Thesis
Reference
Explaining the phenomenon of waste allocation among waste treatment operations: case studies, concepts & methods
C BERGERON, Francis
Abstract
Cette thèse aborde principalement le phénomène de l'allocation des déchets entre filières de traitement des déchets. Les connaissances obtenues d'une étude de cas exploratoire sur la gestion du déchet de bois en Suisse et d'une revue de la littérature scientifique ont conduit à développer la méthode analytique du processus d'allocation des déchets. Cette méthode est mise en œuvre dans une étude de cas sur l'allocation des déchets ménagers dans le Canton de Genève. Elle constitue une méthode simple, reproductible et accessible pour l'évaluation des systèmes de gestion des déchets. Cette thèse se poursuit avec la création d'une méthode hybride pour l'évaluation des politiques de gestion des déchets et de ses instruments. Cette méthode est appliquée à l'évaluation des politiques genevoises de tri des déchets urbains qui constitue une approche fiable pour mesurer l'efficacité des instruments politiques.
C BERGERON, Francis. Explaining the phenomenon of waste allocation among waste treatment operations: case studies, concepts & methods. Thèse de doctorat : Univ.
Genève, 2017, no. Sc. 5115
DOI : 10.13097/archive-ouverte/unige:97323 URN : urn:nbn:ch:unige-973238
Available at:
http://archive-ouverte.unige.ch/unige:97323
Disclaimer: layout of this document may differ from the published version.
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Section Physique
Institut d’économie et économétrie
FACULTÉ DES SCIENCES Professeur M. Patel FACULTÉ D’ÉCONOMIE
ET MANAGEMENT Docteur F. Romerio-Giudici
Explaining the Phenomenon of Waste Allocation among Waste Treatment Operations: Case Studies, Concepts & Methods
THÈSE
présentée à la Facuculté des Sciences de l’Université de Genève pour obtenir le grade de Docteur ès Sciences, mention Sciences de l’environnement
par
Francis C BERGERON
de
Laval (Québec, Canada)
Thèse N° 5115
GENÈVE
Institut des Sciences de l’Environnement 2017
Droits d’auteur
Les citations tirées de cette thèse de doctorat ne sont permises que dans la mesure où elles servent de commentaire, référence ou démonstration à son utilisateur. La citation doit impérativement indiquer la source et le nom de l’auteur. La loi fédérale sur le droit d’auteur est applicable.
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Foreword and contents
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Remerciements
À la fin de cette longue et enrichissante aventure, il est maintenant temps de prendre du temps pour témoigner ma sincère gratitude aux différentes personnes qui ont contribué à leur manière à la réalisation de cette thèse.
Je tiens d’abord remercier Franco Romerio-Giudici qui, sans son soutien, cette thèse n’aurait pas pu être possible. Merci de m’avoir accueilli au sein de ton groupe et de m’avoir accordé ta confiance. J’ai grandement apprécié notre collaboration et tes judicieux conseils. De plus, je te suis très reconnaissant d'avoir mis à ma disposition tes moyens financiers. Ceux m’ont permis de me perfectionner dans différentes universités européennes et, donc, de réussir cette thèse.
Arrivé en millieu de parcours, je remercie profondément Martin Patel d’avoir accepté la direction formelle de ma thèse. Tu as su parfaitement bien
“challenger” mes recherches. Merci pour ta disponibilité, ton investissement et ton exigeance. Ton aide a grandement contribué à l’amélioration de la qualité du contenu de cette thèse.
Je souhaite ensuite exprimer ma sincère gratitude à Martin Beniston pour m’avoir donné la possibilité de réaliser cette thèse au sein de l’Institut des Sciences de l’Enviromment.
Merci à Suren Erkman et Christian Ludwig, qui en plus de faire partie de mon jury de cette thèse, ont su me donner de judicieux conseil sur mes travaux.
Au contraire des pratiques usuelles de l’université, cette thèse fut financée principalement par mes propres moyens. Ainsi, j’ai fait le choix d’avoir une activité professionnelle parallèle à mes travaux de recherche. Je souhaite remercier mes différents employeurs pour m’avoir accordé leur confiance et pour leur grande compréhension par rapport à mes engagements liés à cette thèse. Par conséquent, je souhaite souligner ma grande reconnaissance à éco21 des Services Industriels de Genève, au Secrétatirat des Conventions de Bâle, Rotterdam et Stockholm du Programme des Nations Unies pour l’Environnement, à équiwatt des Services Industriels de Lausanne et au Contrôle financier de la Ville de Genève. Merci à mes différents responsables : Cédric Jeanneret, Frédique Haessig, Wilfrid Atgé, Pascale Le Strat, Gilles Garazi, Anna Priceputu, Swati Rastogi Mayor, Nicolas Waelti et Maxime Chrétien.
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Enfin, je souhaiterais remercier les diverses personnes qui m’ont donné un coup de pouce: Maura Brunetti, Gregor Fey, Violeta Djambazova, Géraldine Pflieger, Jean-Luc Bertollet, Guillaume Massard, Jérôme Faessler, Michel Bourdonnet, Nils Rademacher, Pierre Dario Calzolari, Guénolé Marquet et Matthieu Raeis.
Comme tous doctorants et toutes doctorantes, j’ai reçu le soutien de ma famille et tous mes amis de Montréal et de Genève. Je souhaiterai les remercier de tout coeur.
Encore MERCI à toutes et tous! Bonne et plaisante lecture!
.
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Résumé
Les systèmes de gestion des déchets diffèrent considérablement dans le monde en raison des différences dans la génération des déchets et de leur traitement. Au cours des quatre dernières décennies, les systèmes de gestion des déchets ont connu des changements majeurs dans les pays développés. Ils fournissent dorénavant des ressources secondaires et de l’énergie. Cette évolution a provoqué une concurrence croissante entre opérations de traitement. Dans certains pays et pour certains types de déchets, cela a entrainé la captation des déchets disponibles par le secteur de l’incinération au détriment de leur recyclage. Dans ce contexte, cette thèse aborde le phénomène de l’allocation des déchets entre opérations de traitement des déchets. Elle cherche à améliorer notre connaissance scientifique sur ce phénomène de l’allocation des déchets.
Cette thèse commence par une étude de cas exploratoire sur la gestion de déchets de bois en Suisse. Cette étude de cas fut choisie, car le gouvernement suisse reconnaît que la promotion de l’usage du déchet bois aux fins énergétiques n’est pas coordonnée comme une étape finale d’une utilisation efficiente en cascade du bois. La modélisation du métabolisme du bois et du déchet de bois dans l'anthroposphère suisse, combinée avec une analyse documentaire sur les pratiques actuelles de gestion du déchet de bois, démontre la cohérence de la gestion actuelle du déchet de bois en Suisse.
