A nonlinear optimization framework to minimize environmental impact in a three-stage supply chain network

This paper presents three mathematical models for sustainable supply chain management (SSCM). The models share the same constraints and present three different objective functions, one convex and two nonconvex, accounting for different emission behaviors within the supply chain. A solution algorithm is developed to solve the models, integrating gradient projection, active set methods, and convex combination refinements. A specific application to a multi-tier supply chain is examined, aiming to minimize the total environmental impact, measured in terms of emissions from transportation and production activities. The findings underscore the potential of the proposed models and solution method in addressing SSCM challenges while meeting sustainability objectives.