A Systems Engineering Framework for the Optimization of Circular Economy Supply Chains

The current linear “take-make-waste-extractive” model leads to the depletion of natural resources and environmental degradation. Circular Economy (CE) aims to address these impacts by building supply chains that are restorative, regenerative, and environmentally benign. This can be achieved through the re-utilization of products and materials, the extensive usage of renewable energy sources, and ultimately by closing any open material loops. Such a transition towards environmental, economic and social advancements requires analytical tools for quantitative evaluation of the alternative pathways. We present the foundations of a systems engineering framework and quantitative decision-making tools for the modeling and trade-off optimization of interconnected supply chain networks to achieve a CE.  The framework combines data analytics and mixed-integer modelling & optimization methods to establish (i) the interconnections between different stages of the circular supply chain, (ii) the potentially competing interests amongst various stakeholders, and (iii) policy, regulation and societal issues. A multi-objective optimization strategy is followed for the analysis of the trade-offs empowered by the introduction of composite metrics for CE that include waste, energy and resource use minimization, as means to facilitate decision making and compare alternative process, materials, resources and technological options. A representative case study for the supply chain of coffee will be discussed, illustrating the steps and the applicability of the framework.