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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.
101

Proposition d'une méthode d'allocation par répartition paramètre-dépendant pour l'Analyse du Cycle de Vie des produits déchet-sourcés - Application aux fertilisants phosphatés boue-sourcés / Definition of a parameter-dependent allocation methodology for Life Cycle Assessment of waste-based products – Application to sludge-based phosphate fertilizers

Pradel, Marilys 26 October 2017 (has links)
Les activités humaines produisent des eaux usées dont le traitement génère des boues d’épuration urbaines. Ces boues font l’objet de recherches visant à les transformer en produits à forte valeur ajoutée. Elles pourraient ainsi passer d’un statut de déchet fatal au statut de coproduit attendu à l’issue de l’épuration des eaux. Ce changement de paradigme a des conséquences sur l’évaluation environnementale par Analyse du Cycle de Vie (ACV) des produits « boue-sourcés ». La boue devient un coproduit attendu de la station de traitement des eaux et la charge environnementale liée à leur production doit pouvoir être répartie entre coproduits au moyen d’un facteur d’allocation. Cette thèse propose une construction mathématique de ce facteur d’allocation en combinant des paramètres « procédés » et « produits », intégrant de facto les relations causales entre conduite du procédé et obtention des produits, reflétant la réalité technologique du procédé. La résultante se présente sous la forme d’une matrice dont chaque élément associe, pour chaque donnée d’inventaire, un facteur d’allocation à chacun des coproduits générés. Appliquée à la production de fertilisants phosphatés boue-sourcés, l’ACV réalisée a permis de mettre en lumière la contribution majeure de l’étape de production par rapport aux étapes de traitement et valorisation de la boue. Cette méthodologie de construction d’un facteur d’allocation permet toutefois d’attribuer une charge environnementale à chacun des coproduits d’un système de production indivisible et peut également être utilisée de manière pertinente lors de l’évaluation environnementale des procédés de séparation de nature thermique, chimique ou physique. / Human activities produce wastewater that generates sludge, a waste recycled on agricultural soils or for energy recovery. Extensive research is currently undergone on sludge to develop processes that can convert it into products with high-added value. In this context, sludge could move from a fatal waste status to the status of an expected co-product of wastewater treatment. This paradigm shift has implications for the assessment of environmental impacts of "sludge-based" materials with Life Cycle Assessment. Indeed, sludge becomes an expected co-product from the wastewater treatment plant and the environmental burden of their production must be distributed among co-products by means of an allocation factor. This thesis aims at defining a mathematical construction of this allocation factor by combining process- and product-related parameters, integrating de facto the causal relationships between process operations and products generation and the technological reality of the process. The result is a matrix of which each element associates, for each inventory data, an allocation factor to each of the generated co-products. Applied to the production of sludge-based phosphate fertilizers, LCA highlights the major contribution of the production stage compared to the stages of treatment and recovery of the sludge. Nevertheless, the method developed within this thesis to allocate an environmental load to each co-products of an indivisible production system paves the way for a more coherent environmental assessment of waste-based products. This methodology can also be used effectively in the environmental assessment of thermal, chemical or physical separation processes.
102

Integração de indicadores de desempenho técnico-funcional, ambiental e econômico de sistemas estruturais verticais em concreto / Integration of technical-functional, environmental and economic performance indicators of concrete vertical structural systems

