Circularity potential identification for new bio-materials using material flow analysis.

Transitioning to a Circular Economy (CE) in the bio-based materials sector is essential for achieving sustainability and reducing environmental impacts. This study presents a comprehensive circularity assessment across three novel bio-based value chains: multifunctional rubber panels, bioplastic bottle closures, and wood composite bearings. Utilizing an integrated methodological approach that combines Material Flow Analysis (MFA) with advanced circularity indicators and Bill of Materials (BoM), the research quantifies resource efficiency, waste reduction potential, and closed-loop material flows within these systems. The analysis reveals substantial differences in circularity outcomes among these three value chains. Multifunctional rubber panels demonstrate a high circularity potential, with recycled content constituting up to 68.1 % of the total material input. However, opportunities for improvement remain in addressing the variability in secondary rubber quality and optimizing lignin recovery processes to enhance circularity. Bioplastic bottle closures exhibit the highest renewable input utilization, reaching up to 85 %, yet still present opportunities for improvement, particularly in the scalability of waste recovery systems and addressing regulatory constraints on food-grade recycled materials. Wood composite bearings effectively utilize forest residues and natural fibers, thereby reducing their dependency on non-renewable inputs, but are currently facing technical development needs in component disassembly and recycling strategies, presenting pathways for future optimization of material recirculation. To address these challenges, the study proposes strategic interventions tailored to each value chain, including the development of advanced recycling technologies, enhancement of eco-design for disassembly and recyclability, and fostering stakeholder collaboration to close material loops. By advancing the application of MFA combined with BoM in evaluating circularity metrics, this research provides a robust analytical framework that transcends conventional qualitative assessments. The value chain-specific evaluation contributes to operationalizing CE principles within bio-based production systems and offers actionable insights for policymakers, industry leaders, and researchers. These findings support strategic decision-making aimed at aligning industrial practices with the European Green Deal and global sustainability targets.