Univ., Diss., 2005--Kassel

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This report focuses on recycling. As an objective neutral party, MIT has compiled a knowledge base that examines the many complex issues relating to re-cycling. Although this report was prepared at the request of the Automotive board of Governors, it was not prepared solely as an industry response document. Rather, it attempts to focus on the concerted actions that both industry and government should take. MIT hopes that the document can serve as the basis for forging international consensus on a rational approach to recycling policy. This document presents the findings and recommendations of this group to the Board of Governors. In addition to these recommendations, supporting materials in the form of four appendices, tracing specific aspects of the problem of vehicle recycling and the ways in which these problems can be analyzed, are appended. / Findings and recommendations presented to the Automobitive Board of Governors, World Economic Forum, Davos. / International Motor Vehicle Program, Materials Systems Laboratory

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This thesis reports on research undertaken to investigate the implementation of a Circular approach within the leather industry, through the definition of a framework and development of an economic decision-making support tool. The core objective of the research is to identify the underpinning opportunities and challenges involved in creating recycling solutions for leather waste. The research contributions can be considered in four key areas. The first part of the thesis consists of a review of the use of leather across industry sectors and the existing waste management and recycling systems for leather waste. On consideration of this review it clearly shows a lack of systematic thinking around the creation and optimisation of recovery systems for leather waste. This review concludes that there is significant room for improvement of the current waste management and recycling solutions for leather waste. A variety of value-added products can be recovered from these wastes but only if the leather can be successfully separated from the other materials (such as rubbers and polymers) within end-of-life products and manufacturing wastes. The second part of the research defines a framework for implementing a Circular approach within the leather industry. This framework supports mapping and characterisation of the leather waste stream and the design of recycling and processing strategies for leather waste. The third part of the research is concerned with the development of a decision-support tool for the economic viability of leather recycling systems. The support tool considers all cost factors and combines them to give a single factor upon which the economic effectiveness of different leather recycling scenarios can be evaluated. Finally, the validity of the framework for leather waste recycling is assessed through the completion of two case studies. These case studies demonstrate the flexibility of the framework in supporting both horizontal (across lifecycle) leather recycling and vertical (across industry sector) leather recycling. In summary, the research clearly highlights the need for systematic thinking and flexible strategies when creating leather recycling systems. Failure to incorporate flexibility into future recycling systems puts the recycling industries at risk of being unable to effectively manage future waste streams. Conversely, early consideration and incorporation of flexible processing strategies into recycling systems could enable the recovery of high-quality recycled materials that support a circular approach to manufacturing and resource use.

The pressure at the turn of the 21st century for Waste Disposal Authorities to change their waste disposal systems was both urgent and comprehensive, with emphasis being placed on moving towards the 3Rs; Reducing, Recycling and Recovering value from Municipal Wastes. This thesis explores how a mass balance model was created for the Brighton & Hove City and East Sussex County council Private Finance Initiative (PFI) contract, in response to the pressures for change and need for investment up to 2002. An identification and evaluation of the drivers for change at the time has been undertaken; with it being demonstrated that legislation, lack of landfill space and underlying public pressure were the stimulus for change.

Carbon dioxide emissions per year have risen exponentially. It is widely known the contribution of CO2 to global warming phenomena, so storage/utilisation of carbon dioxide has become a topical issue and an emerging research area. Despite the fact that utilization of CO2 waste would not solve the problem of the huge quantities going to the atmosphere every year as only less than 1% of it could be reused for the industry, recycled carbon dioxide presents itself as a possible cheap and accessible chemical feedstock. The challenge on recycling CO2 is to minimize energy and cost efficiency of any suitable reaction. On previous investigations the electrochemical synthesis of 5-membered cyclic carbonate from epoxides was accomplished under mild conditions and optimized (1 atm CO2 pressure, 60 mA constant current and 50 °C heating). In order to understand the mechanism of this electrochemical process a deep investigation on the variables of the synthesis of cyclic carbonates was carried out and is presented in this thesis. The variables studied include electrochemical system conditions (application of current through Cu/Mg electrodes, electrodes connected on a closed circuit system with no current, an open circuit system where electrodes were there was no connection between them, and reactions without electrodes), temperature of reaction, solvent screening, catalysts, epoxide substituents, concentration of species and ratio of reactants. As a result of the variables optimization, a new, cheap, simple and relatively fast method (5 to 24 hours of reaction time) for cyclic carboxylation of epoxides with CO2 at atmospheric pressure in acetonitrile in the presence of ammonium salt (TBAI) at mild temperatures (50-75 °C) has been developed and improved. The concentration of the reactants, especially of the epoxide, was found to be the most important factor on the success of the reaction. The new reaction conditions also allow converting epoxides to carbonates without the help of any cocatalyst or electrochemical system obtaining excellent yields (50-100%) with the important saving on cost and energy of co-catalyst synthesis and recovery. Chlorostyrene oxide (1 M) reacted almost completely (94%) after 24 hours with TBAI (1 M), in 1 mL of acetonitrile at 75 °C and 1 atm pressure of CO2. Epoxide carboxylation under neat conditions was feasible, producing 44% of chlorostyrene carbonate from chlorostyrene oxide in the presence of TBAI at 75 °C and 1 atm pressure of CO2.

