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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.
71

LIFE CYCLE ASSESSMENT OF HYDROGEN PRODUCTION FROM CANADIAN BIOMASS USING FORMIC ACID AS AN ENERGY CARRIER FOR TRANS-ATLANTIC ENERGY EXPORT

Tabari, Amir January 2024 (has links)
The importance of Hydrogen (H2) in current global energy systems is undeniable. Moving from the energy systems depending on fossil fuel to energy systems that are carbon-free is a necessity, thus solutions such as hydrogen economy is required. Especially after recent geopolitical challenges in Europe which could make the energy acquisition a crucial problem. Liquid organic hydrogen carriers (LOHC) are applicable pathways for transitioning H2 into energy and to avoid the storage and transportation limitations of gaseous and liquid H2. Formic acid (FA) is an attractive alternative for such purposes due to its minimal level of toxicity and its significant volumetric storage capacity for H2. In this study, a Life cycle assessment (LCA) of the supply chain involving the Trans-Atlantic export of energy from Canada to Germany is conducted using formic acid as a LOHC and OxFA process to convert biomass to formic acid. The environmental impacts of all units and processes involved in this supply chain are examined, and the results are compared against other traditional systems for hydrogen production. A sensitivity analysis was also performed to recognize the crucial contributors and assess the processes and units that impose considerable influence on the overall environmental impact. / Thesis / Master of Applied Science (MASc) / Hydrogen (H2) plays a crucial role in transitioning from fossil fuel-based to carbon-free energy systems, a shift highlighted by recent geopolitical challenges in Europe. Liquid organic hydrogen carriers (LOHC) offer a solution for hydrogen storage and transport issues associated with its gaseous and liquid states. Formic acid (FA) is particularly promising as a LOHC due to its low toxicity and high hydrogen storage capacity. This study conducts a Life Cycle Assessment (LCA) of a supply chain that uses formic acid to export energy from Canada to Germany, involving the OxFA process for converting biomass to formic acid. The environmental impacts of all processes in this supply chain are evaluated and compared with traditional hydrogen production methods. Additionally, a sensitivity analysis identifies key contributors and assesses their impact on the overall environmental footprint.
72

Biochar amendment as a tool for improving soil health and carbon sequestration in agro-ecosystems

Drew, Sophia Eliza 14 September 2022 (has links)
Conventional farming practices and land-use conversions drive carbon out of soil and into the atmosphere, where it contributes to climate change. Biochar, a soil amendment produced by pyrolyzing organic feedstocks under low-oxygen conditions, is a promising tool to restore soil carbon and draw down atmospheric carbon dioxide. Biochar has received considerable attention from scientists, growers, and environmentalists in the last 20 years, but there is still a gap between academic research and practical recommendations on biochar production and application that are relevant to small-scale growers. Here I present the results from two complementary studies that demonstrate the utility of local-scale biochar systems and provide some recommendations for those looking to work with biochar. The first study sought to determine the impact of biochar amendments on soil carbon and nutrient retention on three working farms across a variety of soil types, cropping systems, and climates in the United States. The effect of biochar amendment depended on initial soil characteristics and the properties of the biochar applied. Biochar amendments increased soil carbon in all three sites and increased soil nitrogen at two of the three. In this study pyrolysis conditions appeared to be as important as local soils and climate influences on the efficacy of biochar treatments. The second study was a life cycle assessment using SimaPro software to quantify the carbon balance and global warming potential of biochar produced from three local feedstocks (softwood, hardwood, and hay) applied to pasture soils in Southwest Virginia. Feedstock type, pyrolysis gas yield, and transportation distance significantly contributed to variation in the carbon balance of each agro-ecosystem. Biochar made from softwood lumber scraps performed best, with the highest net carbon storage and lowest global warming potential, followed by biochar made from hardwood scraps. Hay biochar performed worst, with positive carbon emissions (i.e., more carbon released than stored over its life cycle) in most scenarios tested, mainly because of its low biochar yield and the carbon emissions associated with agronomic production and transportation. Together these studies demonstrate the potential of local biochar systems to improve both soil health and carbon sequestration, and reinforce how important it is to know the characteristics of the soil and the production history and properties of the biochar being applied in order to meet soil health and carbon sequestration goals. / Master of Science / Conventional farming practices break down organic material in the soil, which decreases the capacity of soils to sustain crop growth and contributes to climate change as the soil releases carbon dioxide and other greenhouse gasses into the atmosphere. Biochar, or charcoal that is deliberately incorporated into soil, is gaining popularity among farmers, gardeners, and climate scientists for its ability to improve soil health and draw carbon out of the atmosphere to create stable long-term pools of carbon underground. Unfortunately, much of the research on biochar does not translate easily into recommendations for growers and land-managers to make and use biochar. Here I discuss the results from two studies examining the effect of biochar on soil health and carbon sequestration on local scales. In the first experiment I analyzed soil samples shared by farmers in New Mexico, Minnesota and Virginia who applied locally-sourced biochar to their soils. I found that the initial characteristics of the soil and of the biochar affected how the biochar application changed agriculturally-relevant soil properties. In general, biochar improved soil carbon and nitrogen levels, had mixed effects on soil pH depending on the biochar's pH, and had no effect on electrical conductivity (a measure of soil salinity). The second study was a life cycle assessment that quantified and compared greenhouse gas emissions of three different types of biochar, from feedstock harvest to biochar application to soil. I found that the type of feedstock used to make biochar, the amount of gas emitted during the conversion process, and the distance the feedstocks and biochar were transported all played a role in the overall carbon balance of the life cycle. The biochar made from softwood scraps performed best from a carbon storage perspective, followed by biochar made from hardwood. These two biochars tended to return more carbon to the soil than they emitted over their life cycle. The biochar made from hay performed worst, and emitted more carbon than it stored in most of the scenarios I tested. Together these studies show the potential of local biochar systems to improve both soil health and carbon sequestration and reinforce how important it is to be familiar with the soil and the production history and properties of the biochar being applied in order to meet soil health and carbon sequestration goals.
73

