A Heuristic Approach for the Maritime Inventory Routing Problem with Decarbonization Analysis

This work proposes a heuristic framework to address the Maritime Inventory Routing Problem (MIRP), while demonstrating its applicability to challenges in maritime decarbonization. The method integrates Beam Search (BS) and Iterated Local Search (ILS) within an open-source environment. Its contribution lies not in the individual use of BS or ILS, but in their tailored adaptation and combined design, which capture the interdependence between routing and inventory decisions. To the best of our knowledge, this is the first fully self-contained heuristic approach capable of handling all 72 MIRPLib Group 2 instances, an available benchmark dataset, without relying on commercial solvers. Building upon this methodological contribution, the heuristic is applied to assess decarbonization strategies in maritime logistics. Additionally, the method is being adapted into a simheuristic, integrating the deterministic algorithm with Monte Carlo Simulation, tailored for the stochastic MIRP to account for uncertainties in sailing times and port demand and production rates.