The role of Circular Economy in Resource Security

Abstract

The European Union increasingly frames the Circular Economy as a means to advance its Open Strategic Autonomy vision, a shift reflected in policies on the supply security of Critical Raw Materials. Titanium metal is central to this debate given its importance for aviation and defence and the European structural reliance on external suppliers. However, two significant limitations persist in research assessing how circular strategies contribute to its supply security. First, no integrated, system-wide assessment explicitly quantifies the security gains of circular interventions in both material and economic dimensions. Second, while policy narratives link circularity to strategic autonomy, empirical assessments rely on isolated indicators not directed by clearly defined strategic objectives. As a result, the security implications of circular economy strategies for titanium remain insufficiently operationalised.

To address these gaps, the thesis develops an analytical framework and applies it to titanium supply security under a national security discourse. Within this perspective, supply security is defined along two measurable dimensions of strategic autonomy: material self-sufficiency and domestic value creation, which guide the selection of indicators used to evaluate circular interventions. The framework is applied by reconstructing the current titanium supply chain in the European Union through Material Flow Analysis, identifying key stocks, flows, and external dependencies. Two scenarios in the aviation sector up to 2040—enhanced domestic recycling and aircraft lifetime extension—are then modelled using dynamic MFA to assess material effects and Multi-Regional Input–Output analysis to evaluate impacts on domestic value creation.

The baseline analysis shows that the current titanium configuration in the European Union is characterised by two structural vulnerabilities: near-total import reliance at the midstream level and substantial losses through pre-consumer scrap generation during component manufacturing. Enhanced domestic recycling delivers the strongest improvements in both dimensions of supply security, increasing material self-sufficiency by approximately 35% and generating an estimated €43.7 million in domestic value added and around 500 jobs. However, these gains are largely driven by retention and reprocessing of pre-consumer scrap rather than end-of-life recovery. Even under existing remelting capacity, secondary feedstock would be depleted within roughly a decade, limiting its structural contribution. Moreover, more than half of pre-consumer scrap remains bound to buyback agreements with the United States, constraining strategic autonomy. Aircraft lifetime extension performs more modestly in static comparisons, delivering roughly half the economic gains of recycling. Yet by slowing inflow requirements, it acts as a demand-side buffer, suggesting that strengthening maintenance, repair and overhaul capabilities represents a relevant complement to recycling efforts.

Overall, the thesis shows that circular economy strategies can support strategic autonomy objectives, but their effectiveness depends on a holistic, system-wide, and dynamic perspective on the supply chain. Conceptually, it situates circular interventions within a resource security framework bridging industrial ecology and international relations. Methodologically, it introduces a hybrid approach combining dynamic Material Flow Analysis with Multi-Regional Input–Output modelling to assess material flows and economic interdependencies simultaneously. Empirically, the titanium case illustrates both the opportunities and limits of circular interventions, informing policy and industry strategies to strengthen domestic control and industrial capacity.


Github: https://github.com/SGhirlandi/Ghirlandi_2026---Thesis---Supplementary
Zenodo: https://doi.org/10.5281/zenodo.18055825