Green inventory-routing problem of perishable items with age-related price and the possibility of renting vehicles

Abstract

This paper considers a green inventory-routing problem (IRP) for perishable items in a two-level supply chain including a distributor (manufacturer/plant) and some retailers. Each item has a fixed expiry date. The product price depends on its age. The retailer demand for each product is fixed. The product cannot be sold after the expiry date. The possibility of hiring extra space for holding excessive amounts of inventory and hiring vehicles to exploit the advantage of the higher number of deliveries are considered. The problem is formulated to a mixed-integer linear programming (MILP) model. Some small, medium and large-sized random generated samples are solved using OPL software and a proposed combined ant-generic algorithm. The results show the positive effect of partial outsourcing on the amount of profit. Furthermore, the volume of orders is influenced by taking the environmental effects of transportation into account. Copyright © 2023 Inderscience Enterprises Ltd.