Evaluation of Cutting Technologies for Robotic and Sustainable Ship Recycling*

Ship recycling, which involves dismantling of ships, contributes to the circular economy by recycling materials from decommissioned ships. However, despite the existence of international regulations, ships are still dismantled on beaches under rudimentary conditions. Workers manually cut the ship’s metal plates with oxy-fuel torches, often resulting in accidents, injuries, and occupational diseases due to unsafe working conditions and exposure to toxic substances. Coastal ecosystems and local communities are exposed to toxic spills and pollution due to lack of containment. We believe that a sustainable ship dismantling process that prioritizes worker safety and environmental responsibility can be achieved through robotic cutting of metal blocks. As a first step toward realizing this robotic cutting concept, this paper examines three cutting methods (oxy-fuel, plasma, and waterjet) based on four factors: environmental impact, safety, technical feasibility, and cost. The paper’s findings, based on these design considerations, including human and environmental factors, indicate that plasma cutting technology is best suited for the proposed robotic approach to sustainable ship dismantling.