Thesis (MBA)--Stellenbosch University, 2012. / Tyre waste from end-of-life tyres (ELTs), sometimes erroneously defined as a type of waste, in fact represents a renewable energy resource that is highly competitive as replacement fuel to coal in the form of tyre-derived fuel (TDF) or useable as rubber crumb in other products. In this research study, the main utilisation options considered were based on rubber crumbing through ambient and cryogenic processing. Pyrolysis, the so-called ‘holy grail’ of tyre technologies, rubberised asphalt products, TDF options and various other product options from tyre crumb as basis were considered. Although pyrolysis technology is highly commendable and environmentally friendly, it is still a process with too many variants and presents an unstable economic model that is not attractive to entrepreneurs. Rubberised asphalt depends on policy decisions from local and national authorities supporting initial higher spending and allowances on budgets to acquire future savings from the longevity in the product. The policy requirements and the instability that politically-inspired decisions carry with them are contributing to the unattractiveness of this solution to the entrepreneurial fraternity. Through government requiring a certain percentage of asphalt pavements to contain rubber (like in the United States of America (USA)), rubberised asphalt could be a very useful and viable option to produce. In the USA, the Environmental Protection Agency (EPA) recently avoided the return to coal in industrial kilns currently using TDF based on its beneficial carbon dioxide (CO2) emission and cost structures by defining TDF as Reasonably Available Control Technology (RACT) to existing coal-burning industrial kilns. In South Africa, the usage of TDF should be of interest to Eskom and the cement industry. TDF (produced from end-of-life tyres), defined as a renewable energy resource due to its proven biomass component and with its high calorific value, presents higher energy output values in comparison to coal and furthermore presents the industry with lower input costs per ton and reduces the CO2 emission factor. Entrepreneurial intervention involving Eskom and/or the cement industry in South Africa with the utilisation of end-of-life tyres as renewable energy resource is an overdue business opportunity. With more than ten million tyres per year available in South Africa and a stockpile of more than fifty million waste tyres, sustainability of TDF supplies is a reality. TDF is much cheaper per ton than coal and emits approximately 20 percent less CO2 and/or CO2e than low-grade coal to produce the same electricity output. From all the information gathered, it is clear that in countries where coal energy is extensively used, TDF utilisation not only reduces the tyre waste issues, but it also serves as an environmentally-friendly renewable energy resource in electricity production and cement kilns; the industry with some of the highest CO2 emission risks. The final chapter of this report presents a schedule representing the choice of tyre processing and disposal methods ranked by environmental preference and defining the priorities linked to process and product choice.

[pt] Há mais de um século a humanidade usufrui de um invento essencial ao desempenho, economia e conforto à rodagem de veículos: o pneu. Entretanto, o pneu tem uma vida útil limitada, caracterizada pela redução de suas ranhuras - até o limite que comprometa a estabilidade do veículo. Uma vez ultrapassada a vida útil, sobra uma carcaça, constituída por materiais de alta resistência e toxicidade, que vem sendo, simplesmente, descartada e lançada à natureza. Em conseqüência, o pneu é considerado hoje um dos maiores problemas ambientais do mundo. Além de demorar até 600 anos para se decompor, um pneu pode causar diversos malefícios para a sociedade e o meio ambiente, quando dispostos inadequadamente. É nesse contexto que a logística reversa pós-consumo vem se desenvolvendo, ou seja, estudando maneiras de como um produto descartado pela sociedade pode retornar ao ciclo de negócios. Este trabalho apresenta um estudo do problema logístico reverso na reciclagem industrial por pirólise com xisto de pneus. O objeto de estudo será o programa Paraná Rodando Limpo, um projeto desenvolvido no estado do Paraná, que coleta e recicla pneus descartados. Além de descrever os agentes envolvidos, traçar e caracterizar a rede reversa desde a captação, transporte e reciclagem dos pneus, um estudo de otimização de rotas foi proposto para tornar o processo mais eficiente. / [en] For more than a century, the world civilization has benefited from an invention to essential the performance, cost reduction, and comfort of vehicles: the tire. However, the tire has a limited useful life, characterized by the reduction of its grooves, up to a limit that jeopardizes the stability of the vehicle. Once such useful life is exceeded, a carcass constituted by high- resistance and toxicity materials is discharged and thrown away in the environment. As a consequence, today the tire is considered one of the largest environmental problems in the world. It takes more than 600 years for a tire to decompose, resulting, when not properly disposed, in several problems to the society and its environment. In this context the post-consumption reverse logistics is being developed, namely, studying ways for a product that has been discarded by the society returning to the business cycle. This work presents a study of a reverse logistics problem in the industrial recycling of tires by pyrolysis with shale. The object of study will be the Parana Rodando Limpo project (Parana running in a clean way) developed by the State of Parana, which is in charge of collecting and recycling tires that are discharged. The study describes all the involved agents, outlines and characterizes the reverse logistics flows including the collection, the transport and the recycling of the tires and, in addition, proposes a routing optimization study in order to improve the efficiency of the process.

