<p>To accurately estimate the potential recovery of metals from electronic devices, various tools such as mass flow analysis, dynamic models, and forecasting models have been employed. However, the reliability of the model-generated outputs hinges on the accuracy of the input data. To ensure accurate data collection, it is imperative to examine and compare different methodologies. Although surveys have conventionally been used in information and telecommunications technologies to gather consumer information, their validity is seldom contrasted with alternative methods due to the lack thereof. In response, a new mixed methodology has been developed to obtain primary consumer data through tangible information, offering new avenues for data acquisition. The methodology involves quantitative and qualitative approaches taking direct physical measurements (dimensions, weight, and quantity) of devices and including a ten question semi-structured interview to discussed consumer devices use, stock and transfer patterns, composition changes of the electronic devices, and disposal behavior. As a result, it was found new methodology measured 79% of the devices directly at laboratories and 21% of the remaining devices were self-reported by the participant. The devices on consumer stage frequently have the same type and number of components as fabric and a positive difference of about 17.99 g compared with the mass reported by fabricants or literature. The sequential steps undertaken by participants in the new methodology to acquire consumer-stage data offer distinct advantages over surveys, particularly in capturing a more comprehensive inventory of devices in storage.</p><p>Additional results indicate that the proposed methodology can provide valuable insights into the stock of electronic devices. Nevertheless, further research is required to understand the implications of surveys versus direct measurements in accurately representing mass flows during the user stage. Additionally, the relevance of external power supply or charging systems on storage will be explored as part of the supplementary findings. By improving the accuracy of metal recovery estimation and exploring more effective data collection methods, we can optimize closed-loop projects and contribute to sustainable resource management.</p>

In the production of glass, the addition of more cullet to the batch of glass and the reduction of the thickness of glass are means to reduce energy consumption and raw material usage. This contributes towards improved energy efficiency targets of the European Union. This thesis investigated the energy consumed for the process of strengthening thinner glass as well the environmental implications of thinner and stronger compared to conventional glass across the life cycle of glass. The life cycle phases also included a recycling phase where 70% of the used glass was recycled with the remaining 30% being landfilled. The functional unit selected for this study was 1m2 of SLS glass, 4mm thick, with an average light transmittance of 91%. This corresponds to 10kg of clear float glass as per general rule. The findings of this thesis showed that one of the major contributing factors to high energy consumption in the melting phase of SLS glass is low efficiency of the furnace; this led to significant energy losses in the production of SLS glass. Recycling of flat glass, at a 70% rate, led to a 12% reduction in total global warming potential, a 10% reduction in the Acidification Potential, a 13% reduction in the Eutrophication Potential in marine environs, and a 7% reduction in the Eutrophication Potential in terrestrial habitats. The chemical and thermal strengthening process consumed 2.24 and 2.37 kWh/m2 respectively. The consequential impact of this is dependent on the source of the electricity for the strengthening processes. It was concluded that the energy used for the strengthening of the thinner glass is considerably less than the energy used in the production of a conventional glass that satisfies the same strength parameters.

No description available.

