Coordinating Interprovincial Scrap Supply for Technology Transition to Minimize Carbon Emissions of China's Iron and Steel Industry.

Provincial inherent heterogeneity in resource endowment, steel demand, and managerial guidance poses not only challenges but also chances to the decarbonization of China's iron and steel industry (ISI). Previous studies have primarily concentrated on the technological dimension at the national level or plant level but have neglected potential regional synergies. This study proposed a framework encompassing macroeconomic models and multi-objective algorithms to optimize interprovincial allocation of scrap resources for coordinating the steelmaking process transition, aiming to minimize total carbon emissions from ISI. Results indicate that optimizing scrap allocation can reduce carbon emissions by 173.97-215.66 million tons, achieving a 99% reduction by 2060 compared to 2020 levels. Under the coordination strategy, 19 out of 28 provinces can achieve carbon neutrality and realize more than 90% pollutant reduction in the ISI. Notably, provinces such as Hebei, Inner Mongolia, Shanxi, Heilongjiang, and Liaoning still need to import more scrap resources and implement innovative low-carbon technologies. Finally, we propose interprovincial coordinated transition strategies, including regional integration management, national data platform, and preferential economic instrument. This work guides national and provincial administrations to formulate differentiated low-carbon transition targets and collaborative actions in ISI, which can be also applied to other substantially heterogeneous industries to achieve carbon neutrality.