Mixed Fleet Vehicle Routing Problem with Time Windows for Milk Collection

Abstract

This study conducted for a leading dairy company in Türkiye aimed to optimize the milk collection process by addressing the Vehicle Routing Problem (VRP) which is essential for the efficient collection of perishable products like milk in the dairy industry. Key constraints considered included vehicle capacity the number of vehicles milk quality collection time windows delivery speed route optimization and cost minimization. A mathematical model was initially developed and solved using IBM ILOG CPLEX, however as the number of collection locations increased solution times became impractical. To overcome this challenge the Benders Decomposition Algorithm was employed significantly improving solution efficiency. The application of this method led to enhanced collection efficiency and cost-effectiveness delivering substantial operational benefits to the dairy company. © 2025 Elsevier B.V. All rights reserved.