Orientador: Luísa Andréia Gachet Barbosa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-26T12:45:29Z (GMT). No. of bitstreams: 1 Silva_FabianaMariada_M.pdf: 2221147 bytes, checksum: acb168d3d261f81f3d6f6d1d25e50816 (MD5) Previous issue date: 2014 / Resumo: O reaproveitamento de resíduos na construção civil tem sido uma alternativa viável para diminuir o consumo de materiais naturais e a disposição inadequada dos resíduos no meio ambiente. Neste trabalho avaliou-se o reaproveitamento de resíduo de borracha de pneus, proveniente do processo de recauchutagem, em substituição parcial do agregado miúdo natural, para a produção de pisos táteis intertravados de concreto. O piso tátil de concreto é uma peça utilizada na pavimentação, que permite a percepção do ambiente ou rotas acessíveis, proporcionando mais segurança e autonomia para as pessoas com deficiência visual. A substituição foi feita em relação à massa da areia nas proporções de 10%, 20%, 30%, 40% e 50%. As seguintes propriedades do concreto foram investigadas: consistência no estado fresco, resistência à compressão, resistência à tração na flexão, absorção de água, índice de vazios, massa específica do concreto endurecido, resistência à abrasão, resistência ao impacto e análise de microestrutura. Embora a grande limitação do uso da borracha de pneus como agregado no concreto seja a redução das resistências mecânicas, os traços com até 50% de substituição atingiram ótimos valores de resistência à compressão e resistência à tração na flexão e apresentaram melhores resultados de resistência à abrasão. A utilização do resíduo de borracha de pneus, em substituição parcial da areia natural no concreto para a produção de piso tátil, além de contribuir com a sustentabilidade na construção civil, por meio da economia de extração de matérias-primas e redução do descarte e acúmulo inadequado de pneus inservíveis, proporcionou melhorias a algumas propriedades importantes para a eficiência e qualidade do piso tátil de concreto / Abstract: The reuse of waste in construction has been a viable alternative to reduce the consumption of natural materials and the improper disposal of waste on the environment. In this work recycled tire rubber (crumb rubber) was used as aggregate in concrete to produce tactile paving block. The concrete tactile paving block allows perception of the place or accessible routes, providing more security and independence for people with visual disabilities. The crumb rubber was used to replace sand by mass at the level of 10%, 20%, 30%, 40% and 50%. The concrete characterization was performed by testing its consistency, compressive strength, flexural strength, water absorption, porosity, density, abrasion resistance, impact resistance and microstructure analysis. Although the major limitation using the crumb rubber as aggregate in the concrete is to reduce the mechanical strength, the mixtures with up to 50% of substitution reached optimal values ??of compressive strength and flexural strength and showed a better abrasion resistance. The use of crumb rubber in partial replacement of natural sand in concrete to produce tactile paving block, proved to be a viable alternative. Besides contributing to construction sustainability, minimizing the extraction of raw materials, and reducing improper disposal and accumulation of scrap tires, provided improvements to some important properties that assure the efficiency and quality of the concrete tactile paving block / Mestrado / Tecnologia e Inovação / Mestra em Tecnologia

The research work critically analyzed the factors responsible for imprudent waste tyre management in South Africa. As an approach to determine the complexity of the problem, questionnaires were sent to one hundred and sixty (160) respondents in conjunction with interviews. Perusal of literature and interaction with industry involved in waste tyre processing to further gain knowledge of the problem and possible solutions that can be solicited to address the problem. Findings revealed that, lack of clear, focused legislation that guide the handling, disposal and processing of waste tyres remain the challenge. It is also deduced that recycling of waste tyres can provide economic benefits and opportunities. It is recommended that South Africa develop appropriate legislation that deals with handling, treatment and disposal of waste tyres, develop an incentive programme to set up initiatives as well as developing skilled and capacitated enforcement agency. / Environmental Sciences / M.A. (Environmental Management)

The research work critically analyzed the factors responsible for imprudent waste tyre management in South Africa. As an approach to determine the complexity of the problem, questionnaires were sent to one hundred and sixty (160) respondents in conjunction with interviews. Perusal of literature and interaction with industry involved in waste tyre processing to further gain knowledge of the problem and possible solutions that can be solicited to address the problem. Findings revealed that, lack of clear, focused legislation that guide the handling, disposal and processing of waste tyres remain the challenge. It is also deduced that recycling of waste tyres can provide economic benefits and opportunities. It is recommended that South Africa develop appropriate legislation that deals with handling, treatment and disposal of waste tyres, develop an incentive programme to set up initiatives as well as developing skilled and capacitated enforcement agency. / Environmental Sciences / M.A. (Environmental Management)