Oliveira, Flávia Ruschi Mendes de, 1957- 12 November 2013 (has links)
Orientador: Vanessa Gomes da Silva / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-24T06:07:43Z (GMT). No. of bitstreams: 1 Oliveira_FlaviaRuschiMendesde_D.pdf: 3494903 bytes, checksum: a620337e4a546dd5a31d11a4ec3f1919 (MD5) Previous issue date: 2013 / Resumo: Pesquisas sobre novas gerações de sistemas de avaliação de edificações sugerem que o nível de sustentabilidade seja sempre avaliado por indicadores. Estudos de avaliação do ciclo de vida (ACV) apontam o sistema estrutural como um dos principais contribuintes para as cargas ambientais de uma edificação. Não obstante, as estruturas têm recebido atenção insuficiente nestes sistemas de avaliação. No setor de construção civil brasileiro, onde predominam edificações em concreto, dados de avaliação integrada de desempenho ambiental, econômico e social no ciclo de vida das edificações ou de seus subsistemas são, praticamente, inexistentes. Este trabalho teve por objetivo demonstrar a hipótese de que um conjunto de indicadores é capaz de integrar aspectos fundamentais de sustentabilidade à tomada de decisão e diferenciar alternativas de sistema estrutural em concreto por seu desempenho técnico-funcional, ambiental e econômico no ciclo de vida da edificação. Critérios definidos com base na literatura filtraram uma lista preliminar de indicadores técnico-funcionais. ACVs do berço ao portão utilizando o software SimaPro 7.3 embasaram o cálculo de indicadores ambientais. Previsões da vida útil (VUe) e estimativas do custo do ciclo de vida (CCV) foram obtidas com o software Life-365 v.2.1.1. Para garantir 50 anos de vida útil de projeto (VUP) e atender ao requisito de durabilidade da ABNT NBR 15575:2013, a VUe foi corrigida por um programa de reparos. Indicadores técnico-funcionais foram calculados com base nas pranchas de projeto estrutural. Processo de análise hierárquica foi usado para definir sua importância relativa. Para a dimensão ambiental, adaptou-se a ponderação hierárquica do sistema de avaliação de impactos EcoIndicator 99. Uma ponderação igualitária foi usada nas duas dimensões para análise de sensibilidade. Cenários de importância relativa entre as dimensões técnico-funcional, ambiental e econômica foram predefinidos para ilustrar potenciais perspectivas de diferentes partes interessadas. Essa estrutura de indicadores e cenários de ponderação foi aplicada a 31 estudos de caso de tipologia vertical em concreto armado e protendido, em ambiente marinho do sudeste brasileiro. Resultados demonstraram a veracidade da hipótese, confirmando (i) que os indicadores mostram diferenças entre as estruturas, tanto no pavimento-tipo quanto na superestrutura, bem como, entre sistemas em concreto armado e protendido, e para os cenários propostos, as estruturas em laje protendida apresentaram desempenho global superior ao das estruturas em concreto armado, exceto quando se privilegia a dimensão ambiental, em que se observa o melhor desempenho desta última; (ii) não haver diferença entre as tipologias residencial e comercial para a finalidade desse estudo; (iii) a validade de considerar o pavimento-tipo representativo da superestrutura para o cálculo dos indicadores, exceto para os ambientais; (iv) haver uma correlação linear significativa entre os indicadores espessura equivalente e densidade de pilares com o número de pavimentos; e (v) que a unidade funcional ¿ m2área estrutural de uso residencial e comercial e VUP de 50 anos ¿ consegue capturar aspectos de durabilidade e função estrutural, aliada à facilidade em coletar dados nos escritórios de projeto, e realizar análises comparativas entre diferentes estruturas de edificações de mesma tipologia. Palavras-chave: indicador de desempenho; sustentabilidade; sistema estrutural em concreto; ACV; CCV / Abstract: Research initiatives for next generation assessment protocols state that buildings sustainability should always be described and assessed with the help of relevant indicators. Life cycle-based studies show the structural system as one of the major contributors to buildings environmental loads. However, structural systems have not gained enough attention in the sustainability/environmental buildings assessment systems so far. Data on integrated sustainability performance of building parts completely lack in the Brazilian building sector where concrete structures predominate. This study aims at checking the hypothesis that a set of indicators can integrate key aspects of sustainability in design decision-making and differentiate concrete structural system's alternatives by their technical-functional, environmental and economic performances in the building life cycle. Data for computing the technical-functional indicators were extracted from structural design drawings and calculation sheets provided by the responsible structural design practices. SimaPro 7.3 life cycle assessment (LCA) platform supported calculation of environmental indicators. Life cycle costs (LCC) and service life (SL) were estimated by Life-365 v.2.1.1 software. In order to reach the Brazilian standard durability requirement, SL was corrected through adoption of a repair program. Analytic hierarchy process was applied to define relative importance of technical-functional indicators. An adaptation of the life-cycle impact analysis method Eco-indicator 99 was used for weighting environmental indicators. Simulating different stakeholders perspectives, weighting scenarios among the technical-functional, environmental and economic performances were defined to streamline identification of a top performing solution. This framework of performance indicators and weighting scenarios were applied to thirty-one case studies of residential and commercial vertical buildings in reinforced and prestressed concrete in a southeast Brazilian marine environment. Results demonstrated the veracity of the hypothesis, confirming that (i) indicators were successful in showing structural systems¿ differences, both at typical floor and superstructure level, as well as between reinforced and prestressed concrete structures. For the proposed scenarios, the overall performance of prestressed structures exceeded all reinforced concrete structures¿ overall performance, except when it favors the environmental dimension, where the best performance of the latter is observed; (ii) there is no difference between commercial and residential typologies for the purpose of this study; (iii) a typical floor is representative of the whole superstructure for calculating technical-functional and economic performance indicators, but not for environmental indicators; (iv) there is a significant correlation between the indicators equivalent thickness and density of columns with the number of building floors; (v) the functional unit ¿ m2structural area for residential and commercial live loads for 50 years design life (DL) ¿ can capture aspects of durability and structural function, with the ease of collecting data in design offices, and performing comparative analyzes between different building structures of the same type. Additionally, for such analysis, the results show (vi) that more information and standardized presentation of quantitative data are needed in structural design drawings to facilitate data collection for indicators¿ calculation. Keywords: performance indicators; sustainability; concrete structural systems; LCA; LCC / Doutorado / Arquitetura e Construção / Doutora em Engenharia Civil
103

