Primary aluminum production brings about severe environmental burden due to its energy intensive process.  Secondary aluminum production contributes to cutting off high energy demand around 90-95% and greenhouse gas emission by remelting scraps. However, previous research indicates melting furnace’s energy efficiency in secondary plant is still very low, which is around 26-29% and more than 70% heat is lost in different way. The objective of this project is to investigate energy consumption and greenhouse gas (GHG) emission in secondary aluminum cast house through process analysis. The result offers a comprehensive overview to aid decision-maker to compare energy consumption and environmental impacts caused by different product or process. This project has been done in collaboration with SAPA Heat Transfer. This project consists of two tasks. First task is aimed to give an overview of annual energy distribution and carbon footprint of per ton aluminum slab in SAPA cast house. In order to analyze energy distribution, mass and energy conservation has been applied for calculation. Meanwhile, International standard method, life cycle assessment, has been used to evaluate greenhouse gas contribution of the whole production process. The second task intends to investigate two effects (melting furnace type, raw material type) on products’ energy consumption and carbon footprint.  Melting furnace’s effect is compared by selecting electric induction furnace and oxy-fuel furnace. On the other hand, raw material’s effect is studied by comparison of four different cast house products which have different raw material recipe. Calculation and analysis results indicates that per ton Sapa cast house aluminum slab consumes energy 3826MJ and contributes to 306kgCO2eq. green house gas. Meanwhile, comparison results show that oxy-fuel melting furnace has higher energy efficiency than electric induction furnace, however, it contributes much more GHG due to consumption of propane fuel. In addition, primary ingot has been concluded as distinct carbon footprint contribution than others contributors (i.e. fuel) for Sapa cast house’s slab.

To meet the national and international climate goals every potential GHG mitigating effort needs to be addressed. The aim of this thesis is to investigate if the wastewater treatment plant (WWTP), Ekebyhov, can reduce its GHG emissions by making changes inthe treatmentprocess. The main GHGs emitted from WWT areN2O, CH4and CO2. To begin with, Ekebyhov’scurrent carbon footprintwas calculated in a base line scenario, using a calculation tool (ECT). The results showed that the total footprintamounted to 522 tons CO2eqper year, with the majority of the emissions (83 %) from the activated sludge process. Five GHG-mitigating measures were identified and potential GHG emission reduction (PGER) was calculated from 1) optimized WWT, 2) urea treated sludge, 3) change of chemicals, 4) green transports and 5) added anaerobic digestion (AD) process. The largest PGER came from added AD, followed by optimized WWT. Finally, the PGER for all measures was calculated and resulted in net negative emissions of -95 tons CO2eq per year. The thesis shows that it is possible to reduce the carbon footprint of Ekebyhov WWTP, even to a net negative result. It is, however important to address other impact categories in a full LCA to be able to make fully informed decisions.

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To reach the Paris Agreement targets, the remaining carbon budget is about 2.3 tons of CO2e per person per year. However, current per capita emissions exceed the target, with a global average carbon footprint of 4.81 tons. PCAs provide a cap-and-trade system to limit emissions of private individuals. The thesis explores the compatibility of PCAs with existing legal regulations, the legal challenges of implementing and governing PCAs, and the potential human rights and equity implications of such schemes from a de lege lata and a de lege ferenda perspective. The findings highlight various regulatory and design deficiencies in current PCA proposals and emphasize the need to address data protection, privacy concerns, and the protection of individual rights. Additionally, the governance dimension of PCAs, including participation rights, transparency, and enforcement mechanisms, needs further development. The thesis concludes that while PCAs can be effective in achieving climate goals, careful consideration of legal requirements and individual rights is essential for their successful implementation. It emphasizes the necessity of comprehensive designs that go beyond technical and economic aspects and take into account legal requirements, individual rights, and equitable distribution.