<p>In the Central Hardwood Region, the quantity and quality of hardwood timber critically depend on forest management decisions made by private landowners, since they hold the largest share of woodlands, some of which are plantations. These plantations are in a unique and critical position to provide much-needed hardwood resources. However, there is a lack of research and tools enabling rigorous assessments of profitability of long-term investments in hardwood plantations. Partially due to this, the majority of these privately held plantations remain unmanaged.</p> <p>This study aims at providing scientific evidence and tools to help promote forest management on hardwood plantations held by private landowners. To this end, I demonstrate in Chapter 1 an economic-modeling approach that minimizes establishment costs while ensuring free-to-grow status by year 5, and crown closure by year 10. Using temperate hardwoods such as black walnut and red oak as focal species, I find a black walnut plantation can attain crown closure in year six at the lowest cost ($4,540/ha) with 6 feet x 7 feet spacing, herbicide application for the first year, and fencing. For red oak, the minimum-cost option ($5,371/ ha) which achieves crown closure in year 10 requires a planting density of 6 feet x 7 feet, herbicide application for the first three years, and fencing. Modelling uncertainty in growth and mortality in a stochastic counterpart shifts optimal solutions to denser plantings for black walnut; planting more trees is, thus, risk mitigative. Based upon these research outcomes, I identify the tradeoffs between efficacy of treatments towards establishment success viz a viz their relative costs which serve as a solid foundation for the assessment of subsequent management strategies.</p> <p>Next, in chapter 2, I first calibrate growth, yield, and crown-width models for black walnut trees with existing and new tree measurements on selected Hardwood Tree Improvement and Regeneration Center (HTIRC) plots. Using spatial information on trees, I develop an individual tree level thinning model and simulate their post-thinning growth and yield. Significant predictors of annual diameter growth between years 10 to 18 include the initial tree DBH, forest edge effects, distance-dependent neighborhood competition, and tree age. Significant edge effects exist up to 3 rows and 3 trees from the non-forested edge. A tree on the perimeter rows grows 0.30 cm (0.12in.) in DBH more per year than the interior trees, between years 10 to 18. Next, I dovetail my results from the spatially explicit thinning model with the USFS Forest Vegetation Simulator (FVS) to understand the impacts of different scenarios of planting densities, site productivities, thinning treatments, and expected yields (as percentage of the total volume) of veneer sawlogs to quantify the growth and profitability from the mid-rotation until the final harvest. To support the attendant financial analyses, I incorporate risk into these projections by simulating stochastic windthrows based on certain assumptions. My projections suggest that, without the threat of windthrow damage, the net present day value (NPV) could exceed $4,900 per acre on the highest quality sites (SI =100) and high densities at planting (6 feet x 6 feet), assuming 10% or more of final volume was veneer and using a 3% discount rate. In contrast, under simulations of probable windthrow disturbances from mid-rotation to final harvest, the chances that standing timber value at harvest exceeds $5,000 per acre are 43.13% for a 96- and 90-year rotation and increase to 45.48% for 75 and further to 56.04% for 60.</p>

Syftet med detta examensarbete var att utveckla ett hållbart ersättningsmaterial till akrylnitrilbutadienstyren plast (ABS), genom att applicera principerna för grön kemi och teknik. ABS är en icke-nedbrytbar plast som till exempel används i slagtåliga produkter för hyttinteriörer. Att utveckla ett nytt material baserat på en kravspecifikation med en specifik produkt i åtanke är av stor betydelse då en initial teoretiska utvärdering kan ge resultat som driver ytterligare innovation och säkerställer en god överensstämmelse med förväntningarna på produkten. Baserat på den genomförda litteraturutvärderingen och kravspecifikationen för produkten valdes polylaktid (PLA) som matrismaterial och blandades med nanofibrer av lignocellulosa (LCNF) och naturgummi (NR), där maleinsyraanhydrid (MA) användes som kompatibilisator. Denna modifieringsstrategi syftade till att förbättra PLAs styrka och minska dess sprödhet. Flera olika parametrar undersöktes, vilka inkluderar olika torkningsmetoder för LCNF:en och olika metoder för MA tillsats före bearbetningen av blandningen. Termisk analys av blandningarna visade att tillsatsen av LCHF och NR inte påverkar nedbrytningstemperaturen för PLA-matrisen i någon större utsträckning, men att kristalliniteten påverkades av dem och de olika behandlingsmetoderna. Styvheten hos de PLA-baserade materialen var likvärdig ABS, medan elasticitet var generellt likvärdig PLA och där tillsatsen av naturgummi förbättrade materialens deformationskapacitet. SEM bilder indikerade att de tre komponenterna var kompatibiliserade, då fibrösa strukturer och sammanflätade nätverk av LCNF och NR i PLA-matrisen kunde observeras. SEM bilderna visade också att NR agglomererade då stora agglomerat och porösa strukturer uppstod, vilket understryker vikten av att optimera framtida blandningsstrategier. En livscykelbedömning (LCA), enligt en vagga-till-graven metod, förväntas visa lägre koldioxidutsläpp för det föreslagna alternativet jämfört med ABS tack vare tillämpningen av principerna för grön kemi vid produktutformningen. Detta bekräftar den ursprungliga hypotesen om en ökad miljövänligheten hos PLA-baserade ersättningsmaterial jämfört med ABS. / This thesis aims to develop sustainable replacement for Acrylonitrile Butadiene Styrene (ABS) in high-impact applications within construction equipment’s Cab interior. Adhering to the principles of Green Chemistry and Engineering, the study focused on developing and accessing an environmentally friendly substitute for ABS, a commonly used non-biodegradable plastic. Investigating novel materials with a tailored requirements list is vital in materials science and engineering. Theoretical approaches can yield results which drive further innovation, ensuring comprehensive alignment with application expectations through a holistic approach to address critical factors. Following this guideline, the chosen alternative was Polylactide (PLA), fortified with a blend of lignocellulose nanofibers (LCNFs) and natural rubber (NR) at a 10 wt.% concentration, with the addition of Maleic Anhydride (MA) as a compatibilizer. This modification strategy aimed to enhance PLA's strength and reduce its brittleness. The investigation encompassed various parameters, including different LCNF drying methods and variations in additive treatment before melt-mixing with PLA. The outcomes from thermal analysis indicated that the inclusion of reinforcements does not significantly affect the degradation temperature of the PLA matrix. Crystallinity, on the other hand, was found to be influenced by the presence of lignocellulose reinforcements and natural rubber, with intriguing nuances emerging from the interplay of these components and different treatment methods. PLA-based alternatives performed similarly to low grade ABS and had similar stiffness levels. In terms of elasticity, most materials behaved similarly to neat PLA, but the addition of natural rubber enhanced their deformation capacity. Successful compatibilization between lignocellulose reinforcements, natural rubber, and PLA was assumed from the observed fibrous structures and interwoven networks within the PLA matrix. Additionally, the presence of aggregates and porous structures highlighted the challenges posed by rubber agglomeration. Finally, the observation of larger agglomerates beyond typical interphase sizes raised concerns about brittle behavior, emphasizing the need for optimizing blend toughening strategies. The input for a Life Cycle Assessment (LCA), following a cradle-to-gate approach, is anticipated to show lower carbon emissions for the proposed alternative in comparison to ABS due to the principles of Green Engineering applied in the product design, denoting the environmental viability of the PLA-based substitute.