Méthodologies d’analyse environnementale des filières bioénergie : approches par analyse de cycle de vie et nouvelles approches spatiales / Environmental analysis methodologies of biofuels supply chains : life cycle analyses and new spatial approaches

Heredia, Manuel 04 July 2012 (has links)
Cette thèse vise à fournir des bases d’informations et des outils qui font actuellement défaut dans l’analyse environnementale des filières biocarburant, en particulier dans l’analyse de cycle de vie (ACV). Ce travail comprend deux volets complémentaires. Le premier volet s’intéresse aux filières biocarburants à l’échelle internationale. Une étude descriptive permet de définir le système PEC (Production, Elaboration, Consommation) pour représenter ces filières. Dans cette représentation, un outil de reconstitution des filières basé sur les flux d’échanges internationaux en bioproduits est développé. Appliqué aux consommations de biodiesel de l’Union Européenne (UE), cet outil montre que les surfaces agricoles mobilisées au sein l’UE passent de 72% du total en 2004 à 24 % en 2009. Les surfaces agricoles « distantes » (hors UE) sont à la fois mobilisées par importations de bioproduits (22 à 46%) et à travers les importations directes de biodiesel (0 à 40%). Cet outil produit des matrices d’allocations d’impacts basées sur les consommations nationales, utiles pour l’ACV. Le deuxième volet s'intéresse aux zones de production de matières premières en considérant une échelle locale afin d’intégrer leurs hétérogénéités spatiales et leurs spécificités territoriales. Les zones de production sont localisées dans les principaux pays producteurs approvisionnant les filières biocarburants de l’UE. L’examen de ces situations de production permet d’identifier la nature des impacts locaux in situ et d’en analyser la criticité en fonction du contexte national et territorial. Des approches spatialisées à partir de Systèmes d’Information Géographique (SIG) sont appliquées aux filières bioéthanol au Brésil. Ces approches aboutissent à la caractérisation des zones d’emprises dues aux unités de bioéthanol au Brésil, ainsi qu’à la mesure d’indicateurs propres aux différents bassins de production identifiés (stabilité spatiotemporelle de l’expansion de la canne à sucre). La compréhension des structurations et des interactions à l’échelle des filières couplée à la mise en œuvre d’approches spatialisées conduit à mieux prendre en compte les aspects spatiaux prépondérants dans l’analyse environnementale et les études ACV des biocarburants consommés en Europe. / This work aims to provide informations and tools that are currently lacking in the environmental analysis of biofuels, especially in the life cycle analysis (LCA). This work includes two complementary parts. The first part focuses on biofuels supply chains at international scale. A descriptive study allows us to define the PEC system (Production, Elaboration, Consumption) to represent these supply chains. A tool is developed to describe and quantify PEC entities from biofuel consumption to areas of primary crops production. This tool is applied to biodiesel consumption in the EU using bioproducts flows data taken from international trade databases. It shows that biodiesel consumption involves a rapidly growing contribution of crop areas outside the EU (Non-EU), increasing from 28% in 2004 to 76% in 2009. Non-EU crop areas are indeed simultaneously mobilised through imports of bioproducts (22-46%) and through direct imports of biodiesel (0-40%). This tool eventually produces allocation matrices, based on national consumption, which are useful for LCA. The second part focuses on primary crops areas by considering a local level in order to integrate their spatial heterogeneities and territorial specificities. Primary crop areas in major producing countries supplying EU's biofuel consumptions are localised. Examination of the production situation in important countries allows to identify the nature of in situ local impacts and to study criticality of impacts in the national and territorial context. Then, spatial approaches based on Geographic Information Systems (GIS) are applied to bioethanol industries in Brazil. In this approach, about 620 ethanol plants in Brazil are localised using GIS and their supply areas are characterised. This leads to the measurement of specific indicators, such as spatiotemporal patterns of sugarcane expansion. These results are a contribution to the understanding of the structure and interactions among supply chains and to a better consideration of the spatial aspects in environmental analysis and LCA studies of biofuels consumed in Europe.
104

Définition des indicateurs clés de performance et évaluation multicritère de filières durables de recyclage des polymères renforcés de fibres de carbone issus de l’industrie aéronautique / Definition of key sustainability performance indicators and multicriteria evaluation of recycling sector for carbon fiber reinforced polymers from the aerospace industry