Ainsi, la gestion actuelle constitue un équilibre adéquat entre les différents objectifs des politiques sectorielles et stratégies transversales des autorités suisses. Les résultats obtenus démontrent aussi que le déchet de bois peut devenir une ressource secondaire significative pour atteindre les cibles suisses liées aux réseaux de chaleur, à la production d'électricité à partir de la biomasse et des déchets ainsi qu’à la réduction des émissions de GES dans le secteur du bâtiment et de l'industrie.
Par la suite, les connaissances obtenues de cette étude de cas avec une revue de la littérature scientifique additionnelle ont conduit à définir le processus d'allocation des déchets, c’est-à-dire la répartition des déchets entre opérations alternatives de traitement des déchets. De plus, elles ont permis de créer la méthode analytique du processus d'allocation des déchets qui utilise à
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la fois une approche qualitative et quantitative. En outre, elle utilise le principe de l'équilibre de masse lors de l'application de la méthode d'analyse des flux de matière. La méthode analytique possède un cadre conceptuel et une démarche analytique. Premièrement, le cadre conceptuel repose sur un modèle descriptif et explicatif. Le modèle descriptif sert à décrire et à classer les systèmes de gestion des déchets au travers de deux dimensions: 1) les méthodes adoptées de traitement des déchets et 2) les échanges de déchets entre systèmes. Ce modèle est ensuite inséré dans un modèle explicatif. Il sert à expliquer et à prédire le fonctionnement du système de gestion des déchets.
Deuxièmement, la démarche analytique constitue une procédure étape par étape pour la mise en œuvre empirique et transparente de la méthode par les professionnels et les chercheurs.
Cette méthode analytique est mise en œuvre dans une étude de cas sur l'allocation des déchets ménagers dans le Canton de Genève (Suisse) pour la période 2002-2013. Ainsi, le modèle descriptif montre des flux d'importation et d'exportation peu élevés qui entrent et sortent du système de gestion des déchets ménagers à Genève (c'est-à-dire moins de 35% de la totalité des déchets traités). Le traitement des déchets est dominé par sa valorisation énergétique (c'est-à-dire plus de 60% des déchets traités). L’analyse indique que la diminution des importations de déchets est la principale raison de la réduction des déchets traités par valorisation énergétique au cours du temps.
Par conséquent, le modèle explicatif se concentre sur les différents déterminants qui agissent comme barrières aux importations de déchets. Les deux principaux sont l'ouverture d'une nouvelle usine d'incinération à l'extérieur de Genève et les restrictions aux importations de déchets par les autorités genevoises. Ces barrières ont ainsi provoqué la diminution des déchets traités par valorisation énergétique à l’incinérateur de Genève. Cette réduction obligea les autorités cantonales à augmenter la taxe d'incinération et à introduire une taxe d'enfouissement afin d’assurer les revenus nécessaires au financement des infrastructures cantonales de tri cantonal et à la sensibilisation.
La principale valeur ajoutée de la méthode analytique du processus d'allocation des déchets est de fournir une méthode d’évaluation des systèmes de gestion des déchets simple, reproductible et accessible pour les praticiens et les chercheurs. Son application offre une connaissance approfondie de ces systèmes et de leur évolution au cours du temps. Il s’agit d’informations utiles
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et pertinentes pour la planification de la gestion des déchets, l’évaluation des politiques des déchets, les recherches académiques et la prise de décision.
Cependant, la méthode doit être mise en œuvre dans d'autres études de cas pour s’assurer de l’applicabilité du cadre conceptuel. De plus, elle reste inapplicable pour un système de gestion des déchets, où les opérations de tri sont situées à l'extérieur des frontières géographiques du système. L’utilisation de cette méthode dans une première étude empirique a permis d'explorer un autre domaine de recherche.
Cette thèse se poursuit avec l'élaboration d'une méthode pour évaluer les effets d’une politique de déchets et de ses instruments. Cette méthode hybride d’évaluation repose sur une analyse combinée de l'évolution des ressources mobilisées par les acteurs et l’état d’un système de gestion des déchets. Elle est mise en œuvre dans une étude de cas qui vise à évaluer les instruments politiques utilisés pour le tri des déchets ménagers à Genève. Les résultats démontrent l'efficacité des instruments politiques utilisés à Genève pour le tri des déchets ménagers. Ils montrent aussi l’existence d’une interaction dynamique entre les ressources utilisées et l'état du système de gestion des déchets. Ainsi, la méthode fournit des informations sur la manière dont la modification d'un système de gestion des déchets affecte les ressources utilisées par les acteurs. Cependant, il existe un risque de simplification excessive de la méthode, car elle ne prend pas compte explicitement de la motivation des acteurs dans l'utilisation des ressources. En outre, la méthode constitue une approche fiable pour mesurer l'ampleur des impacts des instruments politiques et leur efficacité dans le cadre de l’évaluation des politiques des déchets, mais elle ne permet pas d'en évaluer leurs efficiences économiques.
Les études de cas ont permis de fournir plusieurs recommandations pour les décideurs. Pour améliorer l'exploitation des déchets de bois en tant que source d'énergie, le tri et le prétraitement des déchets de bois doivent précéder son traitement thermique. En outre, la cogénération doit être utilisée, où le contexte le permet et la viabilité économique est assurée. La conception de nouvelles chaudières à déchets de bois doit tenir compte à la fois des ressources disponibles localement et de la demande de chaleur. En ce qui concerne l'utilisation des instruments politiques pour le tri des déchets ménagers, un mix basé sur la sensibilisation et les instruments d'infrastructure constitue un moyen efficace pour promouvoir le tri des déchets. Les
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mécanismes financiers basés sur une taxe d'élimination ne constituent pas une approche durable pour financer les coûts d'exploitation d'une infrastructure de tri. Finalement, les instruments incitatifs forment une bonne approche pour encourager l'introduction de prestations de tri par les autorités municipales.
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Resume/Summary
Waste management systems differ substantially across the globe due to differences in the generation of waste and its treatment. During the last four decades, waste management systems have undergone major changes in developed countries. They now provide both energy and secondary resources.
This evolution has caused growing competition among the waste treatment options. In some countries and for some waste streams, this has led to incineration of an increased share of the available waste at the expense of recycling. Against this background this thesis deals with the phenomenon of waste allocation among treatment operations. It aims to improve our scientific knowledge about the phenomenon of waste allocation.