Orientador: Adler Guilherme Viadana. / Banca: José Carlos Godoy Camargo / Banca: José Francisco / Resumo: Atualmente, a geração de resíduos sólidos urbanos apresenta-se como um problema de graves proporções por causa da grande quantidade gerada diariamente e da potencialidade do lixo em se transformar em foco de doenças e/ou contaminação do solo, do ar e das águas superficiais e subterrâneas. O seu gerenciamento, responsabilidade do poder público, não é das tarefas mais fáceis porque envolve determinados procedimentos técnicos e tecnológicos que, devido aos seus elevados custos, nem sempre estão ao alcance de diversos países, estados ou municípios. Nos países pobres os depósitos de lixo ainda apresentam o agravante social de serem freqüentados por milhares de pessoas, de todas as idades, em busca de restos de comida ou material reciclável. O presente trabalho procura analisar a geração do lixo, relacionando-a com as formas de consumo difundidas pelo modo de produção capitalista, e as conseqüências sociais e ambientais que advêm de tal geração. Elegeu-se o município de Ribeirão Preto (SP) para uma análise mais aprofundada porque a cidade dispõe de coleta seletiva, aterro sanitário e de uma cooperativa de reciclagem formada por pessoas que, anteriormente, sobreviviam da coleta de lixo no aterro local. / Abstract: Currently, the production of urban solid waste became a serious problem to the cities because of the great amount of garbage produced by people every day. Moreover, the garbage is still a source of illnesses transmission and/or contamination of the soil, air and also the superficial and underground waters. Its management, a government's responsibility, it's not one of the easiest tasks because it involves definitive technical and technological procedures, that, due to their high costs, it's not available in some countries, states or cities. In poor countries garbage is still a way of survival for all age thousands of people, who search for food or anything that can be recycled. The present work analyses the garbage production related to the forms of consumption spread by the capitalist production way, and the social and environmental results that come from such garbage production. Ribeirão Preto city was chosen for a deeper analysis because it has selective garbage collection, landfill, and a recycling cooperative composed by people who were once dependant on the collection at the local landfill to survive. / Mestre

Many countries in the world today have reached the point of full utilization of their forest resources, to satisfy their need for lumber and pulp and paper products. Others have reached the point where their consumption is far in excess of the capacity their domestic forest stands can sustain and they are net importers of these products. Still fewer have developed the practice of recycling these products to any appreciable extent. Canada and United States are approaching full utilization and have only accomplished a recycling rate of approximately 20% of paper and paperboard products. On the other hand conservationists are calling for more efficient utilization of resources, ecologists are calling for less waste and less pollution, while the burden on city garbage collection facilities, 50% of which is paper products, is increasing exponentially. In this thesis the technical processes required to make first quality newsprint from recycled newspaper are shown to be available. The economics of such a plant is examined in detail leading to the judgment that it is economically sound. The conclusion is reached that a 300 ton/ day newsprint mill can be entirely supported by locally generated waste newspaper in a city of three million population or over. Furthermore, it is concluded that if the collection and transportation of waste newspapers is not impeded by governmental regulations or unanticipated competition in the feeder cities, such a plant is still economically feasible after allowing for water barge transportation of the raw materials as far as 200 miles. / Business, Sauder School of / Graduate

By identifying these sampling of systems, research was undertaken to connect possible systems to create a technology platform. This system being one possibility within ideas already thought out from groups like Archigram and the Metabolism group until today with all the debate from container architecture to prefabricated houses and buildings. This is not an effort to propose new ways of thinking in architecture, but combining ideas and systems out in the open to create a system and a building, being able to fit into context in Africa and also in the systems and context of the bigger world. The Theoretical investigation (pp. 10-16) was not supplied by the student / Dissertation (MArch(Prof))--University of Pretoria, 2008. / Architecture / unrestricted