Sustainability assessment of active packaging incorporating nanomaterials

Zhang, Hai 16 November 2017 (has links)
Tesis por compendio / Packaging plays an important role in ensuring food safety and quality. The development antimicrobial packaging enables actively inhibiting/killing the spoilage microorganisms, and thus extending food product's shelf life. Generally, 50% shelf life extension is possible. The interest for using metallic nanoparticles in active packaging derives from its superior antimicrobial efficacy and no negative impact on the food sensory properties. In this thesis, the packaging material of concern is a PLA (Polylactic Acid) coated paper incorporating zinc oxide nanoparticles (ZnO NPs) in the coating layer. The material was characterized and its antimicrobial activity was evaluated. The SEM images show that the nanoparticles were homogenously distributed across the surface thanks to its surface modification. Antimicrobial assay indicates that the active material was effective in inactivating E. coli and S. aureus. Furthermore, E. coli was found to be more susceptible to this type of agent, showing 3.14 log reduction for 0.5 wt% agent loading in the PLA coating layer. This result was compared across the publications using the same agent for treating both Gram-positive and Gram-negative microorganisms. The discrepancy between the results can be explained by the fact that ZnO nanoparticles have multiple action mechanisms, and different antimicrobial testing methods may activate part of the action mechanisms. On the other hand, recyclability is regarded as an important attribute for paper-based packaging material, as it enables to conserve the resources and reduce the environmental impacts. Accordingly, when it comes to the nano-enabled paper packaging material, recyclability should be maintained. In this case, a recyclability test was carried out in a lab-scale paper recycling line. The protocol was based on a method adapted from the ATICELCA MC501-13, which enabled to recover over 99% of the solids material. The mass balance result indicates that 86%-91% zinc oxide nanoparticles ended up in the rejected material stream, mostly embedded within the polymer coating; whereas 7%-16% nanoparticles ended up in the accepted material stream. Besides, the tensile strength of the recycled handsheets suggests that the nano-enabled coating had no negative impacts on the recovered fibre quality. Active packaging plays a positive role in reducing food losses. If food and packaging are considered as a whole system, its overall environmental impact can be justified by incorporating the food loss reduction due to the application of active packaging. The LCA calculation shows that a breakeven point can be easily achieved for the case of red meat products of high environmental impact. / El envase juega un papel importante asegurando la seguridad y calidad de los alimentos. El desarrollo de envases activos, especialmente envase antimicrobiano, permite inhibir o matar los microorganismos causantes del deterioro de los alimentos, alargando por tanto su vida útil. De forma general es posible extender la vida útil de los alimentos en un 50%. El interés por el uso de nanopartículas metálicas en el envasado activo se deriva de su gran efectividad antimicrobiana sin causar un efecto negativo en sus propiedades sensoriales. En la presente tesis, se ha desarrollado un papel recubierto de PLA (ácido poliláctico) con nanopartículas de óxido de zinc (ZnO NPs) incorporadas en la capa de recubrimiento. Se ha caracterizado el material y se ha evaluado su capacidad antimicrobiana. Las imágenes obtenidas mediante SEM muestran que las nanopartículas fueron distribuidas a lo largo de la superficie gracias a su modificación. Los ensayos de efectividad antimicrobiana indicaron una actividad del material frente a E. coli y a S. aureus. Además, E. coli resultó ser más susceptible a este agente activo incorporado al 0.5 % en peso en el recubrimiento de PLA, mostrando una reducción de 3.14 log. Este resultado fue comparado con publicaciones donde se emplearon los mismos agentes activos para frente a microorganismos Gram-positivos y Gram-negativos. Las discrepancias encontradas entre los resultados pueden deberse a que las nanopartículas de ZnO tienen múltiples mecanismos de acción, y los diferentes métodos de ensayo poder estimular parte de estos mecanismos. Por