Municipal Solid Waste (MSW) management plays a key role in achieving circular economy and climate neutrality goals across the European Union. Within this framework, collection is not just a logistical operation, but a strategic element for improving material recovery, and reducing environmental impacts. However, collection is still often treated as a routine service, with limited integration into planning and policy frameworks. This doctoral research addresses this gap by investigating how MSW collection optimisation can enhance system performance, focusing on three dimensions: material capture, operational efficiency, and environmental sustainability. Chapter 1 introduces the regulatory and conceptual background, with a comparative focus on MSW systems in Italy and Spain, particularly in Tuscany and Catalonia. It outlines the research objectives and describes the methodological approach, which combines empirical data, statistical analysis, environmental-economic modelling, and system-based assessment tools-namely, material flow analysis (MFA) and life cycle assessment (LCA). Chapter 2 investigates MSW composition and separate collection (SC) performance in Tuscany, using over 1,100 samples across all fractions, including residual waste. A harmonised classification was adopted to reflect policy-relevant categories (e. g. packaging, textiles, sanitary waste). Biodegradable organics accounted for the largest share (27. 2%), followed by paper/cardboard (21. 3%) and plastics (16. 3%). Over 50% of residual waste consisted of recyclable materials, suggesting room for improvement. Despite a high SC rate (67%), capture inefficiencies persist, particularly for plastics and metals, and impurity levels in light packaging remain high. Door-to-door (DtD) systems outperformed street-bin (SB) models in terms of quality, supporting the adoption of context-specific improvements such as smart containers, PAYT schemes, and targeted communication. Chapter 3 explores the environmental and economic implications of collection logistics. A field campaign in central Tuscany recorded 233 real-world fuel consumption observations across vehicles and configurations. Results showed higher CO₂ emissions than national estimates, ranging from 2. 3 to 3. 7 kg CO₂/km for heavy-duty vehicles. A predictive model was developed to simulate DtD and SB performance under varying urban densities. SB systems proved more efficient in high-density areas, while DtD showed lower emissions in low-density areas. When accounting for SC quality, DtD systems outperformed SB models across all densities in CO₂ terms, though SB remained more cost-effective. The analysis revealed a misalignment between environmental and economic performance, suggesting the need for better incentives (e. g. landfill fees, quality bonuses, and smart technologies to enhance SB quality). Chapter 4 applies an integrated MFA-LCA framework to MSW management in Catalonia, comparing the current system (45% SC rate, 11% DtD coverage) to a high-performance scenario (65% SC, 72% DtD). MFA showed improved recycling (from 37. 7% to 53. 3%) under the high-performance setup, but a high landfilling rate (29. 5%) persisted, mainly due to residues from recycling processes. This underlines the importance of diverting residual and rejected waste to high-efficiency waste-to-energy (WtE) plants and reducing non-recyclable material at source. LCA results confirmed that the high-performance scenario brings substantial environmental benefits, including a 23% reduction in net climate change impacts, primarily driven by increased material recycling. However, greenhouse gas emissions from collection and treatment increased, as did local impacts like particulate matter (+181%) and photochemical ozone formation (+146%), highlighting trade-offs and the need for better logistics, fleet design, and treatment infrastructure. Chapter 5 identifies five key actions: • Promote harmonised, time-structured waste characterisation campaigns to support planning and policy. • Enhance SC systems by focusing on quality of collected materials. • Use empirical data for robust environmental and economic assessments. • Reframe the role of collection as a strategic function in circular economy transitions. • Prioritise WtE and eco-design alongside reuse and recycling to reduce residual waste. By integrating real-world data, modelling, and scenario-based analysis, this thesis reframes waste collection as a central pillar of sustainable MSW governance and provides guidance for both local and national decision-makers
| Date of Award | 21 Nov 2025 |
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| Original language | English |
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| Awarding Institution | |
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| Supervisor | Claudio Lubello (Director) & Laura Talens Peiro (Director) |
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