Wood is often perceived as a flawed material. When painted, technologically treated or sealed, in a pursuit to make it more predictable and durable, some of its most important qualities are mislaid. This project explores the aesthetic, material and constructional possibilities of wood, and suggests the possibility of a wood brutalism architecture. The project includes a written manifesto for the benefits of wood in the human habitat, proposes a CO₂ based economic strategy for our built environment and promotes massive wood buildings as our carbon savings account. To find out what a wood brutalism of today might be, the project includes an analysis of the relationship between the material concrete, Betón-brut and the zeitgeist of the 60´s and 70´s. In the application of the manifesto and Bois-brut on a case study housing project in Östberga, Stockholm, the Trellick tower has acted as a brutalist mirror reference. Vernacular timber buildings have provided clues in the search for the essence of wood.

The worldwide consumption of meat continues to increase and in Sweden the annual consumption has gone from 24 kg/person in 1990 to about 78 kg/person in 2005. This contributes to large environmental impacts such as an increase of greenhouse gas emissions, unsustainable land and resource use and shortage of water. A solution to the problem is to change our diets to be more sustainable. The purpose with this research is therefore to study the positive environmental and health aspects of alternative protein rich products based on soya, grown meat, algae and insects in comparison with meat. The goal is then to compare the environmental impacts from these products by studying different LCA-studies. Furthermore, also to understand how the future will be developed by interviewing producers of meat substitutes in Sweden. Some difficulties of comparing different LCA-studies are the choice of system boundaries, functional units and environmental aspects in the studies. Nevertheless, after studying a large amount of reports and articles about the products conclusions could yet be drawn. The carbonfootprint from beef is up to 20 times larger than from the substitutes and the land use is up to 125 times larger for beef compared to substitutes. Pork and chicken have lower impact but the lowest impact seems to come from producing substitutes based on soya beans. Insects and algae also have a low impact, but the products are still in the stage of development in Sweden due to laws, regulations and lack of knowledge. Regarding the health aspects substitutes could possibly replace meat since both insects and soya are rich of protein. Insects are also rich oniron and other nutrition. Algae consist as well of good nutrition. The companies interviewed in this study were Kung Markatta, Ekko gourmet and Veggi. They had some different opinions on future products, but they could all agree on that we need to eat less meat and more substitutes. The conclusions of this research are that the environmental aspects considered in the analysed LCA-studies are mostly carbon footprint and land use. They show that beef have a larger environmental impact than meat substitutes. It is however recommended to do new studies on products with the same system boundaries and functional units to get a more accurate and comparable result.

Stålindustrin är kraftigt energi och utsläppsintensiv och står för upp till cirka 7% av de globala 𝐶𝑂2-utsläppen. Den huvudsakliga utsläppskällan utgörs av masugnsprocessen där järnmalm reduceras till råjärn med hjälp av fossilt kol i den malmbaserade processvägen. Flera tidigare studier har visat att den mest effektiva metoden för att minska industrins utsläpp av 𝐶𝑂2 och därmed bidrag till klimatförändringar är att öka andelen skrot i kolfärskningsprocessen för att på så sätt minska behovet av råjärn.  Syftet med studien var att undersöka möjligheterna att minska stålindustrins utsläpp av 𝐶𝑂2 genom en ökad andel skrot i kolfärskningsprocessen. Rapporten delades upp i två delar, inledningsvis en litteraturstudie som ge en bild över vilka metoder som finns tillgängliga samt vilken potentiell effekt dessa har. Den andra delen baserades på analyser av produktionsdata från SSAB Oxelösund. Tillsammans med resultatet från litteraturstudien användes analyserna för att ta reda på hur mycket råstålets 𝐶𝑂2-avtryck skulle kunna minskas med användning av metoder relevanta för det specifika stålverkets förutsättningar, förbättringsområden och framtida planer.  Parametrarna som undersöktes utgjordes av effekt på skrotinsmältning samt övriga utmaningar och fördelar kopplat till industrins klimatpåverkan. Resultatet från litteraturstudien visade att det fanns ett flertal effektiva metoder för att öka skrotinsmältningskapaciteten i kolfärskningsprocessen och att dessa vid kombinerad användning har en addidativ effekt och har potential att höja skrotinsmältningen avsevärt. Effekten av dessa är dock till stor del beroende på utgångspunkt och produktionsspecifika förutsättningar och måste undersökas vidare genom exempelvis industriförsök.  Eftersom stålverket ställer om produktionen till 2026 kan inte några större investeringar för att minska utsläppen från den äldre produktionen anses vara motiverbar både gällande utsläpp av 𝐶𝑂2 och investeringskostnad. Analyserna av produktionsdata tillsammans med resultatet från litteraturstudierna visade att det fanns flera förbättringsområden och rimliga metoder för stålverket att öka sin skrotinsmältning med syfte att minska utsläppen av 𝐶𝑂2. Genom implementering av dessa metoder som skulle skrotinsmältningen kunna ökas med 2,3 % vilket skulle resultera i en relativ minskning av råstålets 𝐶𝑂2-avtryck med 2,8%.

