994 resultados para Urbanization - industrial recycling


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This paper revisits work on the socio-political amplification of risk, which predicts that those living in developing countries are exposed to greater risk than residents of developed nations. This prediction contrasts with the neoliberal expectation that market driven improvements in working conditions within industrialising/developing nations will lead to global convergence of hazard exposure levels. It also contradicts the assumption of risk society theorists that there will be an ubiquitous increase in risk exposure across the globe, which will primarily affect technically more advanced countries. Reviewing qualitative evidence on the impact of structural adjustment reforms in industrialising countries, the export of waste and hazardous waste recycling to these countries and new patterns of domestic industrialisation, the paper suggests that workers in industrialising countries continue to face far greater levels of hazard exposure than those of developed countries. This view is confirmed when a data set including 105 major multi-fatality industrial disasters from 1971 to 2000 is examined. The paper concludes that there is empirical support for the predictions of socio-political amplification of risk theory, which finds clear expression in the data in a consistent pattern of significantly greater fatality rates per industrial incident in industrialising/developing countries.

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Heavy metal pollution is a matter of concern in industrialised countries. Contrary to organic pollutants, heavy metals are not metabolically degraded. This fact has two main consequences: its bioremediation requires another strategy and heavy metals can be indefinitely recycled. Yeast cells of Saccharomyces cerevisiae are produced at high amounts as a by-product of brewing industry constituting a cheap raw material. In the present work, the possibility of valorising this type of biomass in the bioremediation of real industrial effluents containing heavy metals is reviewed. Given the autoaggregation capacity (flocculation) of brewing yeast cells, a fast and off-cost yeast separation is achieved after the treatment of metal-laden effluent, which reduces the costs associated with the process. This is a critical issue when we are looking for an effective, eco-friendly, and low-cost technology. The possibility of the bioremediation of industrial effluents linked with the selective recovery of metals, in a strategy of simultaneous minimisation of environmental hazard of industrial wastes with financial benefits from reselling or recycling the metals, is discussed.

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In this study, efforts were made in order to put forward an integrated recycling approach for the thermoset based glass fibre reinforced polymer (GPRP) rejects derived from the pultrusion manufacturing industry. Both the recycling process and the development of a new cost-effective end-use application for the recyclates were considered. For this purpose, i) among the several available recycling techniques for thermoset based composite materials, the most suitable one for the envisaged application was selected (mechanical recycling); and ii) an experimental work was carried out in order to assess the added-value of the obtained recyclates as aggregates and reinforcement replacements into concrete-polymer composite materials. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified concrete-polymer composites with regard to unmodified materials. In the mix design process of the new GFRP waste based composite material, the recyclate content and size grade, and the effect of the incorporation of an adhesion promoter were considered as material factors and systematically tested between reasonable ranges. The optimization process of the modified formulations was supported by the Fuzzy Boolean Nets methodology, which allowed finding the best balance between material parameters that maximizes both flexural and compressive strengths of final composite. Comparing to related end-use applications of GFRP wastes in cementitious based concrete materials, the proposed solution overcome some of the problems found, namely the possible incompatibilities arisen from alkalis-silica reaction and the decrease in the mechanical properties due to high water-cement ratio required to achieve the desirable workability. Obtained results were very promising towards a global cost-effective waste management solution for GFRP industrial wastes and end-of-life products that will lead to a more sustainable composite materials industry.

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Glass fibre-reinforced plastics (GFRP) have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remoulded, and complex composition of the composite itself. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, efforts were made in order to recycle grinded GFRP waste, proceeding from pultrusion production scrap, into new and sustainable composite materials. For this purpose, GFRP waste recyclates, were incorporated into polyester based mortars as fine aggregate and filler replacements at different load contents and particle size distributions. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified polymer mortars. Results revealed that GFRP waste filled polymer mortars present improved flexural and compressive behavior over unmodified polyester based mortars, thus indicating the feasibility of the GFRP industrial waste reuse into concrete-polymer composite materials.

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Glass fibre-reinforced plastics (GFRP) have been considered inherently difficult to recycle due to both: crosslinked nature of thermoset resins, which cannot be remoulded, and complex composition of the composite itself. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent desire to save resources, recycling would convert an expensive waste disposal into a profitable reusable material. In this study, efforts were made in order to recycle grinded GFRP waste, proceeding from pultrusion production scrap, into new and sustainable composite materials. For this purpose, GFRP waste recyclates, were incorporated into polyester based mortars as fine aggregate and filler replacements at different load contents and particle size distributions. Potential recycling solution was assessed by mechanical behaviour of resultant GFRP waste modified polymer mortars. Results revealed that GFRP waste filled polymer mortars present improved flexural and compressive behaviour over unmodified polyester based mortars, thus indicating the feasibility of the GFRP industrial waste reuse into concrete-polymer composite materials.

