Product circularity assessment: a methodology to guide Manufacturing towards more circular products

Growing resources’ depletion and value dissipation caused by current production-consumption models need attention. Industry holds a role of responsibility in the way in which inputs are transformed into economically valuable outputs, and how products and resources are managed along their lifecycle to ensure value maximization through their retention. As a result, it is also responsible for economic losses for businesses and for the negative burden on social and natural systems. This research investigates the challenges faced by the Circular Economy in being adopted as a new development model for manufacturing systems. Particularly, this thesis tackles the issue of the adoption of Circular Economy practices and principles at product system level. The objectives are to provide companies with a methodology to realize products that are more circular, starting from the assessment of the current products’ performance of circularity at operational level (resources consumption) and supporting them to define actions for improvement. The work started with a review of the existing methods and tools for the evaluation of products’ circularity performance and their criticalities highlighted the need for further research. Therefore, a theoretical framework (Product Circularity Assessment Methodology) to define measures of circularity at product level was proposed. The circularity performance of a product is strongly related with the ability of adopting CE theoretical notions such as CE principles and integrating CE practices within the current business activities. The analysis of existing knowledge brought to the identification of CE principles and practices from related fields (e.g. industrial ecology and symbiosis, sustainable development, natural capital, biomimicry, green and blue economy and performance economy). From this analysis, calculations (CPA Metric) were designed to capture the circularity performance of a generic product based on the characterization and path of the resource flows (materials and energy) within the product system of reference. The final output is the product circularity indicator (CPI), resulting from aggregated indexes of materials and energy circularity along the product life cycle phases. To test the methodology, experts were interviewed and principles and practices refined. The calculations were validated through several prototypes and finally applied to two industrial cases, respectively in the transport and medical sectors. In order to support the manufacturers in improving the current circularity performance of their products, an improvement methodology (Circular Economy Transition Methodology) was develop to provide structured process for the identification, analysis and prioritisation of interventions. The levers to overcome the obstacles that currently prevent the occurrence of circularity are extrapolated from the review of the literature and proposed, after theoretical validation with experts in the field, as standard tactics for improving the circularity of products. The improvement methdodology was applied to the industrial case in the transport sector. The contribution to knowledge of this work is enclosed in bridging the gap between theoretical concepts for Circular Economy and industrial activities by developing a methodology to assess the performance of circularity of products and providing tactics and standardised processes for improvement. From a practical viewpoint, the research provides a structured and systematic approach for manufacturers to undertake the journey towards more circular products by improving the management of resource flows at product system level.

Questa ricerca indaga le sfide che l’Economia Circolare deve affrontare come nuovo modello di sviluppo per i sistemi manifatturieri, e in particolare si focalizza sul problema dell'adozione di pratiche e principi circolari a livello di sistemi di prodotto. Gli obiettivi sono fornire alle aziende supporto per la realizzazione di prodotti più circolari a partire dalla valutazione del consumo e della gestione di risorse lungo il loro ciclo di vita e aiutarle nella definizione di azioni di miglioramento delle prestazioni attuali. Pertanto, questo lavoro propone uno strumento (Product Circularity Assessment and Metric) che traduce concetti teorici di circolarità in misure reali attraverso lo sviluppo di un indicatore (Product Circularity Indicator) aggregato di indici di circolarità di materiali e di energia lungo il ciclo di vita del prodotto. Inoltre una metodologia di miglioramento delle attuali prestazioni di circolarità (Circular Economy Transition Methodology) è stata sviluppata per fornire processi strutturati per l'identificazione, l'analisi e la definizione delle priorità di intervento. Attuatori di flussi circolari di risorse (Circular Economy Levers) sono stati identificati dalla letteratura e integrati nella metodologia in quanto suggeriscono azioni per modificare le pratiche operative e manageriali in ottica circolare.