otra parte, el reciclado juega un importante papel en la conservación de los recursos y en la reducción de los impactos medioambientales. Por tanto, cuando se trata de un material de envase de papel con sustancias de tamaño nano, el reciclado debe tratarse adecuadamente. El ensayo de reciclabilidad fue llevado a cabo a escala laboratorio en una línea de reciclado de papel. El protocolo de ensayo se basó en el método adaptado de ATICELCA MC501-13, permitiendo una recuperación del 99% de material sólidos. Los resultados del balance de materia indicaron que el 86%-91% de las nanopartículas de óxido de zinc llegaron al flujo de material de rechazo, principalmente mezclado en el recubrimiento polimérico. Además, los resultados de tracción de las láminas recicladas sugieren que el recubrimiento con partículas nano no tiene un efecto negativo sobre la calidad de la fibra recuperada. El envase activo juega un papel positivo en la reducción de los residuos alimentarios. Como resultado del uso del envase activo, considerando el envase y el alimento como un todo, el impacto ambiental sobre este sistema completo puede ser compensado por la reducción de pérdidas de alimentos. El cálculo LCA muestra que el punto de equilibrio se puede conseguir fácilmente en el caso de productos de carne roja de elevado impacto ambiental. / L'envàs té un paper prou important en la seguretat i la qualitat del aliments. El desenvolupament dels envasos actius, especialment l'envàs antimicrobià, el qual permeteix l'inhibició o mort dels microorganismes que produeixen el deteriorament dels aliments i, per tant, allargant la seua vida útil. De manera general, es possible l'allargament de la vida útil dels aliments en un 50%. L'interès per la utilització de nanopartícules metàl·liques en l'envasat actiu es deriva de la seua gran efectivitat antimicrobiana sense produir un efecte negatiu en les seus propietats sensorials. En aquesta present tesis, s'ha desenvolupat un paper recobert de PLA (àcid polilàctic) amb nanopartícules d'òxid de zinc (ZnO NPs) incorporades a la capa de recobriment. S'ha caracteritzat el material i s'ha avaluat la seua capacitat antimicrobiana. Les imatges obtingudes per mitjà del SEM mostren que les nanopartícules foren distribuïdes en tota la superfície gràcies a la seua modificació. Els assajos d'efectivitat antimicrobiana varen indicar una activitat del material front a E.coli i a S. aureus. A més, E. coli va resultar ser més susceptible a aquest agent actiu incorporat al 0.5 % en pes en el recobriment de PLA, mostrant una reducció de 3.14 log. Aquest resultat va ser comparat amb publicacions on es van emprar els mateixos agents actius front a microorganismes Gram-positiu i Gram-negatiu. Les discrepàncies trobades entre els resultats poden deure's a que les nanopartícules de ZnO tenen diversos mecanismes d'acció, i els diferents mètodes d'assaig poder estimular part d'aquestes mecanismes. Per altra banda, el reciclatge també té un paper important en la conservació dels recursos i en la reducció dels impactes mediambientals. Per tant, quan es tracta d'un material d'envàs de paper amb substàncies de la grandària 'nano', el reciclatge ha de tractar-se adequadament. El assaig de reciclabilitat va ser dut a terme a escala de laboratori en una línia de reciclatge de paper. El protocol de l'assaig es va basar en el mètode adaptat d'ATICELCA MC501-13, permetent una recuperació del 99% del material sòlid. Els resultats del balanç de matèria van indicar que el 86-91% de les nanopartícules d'òxid de zinc varen arribar al fluix material de rebuig, principalment mesclat en el recobriment polimèric. A més, els resultats de tracció de les làmines reciclades suggereixen que el recobriment amb nanopartícules nano no tenen un efecte negatiu sobre la qualitat de la fibra recuperada. L'envàs actiu juga un paper positiu en la reducció dels residus alimentaris. Com a resultat de l'ús de l'envàs actiu, considerant l'envàs i l'aliment com un tot conjunt, l'impacte ambiental sobre aquest sistema complet pot ser compensat per la reducció de pèrdues d'aliments. El càlcul LCA mostra que el punt d'equilibri es pot aconseguir fàcilment en el cas de productes de carn roja d'elevat impacte ambiental. / Zhang, H. (2016). Sustainability assessment of active packaging incorporating nanomaterials [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/75348 / Compendio
74

