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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.
241

Social media to support collaboration in the product life cycle of SMEs / Médias sociaux pour supporter la collaboration dans le cycle de vie des produits et services des PME

Doyon-Roch, Jérémi January 2016 (has links)
Abstract : The use of social media tools to support small and medium-sized enterprises (SME) to support their business activities throughout the product life cycle (PLC) phases represents an interesting opportunity. SMEs operate in very competitive environments, and face significant challenges primarily caused by their size disadvantage. By nature, social media tools and platforms can enable them to overcome some of these challenges, as they are often very inexpensive, familiar and easy to use, allowing them to reach large audiences they would not be able to reach with traditional and expensive marketing initiatives. To provide solutions to this problem, this research identified three main objectives. The first objective was to draw a picture of the existing academic literature on the use of social media tools in the PLC context to better understand how these tools were studied and used in businesses, and for what purpose. Second, this research aimed at understanding how SMEs actually use social media tools to support their different business activities to identify the gap between academic research and actual business practices. Finally, based on the findings highlighted from the previous objectives, this research aimed at developing theory on this topic by proposing a conceptual framework of customer engagement enabled by social media. The conceptual framework aimed at answering general questions that emerged from the initial two objectives: Why do some SMEs use social media to support customer engagement, while others do not? Why do firms use different social media tools to support their customer engagement initiatives? Why does the scope of customer engagement initiatives (i.e., across different PLC phases) vary between SMEs? What are the potential outcomes of conducting customer engagement initiatives for the organizing firms? In order to achieve these research objectives, the methodology employed for this research is threefold. First, a systematic literature review was performed in order to properly understand how the use of social media tools in the PLC context had been studied. The final results consisted of 78 academic articles which were analyzed based on their bibliometric information and their content. Second, in order to draw the contrast between the academic publications and managerial reality of SMEs, six semi-structured interviews were conducted to understand how these firms actually use social media to support different activities in each of the PLC phases. Third, five additional semi-structured interviews were performed to gather a deeper understanding of this phenomenon and generate theory to support the proposed conceptual framework. The conceptual framework focuses on the degree of customer engagement, which is comprised of the scope (PLC phases) of customer engagement and the technology (social media tools) employed to support these initiatives. Two sets of antecedents were examined, firm motivators and firm impediments, as they could both potentially affect the scope and the social media tools used to support customer engagement initiatives. Finally, potential customer engagement outcomes for SMEs developing these initiatives were also examined. The semi-structured interviews lasted approximately 25-35 minutes, and were performed using an interview grid consisting of 24 open-ended questions. The interview grid was developed based on the findings of the systematic literature review, and this qualitative approach allowed for a rich understanding of the interviewed SMEs’ use of social media tools to support and engage customers in their different PLC activities. The main results highlighted by this project demonstrate that this field is relatively recent and sees constant increase in research interest since 2008. However, most of the academic research focuses on the use of social media tools to support innovation activities during the new