A digital twin framework for cyber-physical waste stream control systems: towards reverse Logistics 4.0

Background: With socio-economic development, an increase in waste generation is observed. In view of its negative impact on the environment and human health, it is becoming increasingly important to follow the waste hierarchy and perform research on reverse logistics. It is crucial to maximize the efficiency of the separation of the waste mixture into fractions which can be returned to the material cycle in the economy. The separation process is carried out in systems such as waste sorting plants, which are characterized by complexity and variable input waste stream composition. Therefore, research in this field is usually based on simplifying assumptions and static input-output data and limited in scope. There is a lack of studies dedicated to the real-time control of these systems. Methods: We propose a Digital Twin framework for waste sorting systems to address the limitations of solutions available in the literature and to standardize the development of cyber-physical waste stream control systems. The proposed approach includes one of the key technologies of Industry 4.0, so it is in line with the Reverse Logistics 4.0 concept. Results: The main components of the Digital Twin considered were a sensor-based waste stream monitoring system, a physical model of the sorting system, a simulation model and its integration with the physical model. The deployment of a Digital Twin in line with the presented framework is demonstrated using the example of a selected plastic waste sorting plant. Conclusions: Based on the proposed approach, it is possible to include waste stream features (heterogeneity, composition uncertainty and high variability) in logistics decision-making in detail and in real time. The implementation of a Digital Twin can reduce the amount of waste sent to landfill and significantly increase the achieved recovery rates, thus increasing the amount of waste being reused and thereby contributing to the transformation to a circular economy.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).