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Ship recycling has been considered as the best means to dispose off an obsolete ship. The current state of art of technology combined with the demands of sustainable developments from the global maritime industrial sector has modified the status of erstwhile ‘ship breaking’ involving ship scrap business to a modern industry undertaking dismantling of ships and recycling/reusing the dismantled products in a supply chain of pre owned product market by following the principles of recycling. Industries will have to formulate a set of best practices and blend them with the engineering activities for producing better quality products, improving the productivity and for achieving improved performances related to sustainable development. Improved performance by industries in a sustainable development perspective is accomplished only by implementing the 4E principles, ie.,. ecofriendliness, engineering efficiency, energy conservation and ergonomics in their core operations. The present study has done a comprehensive investigation into various ship recycling operations for formulating a set of best practices.Being the ultimate life cycle stage of a ship, ship recycling activities incorporate certain commercial procedures well in advance to facilitate the objectives of dismantling and recycling/reusing of various parts of the vessel. Thorough knowledge regarding these background procedures in ship recycling is essential for examining and understanding the industrial business operations associated with it. As a first step, the practices followed in merchant shipping operations regarding the decision on decommissioning have been and made available in the thesis. Brief description about the positioning methods and important preparations for the most feasible ship recycling method ie.,. beach method have been provided as a part of the outline of the background information. Available sources of guidelines, codes and rules & regulations for ship recycling have been compiled and included in the discussion.Very brief summary of practices in major ship recycling destinations has been prepared and listed for providing an overview of the global ship recycling activities. The present status of ship recycling by treating it as a full fledged engineering industry has been brought out to establish the need for looking into the development of the best practices. Major engineering attributes of ship as a unique engineering product and the significant influencing factors on her life cycle stage operations have been studied and added to the information base on ship recycling. Role of ship recycling industry as an important player in global sustainable development efforts has been reviewed by analysing the benefits of ship recycling. A brief synopsis on the state of art of ship recycling in major international ship recycling centres has also been incorporated in the backdrop knowledgebase generation on ship recycling processes.Publications available in this field have been reviewed and classified into five subject categories viz., Infrastructure for recycling yards and methods of dismantling, Rules regarding ship recycling activities, Environmental and safety aspects of ship recycling, Role of naval architects and ship classification societies, Application of information technology and Demand forecasting. The inference from the literature survey have been summarised and recorded. Noticeable observations in the inference include need of creation of a comprehensive knowledgebase on ship recycling and its effective implementation in the industry and the insignificant involvement of naval architects and shipbuilding engineers in ship recycling industry. These two important inferences and the message conveyed by them have been addressed with due importance in the subsequent part of the present study.As a part of the study the importance of demand forecasting in ship recycling has been introduced and presented. A sample input for ship recycling data for implementation of computer based methods of demand forecasting has been presented in this section of the thesis.The interdisciplinary nature of engineering processes involved in ship recycling has been identified as one of the important features of this industry. The present study has identified more than a dozen major stake holders in ship recycling having their own interests and roles. It has also been observed that most of the ship recycling activities is carried out in South East Asian countries where the beach based ship recycling is done in yards without proper infrastructure support. A model of beach based ship recycling has been developed and the roles, responsibilities and the mutual interactions of the elements of the system have been documented as a part of the study Subsequently the need of a generation of a wide knowledgebase on ship recycling activities as pointed out by the literature survey has been addressed. The information base and source of expertise required to build a broad knowledgebase on ship recycling operations have been identified and tabulated. Eleven important ship recycling processes have been identified and a brief sketch of steps involved in these processes have been examined and addressed in detail. Based on these findings, a detailed sequential disassembly process plan of ship recycling has been prepared and charted. After having established the need of best practices in ship recycling initially, the present study here identifies development of a user friendly expert system for ship recycling process as one of the constituents of the proposed best practises. A user friendly expert system has been developed for beach based ship recycling processes and is named as Ship Recycling Recommender (SRR). Two important functions of SRR, first one for the ‘Administrators’, the stake holders at the helm of the ship recycling affairs and second one for the ‘Users’, the stake holders who execute the actual dismantling have been presented by highlighting the steps involved in the execution of the software. The important output generated, ie.,. recommended practices for ship dismantling processes and safe handling information on materials present onboard have been presented with the help of ship recycling reports generated by the expert system. A brief account of necessity of having a ship recycling work content estimation as part of the best practices has been presented in the study. This is supported by a detailed work estimation schedule for the same as one of the appendices.As mentioned earlier, a definite lack of involvement of naval architect has been observed in development of methodologies for improving the status of ship recycling industry. Present study has put forward a holistic approach to review the status of ship recycling not simply as end of life activity of all ‘time expired’ vessels, but as a focal point of integrating all life cycle activities. A new engineering design philosophy targeting sustainable development of marine industrial domain, named design for ship recycling has been identified, formulated and presented. A new model of ship life cycle has been proposed by adding few stages to the traditional life cycle after analysing their critical role in accomplishing clean and safe end of life and partial dismantling of ships. Two applications of design for ship recycling viz, recyclability of ships and her products and allotment of Green Safety Index for ships have been presented as a part of implementation of the philosophy in actual practice.