product development process, while the interviewed firms almost exclusively used the tools to engage customers in the later phases of the PLC, primarily for promotion, customer service support, and business development activities. Interestingly, the interviewed firms highlighted several benefits of using social media tools to engage customers, some of which could help them overcome certain size disadvantages previously mentioned. These firms are in need of further guidelines to properly implement such initiatives and reap the expected benefits. Results suggest that SMEs are far behind both large companies and academic research in their use of social media to engage customers in different business activities. The proposed conceptual framework serves as a great tool to better understand their reality and eventually better support them in their social media and customer engagement efforts. However, this framework needs to be further developed and improved. This research project provides a 360-degree view of the phenomenon of the use of social media to support customer engagement for SMEs, by providing both a thorough systematic review of the academic research and an understanding of the managerial reality of SMEs behind this phenomenon. From this analysis, a conceptual framework is then proposed and serves as a stepping stone for future researchers who are interested in developing theory in this field. / Résumé : L’utilisation des médias sociaux en support aux activités d’affaires dans chaque phase du cycle de vie des produits et services des petites et moyennes entreprises (PME) représente une excellente opportunité pour les entreprises cherchant à se différencier du marché et se rapprocher de leur clientèle. Les PME œuvrent dans des milieux extrêmement compétitifs et doivent faire face à cette concurrence avec des ressources généralement inférieures aux grandes entreprises qui œuvrent dans la même industrie. L’idée d’identifier comment les technologies peuvent soutenir les PME et réduire l’écart qui les sépare de certains joueurs dans leurs milieux respectifs est apparue comme un sujet pertinent, ayant le potentiel d’amener une contribution académique et managériale. Les médias sociaux ont, par leur nature, le potentiel de permettre aux PME de rejoindre les masses, démontrer de la créativité et ainsi être plus compétitifs que jamais. Les médias sociaux s’avèrent d’autant plus pertinents puisqu’ils sont accessibles à relativement moindre coût, nous sommes familiers avec ces outils et ils sont généralement faciles à utiliser. Ils peuvent ainsi permettre aux entreprises d’accomplir des choses que leurs ressources ne pourraient normalement pas leur permettre. Afin de soutenir les PME dans leurs efforts pour réduire cet écart face aux grandes entreprises, ce projet de recherche identifie trois principaux objectifs. Le premier objectif était de dresser un portrait de la littérature scientifique sur l’utilisation des outils de médias sociaux dans le contexte de cycle de vie des produits afin de mieux comprendre comment ces outils ont été étudiés et utilisés en entreprises. En second lieu, cette étude avait comme but de comprendre comment les PME utilisent les médias sociaux pour supporter leurs différentes activités d’entreprises afin d’identifier l’écart entre la littérature scientifique et la réalité de monde des affaires. Finalement, cette recherche vise à développer de la théorie sur ce sujet en proposant un cadre conceptuel sur l’engagement des consommateurs soutenu par les médias sociaux. Le cadre conceptuel a comme objectif de répondre aux questions qui ont émergé en analysant les réponses aux deux premiers objectifs: pourquoi certaines PME utilisent les médias sociaux pour soutenir l’engagement des consommateurs alors que d’autres ne le font pas? Pourquoi les entreprises utilisent-elles différents outils de médias sociaux pour soutenir leurs initiatives d’engagement des consommateurs? Pourquoi est-ce que la portée (différentes phases du cycle de vie des produits) des initiatives d’engagement des consommateurs varie entre les PME? Quels sont les aboutissements potentiels pour une organisation qui met sur pied une initiative d’engagement des consommateurs? Dans le but de répondre à ces objectifs, la méthodologie employée est constituée de trois étapes distinctes. Premièrement, une revue systématique de la littérature a été exécutée afin de comprendre comment l’utilisation des médias sociaux dans le contexte de cycle de vie des produits a été étudiée. 