Pillain, Baptiste 30 June 2017 (has links)
La consommation globale de plastique renforcé de fibres de carbone (PRFC) est en constante augmentation, ce qui induit la nécessité de créer un secteur de recyclage capable de traiter l’ensemble des fibres de carbone actuellement consommées et qui représente la quantité de déchets à traiter en devenir. Cette thèse porte sur le développement et l'application d’une méthodologie d’évaluation multicritère du développement durable pour la création d’une filière de recyclage des plastiques renforcés de fibres de carbone (PRFC) issus du secteur aéronautique, mais aussi des autres secteurs consommateurs de fibres de carbone tels que l’automobile et l’éolien. Cette méthodologie a pour but d’identifier les indicateurs les plus pertinents ainsi que les méthodes qui leurs sont associés, c'est-à-dire qu’elle vise à la création et l’adaptation d’indicateurs clé de performance du développement durable pour caractériser au mieux les impacts environnementaux et sociaux-économique de cette filière de recyclage. Le résultat final de ce travail est la création d’une méthodologie d’évaluation du développement durable dédiée à la filière de recyclage des fibres de carbone par la considération des différents aspects de celui-ci. Cette méthodologie, aidant à l’identification et la définition des indicateurs clé de performances du développement durable peut être aussi appliquée à d’autres secteurs souhaitant s’implanter en suivant les principes de ce développement. / The global consumption of carbon-fiber reinforced plastic (CFRP) is constantly growing since the last decade, leading to the need to create a recycling sector able to manage the amount of carbon fibers currently consumed and representing the amount of waste to be treated in the future. This thesis focus on the creation of a methodology for evaluating the sustainability potential for the implementation of a carbon fiber reinforced plastics recycling (CFRP) sector. CFRP coming from the aeronautics sector as well as other sectors such as the automobile and wind-energy industries. This methodology aims at identifying the most relevant indicators and associated methods, but also aims at the creation and adaptation of indicators to best assess the environmental and socioeconomic impacts of this recycling sector. The final result of this work, is the creation of a sustainability assessment methodology dedicated to the carbon fiber recycling sector, considering the different sustainability pillars. However this methodology also define more widely a tool that helps to identify sustainability performance indicators and that can be applied to other sectors if necessary.
105

Byggnadsdelars klimatpåverkan i träbyggnadssystem : En jämförelse för optimering / The impact on climatic change from building components in wooden building systems : A comparison for optimisation