A Framework for Holistic Life Cycle Cost Analysis for Drinking Water Pipelines

Khurana, Mayank 18 July 2017 (has links)
Life Cycle Cost Analysis (LCCA) forms an important part of asset management practices and provides an informed decision support. The holistic nature of LCCA includes life cycle assessment (LCA) as an important component alongside economic life cycle cost analysis. The drinking water industry is right now lacking a reliable cost data structure which will ensure that all the utilities capture the same set of cost data. Also, models and tools currently available in the academia and industry are purely deterministic in nature and do not cater to uncertainty in the data. This study provides a framework for a holistic life cycle cost analysis tool which will help drinking water utilities to prioritize the activities and optimize the cost spending of the utility. The methodology includes the development of a cost data structure, a life cycle cost analysis and a life cycle assessment model in the form of an excel spreadsheet. The LCCA model has the capability to compare different pipe materials, installation, condition assessment, rehabilitation and replacement technologies. Whereas, LCA model can compare different pipe materials based on greenhouse gas emissions calculations. The final step of the methodology includes piloting the model with data from utility A. The analysis has been shown in the form of three case studies - comparison of two pipe materials, two pipe installation technologies and two pipe rehabilitation technologies. The case studies provide results in the form of comparison of total life cycle costs for different alternatives and hence a better alternative can be chosen. / Master of Science / The drinking water industry is right now lacking a reliable cost data structure which will ensure that all the utilities capture the same set of cost data. Also, models and tools currently available in the academia and industry do not cater to uncertainty in the data. This study provides a framework for a holistic life cycle cost analysis tool which will help drinking water utilities to prioritize the activities and optimize the cost spending of the utility. The methodology includes the development of a cost data structure, a life cycle cost analysis and a life cycle assessment model in the form of an excel spreadsheet. The LCCA model has the capability to compare different pipe materials, installation, condition assessment, rehabilitation and replacement technologies. Whereas, LCA model can compare different pipe materials based on greenhouse gas emissions calculations. The final step of the methodology includes piloting the model with data from utility A. The analysis has been shown in the form of three case studies - comparison of two pipe materials, two pipe installation technologies and two pipe rehabilitation technologies. The case studies provide results in the form of comparison of total life cycle costs for different alternatives and hence a better alternative can be chosen.
75

A holistic life cycle sustainability assessment for bioeconomy regions: Linking regional assessments, stakeholders and global goals