78 articles ont répondu aux critères d’exclusion et ont été analysés afin de faire ressortir des résultats basés sur leur information bibliométrique et leur contenu. Deuxièmement, afin de délimiter l’écart entre les publications académiques et la réalité des PME, six entrevues semi-structurées ont été menées afin de comprendre comment ces entreprises utilisent les médias sociaux pour supporter différentes activités dans chaque phase du cycle de vie des produits. Troisièmement, cinq entrevues semi-structurées supplémentaires ont été menées afin d’obtenir une compréhension plus en profondeur de ce phénomène et ainsi générer de la théorie pour développer davantage le cadre conceptuel proposé. L'accent du cadre conceptuel est le degré d’engagement des consommateurs, qui comprend la portée (phases du cycle de vie des produits) de l’engagement des consommateurs et les technologies (outils de médias sociaux) utilisées pour soutenir ces initiatives. Deux antécédents ont été examinés, soient les motivateurs et les obstacles aux entreprises, puisqu’ils pourraient tous deux potentiellement affecter la portée et les outils de médias sociaux utilisés en soutient aux initiatives d’engagement des consommateurs. Finalement, les aboutissements potentiels à engager les consommateurs pour les PME qui mettent sur pied ce genre d’initiatives sont également examinés. Les entrevues semi-structurées étaient d’une durée d’environ 25 à 35 minutes. Une grille d’entrevue composée de 24 questions ouvertes a été utilisée afin d’orienter les entrevues et collecter des données. Cette grille a été développée en fonction de l’analyse et des résultats provenant de la revue systématique de la littérature. L’approche qualitative de ces entrevues a permis d’obtenir une compréhension en profondeur de l’utilisation des médias sociaux en support à l’engagement des consommateurs dans diverses activités du cycle de vie des produits des PME. Les principaux résultats de ce projet illustrent que ce domaine d’étude est relativement récent et illustrent une constante croissance dans l’intérêt de recherche pour ce sujet de recherche depuis 2008. Cependant, la plupart des recherches académiques mettent l'accent sur l’utilisation des médias sociaux en support aux activités d’innovation lors des phases du processus de développement de nouveaux produits, alors que les entreprises interviewées utilisent presque exclusivement les médias sociaux pour engager les consommateurs à des fins de promotion, service à la clientèle et développement d’affaires lors des dernières phases du cycle de vie des produits. Il est intéressant de noter que les entreprises interviewées ont identifié plusieurs bénéfices à utiliser les médias sociaux afin de surmonter certains désavantages mentionnés ci-dessus. Ces bénéfices potentiels illustrent l’importance pour ces PME de bénéficier de plus amples directives et recommandations afin d’effectivement implanter ces initiatives et de récolter ces bénéfices potentiels. Nos résultats nous ont permis de comprendre que les PME sont en retard sur les grandes entreprises et le milieu académique dans leur utilisation des médias sociaux pour engager les consommateurs dans diverses activités d’entreprises. Le cadre conceptuel proposé est un excellent outil permettant de mieux comprendre la réalité des PME et éventuellement de mieux les supporter dans leur implantation de divers médias sociaux et leurs efforts pour engager des consommateurs. Cependant, ce cadre conceptuel nécessite davantage de recherches afin de le développer davantage et l’améliorer. Cette recherche se différencie des autres recherches dans ce domaine en fournissant une vue globale de ce phénomène, soit une rigoureuse revue systématique de la littérature académique, ainsi qu’une analyse de la réalité pratique des PME. De cette analyse, un cadre conceptuel est proposé et sert de fondement pour les futurs chercheurs qui souhaitent développer de la théorie reliée à ce domaine d’étude.
242