Persson, Dennis January 2020 (has links)
Sverige är berikat med en mycket stor areal av skog, vilket ger oss stora möjligheter till att utnyttja trä som ett närproducerat konstruktionsmaterial. Detta betyder att vi har en stor förnybar källa nära till hands som alltid kan vara tillgänglig om vi använder den på rätt sätt, vilket i sin tur skapar fördelar för miljön och ytterligare intresse till att använda trästommar och träbaserade material i alla möjliga sorts byggnader. När det kommer till byggnadsdelar så görs vissa val av material och byggteknik för att klara av krav på exempelvis ljud, brand, värmeledningsförmåga och bärförmåga. Syftet med detta arbete är att visa vilka inriktningsval och materialval man bör fokusera på ur klimatsynpunkt när det kommet till beslut gällande olika konstruktionslösningar i träbyggnadssystem. I arbetet så är målet att klimatpåverkan från olika väggar av konstruktionsvirke respektive korslimmat trä (KL-trä) studeras i detalj och en översiktlig inblick i bjälklags påverkan ges.   Väggarnas utformning är framtagna av författaren med beräkningar i Excel utifrån specifika krav på U-värde, bärförmåga och brand förutom för KL-träväggarna där brandlastfallet kontrollerades med hjälp av programvaran SPFit2.0. Inga beräkningar görs för ljudkrav utan behandlas endast i text. En funktionell enhet är det ramverk med krav som används för samtliga byggnadsdelar för att göra de jämförbara med varandra. Referensprojektet i studien är en förskola med två våningar och den funktionella enheten som använts är baserad på referensprojektet och därav de krav som ställs på den byggnadstypen. Totalt 60 stycken väggar har studerats och består av både ytterväggar och innerväggar. Resultaten bygger på livscykelanalyser och är framtagna via verktyget Byggsektorns Miljöberäkningsverktyg (BM). Två stycken bjälklag har studerats varav båda består av KL-trä. Bjälklagen är tagna från existerande projekt som omfattar en förskola med två våningar och som har trästomme.   Resultatet visar att, för att minska klimatpåverkan, kan och bör brandgips undvikas i de studerade stomsystemen. Beklädnader som man bör rikta in sig på ur klimatperspektivet är vanliga gipsskivor och ensamstående träbaserade skivor där möjligheten finns. Cellulosaisolering eller stenull bör användas istället för glasull. Densiteten hos stenullen kan ha en relativt stor negativ påverkan på resultatet och bör hållas låg ur klimatsynpunkt. En optimering ur klimatsynpunkt av väggar i en byggnad är inte en suboptimering, men relativt sett står bjälklag för en större klimatpåverkan än väggarna. Optimeringen av väggar kan resultera i drygt 7 procents reducering av varje våningsplans klimatpåverkan och kan även uppgå till att vara högre. Även olika uppbyggnader av en byggnadsdel inom samma stomsystem kan ge upphov till stora skillnader i byggnadsdelens klimatpåverkan. / Sweden is a country that is enriched by forest. This provides Sweden with the opportunity of having a lot of locally produced wooden building components. In brief, this means that we have a renewable source that will always be accessible if we utilize it in a correct manner. This grants a lot of benefits for the environment and creates a greater interest of practicing wooden building systems and the use of other wooden based materials in all sorts of buildings. When it comes to building components there are different choices that has to be done in order to overcome certain requirements regarding acoustics, fire safety, thermal conductivity and load bearing capacity. The purpose of this study is to show, based on the climatic impact, which decisions and materials to focus on when constructing buildings in wooden building systems. Here, the climatic impact from walls are thoroughly studied and the impact from slabs are given a general insight. The walls are using either cross-laminated timber (CLT) or studs made from construction timber.   The walls are formed by the author and all calculations regarding thermal conductivity, load bearing capacity and fire safety are made in Excel. The only exception is the load bearing capacity during a fire for walls using CLT where the software SPFit2.0 have been used. No calculations regarding acoustics have been made. A functional unit is the frame that forms the requirements that has to be met by every studied building component in order to make the results comparable between the different building components. The reference project for this study is a two-story preschool and the functional unit is based on that reference building. A total of 60 walls have been studied, consisting of both outer and inner walls. The results are based upon life-cycle analysis and are produced from a software called Byggsektorns Miljöberäkningsverktyg (BM). Only two slabs have been studied whereas both use CLT. The slabs are taken from already existing projects that consists of a two-story preschool using a wooden building system.   The results show that plasterboards designed to withstand fire better are recommended to be avoided in these wooden building systems. Instead, the preferred coverings are regular plasterboards and single wooden based coverings where possible. Cellulose insulation and rockwool are the favored insulation materials rather than glass wool. The density of the rockwool may have a large impact on the result and is recommended to keep low. The optimisation of walls, based on climatic impact, is shown to not be a sub-optimisation, although the majority of the climatic impact comes from slabs. Optimised walls can result in a reduce of 7 percent on every floorplan and may also be higher. Even different variations of walls within the same wooden building system may cause large changes on the climatic impact.
106

Klimatpåverkan av stommaterial på Regnbågens förskola i Årjäng : Med fokus på koldioxidutsläpp vid val av KL-trästomme alternativt stålstomme med utfackningsväggar av trä och bjälklag av betong. / Climate impact of frame materials at Regnbågens Preschool in Årjäng : Focusing on carbon dioxide emissions depending on selection of CLT frame or a steel frame with timberstructure compartment walls and concrete floors.