The thesis begins with an exploratory case study on waste wood management in Switzerland. This case study was chosen because the Swiss government acknowledges that the promotion of waste wood for energy purposes is not coordinated as final step of resource-efficient cascading. The modelling of the metabolism of wood and waste wood in the Swiss anthroposphere, combined with a documentary analysis of the current practices of waste wood management, demonstrates the coherence of current waste wood management in Switzerland. Thus, the current management constitutes an adequate balance between the various goals of the sectorial policies and the crosscutting strategies of the Swiss authorities. The obtained results also underline that waste wood could become a significant secondary resource in achieving the Swiss targets for the district heating, electricity production from biomass and waste as well as GHG emission reduction from the building and industry sector.
The insights obtained from this case study, in combination with an additional literature review, lead to the definition of the waste allocation process, i.e. apportioning of waste among alternative waste treatment operations. They also allow to create an analytical method of waste allocation process, using both a qualitative and quantitative approach. Moreover, it makes use of the mass balance principle when applying the material flow analysis method. The analytical method consists of a conceptual framework and an analytical approach. Firstly, the conceptual framework relies on a descriptive model and an explanatory model. The descriptive model serves to describe and classify the waste management systems through two dimensions:
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1) the adopted methods of waste treatment and 2) the exchange of waste between systems. This model is then inserted into an explanatory model. It serves to explain and to predict the operation of the waste management system. Secondly, the analytical approach is a step-by-step procedure for the empirical implementation of the method for professionals and researchers.
This analytical method is implemented in a case study on the allocation of household waste in the canton of Geneva (Switzerland) in the period 2002–
2013. The descriptive model shows low import and export flows entering and leaving the household waste management system in Geneva (i.e., less than 35% of the whole treated waste). The waste treatment is dominated by energy recovery (i.e., more than 60% of the treated waste). The analysis pinpoints the decrease of waste imports as the main reason for the reduction of waste treated by energy recovery over time. Therefore, the explanatory model focusses on the different determinants that act as barriers to waste imports. The two main determinants are the opening of a new incineration plant outside Geneva and the restriction on waste imports by Genevan authorities. These barriers caused the decrease of the waste treated by energy recovery in the Genevan incineration plant. This decrease forced the cantonal authorities to raise the incineration tax and to introduce a landfill tax, to ensure the revenue required for financing the cantonal sorting infrastructure and for awareness raising.
The main value added of this analytical method is to provide a simple, reproducible and comprehensive assessment method of waste management systems for practitioners and researchers. Its application has offered in-depth knowledge of these systems and their evolution over time. This is useful information for waste management planning, waste policy evaluation, academic research and decision-making. However, the method needs to be implemented in further case studies to ensure broader applicability of the conceptual framework. In addition, it cannot be applied to a waste management system, if its sorting operations are located outside geographical borders of the system. The utilisation of this method in a first empirical study has allowed to explore another field of research.
This thesis continues with the development of a hybrid method to assess the effects of waste policy and its instruments. This evaluation method relies on a combined analysis of the evolution of the resources mobilised by actors and of the state of the waste management system. It is implemented in a case study which aims to assess policy instruments used for household waste
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sorting in Geneva. The results demonstrate the effectiveness of the instruments used for waste sorting in Geneva. They also show the dynamic interaction between the resources mobilised and the state of the waste management system. Thus, the method provides information on how the modification of a waste management system affects the resources used by actors. However, there is a risk of oversimplification of the method, because it does not explicitly take into account the motivation of actors using the resources.
Moreover, the method represents a reliable approach to measure the extent of impacts and the effectiveness of policy instruments in the framework of waste policy evaluation, while not allowing to evaluate their economic efficiency.
The case studies have allowed to develop various recommendations for decision-makers. To improve the exploitation of waste wood as an energy source, sorting and pre-treatment must precede its thermal treatment. In addition, cogeneration technology must be applied, where the context permits to do so and economic viability is ensured. The design of new waste wood incineration systems must take into consideration both the locally available resources and the heat demand. Regarding the use of policy instruments for household waste sorting, a mix based on awareness raising and infrastructural instruments is an effective way to promote waste sorting. The financial mechanisms based on a disposal tax do not constitute a sustainable approach to finance the operating costs of a sorting infrastructure. Finally, the incentive instruments constitute an appropriate approach to encourage the introduction of sorting activities by municipal authorities.
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Contents
Foreword and contents ... iii
Remerciements ... v
Résumé ... vii
Resume/Summary ... xi
Contents ... xiv
Acronyms and abbreviations ... xix
Chapter 1 Overall introduction ... 1
1.1 Issues, environment and method ... 3
1.1.1 From waste generation to waste treatment ... 3
1.1.2 The competitive use of waste between waste recovery operations . 5 1.1.3 The environment of the waste allocation: Waste management system ... 7
1.1.4 Methods and tools for the study of the phenomenon of waste allocation ... 10
1.2 Objectives and structure of the thesis ... 12
1.2.1 Objectives and scopes ... 12
1.2.2 Interdisciplinary perspective... 13
1.2.3 Structure of the thesis ... 13
SECTION I CASE STUDY ON WASTE WOOD MANAGEMENT IN SWITZERLAND ... 21
Chapter 2 Assessment of the coherence of the Swiss waste wood management ... 23
2.1 Introduction ... 25
2.2 Background and literature review ... 27
2.3 Materials and methods ... 28
2.3.1 Research design for the quantitative approach ... 28
2.3.2 Research design for the qualitative approach... 32
2.4 Results and discussion ... 33
2.4.1 Model results and quantitative data analysis ... 33
2.4.2 Qualitative analysis of the waste wood management in Switzerland ... 37
2.4.3 Coherence of the waste wood management ... 39
2.5 Conclusions ... 40
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Chapter 3 Long-term assessment of energy and climate impacts of waste wood
recovery in Switzerland ... 43
3.1 Introduction ... 45
3.1.1 From wood utilisation to waste wood generation ... 45
3.1.2 Waste wood management in the European Union and Switzerland ... 46
3.1.3 Objective and scope ... 49
3.2 Materials and methods ... 51
3.2.1 Definition and conceptualisation of the model ... 51
3.2.2 Scenario definition for Swiss energy recovery from waste wood . 53 3.2.3 Output data conversion to additional climate and energy indicators ... 55
