Beyond Operational Emissions: Assessing Ship Recycling as a Decarbonization Pillar for the Global Merchant Fleet

Maritime transport contributes 2.9% of global greenhouse gas emissions, traditionally evaluated through operational fuel cycles while neglecting lifecycle impacts. This study redefines merchant ship recycling as a strategic front-end pillar for global decarbonization by assessing Embodied Carbon Trade-offs. Utilizing a mixed PRISMA systematic and semi-systematic methodology of literature from 2019–2025, we analyzed bulk carriers, container ships, and tankers across six thematic clusters. Our findings demonstrate that scenarios involving the potential decommissioning of up to 22.2% of the global merchant fleet exceeding 20 years of age could significantly mitigate lifecycle emissions by displacing primary iron-ore smelting with circular electric arc furnace marine-steel recovery. Crucially, this environmental dividend is non-linear and bound by regional energy matrices; under deeply decarbonized grids, this technological displacement can theoretically yield an upper-bound 72% emissions reduction, whereas fossil-heavy power supplies significantly diminish net mitigation margins. Practically, this research provides an operational roadmap for shipowners and regulators navigating the Hong Kong Convention and carbon border mechanisms. This work concludes that sustainable shipbreaking has the potential to function as an economically viable, strategic reservoir of low-carbon raw materials essential for achieving international net-zero targets throughout the entire shipping structural lifecycle.