A two-phase heuristic for an in-port ship routing problem with tank allocation

This paper addresses an in-port ship routing problem with tank allocation that arises in the chemical shipping industry. The aim is to optimize a tanker's port call operation that integrates sequencing decisions for visiting terminals and allocating cargo loads to available tanks while taking into account cargo time windows, terminal draft limits and various tank allocation restrictions. We model the problem as a Traveling Salesman Problem with Pickups and Deliveries, Time Windows, Draft Limits and Tank Allocation (TSPPD-TWDLTA), and propose a two-phase heuristic to solve it. Computational studies show that the heuristic is able to provide good solutions to real-sized in-port routing problems with tank allocation in chemical shipping in a reasonable amount of time.