3.2.4 Method on the decision-making model ... 56
3.3 Results ... 57
3.3.1 Scenario analysis of waste wood generation, energy production and GHG emissions reduction ... 57
3.3.2 Contribution of energy recovery from waste wood to the Swiss policy objectives ... 62
3.3.3 Results on the decision-making model ... 64
3.4 Discussion ... 65
3.5 Conclusions ... 68
Chapter 4 Concluding remarks on Section I ... 71
SECTION II WASTE ALLOCATION PROCESS: ANALYTICAL METHOD AND CASE STUDY ... 79
Chapter 5 Analytical method of waste allocation in waste management systems: Concept, method and case study ... 81
5.1 Background ... 83
5.2 Aims and interdisciplinarity ... 85
5.3 Method ... 86
5.3.1 Purposes and components ... 86
5.3.2 The conceptual framework of WAP ... 87
5.3.3 Analytical approach of AMWAP ... 96
5.4 Result: Case study on household WM in Geneva (Switzerland) ... 97
5.4.1 Objectives and unit of analysis ... 97
5.4.2 Results from the descriptive model... 98
5.4.3 Results from the explanatory model ... 103
5.5 Discussion ... 107
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5.6 Conclusion ... 109
Chapter 6 Concluding remarks on Section II ... 111
SECTION III HYBRID METHOD FOR WASTE POLICY ASSESSMENT ... 117
Chapter 7 Waste management assessment in Geneva through material system analysis and the resources mobilised ... 119
7.1 Introduction ... 121
7.2 Material and methods ... 122
7.2.1 Study area and Genevan household waste ... 122
7.2.2 Methods ... 122
7.3 Results and discussion ... 125
7.3.1 Resources used by the household WM system in 2002 ... 125
7.3.2 Evolution of the household WM system and the resources used until 2013 ... 130
7.3.3 Effects and lessons learned ... 134
7.4 Conclusions ... 137
Chapter 8 Multi-method assessment of household waste management in Geneva regarding sorting and recycling ... 139
8.1 Introduction ... 141
8.2 Case study description and methods ... 143
8.2.1 Geographic and economic context ... 143
8.2.2 Methods ... 144
8.3 Results and discussion ... 148
8.3.1 Evaluation of the household WM in Geneva ... 148
8.3.2 Situation analysis by SWOT analysis ... 159
8.3.3 Strategy formulation ... 162
8.4 Conclusions ... 167
Chapter 9 Concluding remarks on Section III ... 169
Chapter 10 Overall conclusions ... 175
10.1 Brief overview of the thesis ... 177
10.2 Main theoretical and methodological contributions ... 177
10.3 Summary of the recommendations relative to the assessment ... 179
10.3 Limits and further research ... 181
References ... 179
APPENDIX ... 219
Appendix A to the Chapter 2 ... 221
A.1 Additional information on the methodology ... 223
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A.1.1 Modelling the metabolism of wood and waste wood with STELLA
... 223
A.1.2 The forcing variables ... 224
A.1.3 The transfer coefficients ... 225
A.1.4 The residence time of wood in the anthroposphere ... 225
A.1.5 Calibration of the waste wood generation ... 227
A.1.6 Description of the scenario assumptions ... 228
A.2 Conversion methodology of the output data ... 228
A.2.1 Output data conversion into energy indicators ... 229
A.2.2 Output data conversion into climate indicators ... 229
A.3 Results on the climate and energy impacts ... 230
Appendix B to the Chapter 3 ... 235
B.1 Additional information on the methodology ... 237
B.1.1 Modelling of the metabolism of wood and waste wood ... 237
B.1.2 Forcing variables... 238
B.1.3 Transfer coefficients ... 239
B.1.4 Lifespans of wood products ... 242
B.1.5 Calibration of the waste wood generation ... 242
B.1.6 Assumption of the waste wood treatment options ... 242
B.2 Methodology for the conversion of the output data ... 243
B.2.1 Output data conversion to climate and energy indicators ... 243
B.2.2 Output data conversion into energy indicators ... 244
B.2.3 Output data conversion into climate indicators ... 245
B.3 Scenario description and detailed results ... 248
B.4 Maximin formulation and decision-making model ... 258
B.5 Model description in Stella ... 260
Appendix C to the Chapter 5 ... 269
C.1 Supplementary data on the conceptual framework ... 271
C.1.1 Supplementary data on the concept of the waste allocation process (WAP) ... 271
C.1.2 Supplementary data on the descriptive model ... 275
C.2 Supplementary data on the analytical approach ... 279
C.3 Illustrative case study for the assessment of the household waste management system of the canton of Geneva for the period 2002–2013 282 C.3.1 Supplementary material on the unit of analysis ... 282
C.3.2 Supplementary material on the application of the descriptive model ... 287
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C.3.3 List of the stakeholders interviewed ... 293
Appendix D to the Chapter 8 ... 295
D.1 Supplementary data on the case study and the results ... 297
D.1.1 Waste streams selected for the case study ... 297
D.1.2 Resources mobilised for household waste management ... 298
D.2 Interviews ... 307
D.2.1 List of the stakeholders interviewed ... 307
D.2.2 Interview excerpts... 307
.
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Acronyms and abbreviations
AMWAP Analytical method of the waste allocation process CFWM Cantonal fund for waste management
CHF Swiss franc
CO2 eq Equivalent carbon dioxide
DWM Determinant of waste movements EEA European Environment Agency e.g. Exempli gratia
EWM Effects of waste movements
i.e Id est
GHG Greenhouse gas GWh Gigawatt hours m3 Cubic metres
MFA Material flow analysis MWh Megawatt hours
MWhel Megawatt hours of electricity MWhth Megawatt hours of heat
Mt Megatonnes
OECD Organisation for Economic Co-operation and Development SWOT Strengths, Weaknesses, Opportunities and Threats
t tonne
TWh Terawatt hours TrCo Transfer coefficient WAP Waste allocation process WM Waste management
y Year
1
Chapter 1
Overall introduction
.
3
1.1 Issues, environment and method
1.1.1 From waste generation to waste treatment
Waste is an inevitable outcome of economic activity and physical production (Daly and Farley, 2010; Price and Joseph, 2000). The production of waste constitutes a normal function of all living organisms (Kenneth et al., 2005). However, humans generate additional waste by the supply and consumption of products and services (Baumgärtner and Arons, 2003;
Georgescu-Roegen, 2006).
The Industrial Revolution created the technological basis for the scale-up of anthropogenic production and consumption. Thus, the emergence of consumerism since the Industrial Revolution (Vries, 2008) was accompanied by material abundance never known before (Galbraith, 1958; McLaughlin, 1993; Potter, 1954). This system generated, in turn, growing quantities of waste. Currently, the worldwide waste generation - also called “solid waste”- amounts to 1.24 to 12 billion tonnes per year1 (Chalmin and Gaillochet, 2009;
Hoornweg and Bhada-Tata, 2012; OECD, 2011; UNEP, 2015; UN-HABITAT, 2010). The growing global population, increasing wealth and standard of living, especially that of the middle class in developing countries (Kharas, 2010), and urbanisation (Taylor, 2012) will raise the extraction and use of natural resources (Dobbs et al., 2011; OECD, 2008a) in a business as usual situation. This will increase the production of waste even further (Hoornweg et al., 2013; Hoornweg and Bhada-Tata, 2012). Moreover, technological progress led to the creation of synthetic, new types of metals (Bihouix and Guillebon, 2010) and many further materials. The creation of new industrial products since the 1940s has provoked the generation of toxic and non- biodegradable wastes, which are hazardous to the health and welfare of society (Nemerow, 2007). As a consequence of its quantity and harmful quality, waste has become a nuisance for human health and the environment, and a negative externality from an economic perspective. This necessitates the
1 The factor 10 between these values is explained by the types and sources of wastes accounted by the different methods of calculation used, e.g., the inclusion or the exclusion of mining waste can have a significant impact on the results obtained.