Introduction – The building industry is evolving, this urges for innovative methodologies to facilitate the construction processes including the information exchanges between these to accomplish a sustainable future. In addition, new requirements are being set by the Swedish government and other national authorities with the objective of reducing the climate impact caused by the construction industry, which is responsible for a large amount of carbon dioxide emissions. A helpful tool to estimate the total carbon dioxide emission value is the Life Cycle Analysis (LCA) which depends on the Information Exchanges (IE) and the Level of Development (LOD) in BIM (Building Information Modelling) based projects to achieve a reliable result. Therefore, this research aims to find a better understanding of the relation between LOD, IE and LCA in BIM-based projects. Method – This research is based on an authentic ongoing construction project (casestudy), an assembled theoretical framework based on knowledge of the different subjects: LOD, BIM, LCA and IEs. And how previous researchers have faced similar issues. Also, on various thorough document analysis (BIM model and EIs) obtained from the case study. The mentioned above forms a support basis for this paper. Results – Two different BIM models were used to perform two LCA-simulations. One formed with LOD 200 provided a generic presentation of the studied element, which in this case was the model’s exterior walls. While the other model with LOD 300 generated a complex presentation of the model’s exterior walls. The simulation generated a comparative data showing that the Low LOD model had a climate impact value of 248 000 kg CO2. On the other hand, the High LOD model generated a climate impact value of 137 850 kg CO2, resulting in a 45% difference. The results presents that a lower carbon dioxide emission was caused when utilizing a higher LOD which contains more complex and specific information. The results argue for that a BIM model with the adequate amount of LOD is crucial for obtaining more reliable results when performing an LCA. Analysis – The results obtained from the LCA-simulations enhance the theories about the importance of LOD when performing an LCA. Higher LOD in a model generates more reliable results. Moreover, using a BIM software and an LCA plugin as tools facilitate the various IEs in a project. Discussion – The approach was limited to explore the environmental impact of one construction element, exterior walls, and its different LOD. Also, only the stage A1-A3 was analysed. However, trustworthy results were obtained due to the use of reliable data and research methods.

