Designing a sustainable closed-loop supply chain network for walnut industry

Abstract

In the history of sustainable development, logistics has been thought of as one of the key factors in the supply chain network. In the meantime, the issue of Closed-loop Supply Chain (CLSC) has received considerable attention as it ensures many diverse industries toward sustainability. But many industries including agricultural section often fail to address and fulfill these requirements. In this study, a new CLSC network is designed for the walnut industry as a part of agricultural crop by conducting a complete review of the past studies. Therefore, a new Mixed Integer Linear Programming (MILP) for the proposed network is developed minimizing the overall costs of the walnut industry. The designed network considers both forward and reverse flow not only to meet the demands of various markets, but also to prepare the returned products for the second use. In order to solve the proposed model, a set of exact, metaheuristics, and hybrid metaheuristics are employed. Finally, the best solutions are obtained by assessing the finest initial answers using Taguchi method. The results notoriously illustrated the excellent consistency between the proposed network and the employed algorithms along with its applicability and efficiency.