Zeug, Walther 21 June 2024 (has links)
Since about 2015 the social, environmental and economic risks and chances of the bioeconomy and economy in general are becoming increasingly the subject of applied sustainability assessments. Under a bioeconomy, a variety of industrial metabolisms, strategies and visions on substituting fossil resources by renewables and hereto associated societal transformations is formulated, characterized as regional bioeconomy if most foreground activities take place in a specific region. Based on the life cycle assessment (LCA) methodology, further social and economic LCA approaches were developed in previous research whereby life cycle sustainability assessment (LCSA) aims to combine or integrate the evaluation of social, environmental and economic effects. In this early stage of rudimentary and combinatory LCSA development, the research questions of this work are to develop a transdisciplinary framework for integrated LCSA for regional stakeholders to assess ecological, economic and social sustainability in one harmonized method, as well as to implement, apply and validate it by two regional case studies. Therefore, i) the understandings of sustainability and approaches of sustainability assessment in LCA are transdisciplinary reflected and developed, ii) a systemic framework of the important aspects of such assessments is structured by a series of stakeholder workshops, iii) the methods and indicators from existing LCA approaches as well as from bioeconomy monitoring systems are selected, identified and allocated to a sustainability concept of holistic and integrated LCSA (HILCSA), iv) databases for the life cycle inventory and methods for life cycle impact assessment are implemented in a software, as well as v) the model and method is applied and validated in two case studies on laminated veneer lumber production and production of biofuels in central Germany. Based on previous research, the dissertation provides a theoretically well based and practically applicable framework for integrated life cycle sustainability assessment, an applicable indicator set for regional (product & territorial) bioeconomy assessment, an integration of life cycle impact assessment methods as well as their comprehensive interpretation. Thereby, LCSA is able to identify the contribution of regional bioeconomy product systems to 14 out of 17 Sustainable Development Goals in terms of planetary boundaries, a sustainable economy and societal needs. The presented results on material and energetic use cases of biomass show that integrated assessments are able to deliver a broad and comprehensive analysis of impacts to identify synergies, trade-offs and hot spots of regional bioeconomy. Compared to existing LCA and LCSA methodologies, the added value of the HILCSA methodology is its integrated and holistic character, which [1] allows consistent and comparable data on social, ecological, and economic indicators, [2] identifies synergies and trade-offs between different aspects and SDGs, [3] traces down impacts to regions in the fore-and background systems, [4] as well as allocates and aggregates them to the SDGs to make complexity communicable. Additionally, HILCSA takes social sciences and political economy into account from beginning to interpretation and discussion of results, relating to social, environmental, and economic impacts not only to technologies but also to societal, economic, and political questions.:Part I Overarching Introduction 1 1. Introduction 2 2. State of the Art 3 2.1 Sustainability Concepts and Frameworks in the Context of BE and the Role of Stakeholder Participation 3 2.2 LCA and LCSA Approaches for BE Regions 5 2.3 Inter-, Transdisciplinarity and Political Economy for Holistic Sustainability Assessment 7 2.4 Research Gaps to be addressed 8 3. Research Objectives 9 4. Methods 10 4.1 Stakeholder Expectations of the BE in Germany and Relevance of SDGs for Sustainability Assessments 10 4.2 Theoretical and Conceptual Considerations on BE, Sustainability and its Assessment for a Holistic and Integrated Framework for LCSA (HILCSA) 11 4.3 Criteria and Aspects for Implementation and Operationalization of HILCSA for BE Regions 11 4.4 Lessons Learned from Application and Validation of HILCSA in Case Studies and Results on Risks and Chances of a BE Transformation 13 5. Results 14 5.1 Stakeholder Participation in BE Monitoring and Assessment 14 5.1.1 Relevances, Interests and Perceptions 14 5.1.2 Narratives and Visions 17 5.2 Theoretical and Conceptual Implications from a Transdisciplinary Perspective on Sustainability Frameworks and Assessments 19 5.2.1 The Three Pillar Approach and additive LCSA 19 5.2.2 Introduction of Societal Relations to Nature in Sustainability Assessment and LCA 21 5.2.3 Societal-Ecological Transformation and the role of LCSA 21 5.3 Operationalization and Implementation of Holistic and Integrated LCSA (HILCSA) for BE Regions 23 5.3.1 Sustainability Concept and LCA Framework for HILCSA 23 5.3.2 Initial LCI and LCIA for HILCSA 25 5.4 Application and Validation of HILCSA in Case Studies and Results on Risks and Chances of a BE Transformation 31 5.4.1 Application of Holistic and Integrated LCSA: First Case Study on LVL Production in Central Germany 31 5.4.1.1 Goal and Scope 31 5.4.1.2 Life Cycle Inventory 33 5.4.1.3 Life Cycle Impact Assessment 34 5.4.1.4 Interpretation 35 5.4.2 Application of Holistic and Integrated LCSA: Second Case Study on prospective biomass to liquid production in Germany 36 5.4.2.1 Goal and Scope 36 5.4.2.2 Life Cycle Inventory 38 5.4.2.3 Life Cycle Impact Assessment 39 5.4.2.4 Interpretation 41 6. Conclusion and Outlook 43 6.1 Stakeholder Expectations and Participation 43 6.2 Theoretical Concepts for Sustainability and Methodological Frameworks 44 6.3 Operationalization and implementation of Holistic and Integrated LCSA 45 6.4 Lessons Learned from Case Studies: Identifying Risks and Chances of Regional BE by Applying & Validating HILCSA 47 6.4.1 Risks and Chances of Regional BE in Case of LVL and BtL and Validation of HILCSA 47 6.4.2 Lessons Learned and Future HILCSA Methodology Development 48 6.5 Concluding Remarks on Political (Bio-)Economy and Transformation 52 References 54 List of Acronyms 66 List of Tables 66 List of Figures 66 Part II Publications 68
76

Avaliação consequencial do ciclo de vida: discussão e aplicação comparativa com a abordagem atribucional / Consequential life cycle assessment: discussion and comparative application with the attributional approach