The global electricity generation industry is very reliant on the use of fossil fuels, particularly natural gas and coal. However, it is quickly becoming a reality that the over-consumption of these resources will continue to lead to significant global damage via global warming, ecosystem destruction, and the depletion of these so-called non-renewable re-sources. To combat this issue, renewable sources such as wind, biofuels and solar are be-coming much more prevalent in the power generation industry, but significant economic, reliability and availability barriers to entry will prevent these sources from being major contributors to the power industry for decades. To this end, this thesis focuses on the design, operation, optimization and life cycle analysis of an integrated solid-oxide fuel (SOFC) cell power plant integrated with com-pressed air energy storage (CAES). This plant, fueled by either natural gas or coal, can make much more efficient use of their limited non-renewable fuel sources, and are capable of achieving nearly 100% carbon capture at the plant boundary. This plant is intended to serve as a more efficient and environmentally responsible alternative to current power generation methods while still exploiting remaining fossil fuels to their fullest extent. This thesis details the design, sizing and simulation of integrated SOFC/CAES plants in Aspen Plus so that full feasibility and techno-economic analyses may be performed, the results of which are then compared to the current state-of-the-art (SOTA) options. In order to compare the plants on an environmental level, full cradle-to-grave life-cycle analyses using the ReCiPe 2008 method are completed for each SOFC-based plant and all comparable SOTA options under a wide range of assumptions and plant configurations, such as the use of carbon capture strategies. Furthermore, detailed reduced-order dynamic models of the integrated SOFC/CAES plants are developed and simulated with a newly developed rolling-horizon optimization method to assess the load-following capabilities of the integrated plant. Real scaled demand data for the market of Ontario, Canada for the years 2013 and 2014 are used as the demand data for the simulations. This thesis takes strides in proving the feasibility of an integrated SOFC/CAES power plant for providing clean, efficient, reliable and cost-effective power using fossil fuels. The next steps for this project involve the development of a lab-scale pilot plant, which would be used to validate simulation results and provide an opportunity for the real-time application and assessment of the potential of this plant design. / Thesis / Doctor of Philosophy (PhD)

Es erfolgt ein ganzheitlicher Vergleich der Systeme Luftwärmepumpe und Sole-Wasser-Wärmepumpe für ein Bestandsgebäude. Für die Bewertung der Umweltfreundlichkeit bzw. Klimaschutzwirksamkeit werden die CO2-äquivalenten Treibhausgasemissionen (THG-Emissionen) und der nicht-erneuerbare Primärenergiebedarf (KEV) der Systeme bilanziert. Für den fairen Vergleich werden Systeme mit investkostengleichen Gesamtinvestitionen gebildet, indem die Luftwärmepumpe zusätzlich um eine PV-Anlage ergänzt wird.

