Examensarbeten för masterexamen
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- PostConnecting Impact and Quality - Prospective Life Cycle Assessment of recycling Carbon Fibre Composites(2024) Gunnarsson, Erik; Kasliwal, Suvidhi; Chalmers tekniska högskola / Institutionen för teknikens ekonomi och organisation; Chalmers University of Technology / Department of Technology Management and Economics; Svanström, Magdalena; Hermansson, Frida; Johansson, MonicaThis thesis investigates the environmental impacts of recycling possibilities of carbon fibre reinforced polymers (CFRP), for which the intended use is carbon fibre tanks in fuel cell electric vehicles (FCEV’s). The research, conducted in collaboration with Volvo Group Trucks Technology, IVL Swedish Environmental Research Institute and Chalmers, builds on a previous thesis by Weiszflog and Abbas (2022) that aimed to explore and analyse the implementation of different hydrogen storage systems and compare their environmental impacts. This study focuses on identifying and evaluating potential commercial viability of the aforementioned recycling methods for CFRP. Each method’s potential to produce high-quality recycled carbon fibres (rCF) suitable for second-life applications are examined through mechanical quality indicators, e.g. tensile strength, tensile modulus, length and diameter of the recovered fibre. The different recycling systems are later compared in a Life Cycle Assessment (LCA), where the environmental impacts are quantified and compared to one another based on the impact assessment methods climate change, cumulative energy demand, human toxicity, and resource use. One of the primary goals of the thesis is to develop a framework for identifying second-life applications for rCF based on the resulting quality indicators after exiting the recycling processes, as well as complementing and adding onto existing inventory data. The study also analyses an exploratory option for recycling of CFRP, comparing the present with a potential 2030 scenario that considers different electricity mixes and their implications for recycling technologies. Another primary aim for this thesis is to condense the large amount of information available on carbon fibre recycling and its resulting mechanical quality into a table that can be used in future assessments. The thesis also aims to act as inventory data for future work related to CFRP recycling. The research concludes that effective recycling of CFRP can significantly reduce the environmental impacts associated with the material’s production and disposal. By implementing improved recycling technologies, either the same industry or neighboring industries, such as nautical or personal vehicles, can use the rCF instead of virgin carbon fibre (vCF), and through the usage make substantial strides towards decarbonisation and addressing the exponentially growing demand for carbon fibres.
- PostDigital Twins in Supply Chain: Catalyzing the change towards Circular Economy(2024) Jensen, Johannes; Panneerselvan, Arunkumar; Chalmers tekniska högskola / Institutionen för teknikens ekonomi och organisation; Chalmers University of Technology / Department of Technology Management and Economics; Agrawal, Tarun; Agrawal, TarunThis research explores the role of Digital Twin, a key technology in Industry 4.0, in facilitating the shift towards a circular economy via Supply Chains. It also addresses the potential obstacles that hinder the integration of Digital Twin into the Supply Chain. Data was gathered through a comprehensive literature review and interviews with researchers and company personnel to understand the degree to which Digital Twins are utilized in their organizations, and how it can guide them towards circularity in their supply chains.The study reveals that Digital Twins can enhance circularity in supply chains by extending the product lifespan through real-time monitoring and predictive maintenance, as well as by effectively tracking products returned by customers. However, implementing Digital Twin technology in extensive network like supply chains is challenging due to factors that complicate real-time data collection and time-consuming and costly process of modeling every asset. Therefore, in such large networks, a Digital Model could be a more practical and cost-effective solution.