Michelle Tereza Scachetti 28 April 2016 (has links)
A Avaliação do Ciclo de Vida é uma das principais técnicas de avaliação ambiental de bens e serviços e pode ser classificada em duas abordagens: atribucional e consequencial. A atribucional, caracterizada pelo uso de dados médios de ICV e de alocação de coprodutos, tem como objetivo a avaliação dos impactos ambientais de um produto do berço ao túmulo, em um sistema estático. A ACV consequencial consiste na avaliação das consequências ambientais em um sistema dinâmico, orientado por mudanças. Esta abordagem vem sendo intensamente discutida na literatura internacional, porém, no Brasil ainda se trata de um tema pouco explorado. O presente trabalho visa aprofundar a discussão entre as duas abordagens da ACV. Para isso, utilizaram-se os seguintes procedimentos metodológicos: revisão da literatura e aplicação das abordagens ao biocombustível etanol hidratado de cana-de-açúcar. Os resultados apontam que a ACV atribucional apresentou maiores cargas ambientais em todas as categorias de impacto, com principalmente nas categorias de Ecotoxicidade Aquática, Ecotoxicidade Terrestre e Depleção Abiótica. Isto se deve à subtração das cargas ambientais referentes aos produtos evitados, considerados na análise devido à expansão do sistema realizada na abordagem consequencial com a finalidade de evitar a alocação que, por sua vez, foi utilizada na abordagem atribucional. Notou-se que, em teoria, a principal diferença entre as abordagens da ACV consiste em seus distintos alinhamentos quanto à aplicação pretendida, sendo a atribucional voltada ao conhecimento dos impactos ambientais do ciclo de vida de um produto e identificação de pontos críticos no sistema, e a abordagem consequencial voltada à identificação das consequências ambientais geradas por uma mudança no sistema de produto investigado. Na prática, entretanto, foram encontradas algumas limitações que comprometeram a operacionalização do estudo consequencial, distanciando-a do seu propósito teórico. Dentre estas limitações merecem destaque: o grande número de simplificações intrínsecas ao método aplicado e a falta de transparência quanto à base de dados de background utilizada. Notou-se que a operacionalização da ACV consequencial é bastante complexa, pois despende muito tempo e recursos, principalmente na coleta e validação de informações de mercado. Portanto, reforça-se a necessidade de esforços no sentido do desenvolvimento de métodos menos subjetivos e mais sistemáticos para a abordagem consequencial além de diretrizes mais esclarecedoras explicitando as diferenças quanto ao conteúdo, contextos e formas de aplicação das abordagens atribucional e consequencial da ACV e indicando em quais situações elas podem ser complementares. / Life Cycle Assessment is one of the most used tool to asses environmental impact of goods and services. It can be classified into two approaches: attributional and consequential.Attributional LCA, characterized by the use of average data ICV and coproducts allocation is aimed at assessing the environmental impacts of a product from the cradle to the grave, in a static system. The consequential LCA is the evaluation of the environmental consequences in a dynamic system driven by changes. Both approaches have been intensively discussed in the literature in recent years, but in Brazil it is still a little discussed and explored topic. Thus, this study aims to deepen the discussion between the two LCA approaches. For this, the following methodological procedures are used: literature review and application of the approaches on hydrated bioethanol from sugarcane. The results show that the attributional LCA has higher environmental burdens in all impact categories, with greater difference with consequential in the categories of aquatic and terrestrial ecotoxicity and abiotic depletion. This is due to the subtraction of environmental charges related to avoided products, considered at the time of system expansion in consequential approach, which did not occur in attributional (where co- products were treated by means of allocation). The main differences between the approaches reflect their different alignments on the intended application, the attributional approach is mostly focused on the knowledge of the environmental impacts of the life cycle of a product and identification of improvement points to the system, while the consequential approach aims to verify potential environmental consequences generated by the change in product system investigated. In practice, however, it was observed that the consequential LCA results should be interpreted with great caution due to the fact that the application has brought a large number of limitations, such as: great number of simplifications of the method applied, consideration of standard assumptions when the lack of information for the collection of data and lack of transparency as to the basis of background data used. Moreover, its implementation is still quite complex, requiring much time and resources to collect data and market information. Therefore, we reinforce what has already been established through the literature review: efforts are needed towards the development of less subjective methods and more systematic for consequential approach as well as more enlightening guidelines explaining the differences in the content, context and application forms of attributional and consequential LCA approaches.
77

Avaliação consequencial do ciclo de vida: discussão e aplicação comparativa com a abordagem atribucional / Consequential life cycle assessment: discussion and comparative application with the attributional approach

