5 e 30,0% e os difratogramas das pastas foram comparados com os das pastas confeccionadas com sílica ativa, executados sobre as mesmas condições de ensaio. Os resultados apontam para a ausência de reatividade pozolânica da CCCC com o cimento Portland.

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Purposes: To evaluate the dosimetric effect of outpatient radioiodine therapy for thyroid cancer in members of a patient`s family and their living environment, when using iodine-131 doses reaching 7.4 GBq. The following parameters were thus defined: (a) whole-body radiation doses to caregivers, (b) the production of contaminated solid waste, and (c) radiation potential and surface contamination within patients` living quarters. Methods: In total, 100 patients were treated on an outpatient basis, taking into consideration their acceptable living conditions, interests, and willingness to comply with medical and radiation safety guidelines. Both the caregivers and the radiation dose potentiality inside patients` residences were monitored by using thermoluminescent dosimeters. Surface contamination and contaminated solid wastes were identified and measured with a Geiger-Muller detector. Results: A total of 90 monitored individuals received a mean dose of 0.27 (+/- 0.28) mSv, and the maximum dose registered was 1.6 mSv. The mean value for the potential dose within all living quarters was 0.31(+/- 0.34) mSv, and the mean value per monitored surface was 5.58 Bq/cm(2) for all the 1659 points measured. The overall production of contaminated solid wastes was at a low level, being about 3 times less than the exemption level indicated by the International Atomic Energy Agency. Conclusions: This study indicates that the treatment of thyroid cancer by applying radioiodine activities up to 7.4 GBq, on an outpatient basis, is a safe procedure, especially when supervised by qualified professionals. This alternative therapy should be a topic for careful discussion considering the high potential for reducing costs in healthcare and improving patient acceptance.