4
development of waste management techniques and practices for their safe disposal.
Many historians (Barata, 2002; Burn et al., 2011; Winiwarter, 2002) have observed diverse traces of waste management activities in different civilisations throughout the course of history. Waste management became a public issue in urban areas only at the end of the 19th century. For example, American cities recognised the garbage as a nuisance for human health and the environment and as an aesthetic problematic (Vaughn, 2011). This recognition coincided with the emergence of the first incinerators in the United States and England (Gandy, 1994; Vaughn, 2011) as waste treatment operations. Since then, the contemporary end-of-pipe waste treatment operations were developed to avoid the release and/or to remove the contaminants that adversely impact water, air and land (Nemerow, 2007). Furthermore, with increasing scarcity of natural resources waste is gradually recognised as a potential resource (Pinjing et al., 2013). This resulted in the development of alternative waste treatment operations aiming resource conservation.
Therefore, various waste treatment operations for the purposes of human health protection, environmental protection and resource conservation co-exist together today.
The international nomenclature (Basel Convention, 2005; European Parliament, 2008; Eurostat, 2010; OECD, 2008b) divide waste treatment operations into two categories: recovery operations and the disposal operations. Recovery operations include all the treatment operations, leading to a substitution of natural resources in accordance with the European jurisprudence (Sander et al., 2004). Among the recovery operations, the two following sub-categories are distinguished (Cossu, 2009a; Massarutto, 2015), i.e. energy recovery operations, e.g., the incineration with energy recovery and the material recovery operations, such as recycling or composting. The disposal operations include those not leading to the substitution of natural resources (Sander et al., 2004). They currently form the main waste treatment operation worldwide (Chalmin and Gaillochet, 2009; Hoornweg and Bhada- Tata, 2012; UNEP, 2015). However, the energy recovery and material recovery operations have become more important since the last decades of the twentieth century. Their respective development led to their competition, causing a competitive use of waste.
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1.1.2 The competitive use of waste between waste recovery operations
In the late 20th century, Miquel (1999) and the Organisation for Economic Co-operation and Development (OECD, 1995) underlined the concurrence of energy recovery and material recovery operations for household waste.
Miquel (1999) raised the concern about the incineration of an increased share of the available waste at the expense of recycling :
“It is important to measure the disadvantages that there are, to juxtapose these two types of recovery that if they are complementary, can also become contradictory, because there may actually be "cannibalisation" of a technique by another. The development of a technical, i.e., incineration [waste-to-energy], prevents, by spiralling motion, any development of the other, i.e., the material recovery.”2
It was expected that this trend would lead to a conflict of use3 for waste recovery. Some authors raised this issue already some ten years ago (Balet, 2008; Koller, 2009)4 and the phenomenon continues to be observed today, sometimes being referred to as (Corvellec et al., 2013; Massarutto, 2015) or
“vacuum cleaner effect” (Gutberlet, 2013). Therefore, different stakeholders argue that the energy recovery sectors are appropriating waste to the detriment of the recycling sectors (European Commission, 2013; Gutberlet, 2013; Jofra Sora and Puig Ventosa, 2013; PIPAME, 2012; Potočnik, 2012).
In Europe, this fear comes from the overcapacity of incineration plants in some regions (Alwast and Birnstengel, 2008; ETC/SCP, 2014; Jofra Sora and Puig Ventosa, 2013; NABU, 2009; OECD, 2014). At the beginning of the 21st century, the European Environment Agency (EEA, 2007) argued that there was no evidence for barriers to the development of recycling by waste incineration
2 “Il convient de mesurer les inconvénients qu'il y a, à juxtaposer ces deux types de valorisation qui si elles sont complémentaires, peuvent aussi devenir contradictoires, car il peut y avoir en réalité
“cannibalisation” d'une technique par une autre. Le développement d'une technique -l'incinération- empêche, par un mouvement en spirale, tout développement de l'autre -la valorisation matière” (Miquel, 1999).
3 The term conflict of use designs a declared opposition between two groups of agents with competing interests at a specific point in time in the use of property with an environmental or territorial dimension (Jeanneaux, 2006).
4 They use the term “cannibalisation” when referring to the increased role of incineration in waste management.
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with energy recovery. However, it currently recognises that “overcapacity in incineration plants in some European countries makes it harder to shift waste management up the waste hierarchy” towards more recycling (EEA, 2013, p.
91). This overcapacity hinders the recycling of household waste (ETC/SCP, 2014; Jofra Sora and Puig Ventosa, 2013), plastic waste (Potočnik, 2012) and waste wood (PIPAME, 2012). It also increases the incentives to incinerate recyclables with a high calorific value, as highlighted by the OECD (2014). For example, the overcapacity of incineration plants in Germany caused a price drop of waste treatment. This acted as entry barrier for the supply of waste to the recycling sector and consistently caused a wave of bankruptcies in the medium-sized recycling industry (Wilts, 2012). Moreover, a study on the socio- political acceptance of new waste facilities in the Netherlands underlines that the “overcapacity of incineration already acquires so much waste that recycling initiatives become frustrated” (Wolsink, 2010, p. 308).
In the United States, the competitive use of waste among treatment operations does not, however, lead to a dysfunctional cohabitation. The presence of incineration plants in the American localities does not limit or reduce recycling rates, due to the recycling policies of American states and proactive waste recycling policies put in place by American municipalities (Brettler Berenyi, 2009, 2008; Kiser, 2003; Psomopoulos et al., 2009). An interstate comparison demonstrates that the recycling rates of the communities with a waste-to-energy facility are higher or closely follow the state average rates in most cases, as underlined by Brettler Berenyi (2014). For the author, state waste policies and programmes represent the key factors influencing the local recycling activities and rates and not the presence of a waste-to-energy facility in a community.
These two contradictory realities described before constitute the starting point of the present doctoral thesis in environmental sciences. Therefore, this thesis will focus on the phenomenon of waste allocation among waste treatment operations. However, one step back must be taken before studying this phenomenon. Thus, it is necessary to address beforehand the environment in which it intervenes, i.e., the waste management system, and the existing methods and tools to analyse it.
