| dc.description.abstract | To mitigate climate change and achieve the United Nations Sustainable Development Goals (SDGs), the world must shift from the current linear economy to a circular economy system focused on the 3Rs: reduce, reuse and recycle.
In a context where aluminium production is responsible for 3.5% of global electricity consumption, the development of an energy-efficient material flow analysis focused on assessing the sustainability of the aluminium cycle can make an important contribution to the achievement of the 12th SDG, aimed at "ensuring sustainable consumption and production patterns", the 9th SDG focused on "building resilient infrastructure, promoting inclusive and sustainable industrialisation and fostering innovation" and the 13th SDG based on "taking urgent action to combat climate change and its impacts".
In addition, 31% of the aluminium produced in the world comes from recycling in the industrial sector and from waste, demonstrating the huge potential of recycling and circular economy projects in the field of aluminium. After studying the current aluminium flow situation in Norway, it has been concluded that the aluminium industry in terms of sustainability is a multifaceted issue that requires a comprehensive study from cradle to grave.
This thesis aims to map the aluminium flow in Norway, with emphasis on the waste flow, the flow between different sectors and the accumulation of aluminium in society. The software for substance flow analysis called Stan was used to carry out the material flow analysis of aluminium scrap in Norway. To obtain the necessary data, a survey is carried out with seventy-one possible responses to the sixty-three companies in the Norwegian aluminium industry. The maximum response time for the survey was less than ten minutes, as the survey selected the following questions depending on the answer given. In the end, thirty new companies participated in the project, three of them declined participation and twenty of them were discarded due to the low aluminium flows they handled, which were practically negligible at the level of Norway as a country. However, a good future line for this project is to complete the information from the companies that have not participated in this project. The main results of the material flow analysis were the following:
In the year 2021, the import of alumina to Norway was 1.721.937 tons, the aluminium production accounts for 882.163 tons of aluminium ingots in 2021, to which must be added an import of 667.958 tons. In turn, semi-finished manufacturing accounts for 1.440.651 tons in 2021, of which 92.43% is exported. In this way, the aluminium final products flow accounts for 100.552 tons, of which 80.12% are also exported. The pre-consumer scrap generated in this process plus the scrap inflow coming from society and imported make a scrap inflow stream towards the scrap recovery sector of 50.120 tons. After recycling the scrap inflow, 99.81% of the input is transformed into recycled billets, of which 90.01% is exported. Finally, the difference between incoming scrap and recycled billets corresponds to waste that is sent to incineration plants, which meant a flow of 93.9 tons in the year 2021. The total import of the process were 2.393.095 years and the export was 1.571.627 tons. To conclude, the future directions of this project are set out at the end of the conclusions. | |