Application of life cycle analysis (LCA) to consumer product development

Chan, Wah-man, 陳華民 January 2002 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
243

Life cycle assessment in the construction industry

Yiu, W. Y., 姚泳儀. January 2001 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
244

Entrepreneurial Development : The Impact of Mentorship in the Entrepreneurial Process

Wallstedt, Erik, Wennerström, Linus January 2009 (has links)
<p>A sustainable development of entrepreneurship will not be possible in such a complex andchallenging environment as today’s society, without the attainment of effective learning andbusiness support capabilities (Williams, 1998). One such support is obtained through havingexperienced entrepreneurs mentor less experienced entrepreneurs, transferring knowledge(Clutterbuck, 2004) and facilitating learning (Sullivan, 2000). As Leonard Bisk (2002)and Sullivan (2000) among other researchers (Deakins et al. 1997) stress, there is a need tolook beyond the start-up process of a firm and the use of mentorship in this early phase,and focus more on how entrepreneurs who have been in business for a while can benefitfrom a mentor program, an area referred to as “the nature of timing and support” (Sullivan,2000, p. 163).</p><p>The purpose of this thesis is to explore how an experienced entrepreneur, a mentor, canhelp a less experienced entrepreneur, an adept, achieve entrepreneurial development duringand throughout different phases of the entrepreneurial life cycle, in the most efficient manner.</p><p>An entrepreneurial life cycle can be divided into several phases, which can be used in orderto examine the entrepreneur’s development process within different time periods of runninga firm. Start-up support generally involves providing entrepreneurs with the crucial“tools” for survival, such as basic financial support, bookkeeping and marketing (Sullivan,2000). Mature entrepreneurs generally request psychological benefits, such as reassuranceand improved confidence as they wonder whether or not their experiences are normal andhow they should be interpreted (Megginson et al. 2006). There are two types of directivementoring styles, coaching and counseling, and two types of non directive mentoring,counseling and networking.</p><p>The main objective with our research in this thesis was to explore how entrepreneurs’ developmentthroughout and during different phases was affected by active participation in amentor program. To gather information we used a qualitative method, in which we interviewedten entrepreneurs who were currently active in a mentor program, or had been activewithin the last 12 months. The empirical findings were later analyzed in the light of theframe of references and the authors own viewpoint, by conducting a within case/cross casecomparisons.</p><p>The results indicate that a mentor can best help an entrepreneur achieve entrepreneurialdevelopment by providing non directive support, enabling the entrepreneur to draw his orher own conclusions and stimulate self reliance. This support is best delivered after thestart-up and conception phase, the first phase of the life-cycle.</p>
245

Life-Cycle Costing : Applications and Implementations in Bridge Investment and Management / Sustainable and cost-efficient procurement and management of bridge infrastructure

Safi, Mohammed January 2013 (has links)
A well-maintained bridge infrastructure is a fundamental necessity for a modern society that provides great value, but ensuring that it meets all the requirements sustainably and cost-effectively is challenging. Bridge investment and management decisions generally involve selection from multiple alternatives. All of the options may meet the functional demands, but their life-cycle cost (LCC), service life-span, user-cost, aesthetic merit and environmental impact may differ substantially. Thus, life-cycle analysis (LCCA, a widely used decision-support technique that enables comparison of the LCC of possible options), is essential. However, although LCCA has recognized potential for rationalizing bridge procurement and management decisions its use in this context is far from systematic and the integration of LCCA findings in decisions is often far from robust. Thus, the overall objective of the work underlying this thesis has been to contribute to the development of sustainable bridge infrastructures while optimizing use of taxpayers’ money, by robustly incorporating life-cycle considerations into bridge investment and management decision-making processes. The work has introduced a full scheme for applying LCCA throughout bridges’ entire life-cycle. Several practical case studies have been presented to illustrate how an agency could benefit from use of a bridge management system (BMS) to support decisions related to the management of existing bridges and procure new bridges. Further developments include a comprehensive approach incorporating a novel LCCA technique, “LCC Added-Value Analysis”, which enables procurement of the most cost-efficient bridge design through a fair design-build (D-B) tendering process. A further contribution is a novel, holistic approach designed to enable procurement of bridges with the maximal possible sustainability (life-cycle advantages) under D-B contracts. The approach combines LCC Added-Value analysis with other techniques that make bridges’ aesthetic merit and environmental impact commensurable using an adapted concept named the willingness-to-pay-extra (WTPE). The systematic analytical procedures and potential of LCCA to deliver major savings highlighted in this thesis clearly demonstrate both the feasibility and need to integrate LCCA into bridge procurement and management decisions. This need has been recognized by Trafikverket (the Swedish Transport Administration), which has implemented a software tool developed in the research (BaTMan-LCC) in its bridge and tunnel management system (BaTMan). This thesis introduces readers to the field, considers BaTMan and the bridge stock in Sweden, discusses the developments outlined above and obstacles hindering further implementation of LCCA, then presents proposals for further advances. / <p>QC 20131029</p>
246