- PostEx-ante Life Cycle Assessment of carbonating Green Liquor Dregs for CCUS An early assessment on the prospects of using direct aqueous carbonation on green liquor dregs from the pulp industry for carbon capture, utilization and storage(2024) Olivegren, Harald; Chalmers tekniska högskola / Institutionen för teknikens ekonomi och organisation; Chalmers University of Technology / Department of Technology Management and Economics; Baumann, Henrikke; Shavalieva, Gulnara; Baumann, HenrikkeSince pre-industrial time, the temperature on earth has risen with over 1°C due to human activities. To limit the temperature rise to less than 2°C there is a need of Carbon Capture, Utilization and Storage, CCUS, technologies that collect and store or use CO2 from the atmosphere. However, the existing CCUS technologies are either expensive or ineffective, therefore there is a need to develop new CCUS technologies. This thesis aims to show the possible prospects for CCUS by direct aqueous carbonation of green liquor dregs, GLD, using flue gas from pulp mills. With data from lab experiments and from Smurfit Kappa mill in Pite˚a, a scaled-up model was built to evaluate the maximum yield of sequestered CO2, electrical energy needed to run the carbonation process and the possible avoided emissions from product replacement using the carbonated GLD, cGLD. The results was then scaled up to the total GLD production in Sweden in 2022. Three scenarios were studied, 1.The cGLD was only filtered and assumed to be land-filled, 2.The cGLD was dried and used to substitute clinker and 3.The cGLD was dried and used to substitute gravel. The results show that scenario 2 has the highest negative emissions of -0.756 ton CO2 per ton of input GLD, compared with roughly -0.176 ton CO2 per ton input GLD for both scenario 1 and 3, using Swedish electricity mix for the emissions from electricity generation. The most energy intensive process step was drying, which in case 2 and 3 stood for 96% of the electricity use. When scaled up to incorporate carbonating all GLD produced in Sweden in 2022, the maximum negative emissions for the 2nd scenario summed up to 0.31% of all emissions from Sweden and 24% of the emissions from the total Swedish pulp and paper industry. A sensitivity analysis was performed by changing the electricity generation to be from general EU-mix. The impact on scenario 1 was minimal but for scenarios 2 and 3, the electricity mix had significant impact with total negative emissions of -0.627 and -0.005 ton CO2 per ton input GLD respectively, due to the high energy use in the drying step. Since this is a novel technology, no earlier studies regarding carbonation of GLD has been published. This report should therefore only be viewed as an indication that there could be noteworthy benefits of carbonating GLD for CCUS, with significant negative emissions of 0.31% of Sweden’s total emissions.
- PostImproving Transportation Efficiency: Cost Comparison Between Single Trailer and High- Capacity Transport in Container Road Freight(2024) Zhu, Yixue; Li, Junyang; Chalmers tekniska högskola / Institutionen för teknikens ekonomi och organisation; Chalmers University of Technology / Department of Technology Management and Economics; Cardenas Barbosa, Ivan Dario; Von Corswant, FredrikThis thesis examines the use of High-Capacity Transport (HCT) vehicles in container logistics, as well as the use of dry ports and last mile efficiency. The study focuses on comparing single and double trailer configurations, examining their respective advantages in terms of cost-effectiveness, operational efficiency, and environmental sustainability. Meanwhile dry ports, as key hubs for relieving congestion in seaports and streamlining the distribution process, focus on specific situations suitable for implementation. The thesis assesses the economic viability of HCT vehicles and dry ports in transport scenarios through a combination of literature review, case studies, and data analysis. The results of the study show that the combination of HCT vehicles and strategically located dry ports can significantly reduce transport costs, improve supply chain efficiency, and support more sustainable logistics operations. The study provides insights into optimizing container transport for long-haul and last-mile movements, contributing to the development of more efficient and environmentally friendly freight transport solutions.
- PostBiodiversity at Volvo Group Real Estate Identification of a suitable biodiversity framework and action plan for enhanced biodiversity(2024) Brunke, Julia; Chalmers tekniska högskola / Institutionen för teknikens ekonomi och organisation; Chalmers University of Technology / Department of Technology Management and Economics; Molander, Sverker; Johansson, Henrik; Bengtsson, CeciliaThis master’s thesis was done by request of Volvo Group Real Estate (VGRE) in Gothenburg, Sweden. The aim of this master’s thesis was to decide upon a framework for biodiversity assessment and to develop an action plan for biodiversity for VGRE. A literature study in which criteria was found in order to identify a suitable biodiversity assessment framework was conducted. In addition, a field study, during which an assessment of VGRE:s approach to biodiversity was made. The field study took place at the VGRE site in Tuve, Sweden. The research questions in this master’s thesis gained insight into the data needed when performing a biodiversity assessment and which framework for biodiversity assessment that is most suitable for VGRE. They also investigated what the direct drivers of biodiversity loss that VGRE:s site in Tuve contributes to, how VGRE can reduce their negative impact on biodiversity at their site in Tuve and what actions that can be put in place in order to enhance and/or restore biodiversity at the site. During the master’s thesis it was found that a recurring issue for businesses and industries is that there are many variables and corresponding complications when performing biodiversity assessments. The frameworks for biodiversity assessments, developed by various organisations (both governing and independent), are more complicated than they make light of. There is a certain level of knowledge and expertise needed to implement and/or supplement the frameworks used for biodiversity assessments. The literature and field study was iterative and the selected framework was Biodiversity Net Gain (BNG). In addition, the framework should be able to handle time and resource constraints that may appear while leaving space for the inclusion of tools for continuous reassessment and evaluation. Therefore, in addition to BNG the company will need to adhere to the Mitigation Hierarchy. It was also suggested that the company will use the State, Pressure and Result (SPR) framework to find suitable indicators to monitor their efforts in a quantifiable way. The criteria that the selected framework needed to adhere to was decided upon during both the literature study and the field study. The action plan was divided into two parts, one for areas that are to be exploited and one for areas that are already exploited. In addition, good principles, are included as guidelines for the company to follow.