A sustainable-circular citrus closed-loop supply chain configuration: Pareto-based algorithms

Area of Science:

• Operations Research
• Supply Chain Management
• Environmental Science

Background:

• Sustainable supply chain configuration is an evolving research area, particularly for agricultural products.
• Existing models often lack integration of social and environmental impacts in supply chain network design.
• Citrus supply chains present unique challenges for sustainability and circularity.

Purpose of the Study:

• To develop a novel model for designing sustainable citrus supply chains.
• To integrate production, distribution, inventory, recycling, and location decisions.
• To address the triple bottom lines of sustainability and circularity within a closed-loop framework.

Main Methods:

• A multi-objective Mixed-Integer Linear Programming (MILP) model for a multi-period, multi-echelon citrus supply chain.
• The ε-constraint approach for small-sized problems.
• Strength Pareto Evolutionary Algorithm II (SPEA-II) and Pareto Envelope-based Selection Algorithm II (PESA-II) for larger problems, optimized using Taguchi design.

Main Results:

• The proposed MILP model effectively formulates the sustainable citrus closed-loop supply chain (CLSC) design.
• Numerical results indicate SPEA-II demonstrates superior efficiency compared to PESA-II for solving the optimization problem.
• Sensitivity analyses validate the methodology's applicability through a real-world case study in Mazandaran, Iran.

Conclusions:

• The developed methodology provides a robust framework for designing sustainable and circular citrus supply chains.
• SPEA-II is an effective algorithm for optimizing complex CLSC network designs.
• The integration of sustainability and circularity is crucial for modern agricultural supply chain management.