A Bi-Level Model for a Closed-Loop Agricultural Supply Chain Considering Biogas and Compost

Abstract

In today's competitive marketplace, to increase customer satisfaction and profitability, supply chain management has become more prominent. Therefore, thorough planning and designing the supply chain by seeing all levels and units are essential to growing the efficiency of the entire supply chain. In the present study, an eight-echelon network is designed for a closed-loop agricultural supply chain. These eight echelons are consist of suppliers, farms, distribution centers (DCs), customers, recycling depots, biogas centers, compost production centers, and biogas applicants. To design the agricultural logistics network, a bi-level programming mathematical model is presented that optimizes the network costs and profits. Also, some meta-heuristics and hybrid meta-heuristics are applied for solving the formulated problem. It should be noted that bi-level programming problems are part of the NP-hard class and due to the computational complexity of the problems, the meta-heuristic algorithms are utilized. Finally, various comparisons and analyses are performed to evaluate the model's performance and the capabilities of the solution methods.