Klemetz, Jacob, Eklund, Joseph January 2020 (has links)
Idag förbrukas jordens resurser i högre takt än vad jorden klarar av att bearbeta. Byggbranschen tillhör en av de sektorer som har högst klimatpåverkan, främst i form av koldioxidutsläpp. Därför pågår ett kontinuerligt arbete med att ta fram byggnadsmaterial som skall minska belastningen på miljön.  I byggbranschen kan man se en trend att korslimmat trä (KL-trä) blir allt mer efterfrågat som stommaterial. Det sägs ge upphov till mindre miljöpåverkan samt ge ett bättre inneklimat än vad andra stommaterial gör.   Denna studie visar en teoretisk jämförelse av klimatpåverkan samt av inomhusmiljön mellan en KL-trästomme och en kombinerad stål- och betongstomme. Båda stomalternativen har projekterats av ByggDialog tillsammans med deras samarbetspartners. Referensbyggnaden är Regnbågens förskola i Årjängs kommun. Syftet med denna studie är att uppmärksamma, skapa en medvetenhet samt ge verktyg till ByggDialogs kunder för att göra ett klimatsmart stomval, vilket i sin tur också kan bidra till att de svenska hållbarhets målen uppnås till 2030. Klimatpåverkan beräknades under produktskedet vilket innebär råvaruförsörjning, transport och tillverkning för ingående material (modul A1-A3) med hjälp av ett Global Warming Potential-värde (GWP-värde). Vilket är ett värde på hur stor klimatpåverkan ett material ger upphov till i form av utsläpp av koldioxidekvivalenter. För att undersöka hur stomval påverkar inomhusmiljön gjordes en litteraturstudie.   Resultatet visade att KL-trä som stommaterial gav upphov till cirka hälften så stor miljöpåverkan vad gäller koldioxidutsläpp men var cirka 12% dyrare att uppföra jämfört med en kombinerad stål- och betongstomme. Vid beräkning av koldioxidutsläpp per SEK visade det sig att en stomme av KL-trä hade cirka 67% lägre koldioxidutsläpp per SEK än vad en kombinerad stål- och betongstomme hade.  Litteraturstudien visade att KL-trä som stommaterial gav en jämnare luftfuktighet men sämre värmelagringsförmåga och ljudabsorption i form av steg- och stomljud jämfört med en kombinerad stål- och betongstomme. Forskning visade att synligt trä till exempel KL-trä, ger en upplevelse av trygghet, avkoppling och allmänt välbehag för människor som vistas i byggnaden. / Today, the Earth's resources are used at a higher rate than the Earth can manage. The construction industry is one of the sectors that have the greatest negative climate impact, mainly related to high carbon dioxide emissions. This industry continuously strives to develop building- and construction materials resulting in an as low  environmental footprint as possible. Recent trends, in the construction industry, shows an increase in the use of cross-limbed timber (CLT) for frame material. The claim is lower environmental footprint at the same time as it gives a better indoor climate compared to other frame materials.  This study will be a theoretical comparison of the climate impact as well as the indoor environment between a CLT frame and a combined steel and concrete frame. Both frame alternatives have been designed by the construction company ByggDialog together with their partners. The reference building for this study is Regnbågens Preschool in Årjäng Municipality. The purpose of this study is to raise and create awareness and also provide tools for ByggDialog and their customers enabling a climate-smart frame selection. This will most likely also  contribute to achieving the Swedish sustainability goals by 2030. By using data from the Global Warming Potential (GWP) for the input materials, the climate impact was calculated. Each construction frame type data was analyzed during the product phase which include raw material supply, transport and manufacturing (module A1-A3) in the form of emissions of carbon dioxide equivalents. A literature study was also conducted to analyze how a frame of CLT affects indoor environment.  The result showed that by using a CLT frame material versus a combined steel and concrete-frame the environmental reduction was about 50% and about 12% increase in cost. When calculating the carbon dioxide emissions per SEK, it was found that the CLT frame construction had about 67% lower carbon dioxide emissions per SEK compared to a combined steel and concrete frame. The literature study showed that a frame material of CLT provides a more evenly distributed humidity, poorer heat storage capacity and less sound absorption capacity in the form of step- and frame sound compared to a combined steel and concrete frame construction. Further research in this field indicates that by having visible wood, for example a CLT frame provides an experience of safety, relaxation and general well-being for people in the building.
107

The Potential of Reducing Carbon Footprint Through Improved Sorting / Potentialen att minska klimatavtrycket genomen en ökad källsortering