Food loss and waste (FLW) occurring early in the food supply chain (FSC) leads to increased resource wastage, including land, water, fertilisers, pesticides, fuel, packaging, energy, and labour. Targeting FLW prevention benefits various aspects such as food security, productivity, economic growth, climate change mitigation, resource conservation, and food waste management. Understanding the causes of FLW and their environmental impact is crucial for the design of effective solutions and their prioritisation. The purpose of this study was to investigate the risk factors and underlying causes of FLW in leafy vegetables (LV), mainly lettuce, throughout the Brazilian FSC, spanning from harvest to retail. Additionally, the study evaluated the environmental impact of waste management strategies applicable in the context of the case study. To achieve this, the research methodology encompassed a case study conducted among small-scale producers and retailers in the city of Tupã, Brazil. A comprehensive approach was adopted by integrating a systematic literature review of global FLW causes and those specific to the Latin American context. This approach was complemented by exploratory research, involving interviews with various stakeholders along the FSC, coupled with rigorous root-cause analysis. Moreover, the study employed a Life Cycle Assessment (LCA) methodology to offer an immersive perspective, determining the environmental implications associated with different approaches to treating lettuce waste in the case study. Findings revealed that the root causes of FLW in the case study encompassed normalised unfair trading practices, notably take-back agreement (TBA) conditions, and the absence of supportive policies and incentives for FLW reduction. These root causes manifested in the absence of formal agreements between retailers and local producers, leading to the return of unsold or substandard items without compensation. Furthermore, supermarkets exert power over product quality but evade responsibility for proper storage or encouraging the utilisation of unsold products. Another category of significant causes, designated by the author as "major causes," encompassed causes such as unpreparedness for adverse weather conditions, lack of skilled labour, and stringent visual quality standards. These factors were pivotal risk contributors that potentially motivate various other causes of FLW. To tackle root and major causes of FLW of LV, this study proposed specific measures encompassing fair trade agreements, policy enhancements, protective measures for producers, skill development, and flexible standards. Moreover, by implementing an attributional LCA methodology, the study underscored the importance of source reduction in preventing the environmental impact of food waste for the specific context of the case study. According to the results obtained, for each kg of lettuce that is not produced, 0.065 kg CO2eq are avoided. These findings also highlighted the environmental efficacy of animal feed production, which is a cost-efficient strategy, widely prevalent in the city studied, presents a carbon footprint of -0.013 kg CO2eq/kg of waste. Other common solutions implemented at the case study, such as anaerobic digestion and composting exhibit less favourable carbon footprints, measuring 0.019 and 0.006 kg CO2eq/kg of lettuce, respectively. Landfilling emerges, as expected, as the least desirable option with a considerably higher carbon footprint of 0.423 kg CO2eq/kg. To summarise, this study highlights the environmental advantages of prioritising prevention and higher waste hierarchy levels. It underscores the need for context-specific evaluations when dealing with the intricacies of waste management systems. Moreover, the research emphasises the potential for innovative strategies, multi-stakeholder collaboration, and a holistic approach to address the complex issue of FLW, considering both the environmental impact and practical challenges in a real-world implementation.

