A semi-quantitative system dynamics model of circular manufacturing and plastic recovery in Chile

The transition toward a circular plastics economy requires manufacturing companies to improve internal material recovery while managing the complex interactions among production, infrastructure, and operational processes. Although previous research has primarily focused on policy and waste management, limited attention has been given to the dynamic mechanisms influencing material reuse within manufacturing systems. This study addresses this gap by applying a multi-step, participatory system dynamics modeling and scenario analysis approach to identify and evaluate the key factors, feedback mechanisms, and leverage points affecting circular plastic implementation in a Chilean plastic manufacturing company. Data were collected through structured interviews with 18 experts and analyzed using influence mapping, cross-impact structural analysis, causal loop modeling, and qualitative network modeling. Thirteen critical factors were identified and grouped into infrastructure, processes, control, and management dimensions. The results identified recovery plant infrastructure, parameterization of the production cycle, and maintenance deficit as the system's principal leverage points. Five dominant feedback loops revealed how infrastructure capacity, process standardization, material quality, and equipment reliability jointly influence material reuse. Qualitative network modeling of these loops revealed the most effective intervention scenario centers on increasing recovery plant infrastructure and production cycle parameterization while reducing maintenance deficit, thereby strengthening enablers and mitigating barriers to material reuse. These findings demonstrate that circular manufacturing performance emerges from the interaction of infrastructure, process optimization, and maintenance, providing a practical framework to support decision-making and accelerate circular manufacturing in the plastics industry.