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1.1.3 The environment of the waste allocation: Waste management system
The collection, transfer, sorting/pre-treatment and treatment constitute the logistical operations of waste management . The understanding of these waste management operations in conjunction leads to the definition of waste management as a system (de Rosnay, 1977). The system is a set of interacting units or elements that form an integrated whole intended to perform some function (Clark, 1978; Skyttner, 2005). It has a structure, i.e., a set of propositions, relationships and locations of elements and subassemblies, with a specific state at a precise given time that can be modelled (Baud et al., 2008;
Beguin, 1998). In regard to other systems, the waste management system constitutes a system of systems according to Chang et al. (2011), a sub-system of the industrial system for Biel (2011) and a coupled human-environmental system for Meylan et al. (2013). As with all systems, the waste management system has its own purposes: (1) the protection of mankind and environment, (2) the conservation of resources and (3) the aftercare-free waste management (Baccini and Brunner, 2012). Moreover, it shares the same characteristics as every other system defined by de Rosnay (1977): opening, dynamism and complexity. These three features are explained below.
First, the waste management system is by nature open to other systems. It thus exchanges material, substance and energy with other anthropogenic and natural systems (Baccini and Brunner, 2012). First of all, it receives substance and objects from the production and consumption systems, i.e, the “primary waste” (Eurostat, 2010). Thus, it constitutes one of the metabolic processes, denominated “excretion”, located at the end of the social metabolism in which societies dispose of their waste (Gonzalez de Molina and Toledo, 2014). The waste management activities also lead to the transfer of materials and energy, i.e., heat, in the natural system as in the case of the waste incineration. Then, the waste management system receives material and energy flows for enabling safe and efficient treatment of waste, as for the waste incineration (Brunner and Rechberger, 2015; Dalager and Reimann, 2011) from the production system. It also provides energy and secondary resources to economic systems through energy and recovery operations (Brunner and Rechberger, 2015;
Dyckhoff et al., 2013; Pinjing et al., 2013). Lastly, this opening enables waste exchanges among waste management systems (Fischer et al., 2012; Kagawa et
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al., 2007; Ley et al., 2002; Mazzanti and Zoboli, 2013; McCarthy, 2007). This characteristic thus constitutes an intrinsic quality of a waste management system and accentuates its dynamism and complexity.
The second characteristic of a waste management system is its dynamism, i.e, its constant in evolution or change. The waste management system has the characteristics of a complex adaptive system (Clayton and Radcliffe, 1996). It thus interacts with its environment and it changes in response to the changes in its environment. Moreover, it reflects the coevolution of the human and natural systems over time (Meylan et al., 2013), due to its position downstream of the production and consumption systems. The constant change of society that leads to a change in the nature of waste (O’Lear, 2010) constitutes the main driver of this dynamism. For example, the diffusion of information and communication technologies over the past decades has generated new types of waste, electronic waste (CERTU, 2003). Its generation leads to the creation of new waste management systems, as in Switzerland (Sinha-Khetriwal et al., 2005), and new waste treatment industries (Grossman, 2007). The nature of waste also changes with the increasing commodification of waste (Knoepfel et al., 2010). This commodification is observable through the growth of waste trading volumes and values worldwide (Bernard et al., 2014). It is also observable from the market share increase of secondary resources in resource trading (Glachant et al., 2012).
Evolution of the waste management practices constitutes another driver of its dynamism. Thus, the new organisational constraints have changed the configuration of the waste management systems over time. These constraints are, for example, the introduction of stricter environmental regulation, regulation frameworks for specific waste streams, waste recovery and landfill targets or new funding arrangements (Holzinger et al., 2011; Jörgens et al., 2014; Lupton, 2011). The waste management systems have thus evolved from a mono-treatment management towards a multi-treatment management, operating in parallel (Defeuilley, 1996). However, different constraints exist, slowing down this dynamism. These constraints lead to a relative inertia of the system. These constraints come from long-term planning horizons of waste management activities (Seyring et al., 2013), public opposition against waste infrastructure, e.g., NIMBY syndromes (NIMBY stands for “not in my backyard”), or political indecision, e.g., NIMO syndromes (NIMO stands for
“not in my office time” (Cossu, 2009a; McDougall and White, 2001). For
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example, Corvellec et al. (2013) identify four mechanisms of lock-in (i.e., institutional, technical, cultural and material) acting on a Swedish municipality which is consolidating waste incineration. They act as barriers slowing down the emergence of more sustainable urban infrastructure as an alternative to incineration plants. This dynamism has affected the waste management. It thus becomes more complex and sophisticated (Tchobanoglous and Kreith, 2002).
Third, the waste management system constitutes a complex entity. It is measured by the increasing number of links between the system components and the stakeholders associated to waste management (Ghiani et al., 2014;
Seadon, 2010). It is also observable from the segmentation of the waste management system into several sub-systems (UNEP, 2009). The complexity of the waste management system is mainly the consequence of its open nature and the results of its dynamism over time. The three characteristics of waste management systems cause their diversification leading thus to their heterogeneity.
Hoornweg and Bhada-Tata (2012) and Adedipe et al. (2005) note significant differences between systems from developing and industrialised countries regarding waste management practices, waste composition and waste generation. Moreover, Christensen (2011a) underlines the presence of different waste management practices among countries, due to differences in waste composition, management costs, availability of land, possibilities of recovery, political focuses and national preferences. Moreover, the heterogeneity of waste management systems is the results of its three characteristics (see above) which are related to the local nature of the waste generation and its management. Here, the term “local” refers to a geographical area covering the lowest tier of administration within a given state, e.g., a city or a municipality. First, the quantities and the composition of generated wastes depend on several regional and local factors (Bandara et al., 2007;
Chowdhury, 2009; Clement, 2007; Diaz et al., 2005) without omitting macro- determinants (Hoornweg and Bhada-Tata, 2012; IPCC et al., 2007; UNEP, 2013). And second, the techniques applied in waste management depend on existing local conditions (Strange, 2002). It should be considered here that the local governing bodies have a high level of autonomy on the concrete waste management decisions (Christensen, 2011b; OECD, 2014) and waste management governance (Lindqvist, 2013).
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The heterogeneity of waste management systems leads to strong differences in their structure. It reflects these structures that waste allocation between treatment operations occurs. Therefore, the study of this phenomenon in various situations necessitates the development of a general analytical framework. Although any case study has a limited scope, this approach constitutes a good starting point to study the phenomenon of waste allocation in the framework of an exploratory study (Selltiz et al., 1977). The next step is to identify the relevant method for studying the waste management system.