Livscykelanalys är en metod som utformades och utvecklades för att kvantifiera miljöpåverkan från produkter och tjänster för mer än trettio år sedan. Sedan dess har den kontinuerligt förbättrats och blivit mer och mer robust. Som tillverkare av kemiska produkter och monomerer använder Arkema livscykelanalys för att mäta sina produkters miljöpåverkan. Detta görs för att förstå enskilda produkters fotavtryck samt företagets övergripande miljöpåverkan. För att göra detta används ISO-normerna 14040 och 14044. Dessa normer anger generiska ramar för LCA-beräkningar men är inte specifika för den kemiska industrin. Med tanke på att metodologiska svårigheter kan uppstå inom den kemiska sektorn har många riktlinjer och rekommendationer publicerats på senare tid. I denna uppsats studeras och jämförs några av dessa riktlinjer. Tillämpningen av dessa metoder utförs på två produkter inom Arkemas portfölj: akrylsyra och etylakrylat, som är byggstenar för många polymerer. Resultaten av utvärderingen visar på områden där förbättringar kan göras. För de studerade produkterna är råvarorna de största bidragande orsakerna. Därför kan det vara fördelaktigt att övergå från petroleumbaserade material till biobaserade. Att välja den minst miljöpåverkande produktionsvägen är också ett sätt att aktivt minska produkternas koldioxidavtryck. / Life Cycle Assessment is a methodology that has been designed and developed to quantify the environmental impacts of products and services more than thirty years ago. Since then, it has been in continuous improvement and becomes more and more robust. As a producer of chemical products and monomers, Arkema uses Life Cycle Assessment to measure the environmental impact of its products. This is done to understand the footprints of individual products as well as the company's overall environmental impact. To do so, the ISO norms 14040 and 14044 are used. These norms set generic frames for LCA calculation but are not specific to the chemical industry. Considering that methodological difficulties can arise in the chemical sector, many guidelines and recommendations are being published recently. In this thesis, some of those guidelines are studied and compared. The application of these methodologies is performed on two products within Arkema’s portfolio: acrylic acid and ethyl acrylate, which are building blocks for many polymers. The results of the assessment reveal areas where improvements can be made. For the products studied, the main contributors are the raw materials. Therefore, transitioning from petroleum-based materials to biobased ones could be beneficial. Additionally, selecting the least impactful production route is also a way to actively reduce the carbon footprint of the products.

This thesis focuses on addressing the challenge of managing the climate impact of system engineering projects within a large global industrial company. The research design is a case study within the selected company, and it integrates qualitative and quantitative methodologies to provide a holistic understanding of environmental challenges. The principal objective is to provide direction on efficient management of system engineering projects’ environmental footprint delivered by large global industrial companies. This is achieved by quantifying greenhouse gas emissions and identifying critical factors that significantly influence environmental outcomes. Based on the results together with the qualitative results from the interviews, effective countermeasures have been developed to reach set science-based emission reduction targets aligned with the Paris Agreement. The research has contributed to a better understanding of the climate impact of system engineering projects, provided guidance on measuring their environmental impact and offered strategies for reducing GHG emissions to mitigate climate change risks. The thesis further delves into various relevant concepts, including system engineering, science-based emission reduction targets, carbon footprint analysis, motivators and barriers for greenhouse gas emissions reductions and the decarbonization of system engineering projects.  The research underscores the importance of user-friendly calculations of CO2e emissions aligned with ISO standards. It also emphasizes the necessity of addressing emissions throughout the value chain and optimizing key components for achieving successful outcomes. Furthermore, standardization and incorporating environmental considerations during the design phases are highlighted as important aspects supporting science-based emission reduction targets. To conclude, this research aims to provide valuable insights into effectively managing the climate impact of system engineering projects in a large global industrial company. It offers practical strategies, recommendations, and considerations to support a company's sustainability goals and environmental commitments.