Olsson, Fredrika January 2020 (has links)
Almost five million tonnes of household waste was generated in Sweden in 2018, half of which was residual waste sent for incineration with energy recovery. For materials that can not be recycled or biologically treated, incineration with energy recovery is considered a preferred management option. The issue is that the fraction for residual waste contains considerable amounts of wrongly sorted materials, such as food waste and plastic packaging, which can be recycled or biologically treated, thus causing a smaller environmental impact. To quantify the composition and waste quantities of the wrongly sorted materials a waste composition analysis of the residual waste from four community bins in Västmanland county was conducted. The analysis revealed that about two-thirds of the waste was wrongly sorted and only one-third was actual residual waste. Life cycle analysis was subsequently used to calculate the carbon footprint of the wrongly sorted food waste and plastic packaging waste as well as the carbon footprint from optimal sorting and treatment of the materials. The investigation concluded that for food waste, anaerobic digestion caused a smaller climate impact than incineration with energy recovery and for plastic packaging, recycling generated a smaller climate impact than incineration with energy recovery. The size of the carbon footprint for the different management methods was in line with the priority order given in the waste hierarchy, stated in Swedish legislation.  However, the size of the potential climate savings partly depended on the choices made in the life cycle analysis where the most sensitive parameters were related to external production of heat, polymer resin and vehicle fuel. If the potential climate savings is extrapolated for VafabMiljö's entire collecting area, the total climate savings per year would be 8 263 tonnes of carbon dioxide equivalents per year for food waste and 2 070 tonnes of carbon dioxide equivalents per year for plastic packaging waste. This would be equivalent to driving 1 250 laps around the Earth with a car every year or flying 14 900 times Sweden–Thailand back and forth every year. / Nästan fem miljoner ton hushållsavfall genererades i Sverige under 2018, varav ungefär hälften skickades till energiåtervinning. För avfall som inte kan materialåtervinnas eller behandlas biologiskt anses energiåtervinning vara den bästa metoden för avfallshantering. Problemet är att stora mängder återvinningsbart material såsom matavfall och plastförpackningar felaktigt hamnar i restavfallet när det istället hade kunnat återvinnas och på så sätt medfört en mindre miljöpåverkan. För att kvantifiera samansättning och avfallsmängder av det felaktigt sorterade materialet, gjordes en plockanalys på restavfallet från fyra miljöbodar i Västmanland. Analysen visade att ungefär två tredjedelar av materialet var felaktigt sorterat och endast en tredjedel utgjordes av övrigt restavfall. Livscykelanalys användes därefter för att beräkna klimatavtrycket för det felaktigt sorterade matavfallet och för plastförpackningarna som återfanns i restavfallet såväl som klimatavtrycket för optimal sortering och hantering av materialen. Ordningen i avfallshierarkin visade sig stämma väl överens med klimatavtrycket från de olika behandlingsmetoderna i det undersökta området. För matavfall innebar rötning en lägre klimatpåverkan än energiåtervinning och för plastförpackningar medförde materialåtervinning en lägre klimatpåverkan än energiåtervinning. Storleken på besparingarna av växthusgaser berodde dock till viss del på val av inparametrar och de faktorer som främst påverkade var alternativ produktion av värme, plastråvara och drivmedel. Om resultaten extrapoleras över hela VafabMiljös upphämtningsområde så skulle de totala klimatbesparingarna för matavfall vara 8 263 ton koldioxidekvivalenter per år och för plastförpackningar 2 070 ton koldioxidekvivalenter per år. Dessa besparingar är jämförbara med bilkörning motsvarande 1 250 varv runt jorden varje år eller 14 900 tur- och returresor med flyg Sverige–Thailand varje år.
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Sustainable Public Procurement : Development and analysis of tools for construction works

Verzat, Benoit January 2008 (has links)
Embedded in the economic competition, public procurement has amajor role to play in being a driving force for the promotion of a globallypositive competition that prides the best sustainable products and services,rather than only the more economically efficient ones. Responsible for ahuge part of the human pressure on natural resources, and having a largeshare in the public funding, the built environment sector provides animportant venue for the use of sustainable public procurement as a tool toenhance the sustainability of societies.Selecting the best sustainable offer is a challenging task requiringenvironmental and social assessments that can only be based on complexlife cycle thinking analysis. Through the development of the “ExhaustiveSustainable public procurement clauses Manual”, this paper analyses publicprocurement issues and their potential solutions, with a focus on theenvironmental performance in buildings procurement.
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Environmental Systems Analysis of Waste Management : Prospects of Hydrogen Production from Waste for use in FCVs

Assefa, Getachew January 2000 (has links)
ORWARE, an evolving systems analysis based computer model is used to assess the performance of different waste management options from a life cycle perspective. The present version of the model consists of different submodels for transport, treatment, and disposal of different types of liquid and solid wastes and recycling of materials. Flows between submodels are described by a vector of several substances of different relevance to the system. The model calculates emissions to water and air, amount of residues returned to arable land and energy flows using the tools of life cycle analysis (LCA) and substance flow analysis (SFA). In going in the direction of stringent environmental standards and policies, there is a need for maximizing energy recovery from waste for both environmental and economic benefits. Sweden has already experience of recovering energy from waste for district heating. Recovering energy not only of high value but also of higher quality from waste would be of interest. Hydrogen is one carrier of such energy. The possibility of using hydrogen from waste as a fuel in the transport sector would contribute in heading for creating a clean environment. In this thesis a new submodel for steam reforming of biogas recovered from an anaerobic digester is developed and used with other submodels within the ORWARE framework. Four scenarios representing alternative ways of energy recovery from the organic waste in Stockholm have been simulated to compare the associated energy turnover and different environmental impacts. Digestion of the organic waste and using the biogas to fuel cars is compared against steam reforming of biogas to hydrogen or thermal gasification of the waste and processing the product gases to hydrogen. In the latter two cases hydrogen produced is used in fuel cell cars. Avoided impacts of using the biogas and hydrogen are analyzed using the fourth scenario where the waste is incinerated to generate heat and electricity. Functional equivalence between scenarios is achieved by external supply of heat, electricity and petrol. While recognizing the uncertainties during modelling and simulation, it is possible to conclude that the results indicate that there is advantage of reduced environmental impact and high energy turnover in introducing the technologies of producing hydrogen from waste into the waste management system. Further and thorough investigation is recommended to come up with a sound and firm conclusion. Key words: Systems analysis, Life cycle analysis, Substance flow analysis, Waste management, Environmental impact, Steam reforming, Thermal gasification, Fuel cell vehicles, Hydrogen <img src="http://www.webforum.com/form/kthima/images/spacer.gif" /> / www.ima.kth.se
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EKODESIGN I INDUSTRIN : En lägesanalys av producenters problem, drivkrafter och framtida utmaningar inom ekodesign / ECO DESIGN IN PRODUCT INDUSTRY : An analysis, based on producers problems, driving forces and future challenges in eco design