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Urban authorities in Europe are confronted with increasing demands by urban dwellers for allotment gardens, but vacant urban soil tends to be scarce and/or polluted by past industrial activities. A possible solution for local authorities could therefore be to promote rooftop gardening. However little technical information exists on certain forms of rooftop urban agriculture, called Z-Farming. In 2012, a pilot experiment was run in Paris (France). Simple and cheap systems of rooftop gardening were tested on a rooftop using as crop substrates only local urban organic waste so as to contribute to the urban metabolism. Production levels and heavy metal contents in cropping substrates and edible vegetables were measured. Available results show (i) high levels of crop production with limited inputs compared to land professional gardening, (ii) low levels of heavy metal pollutants in the edible parts of the crops, especially for Cd and Pb with respect to EU norms for vegetables and (iii) positive influence on yields on organizing the substrate in layers and enhancing the biological activity through earthworm inoculation. These encouraging results allow us to consider that rooftop gardening is feasible and seem to have a great potential to improve urban resiliency. It will nevertheless be necessary to identify more precisely the types of roof that can be used and to assess more fully the generic result of the low level of pollution, as well as the global sustainability of these cropping systems.

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El reciclaje se ha caracterizado por ser un tema importante en la última década, por el desarrollo económico, social y tecnológico que tiene consigo. Evidentemente, el sector de reciclaje se ha convertido en un sector con visión para poder conseguir un nuevo sector. Por este motivo lo que se ha querido con este trabajo de investigación es buscar nuevas manera de ver los recursos que se encuentran en cualquier lugar de las ciudades. La tesis cuenta con un sin número de argumentos que ayudarán a que las personas que lean el documento se interesen cada vez más en reutilizar los materiales que día a día encuentran. De esta manera, se puede ver una cadena de suministro, que llevará a que la materia prima que se haya mejorado sirva para realizar otro tipo de productos y genere un sostenimiento significativo a miles de personas que pueden sacarle provecho a estos materiales. Nuestros hábitos más cotidianos tienen mucho que ver con la degradación global del planeta. Actos tan rutinarios como tirar la basura sin separarla, comprar utensilios de usar y tirar o adquirir los alimentos envasados en materiales anti ecológicos o no reciclables contribuyen en gran medida a la contaminación medioambiental (Inzillo, 2000).

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This article analyses the spatial organization of Montebelluna's industrial district (Italy) as an exemple of the dinamics of urbanization phenomenon in small urban areas. The study is divided in two parts: in the first one I present the social organisation's model of production named «industrial district» and its relation with the space, which is characterizeded by the rising of diffused urbanization settlements; in the second part I try to verify some explanatory factors pointed out by different autors in this specific area with an historical analysis of processes point of view. The diffused organisation of economic and housing activity show a change in the urban morphology

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In Chapter 1, rhodium nanoparticles were supported on multiwalled carbon nanotubes (MWCNTs) and bound to the magnetic core-shell system Fe3O4@TiO2. The composite Fe3O4@TiO2-Rh-MWCNT and the intermediates were characterized by SEM, EDS and TEM. Their catalytic activity was studied using i) the hydrogenation transfer of nitroarenes and cyclohexene in the presence of hydrazine hydrate; ii) the reduction of 2-nitrophenol with NaBH4; and iii) the decoloration of pigments in the presence of hydrogen peroxide. The results were monitored by gas chromatography (i) and UV Visible (ii and iii). In the second chapter, the catalytic activity of six oxidovanadium(V) aroylhydrazone complexes, viz. [VOL1(OEt)][VOL1(OEt)(EtOH)] (1), [VOL2(OEt)] (2), [Et3NH][VO2L1] (3), [VO2(H2L2)]2·EtOH (4), [VOL1(µ -O)VOL1] (5) and [VOL2(µ -O)VOL2] (6) (H2L1 = 3,5-di-tert-butyl-2-hydroxybenzylidene)-2hydroxybenzohydrazide and H2L2 = 3,5-di-tert-butyl-2-hydroxybenzylidene)-2 aminobenzohydrazide), anchored on nanodiamonds with different treatments, was studied towards the microwave-assisted partial oxidation of 1-phenylethanol to acetophenone in the presence of tert-butyl hydroperoxide (TBHP) as oxidant. A high selectivity for acetophenone was achieved for the optimized conditions. The possibility of recycling and reuse the heterogeneous catalysts was also investigated. In chapter 3, the catalytic activity of gold nanoparticles supported at different metal oxides, such as Fe2O3, Al2O3 ZnO or TiO2, was studied for the above reaction. The effect of the support, quantity of the catalyst and temperature was investigated. The recyclability of the gold catalysts was also studied. In the last chapter, a new copper nanocomposite with functionalized mutiwalled carbon nanotubes (Cu-MWCNT) was synthesized using a microwave assisted polyol method. The characterization was performed using XRD and SEM. The catalytic activity of Cu-MWCNT was studied through the degradation of pigments, such as amaranth, brilliant blue, indigo, tartrazine and methylene blue.