1.1.4 Methods and tools for the study of the phenomenon of waste allocation
The scientific literature contains various reviews on a plethora of methods, models or tools dedicated to the analysis, assessment and/or decision-making of waste management systems and its compounds (Achillas et al., 2013;
Allesch and Brunner, 2014; Chang et al., 2011; Ghiani et al., 2014; Karmperis et al., 2013; Morrissey and Browne, 2004; Pires et al., 2011; Soltani et al., 2015;
Zurbrügg et al., 2014). They address cost-benefit analysis, the forecasting model, simulation models, optimisation models, material flow analysis, life- cycle assessment, risk assessment, environmental impact assessment, strategic environmental assessment, exergy analysis and multi-criteria-decision- making. As important further method, input-output analysis should be added (Nakamura and Kondo, 2009).
Material flow analysis (MFA) represents the relevant methodological approach to study the movements of waste flows in a waste management system. MFA belongs to a family of methods applied to study material systems (Moll and Fernia, 2005; OECD, 2008a). These methods provide a comprehensive overview on the life cycle of materials by a meso-level analysis.
Thus, MFA constitutes a systematic evaluation method of flows and stocks of material (and energy) in a system defined in space and time (Baccini and Brunner, 2012; Brunner and Rechberger, 2004). It aims to map the volumes of material (and energy) flows, the interconnections between processes, stocks and flows within a system and the exchanges of flows with the external systems (Hauschild and Barlaz, 2011). It provides different indicators expressed in tonnes of materials or in joules (Loiseau et al., 2012). This method is suitable to study the urban metabolism and regional metabolism (Gonzalez
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de Molina and Toledo, 2014; Kennedy et al., 2014) and to establish material and energy balances (Loiseau et al., 2012). It forms the most popular method to study industrial metabolism at different spatial scales (Kronenberg, 2007).
MFA has several advantages for studying waste management systems.
First, it provides an understanding of how waste management systems function (Allesch and Brunner, 2015) and it reveals any deficiencies in the system (Christensen, 2011b). Second, the body of research conducted in the past has led to a vast database which is useful when implementing MFA (Eurostat, 2012; Fritsche, 2013; OECD, 2008c). Third, MFA allows to observe systems at different time scales (from a short to long time periods; Chang et al., 2011). Two approaches are applied: a stationary or quasi-stationary approach (Binder et al., 2004; Faist Emmenegger and Frischknecht, 2003) and a dynamic approach (Hu, 2010; Müller et al., 2004; Suomalainen, 2012; Taverna et al., 2007; Werner et al., 2010). The use of MFA through a dynamic approach provides an understanding of the variability in the structure of the waste management system over time and of possible changes in trends (Sevigné-Itoiz et al., 2015). This ability is important, due to the dynamism of the waste management systems over time. Fourth, MFA can be used in combination with other theoretical and methodological approaches. Binder (2007) lists several studies, using MFA with other research methods from economy and the social sciences, e.g., general equilibrium models, micro and macroeconomic models, surveys and psychological experiments. These examples show the ability of MFA to integrate an interdisciplinary research perspective. However, Binder (2007) also underlines the difficulty to integrate MFA results in decision- making at the regional scale, because it only provides a simple description of a material system. Moreover, MFA does not include enough qualitative information for the analysis of waste when waste forms a “good”, i.e., economic entities with a positive or negative value (Allesch and Brunner, 2015). As a consequence, MFA offers only limited explanation of the functioning of waste management systems. Without the inclusion of other methods, MFA is bound by mapping the circulation of waste flows in a system. Thus, it only has a descriptive power to answer “how” and not an explanatory power to answer “why”.
Even if MFA constitutes the relevant methodological approach to study waste allocation among recovery and disposal operations, the present thesis must overcome the limit of MFA just presented. Therefore, the intended
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general analytical framework on waste allocation among recovery and disposal operations must have both descriptive power and explanatory power.
1.2 Objectives and structure of the thesis
1.2.1 Objectives and scopes
This thesis builds on the aspects discussed above to address the phenomenon of waste allocation among treatment operations in a waste management system and to bring new knowledge on this phenomenon.
First of all, this thesis aims to develop new intuitions and to clarify the concepts linked to the waste allocation among treatment operations through a case study on the waste wood management in Switzerland. The case study approach is an adequate choice for an exploratory study, allowing to trace new and neglected phenomena (Roy, 2003), to provoke new intuitions and ideas (Selltiz et al., 1977) and to identify new solutions. In addition, the case study approach remains a relevant methodological basis to study complex phenomena within their contexts, which enables answering “how” and “why”
questions and building theory (Baxter and Jack, 2008). Within this thesis, the case study serves these purposes.
Thereafter, the results of this case study and those of an additional literature review, will be subjected to an inductive process to conceptualise a framework on the waste allocation process. It will lead to propose the analytical method of the waste allocation process, as a new methodological tool for assessment of waste management systems. The novelty of this method comes from the interdisciplinary perspective used to define this allocation process. This will allow to provide an innovative approach for researchers and practitioners to study waste management systems. However, this method does not aim at the optimisation of the waste allocation between waste treatment operations. This objective is already provided by various mathematical modelling techniques (Dai et al., 2011; Ghiani et al., 2014; Guo and Huang, 2010; Srivastava and Nema, 2012; Tan et al., 2014; Wang et al., 2008).
The implementation of this method in a first empirical study offered new insights, leading to an additional and unanticipated field of research. It
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provided the basis for the final part of this thesis which consists of a new method for evaluating waste policy – also called “waste management policy”–
and its related policy instruments. The novelty of this evaluation method consists of combining the concept of “policy resources” – also called “state resources”– from political sciences with material system analysis. Thus, this method focuses on joint analysis of the evolution of the material system of waste management and “policy/state resources” mobilised or regulated by public actors over time to measure the effects of waste policy and/or policy instruments. This combination of different concepts and methods constitutes another originality introduced by this thesis.
1.2.2 Interdisciplinary perspective
This thesis follows an interdisciplinary perspective to grasp the waste allocation phenomenon. It constitutes “a process of answering a question, solving a problem, or addressing a topic that is too broad or complex to be dealt with adequately by a single discipline or profession and drawing on disciplinary perspectives and integrating their insights by producing a more comprehensive understanding” (Klein, and Newell, 1997, pp. 393–394). Thus, this thesis rejects the mono-disciplinary perspective due to the complexity of environmental issues, including waste-related issues. In view of the objectives of the thesis described previously, the interdisciplinary perspective followed here relies on a “pragmatic approach that focuses on research, methodological borrowing, and practical problems” (Repko, 2008, p. 17). Moreover, the convergence of scientific disciplines provided by this perspective aims to serve the problem (Rege Colet, 2002). Therefore, this thesis will borrow from various disciplines their conceptual and theoretical concepts.