Energy Considerations for Pipe Replacement in Water Distribution Systems

Prosser, MONICA 21 August 2013 (has links)
Water utilities are facing pressure to continue to provide high-quality potable water in an increasingly energy constrained world; managing the ageing infrastructure that exists in many countries is a challenge in and of itself, but recently this has been coupled with political and public attention to the environmental impacts of the distribution system. Utility managers need to take a holistic approach to decision-making in order to determine all of the impacts of their plans. The intention of this thesis is to present a set of considerations for utility planners and managers to provide clarity to the trade-offs associated with any pipe replacement decision. This research has examined the energy relationships between operational energy reduction and the embodied energy tied to replacing deteriorated pipes in water distribution networks. These relationships were investigated through the development and application of a life-cycle energy analysis (LCEA) for three different pipe replacement schedules developed with the intent to reduce leakage in the system. The results showed that the embodied energy for pipe replacement is significant even when compared against the large amount of energy required to operate a large-scale water utility. The annual operational energy savings of between 8.9 and 9.6 million kWh achieved by 2070 through pipe replacement comes at a cost; 0.88-2.05 million kWh/mile for replacement with ductile iron pipes with diameters of 6” to 16” respectively. This imbalance resulted in a maximum energy payback period of 17.6 years for the most aggressive replacement plan in the first decade. Some of the assumptions that were used to complete the LCEA were investigated through a sensitivity analysis; specific factors that were numerically queried in this chapter include the break rate forecasting method, pumping efficiency, the leakage duration and the flow rate per leakage event. Accurate accounting of energy requirements for pipe replacement will become even more important as energy and financial constraints continue to increase for most water utilities, this thesis provides guidance on some of the complex relationships that need to be considered. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-08-21 16:51:18.963
247

Novel retrofit technologies incorporating silica aerogel for lower energy buildings

Dowson, Mark January 2012 (has links)
The aim of this Engineering Doctorate is to design, build and test novel environmental retrofit technologies to reduce energy consumption in existing buildings. Three contributions to knowledge are documented. The first contribution is the technical verification of a novel proof-of-principle prototype incorporating translucent silica aerogel granules to improve the thermal performance of existing windows without blocking out all of the useful natural light. The study demonstrates that a 10 mm thick prototype panel can reduce heat loss by 80 %, without detrimental reductions in light transmission. Payback periods of 3.5-9.5 years are predicted if applied as openable shutters or removable secondary glazing. The second contribution is a streamlined life cycle assessment of silica aerogel following the ISO 14000 standards. The study assesses the raw materials and electricity use associated with two of the three known methods of aerogel production. Despite being produced in a laboratory that had not been refined for mass manufacture, the production energy and CO2 burden from aerogel production can be recovered within 0-2 years when applied in a glazing application. The third contribution is the development and verification of a novel solar air heater incorporating granular aerogel, retrofitted to an external south facing wall, preheating the air in a mechanical ventilation system with heat recovery on a hard4to4 treat domestic property. During the 7-day in-situ test, peak outlet temperatures up to 45 °C were observed and validated to within 5 % of predictions, preheating the dwelling’s fresh air supply up to 30 °C, facilitating internal temperatures of 21-22 °C without auxiliary heating. The predicted financial and CO2 payback for a range of cover thicknesses is 7-13 years and 0-1 years, respectively. Efficiency up to 60 % and a financial payback of 4.5 years is predicted with an optimised design incorporating a 10 mm thick granular aerogel cover.
248

Livscykelkostnad för olika grader av automatiserat underhåll : LCC för manuell och semiautomatisk kameratvätt i Sveriges vägtunnlar / Life cycle cost of maintenance with different levels of automation

Ljungberg, Emil January 2016 (has links)
At the Swedish Transport Administration two different maintenance strategies are practiced to keep cameras in road tunnels clean. The theory of Life Cycle Cost, LCC, is applied on maintenance depending on its Level of Automation, LoA, and is further developed. In the case of cameras, in Swedish road tunnels the processes demonstrate two different LoA. LCC is used to compare and analyze how the properties between semiautomatic and manual maintenance affect investment costs, operational costs and the cost of preventive and corrective maintenance. Semiautomatic cleaning maintenance of cameras in road tunnels indicate a larger LCC than manual maintenance. This is due to a larger investment cost for machinery, but a similar annual cost for preventive maintenance. The presented properties affecting LCC are placed in a general context. This emphasize the significance of examining costs at high level of detail and comprehend the properties causing the costs.
249