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This work presents the incorporation of an industrial polymeric waste into a petroleum asphalt cement with penetration grade 50-60 (CAP 50-60). The main goal of this research is the development of a polymer-modified asphalt, with improvements in its physical properties, in order to obtain a more resistant material to the traffic loads. Furthermore, the use of this polymeric waste will result in economic and environmental benefits. The CAP 50-60 used in this research was kindly supplied by LUBNOR Lubrificantes e Derivados de Petróleo do Nordeste (produced in Fazenda Belém Aracati - Ceará) and the industrial polymeric waste was provided by a button manufacturer industry, located in Rio Grande do Norte state. This polymeric waste represents an environmental problem due to its difficulty in recycling and disposal, being necessary the payment by the industry to a landfill. The difficulty in its reuse is for being this material a termofixed polymer, as a result, the button chips resulting from the molding process cannot be employed for the same purpose. The first step in this research was the characterization of the polymeric waste, using Differential Scanning Calorimetry (DSC) Infrared spectroscopy (IR spectroscopy), and Thermogravimetric analysis (TGA). Based on the results, the material was classified as unsaturated polyester. After, laboratory experiments were accomplished seeking to incorporate the polymeric waste into the asphalt binder according to a 23 experimental factorial design, using as main factors: the polymer content (2%, 7% and 14%), the temperature of the mixture (140 and 180 oC) and the reaction time (20 and 60 minutes). The characterization of the polymer-modified asphalt was accomplished by traditional tests, such as: penetration, ring and ball softening point, viscosity, ductility and flash point temperature. The obtained results demonstrated that the addition of the polymeric waste into the asphalt binder modified some of its physical properties. However, this addition can be considered as a feasible alternative for the use of the polymeric waste, which is a serious environmental and technological problem.

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Three ranges of increasing temperatures (35-43, 37-45, 39-47degreesC) were sequentially applied to a five-stage system continuously operated with cell recycling so that differences of 2degreesC (between one reactor to the next) and 8degreesC (between the first reactor at the highest temperature and the fifth at the lowest temperature) were kept among the reactors for each temperature range. The entire system was fed through the first reactor. The lowest values of biomass and viability were obtained for reactor R-3 located in the middle of the system. The highest yield of biomass was obtained in the effluent when the system was operated at 35-43degreesC. This nonconventional system was set up to simulate the local fluctuations in temperature and nutrient concentrations that occur in different regions of the medium in an industrial bioreactor for fuel ethanol production mainly in tropical climates. Minimized cell death and continuous sugar utilization were observed at temperatures normally considered too high for Saccharomyces cerevisiae fermentations.

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The use of post-consumer materials is directly related to reducing the cost of production and extraction of natural resources. Non-recyclable materials are randomly disposed in the environment. Brazil is one of the largest consumers of PET (polyethylene terephthalate) bottles. The purpose of this paper is to describe the opportunities and challenges of the logistics model for post-consumer PET bottle recycling in Brazil, while providing knowledge of its practices along the recycling chain. The results describe the need to educate those directly and indirectly involved in the process: to reduce consumption in order to reduce the amount of waste generated: to structure the post-consumer reverse chain and engage industrial sectors and government, through public policies, to support cleaner technologies along the PET bottle production chain. (C) 2010 Elsevier B.V. All rights reserved.

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The foundry sand agglomerated with alkaline phenolic resin, used for the manufacture of molds, was found to be a residue which is able to be recycled, minimizing the costs of disposal and the environmental impact. This paper analyzes the thermomechanical regeneration and leaching processes and also assesses the influence of additives on the improvement of the mechanical properties of the sands. Besides, the industrial experiments carried out at CSN aiming at the foundry sand recycling in the covering of the blast furnace troughs are presented. (C) 2003 Elsevier B.V. All rights reserved.