Life cycle assessment of a mobile recycling centre in Gothenburg
Examensarbete för masterexamen
Industrial ecology (MPTSE), MSc
bulky waste. One of the five recycling centres in Gothenburg is Högsbo recycling centre (RC). The recycling centre is located in the west part and manages the largest amount of waste of all the recycling centres in Gothenburg. Because of the high pressure on the recycling centre and the transport distances from the households to the stationary RC there is interest to implement a mobile RC. The aim of this master´s thesis is to examine if there is any change in environmental impact through the introduction of a mobile RC in the west districts of Gothenburg. The aim is met through a life cycle assessment, using the modelling program Gabi Professional 2017 Student version. The functional unit in the study is as follows: the average management of bulky waste produced by one of Gothenburg’s citizens, living in the districts of Askim-Frölunda-Högsbo and west Gothenburg, during one year. The impact categories considered in the study are acidification, eutrophication and global warming. Three scenarios are modelled, depending on various waste management methods. The first scenario, stationary RC, entails that there only is a stationary RC available in Askim-Frölunda-Högsbo and west Gothenburg. In the second scenario, implementing mobile RC, an assumed mobile RC is implemented, visiting seven various locations around the aforementioned districts five times during one year. In the latter aforementioned scenario, 10 percent of the citizens visit the mobile RC two times a year and 95 percent still visit the stationary RC. In the third scenario, mobile RC, 100 percent of the citizens visit the mobile RC two times a year. Furthermore, a system expansion is made to manage an assumed increase of reusable textile. In the system expansion, the second scenario in combination with the impact from textile is compared with the first scenario. The study relies on several assumptions, but can be seen as an indication of the environmental impacts of implementing a mobile RC. The study implies that the environmental impact decreased in the implementing mobile RC- and mobile RC scenarios, even though the total average transport distance of waste increased in the mentioned scenarios because of the implementation of the mobile RC. In a more realistic scenario, implementing mobile RC, environmental impacts are only slightly lower than in the stationary RC scenario, were as the environmental impacts are clearly lower in the theoretical best-case scenario, mobile RC. The decrease in environmental impact is partly due to the shift in transportation mode from private cars to walking and biking. Also, the total transport distance by car is shorter in the implementing mobile RC- and mobile RC scenario compared to the stationary RC scenario, which reduces the environmental impact. However, the total transport distance with truck, powered by HVO, has increased, which implies that trucks are more environmental beneficial than cars in this study. It can be concluded that the implementation of a mobile RC has a low environmental benefit if few citizens use it, as in the implementing mobile RC scenario. The environmental benefit of introducing a mobile RC is increased when more citizens use the recycling centre, as in the mobile RC scenario. Nevertheless, this is only valid in the case the citizens also decrease their visits to the stationary RC. However, the decrease in environmental impact is overestimated in the mobile RC scenario. The transport from the mobile RC to the stationary RC would have to increase because of limited storage capacity. The study also shows that a collecting system that enables an increase in collected reusable textiles has a significantly high potential to reduce the environmental impacts studied. Other geographical areas and other assumptions on how the mobile RC is operated may change the results. Thus, the results are only valid under the specific conditions given in this report.
Annan naturvetenskap , Other Natural Sciences