Environmental impacts of food waste in a life cycle perspective : A case study in a Swedish supermarket

Brancoli, Pedro January 2016 (has links)
The food production system has been acknowledged as a problem that needs to be addressed in order to achieve a sustainable society. Hertwich and Peters (2009), estimate that 10-30% of an individual’s environmental impact is related to the industrial production and consumption of food. The problem is aggravated by the wastage of one third of the global food production. The consequences of the wastage of food are the loss of resources, such as energy, water, land and labour and unnecessary emissions of pollutants. In order to address this problem several actions have been proposed. The Sustainable Development Goal 12.3, which Sweden has committed to fulfil, aims to reduce by half the amount of food waste along the production and supply chain by 2030. Retail is an important player in the food supply chain. Its influence spreads both upstream to suppliers and downstream to consumers. Therefore, this research aims to contribute to reduction of the environmental impacts related to food waste in retail, by identifying products with high environmental impacts. The main goals of this study are 1) the quantification of food waste produced by the supermarket and 2) to examine the environmental impacts of selected products in order to assess the impacts generated by the waste production at the supermarket. The findings of the research revealed 1) the importance of not only measuring the food waste in terms of mass, but also in terms of environmental indicators and costs. The results indicate bread as an important contributor for the environmental footprint of the supermarket and a potential product for interventions 2) Sorting the organic content of the products from its packaging before sending it to the current waste treatment leads to a reduction in the carbon footprint. The research identified the following recommendations: 1) increasing supermarket personnel and consumers’ awareness regarding the environmental impact of food waste, 2) finding alternative routes for waste treatment and 3) improving logistic operations.
250

Avaliação do desempenho ambiental de alternativas de reaproveitamento de vinhaça decorrente da produção de etanol. / Environmental performance evaluation of vinasse reuse alternatives resulting from ethanol production.