Scachetti, Michelle Tereza 28 April 2016 (has links)
A Avaliação do Ciclo de Vida é uma das principais técnicas de avaliação ambiental de bens e serviços e pode ser classificada em duas abordagens: atribucional e consequencial. A atribucional, caracterizada pelo uso de dados médios de ICV e de alocação de coprodutos, tem como objetivo a avaliação dos impactos ambientais de um produto do berço ao túmulo, em um sistema estático. A ACV consequencial consiste na avaliação das consequências ambientais em um sistema dinâmico, orientado por mudanças. Esta abordagem vem sendo intensamente discutida na literatura internacional, porém, no Brasil ainda se trata de um tema pouco explorado. O presente trabalho visa aprofundar a discussão entre as duas abordagens da ACV. Para isso, utilizaram-se os seguintes procedimentos metodológicos: revisão da literatura e aplicação das abordagens ao biocombustível etanol hidratado de cana-de-açúcar. Os resultados apontam que a ACV atribucional apresentou maiores cargas ambientais em todas as categorias de impacto, com principalmente nas categorias de Ecotoxicidade Aquática, Ecotoxicidade Terrestre e Depleção Abiótica. Isto se deve à subtração das cargas ambientais referentes aos produtos evitados, considerados na análise devido à expansão do sistema realizada na abordagem consequencial com a finalidade de evitar a alocação que, por sua vez, foi utilizada na abordagem atribucional. Notou-se que, em teoria, a principal diferença entre as abordagens da ACV consiste em seus distintos alinhamentos quanto à aplicação pretendida, sendo a atribucional voltada ao conhecimento dos impactos ambientais do ciclo de vida de um produto e identificação de pontos críticos no sistema, e a abordagem consequencial voltada à identificação das consequências ambientais geradas por uma mudança no sistema de produto investigado. Na prática, entretanto, foram encontradas algumas limitações que comprometeram a operacionalização do estudo consequencial, distanciando-a do seu propósito teórico. Dentre estas limitações merecem destaque: o grande número de simplificações intrínsecas ao método aplicado e a falta de transparência quanto à base de dados de background utilizada. Notou-se que a operacionalização da ACV consequencial é bastante complexa, pois despende muito tempo e recursos, principalmente na coleta e validação de informações de mercado. Portanto, reforça-se a necessidade de esforços no sentido do desenvolvimento de métodos menos subjetivos e mais sistemáticos para a abordagem consequencial além de diretrizes mais esclarecedoras explicitando as diferenças quanto ao conteúdo, contextos e formas de aplicação das abordagens atribucional e consequencial da ACV e indicando em quais situações elas podem ser complementares. / Life Cycle Assessment is one of the most used tool to asses environmental impact of goods and services. It can be classified into two approaches: attributional and consequential.Attributional LCA, characterized by the use of average data ICV and coproducts allocation is aimed at assessing the environmental impacts of a product from the cradle to the grave, in a static system. The consequential LCA is the evaluation of the environmental consequences in a dynamic system driven by changes. Both approaches have been intensively discussed in the literature in recent years, but in Brazil it is still a little discussed and explored topic. Thus, this study aims to deepen the discussion between the two LCA approaches. For this, the following methodological procedures are used: literature review and application of the approaches on hydrated bioethanol from sugarcane. The results show that the attributional LCA has higher environmental burdens in all impact categories, with greater difference with consequential in the categories of aquatic and terrestrial ecotoxicity and abiotic depletion. This is due to the subtraction of environmental charges related to avoided products, considered at the time of system expansion in consequential approach, which did not occur in attributional (where co- products were treated by means of allocation). The main differences between the approaches reflect their different alignments on the intended application, the attributional approach is mostly focused on the knowledge of the environmental impacts of the life cycle of a product and identification of improvement points to the system, while the consequential approach aims to verify potential environmental consequences generated by the change in product system investigated. In practice, however, it was observed that the consequential LCA results should be interpreted with great caution due to the fact that the application has brought a large number of limitations, such as: great number of simplifications of the method applied, consideration of standard assumptions when the lack of information for the collection of data and lack of transparency as to the basis of background data used. Moreover, its implementation is still quite complex, requiring much time and resources to collect data and market information. Therefore, we reinforce what has already been established through the literature review: efforts are needed towards the development of less subjective methods and more systematic for consequential approach as well as more enlightening guidelines explaining the differences in the content, context and application forms of attributional and consequential LCA approaches.
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Transition of non-production facilities towards carbon-neutrality A Case Study- Volvo CE’s Customer Center

Aliahmad, Abdulhamid, Mohan, Aisiri January 2020 (has links)
Research on historical developments that lead to the establishment of global organizations for climate change has shown that the phenomenon of surface temperature is not a new topic of focus. Increased policy restrictions, brand image, fear of resource scarcity, growing market trends towards sustainability and consumer awareness are among the several external factors that have influenced the growing research in corporate transition towards carbon neutrality. The main aim of this study is to understand through data accounting of major material and energy carrier changes, how a non-production facility could transition to become a carbon-neutral facility. Therefore, an exploratory case study has been performed and conducted at Volvo CE Customer center in Eskilstuna, Sweden, with two objectives: i) to identify and quantify the customer center current footprint by mapping the main contributors to greenhouse gases emissions, and ii) to recommend specific & general measures that can mitigate the carbon footprint of the facility. Three research questions related to the facility’s current carbon footprint, measures implemented so far, and the best applied assessment method, have guided us throughout the study. The methodology has been framed to give a theoretical underpinning for understanding the project from a holistic perspective. The split of the methodology has been constructed in line with the theoretical framework that gave the foundation to the needed theories to be taken into account i.e. GHG protocol, which is the tool that has been adopted by the study to attain the desired aim, including the three scopes under the protocol which were also defined accordingly. ‘Scope 1’ has been taken into account and is a representation of direct emissions, ‘Scope 2 represents the indirect emissions, and ‘Scope 3’ (according to the GHG protocol) takes into account the rest of the indirect emissions arranged into 15 categories, from which applicable to our study were 4 categories (1, 3, 4 and 6). The results showed that during the base year (2019) the highest user within Scope 1 was diesel, followed by HVO, and under Scope 2, The results from Scope 1 and 2, together with the results of Scope 3 category, were analyzed using the attributional LCA approach recommended by the GHG protocol to calculate their contribution to the customer centers’ total carbon footprint. It was found that Scope 1 stands for 128.52 t CO₂-eq while Scope 2 stands only for 1.16 t CO₂-eq and finally Scope 3 stands for most of the emissions with 3719 t CO₂-eq. It has been found that in 2019, the customer center has saved 101.05 tonnes of GHG by implementing measures, such as switching from using Diesel to HVO and switching from the mixed electricity to the renewable ones, according to the attributional perspective presented in the GHG protocol. However, different results were found when these values were discussed and analyzed from the consequential perspective, since this perspective analyses the effects of the implemented measures on the global emission level. This concluded that implementation of conservation and efficiency measures must take priority before switching to higher priced renewables. Thus, the resulting carbon neutrality will be consequentially safer. The recommendations stated in this study also follows the same principle “Conserve before investing”. Suggestions and recommendations outlined in the study for future implementation approach carbon neutrality as a strategy and not a burden, helping the customer neutral achieve the goal in an Environment, Economic and Socially sustainable manner.
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Life Cycle Assessment for Improving Sustainability of Aquaculture and Aquaponics