För att nå Sveriges uppsatta klimatmål med netto noll växthusgasutsläpp år 2045 måste bygg- och fastighetssektorn som står för omkring 21% av Sveriges totala växthusgasutsläpp, arbeta för en hållbar utveckling. För att reglera utsläppen av växthusgaser i bygg- och fastighetssektorn har riksdagen infört ett krav på upprättande av klimatdeklaration vid uppförande av nya byggnader från och med januari 2022. Klimatdeklarationen ska redovisa vilken påverkan på klimatet en ny byggnad har genom en livscykelanalys. Kravet på inlämnandet av deklarationen är i slutet av ett byggprojekt. Många aktörer inom byggbranschen menar på att klimatberäkningar behöver påbörjas under tidigare skeden för att kunna påverka byggnadens hållbarhet. Detta då möjligheterna att påverka en byggnads energibehov och dess utsläpp av växthusgaser är som störst i tidigt projekteringsskede. Dock är informationen om den planerade byggnaden begränsad i tidigt skede och projektspecifik information saknas för att djupgående kunna bedöma byggnadens resultat och prestanda. Denna studie fokuserar på implementering av klimatberäkningar i tidiga skeden av projekteringsprocessen, anpassat för arkitekter och konstruktörers dagliga arbete. Detta då metodiska förenklingar och standardiserade tillvägagångssätt rörande klimatberäkningar i tidiga skeden ansetts relativt outforskat i tidigare publiceringar inom ämnet. Syftet med studien är att undersöka hur genomförandet av klimatberäkningar i tidigt skede av projekteringsprocessen kan gå till. Detta för att få en förståelse över hur implementeringen av arbetet med klimatberäkningar kan leda till ökad hållbarhet och ekonomisk lönsamhet i byggprojekt. Med en ökad förståelsen för klimatberäkningsarbetet i tidigt skede, är även målet att ta fram ett förslag på en standardiserad metod som vägleder arkitekter och konstruktörer att ta hållbara beslut i tidiga skeden.  Forskningsmetoden som använts är av kvalitativ karaktär och innefattar en litteraturstudie, fallstudie, intervju- och enkätstudie. Studien har utgått från ett konsultföretag med fokus på områdena arkitektur och byggkonstruktion. Enkätstudien har haft som syfte att undersöka hur arbetet inom fallföretaget fungerar idag. Intervjustudien har fokuserat på hur arbetet kan fungera i framtiden och fallstudien har undersökt/observerat hur arbetet med klimatberäkningar kan utföras i praktiken med hjälp av programvaran One Click LCA. Litteraturstudien har bidragit till djupare förståelser inom ämnet och väglett problemformuleringen i studien. Användandet av flera forskningsmetoder kallas för triangulering och bidrar till stärkt tillförlitlighet och trovärdighet för studien.     Studien visar på att det inledningsvis i ett projekt är lämpligast att använda sig av tidigare gjorda klimatberäkningar för att spara in tid och pengar. Användandet av tidigare beräkningar bör utgå från referensprojekt som organisationen själv tagit fram för att kunna motivera hur beräkningarna gått till. När egna klimatberäkningar utförs är det viktigt att de som utför arbetet med klimatberäkningarna själva är involverade i projektet. Det är även viktigt att alla projektmedlemmar har övergripande inblick i vad som krävs i ett modelleringsverktyg för att indata ska fungera på bästa sätt i ett automatiserat klimatberäkningsverktyg. Genom implementerandet av en standardiserad metod, uppstår en struktur som medför att inga viktiga moment glöms bort samt medför att fler kan få en inblick i arbetet och introduceras till projektet på ett enkelt sätt. Ett förslag på en standardiserad metod är framtaget utifrån analys av empirin i detta arbete och innefattar viktiga punkter för uppstarten/implementeringen av arbetet med klimatberäkningar i en organisation. Det innefattar även förslag på viktiga punkter när det gäller utförandet av klimatberäkningar i specifika projekt. / To reach Sweden’s climate goal of net zero greenhouse gas emissions in 2045, the construction and property sector must act for a sustainable development. Today the sector accounts for around 21% of Sweden’s total greenhouse gas emissions. In order to regulate the emissions of greenhouse gases in the construction and property sector, the government in January 2022 introduced a requirement for establishing climate declaration for the construction of new buildings. The climate declaration must report the impact a new building has on the climate, through a life cycle analysis. The requirement for when the declaration must be submitted is at the end of a construction project. Many actors in the construction industry believes that climate calculations need to be started in earlier stages to be able to affect the sustainability of the building. At the same time the information about the planned building is limited in the early stages and project-specific information is missing to be able to assess the building's results and performance in depth. This study focuses on the implementation of climate calculations in the early stages of the design process, adapted to the daily work of architects and constructors. This as methodological simplifications and standardized approaches regarding climate calculations in the early stages were considered relatively unexplored in previous publications in the subject. The purpose of the study is to investigate how the implementation of climate calculations in the early stages of the design process can be done. This is to gain an understanding of how the implementation of the work with climate calculations can lead to increased sustainability and economic profitability in construction projects. With an increased understanding of the climate calculation work at an early stage, the goal is also to develop a proposal for a standardized method that guides architects and constructors to make sustainable decisions in the early stages.  The study uses a qualitative research method that includes a literature study, case study, interview- and survey study. The study is based on a consulting company with a focus on the areas of architecture and building construction. The purpose of the survey study was to examine how the work within the case company operates today. The interview study has focused on how the climate calculation work can be operated in the future and the case study has examined/observed how the work with climate calculations can be carried out in practice using the One Click LCA software. The literature study has contributed to deeper understandings within the subject and guided the research topic in the study. The use of several research methods is called triangulation and contributes to strengthened reliability and validity of the study. The study shows that initially in a project it is appropriate to use previously made climate calculations to save time and money. The use of previous calculations should be based on reference projects that the organization itself has developed to be able to justify how the calculations were made. When conducting climate calculations, it is important that those who carry out the calculations are involved in the project. It is also important that all project members have an overall insight into what is required in a modeling tool, so the input data operates in the best way in an automated climate calculation tool. Through the implementation of a standardized method, a structure emerges, no important aspects are forgotten, and more people can gain an insight into the work and easily be introduced to the project. A proposal of a standardized method is developed based on the empirical analysis in this study and includes important points for the start-up/implementation of the work with climate calculations in an organization. It also includes suggestions on important points regarding the execution of climate calculations in specific projects.

No description available.