Sánchez Moore, Claudia Cristina 01 April 2016 (has links)
A obtenção de etanol a partir de rotas alcoolquímicas consagradas gera resíduos com potencial de aproveitamento, tanto em outros setores produtivos como no ciclo produtivo do próprio combustível. Este é o caso de torta de filtro e vinhaça. A vinhaça em particular costuma ser devolvida ao campo com o intuito de ajustar teores nutricionais do solo no cultivo da cana. No entanto, estudos ambientais destacam que esta alternativa traz efeitos negativos sobre os meios receptores (água e solo), condição que abre a perspectiva para exploração de usos alternativos dessas substâncias. Este estudo se propôs a contribuir para o tema ao avaliar de forma sistêmica o desempenho ambiental de duas alternativas de reaproveitamento de vinhaça: (i) reuso no campo em processos de fertirrigação, alternativa consolidada no Brasil, e (ii) reuso da fração líquida da vinhaça em etapas diversas do processo industrial de obtenção de etanol. Em qualquer das situações fez-se uso da técnica de Avaliação de Ciclo de Vida - ACV para proceder tal verificação. A análise ambiental da prática de reuso de vinhaça e torta para fertirrigação foi conduzida a partir da comparação de cenários que consideraram a forma de suprimento de nutrientes para a cana e o método de colheita. A avaliação de impactos ocorreu em dois níveis: quanto ao consumo de recursos, a partir de Primary Energy Demand (PED); e em termos de emissões para o ambiente por meio da elaboração do Perfil Ambiental. Uma Análise de Sensibilidade foi também realizada para verificar o efeito de oscilações dos teores de Nitrogênio (N), Fósforo (P) e Potássio (K) na composição da vinhaça sobre os resultados obtidos, caso da primeira alternativa. Concluiu-se para esse caso que a substituição parcial de fertilizantes químicos por vinhaça traz aumento da Demanda de Energia Primária global para ambos os métodos de colheita. Em termos de Perfil Ambiental, a comparação entre cenários das mesmas práticas de manejo mostrou que a troca de adubos por vinhaça e torta é positiva para o desempenho ambiental do etanol por reduzir impactos quanto a Mudanças Climáticas (CC), Acidificação Terrestre (TA) e Toxicidade Humana (HT). Por outro lado, o tratamento de vinhaça para reposição de água na etapa industrial resultou em aumento global das contribuições para as categorias acima mencionadas além de incrementos para Eutrofização de água doce (FEut) e Ecotoxicidade de água doce (FEC), a despeito de ser constatada a redução de 45% quanto a Depleção de água (WD). Os aumentos no impacto se deveram principalmente aos efeitos negativos causados durante a produção do CaO usado no processo de tratamento da vinhaça. No entanto, a substituição deste insumo por NaOH só representou melhora em termos de CC. Pode-se concluir que a reutilização de vinhaça e de torta de filtro como complemento nutricional para o cultivo de cana-de-açúcar resultou em uma alternativa mais adequada de reaproveitamento do que o se este fluído fosse reutilizado para suprir parte da demanda hídrica de processo, mesmo quando o consumo de água na etapa industrial tenha inexoravelmente se reduzido a partir da implantação dessa medida. / The production of ethanol from consecrated alcohol chemistry routes generates waste materials with reuse potential in other productive sectors as in the alcohol production cycle. This is the case of filter cake and vinasse. Vinasse, in particular, is often returned to the field in order to adjust soil nutrient levels in the cultivation of sugarcane. However, environmental studies highlight that this alternative brings negative effects on the receiving bodies (water and soil), condition that opens the prospect for the exploration of alternative uses of these substances. This study aimed to contribute to the topic by evaluating systemically the environmental performance of two vinasse recycling alternatives: (i) reuse in the sugarcane fields in fertigation processes, consolidated alternative in Brazil, and (ii) reuse of the vinasse liquid fraction in various stages of the ethanol production process. In either situation the Life Cycle Assessment Technique - LCA was used to carry out such verification. The environmental analysis of vinasse and filter cake reuse for fertigation was conducted based on the comparison of scenarios that considered the form of nutrient supply for sugarcane crops, and the harvesting methods. Impact Assessment took place on two levels: as for resource consumption from Primary Energy Demand (PED); and in terms of emissions into the environment through the elaboration of the Environmental Profile. A sensitivity analysis was also performed to evaluate the effects of fluctuations of N, P and K contents in the composition of vinasse on the results obtained, case of the first alternative. It was concluded in this case that the partial substitution of chemical fertilizers by vinasse, led to an increase in the global Primary Energy Demand for both harvesting methods. In terms of the Environmental Profile, the comparison between scenarios with the same management practices showed that replacing chemical fertilizers with vinasse and filter cake is positive for the environmental performance of ethanol since it reduces Climate Change (CC), Terrestrial Acidification (TA) and Human Toxicity (HT) impacts. Moreover, treatment of vinasse for water replacement in the industrial stage resulted in global increases for the mentioned categories as well as increments for Freshwater Eutrophication (FEut) and Freshwater Ecotoxicity (FEC), despite being detected a reduction of 45% for WD. Impact increases were due primarily to the negative effects caused during the production of CaO used during the vinasse treatment process. However, the replacement of this input by NaOH represented improvement only in terms of CC. It can be concluded that the use of vinasse and filter cake as a nutritional supplement for sugarcane cultivation resulted in a more adequate alternative for reuse than if the fluid were reused to supply part of the water process demand, even when the water consumption in the industrial stage has inexorably been reduced since the implementation of this measure.

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