par Towa Kouokam, Edgar Battand 
Président du jury Bauler, Thomas
Promoteur Achten, Wouter
Co-Promoteur Zeller, Vanessa
Publication Non publié, 2021-03-30
Président du jury Bauler, Thomas
Promoteur Achten, Wouter
Co-Promoteur Zeller, Vanessa
Publication Non publié, 2021-03-30
Thèse de doctorat
| Résumé : | We live on a planet with finite natural resources and human activities creating pressures on the environment. The Circular Economy (CE) is gaining momentum as a means to cope with the environmental pressures from human activities. One of the main elements of CE is to maintainproducts and materials at their highest application level as long as possible, while minimising the environmental impact. Hence, a CE implies to minimising the natural resource consumption, reducing waste generation, rethinking waste management (WM), reinforcing the recycling andreuse of products and materials, in tandem with reducing emissions. Measuring is key to take the first steps for a transition towards a CE. This includes the quantification of the environmental pressures of human activities in a CE context as well as the quantification of the degree ofcircularity, i.e. how much materials are recovered from waste. Several tools and methods exist to measure and monitor how circular an economy is, but it is the input-output (IO) model that is of interest in this thesis. The general objective of this thesis is twofold: 1) develop a suitable IO model and 2) demonstrate the applicability and limits of that model. For the second point several applications (or tests) of the model are carried out with different types of analyses. The focus on the subnational level is justified by the Belgian legal and policy context in which WM and CE are mostly regional competences. This thesis has developed the first multiregional hybrid input-output (MRHIO) representing theBelgian subnational level for 2011. This development constitutes the major methodological contribution of this thesis. The critical scientific literature review that was carried out in this thesis showed that the MRHIO model is conceptually the most suitable model for WM and CE analyses at the macro scale. The developed model has been applied to analyse the environmental pressures induced by the regional household demand. Three main applications of the model were performed: 1) carbon and waste footprint analyses, 2) assessment of the degree of circularity and 3) modelling CE scenarios. The 2nd point has necessitated the development of two indicators to measure the degree of circularity considering the trade of waste for treatment between regions.The results of these analyses indicate similar challenge towards the prevention and reduction of waste in the Belgian regions as there are no significant variations in the carbon and waste footprints between the regions. However, this thesis does not investigate the main drivers of these regional differences. Future research should be dedicated to that. Also, CE has a multiregional face that should be considered when defining and implementing CE strategies and targets. This thesis shows that more than half of environmental pressures of regions occurred in the regions, as well as the pressures effects inherent in the interrelationships between Belgian regions. In addition, measuring the circularity and planning the CE strategy of a region should integrate region-specific information such as the geographical context, the production and consumption landscape and the dependency/autonomy regarding waste treatments. The results of this thesis impart that the role of regions like Brussels (urbanised and service-oriented) in a CE model is mainly a provider of recoverable materials compared to regions like Flanders that have the capacity to producerecovered materials. Lastly, the relatively young age and lack of maturity of MRHIO model seems to be a limiting factor when conducting complex analyses such as CE scenario analyses. Therefore, more applications of MRHIO models should be encouraged, which will in turn triggerimprovements of the model. This thesis supports the regional and federal policymaking processes providing specific information on key waste fractions, waste treatments, products consumed, material categories and CE strategies that deserve priority actions. Key information to enhance the waste data monitoringpractices at the regional level with effects at the federal level has also been unveiled. This thesis has also provided insights that could substantiate CE policies and help policymakers to clarify which kind of circularity is aimed or intended for Belgian regions. Lastly, this thesis can be seen as a partial solution towards a WM and CE monitoring framework through the double hatted model (IO and supply and use versions) at the Belgian subnational level. Therefore, this thesis also stresses that regions should take more concerted efforts in producing and updating MRHIOT at the subnational level |