1.2.3 Structure of the thesis
This thesis contains three sections, as shown Figure 1.1. Section I provides an empirical study on waste wood management in Switzerland. This case study will compare waste wood allocation in Switzerland between current and prospective waste treatment operations under various scenarios to address different issues, i.e. the coherence of the waste wood management and the energy and climate impacts of waste wood recovery in Switzerland. The previous work by the author on the energy recovery from waste wood in the
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canton of Geneva (Bergeron, 2010) explains the choice of this topic. The presence of possible tensions between the goals of wood resource policy and energy policy also justifies this choice. Most importantly, the Swiss government acknowledges that “the promotion of the energetic use of wood by energy policy is not coordinated with the objective of the resource-efficient use of wood (cascade use)” (Swiss Confederation, 2008, p. 27). In addition, it recognises that the increase of renewable energy demand, boosts that of biodegradable wastes, “giving rise to a real battle over waste” (Schenk, 2011, p.
21).
The body of knowledge acquired in this case study and a complementary scientific literature review provided the necessary insight to realise a selection of the essential elements of the phenomenon of waste allocation. An inductive process5 enables this construction-section process. Therefore, Section II formalises these insights through the development of the “analytical method of the waste allocation process”. It constitutes a new methodological tool for the analysis of waste management systems. An illustrative case study follows the description of this method.
As mentioned at the end of section 1.2.1, the empirical implementation of this method has allowed to explore a new field of research. Thus, Section III presents a new method for waste policy assessment. This hybrid method relies on joint analysis of the evolution of the material system of waste management and “policy/state resources” mobilised or regulated by public actors. This method serves to evaluate the waste policy of the canton of Geneva for household wastes.
Figure 1.1 describes the structure of this thesis by publications. It thus contains ten chapters. The main chapters are the articles published in various peer-reviewed scientific journals. Before presenting the five abstracts of the articles, each chapter is presented individually to put it into context and to link the different chapters and sections.
5 In an inductive approach, the observed empirical facts serve to constitute a more general rule (Selltiz et al., 1977).
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Figure 1.1: Presentation of the different sections and chapters of the thesis.
Chapter 2 in Section I evaluates the coherence of waste wood management in Switzerland relative to the different objectives of Swiss policies and strategies. The assessment focuses on the allocation of waste wood between the current and alternative waste treatment operations in Switzerland. It relies both on a quantitative approach and a qualitative approach. To deepen the insights gained in Chapter 2, Chapter 3 assesses the long-term potentials of waste wood for energy production and greenhouse gas emission reductions in Switzerland. Chapter 4 provides the final remarks on Section I. It discusses the lessons learned from this case study for the upcoming study of the phenomenon of waste allocation among treatment operations.
Chapter 5 in Section II constitutes the core of the thesis. It presents the
“analytical method of the waste allocation process”. Thus, this chapter describes the two components of the method: the conceptual framework with a descriptive model and an explanatory model, and the analytical approach. The latter consists of a step-by-step approach aiming at the empirical implementation of the conceptual framework. This chapter finishes by the presentation of an illustrative case study. It aims to analyse the household
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allocation of the waste management system in the canton of Geneva over the period 2002–2013. Chapter 6 provides the final remarks of Section II. It discusses the forces and limits of the analytical method by a critical analysis under an epistemological perspective.
Chapter 7 and Chapter 8 in Section III provide the results of additional insights gained by the empirical implementation of the analytical method presented in Chapter 5. Thus, Chapter 7 presents a first version of a new evaluation method and a first application in a case study of the household waste management system in Geneva. Chapter 8 provides a more detailed formulation of the evaluation method in the framework of a more global assessment. The latter relies on this new method with a SWOT analysis. The assessment aims to evaluate the waste policies in the canton of Geneva and to improve household waste sorting. Chapter 9 provides the final remarks of Section III. It discusses on the strengths and limits of the proposed evaluation method under an epistemological perspective.
Finally, Chapter 10 presents the main findings of this thesis. It also recapitulates the principal recommendations for decision-makers and policymakers. It ends with a discussion about the limits of the research to suggest further research.
Chapter 2: Waste wood recovery by thermal treatment with energy recovery or by recycling allows to substitute and conserve primary resources.
The Swiss government acknowledges the potential presence of tensions between policies that simultaneously encourage the cascade use of wood, recycling or the energy recovery by thermal treatment of waste wood. The aim of the present research is to assess the coherence of waste wood management in Switzerland by means of a quantitative and qualitative approach. First, the use of the methodology of material flow analysis allows modelling of wood resources and waste wood metabolism over one century. The simulation results for various scenarios of waste wood management show that the additional impacts of immediate thermal treatment are less significant for the reduction of CO2 eq emissions but more significant for the energy production than its cascade treatments on Swiss territory. Second, a documentary analysis examines the determinants of the current waste wood treatment prevailing in Switzerland. The strong presence of the thermal treatment sector on Swiss territory, the export of almost half of the waste wood generated and the sub-
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exploitation of the Swiss forest act as barriers or drivers that result in a crowding-out effect, where no amount of waste wood is available for recycling in Switzerland. The comparison of the results of the two approaches leads to the conclusion that the current waste wood management is coherent in relation to the various goals of the Swiss federal policies, but the waste wood potential for energy production is not fully exploited. The recommendations on the waste wood management and the possibilities to use the model for other case studies are given in the conclusion.
Chapter 3: Waste wood represents as much a waste to dispose of as a secondary resource to exploit. Various studies have assessed the energy potential and/or climate impact of energy recovery from waste wood. This paper aims to assess the long-term potential of waste wood for energy production and greenhouse gas (GHG) emissions reduction in Switzerland.
Material flow analysis (MFA) is applied for modelling the metabolism of wood and waste wood in the Swiss anthroposphere over one century. The energy and climate impacts are estimated for 32 scenarios which assume different forest harvesting variants and waste wood treatment options. The scenario analysis shows that waste wood treatment options are more beneficial in the long term in terms of energy production (by energy recovery from waste wood) and of GHG emission reduction than the increase in the quantities of waste wood generated in the future caused by the advocated strategies of increased forest harvesting. By using the Maximin criterion, the long-term optimal additional potential for energy recovery from waste wood is estimated at 2,110 GWh/year of useful energy, which offers a reduction of 364 tonnes of CO2 equivalents per year. As prerequisites, the nominal installed capacity of the waste wood boilers needs to be raised and their efficiency and as well as those of incineration plants need to be increased. In addition, the sustainable potential of Swiss forests must be fully exploited. This study identifies various recommendations for the optimal exploitation of energy recovery from waste wood.
Chapter 5: Waste is not a rejected item to dispose anymore but increasingly a secondary resource to exploit, influencing waste allocation among recovery and disposal operations in waste management (WM) systems. While material system analysis methodologies allow to map the WM system, they fail to explain its operation. The aim of this research is to propose a new method for the assessment of the WM system, the “analytical method of the waste