Bergsten, Karolina, Langborg, Ida January 2012 (has links)
SammanfattningProdukter produceras idag i stor utsträckning för att tillfredsställa konsumenters behov varpåmiljöbelastningen eskalerar i takt med efterfrågan och produktionen som sker därefter. Lösningenpå problemet kan sammanfattas i ekodesign där miljöoptimering av produktutvecklingen skerutifrån ett helhetsperspektiv; råvaruutvinning, produktion, användning, återvinning, slutligtomhändertagande samt transporter.Teknik-konsultföretaget ÅF uppmärksammade detta problem hos svenska producenter ochstartade 2008 en intern sektion, EcoDesign center, som erbjöd sina kunder ekodesignrelateradetjänster. Utmaningarna och problemen hos kunderna har med tiden förändrats och för att centretska kunna erbjuda sina kunder relevanta tjänster, undersöks i detta arbete svenska producentersrelation till ekodesign idag.Syftet med arbetet har varit att kartlägga producenternas problem och utmaningar inommiljöanpassad produktutveckling och samtidigt utvärdera ÅF EcoDesign centers förutsättningaratt tillgodose sina kunder. Att utifrån denna kunskap komma med förbättringsförslag ochrekommendationer på hur centrets ekodesigntjänster kan optimeras har varit målet med arbetet.Resultatet visar att ekodesignarbetet inte är tillräckligt utbrett vilket främst beror på bristfälligefterfrågan av ekodesignade produkter. Kundefterfrågan är direkt kopplat till ekonomiskaincitament, företag drivs i vinstsyfte och utan en efterfrågan kommer ekodesignarbete inteimplementeras. Producenterna har inte insett eller förstått den ekonomiska potentialen medmiljöeffektiv produktutveckling och tror det är dyrt och tidsödande. En orsak till detta kan varabristen på enkla ekodesignverktyg, då de flesta existerande verktyg kräver experter.Kunskapsbristen är ett faktum, vilket producenterna själva ser som ett av de största hindren förimplementering av ekodesign i produktutvecklingsprocessen.ÅF:s EcoDesign center bör satsa på en inledande ekodesigntjänst som kartlägger vad för typ avekodesigntjänst deras kunder behöver hjälp med. Denna tjänst ska fungera som en inkörsport tillövriga ekodesignområden som EcoDesign center rekommenderas att satsa på i framtiden; PRS(Product Regulatory Support), strategi, eco screening, utbildning, tjänstedesign ochmarknadsföring. / Products are currently produced to satisfy customer needs to a large extent whereupon theenvironmental impact escalates due to the demand and production. A solution to the problemcan be summarized in the term eco design where the environmental optimization of a producthas a holistic perspective, including everything from raw material extraction, production, uses,recycling, disposal and transport.ÅF, a technology consulting firm, drew attention to this problem and started EcoDesign centerin 2008, an in-house section where they offered their customers eco design related services. Thechallenges and problems in their customers needs have changed over time and understandinghow the center should provide their customers with relevant service is investigated in this thesis.The aim of the thesis has been to identify producers’ problems and challenges with greenproduction and at the same time evaluate EcoDesign center's prerequisites to satisfy theircustomers’ needs. Based on this knowledge, the aim has been to come up with suggestions andrecommendations on how the center can optimize their eco design related services.The result shows that the eco design work is not sufficiently widespread, mainly due to a poordemand for eco designed products. Customer demand is directly linked to economic incentives,companies run for profit and without a demand an eco design work will not be implemented.Producers have not realized the economic potential of eco effective products and think it isexpensive and time consuming. One reason can be the lack of simple eco design tools, sinceexisting tools require expertise. The lack of knowledge is a fact, which the producers consider tobe one of the biggest obstacles to implement eco design in the product developing process.EcoDesign center should invest in an initial eco design service that identifies in which types ofeco design areas their customer needs help. This service will act as a gateway to other eco designservices offered at the center. In the future, EcoDesign center is recommended to focus on thefollowing, eco design related work; PRS (Product Regulatory Support), strategy, eco screening,education, service design and marketing.

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