April Janai Arbour (17583837) 09 December 2023 (has links)
<p dir="ltr">Controlled environment agriculture (CEA) is a practice of food production under optimized conditions to intensify production yield, and thus has potential for addressing food security for a growing population. Aquaculture and aquaponics are two types of CEA that can produce aquatic animals along with plants using non-arable lands and lower inputs of water and nutrients. However, their operations have high energy consumption and generate considerable nutrient-rich sludge and wastewater, making their environmental performance an emerging research focus. This thesis quantitively analyzed the environmental sustainability of aquaponics and aquaculture production using life cycle assessment (LCA).</p><p dir="ltr">The LCA on aquaponics evaluated a marine aquaponics production system that grew shrimp, red orache, minutina and okahajiki, and analyzed the effect of salinity, C/N ratio, and shrimp-to-plant stocking density. The grow-out stage accounted for over 90% of total environmental impacts with electricity use as the predominant contributor. The marine aquaponic production exhibited best environmental performance when operated at low salinity (10 ppt), and high C/N ratio (15) and stocking density (5:1), which can be further improved by 95–99% via the use of wind power as electricity source. Additionally, variation in the prices of aquaponic products was found to improve the system’s environmental impacts by up to 8%.</p><p dir="ltr">The aquaculture LCA focused on shrimp recirculating aquaculture systems (RAS) and evaluated the environmental feasibility of microalgae-based wastewater treatment. Microalgae treatment effectively removed 74% of phosphate in RAS wastewater and thus reduced the freshwater eutrophication potential by 55%. However, its remediation performance was inferior to activated sludge treatment due to different operation scales. Electricity was the principal hotspot of microalgae treatment and made up over 99% of all the environmental impacts, which can be considerably decreased by reducing coal use in the electricity supply. Three utilization pathways for algal biomass (feed ingredient, biodiesel and biogas) were investigated; however, only biogas production was found to show environmental benefits to marine eutrophication remediation owing to the low biomass quantity produced.</p><p dir="ltr">While <a href="" target="_blank">aquaculture and aquaponics</a> play important roles in meeting the globally growing demand for seafood, this thesis provides valuable life cycle inventory data for these fields. Moreover, the LCA models developed in this thesis are useful decision-making tools for aquaculture and aquaponic producers to adapt farming practices with lower environmental footprint.</p>
80

CAD-Integrated Life Cycle Assessment in Product Development : Evaluation in a Technical Development Context

Hultgren, Petrus, Smärgel, Pontus January 2023 (has links)
In order to reduce the environmental footprint of products, companies turn to Eco-design and associated tools. Life cycle assessment (LCA) is a holistic and quantitative tool that is widely accepted in companies, but it is too extensive to apply in product development; as an alternative, simplified versions are more suitable. By utilising CAD models of components, material data and a database, weight can be calculated and LCA data estimated. This thesis aims to evaluate the feasibility of utilising CAD-integrated LCA software in product development process and explore the barriers in doing so. A case study was conducted to evaluate the software Sustainable Innovation Intelligence by thoroughly describing the tool, the database used as well as the product life cycle management (PLM) system used. Two research questions have been formulated regarding the barriers and to what extent they can be overcome using the new CAD-integrated tool. The first one is answered by a literature review, where 22 barriers were identified and related to different sociotechnical levels, while the second is answered by using pattern matching following the case study. The evaluation covers human and technical aspects of the tool itself, what is required by the practitioner, as well as additional aspects to consider when implementing the tool in a company. The final result shows that 11 of the barriers are to some extent being overcome by the tool. While showing promise, the novelty of the software makes it immature and lacking full functionality, while requiring a lot of the practitioner in terms of LCA specific knowledge.

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