Carbon footprint analysis and carbon reduction path research of automotive hot-dip galvanized sheet

Under the guidance of the "3060" dual-carbon goals, downstream automotive customers have clearly put forward requirements for carbon footprint disclosure of steel products. To accurately quantify the carbon emission level of automotive steel products, this paper took the life cycle assessment（LCA） method as the core, constructed a carbon footprint assessment model for automotive hot-dip galvanized sheets, conducted full-process quantitative accounting, and analyzed the characteristics of carbon emission contribution and carbon reduction potential. The accounting results show that the carbon footprint of producing 1 kg of hot-dip galvanized sheets is 2. 508 kg CO₂. From the perspective of life cycle stages, the production link accounts for the highest proportion of carbon emis‑sions, reaching 60%, the upstream raw material mining and energy production link ranks second, accounting for 38%, the transportation link accounts for the lowest proportion, only 2%. From the perspective of production pro‑cesses, the key carbon-emitting processes and their proportions are as follows, blast furnace process（26%）, sinter‑ing process（22%）, hot rolling process（14%）, steelmaking process（11%）, and galvanizing process（9%）. To further explore the carbon reduction paths of each production process unit, this paper took the intermediate products from the above five key processes as the objects of carbon footprint evaluation, and deeply analyzed their carbon foot‑print composition and carbon reduction potential space. Taking the existing process route of hot-dip galvanizing as the baseline scenario, carbon reduction scenario analysis was carried out focusing on "increasing the pellet ratio before ironmaking" and "improving the scrap steel ratio in steelmaking". The results show that when the full-process scrap steel ratio is increased to 50%（process limit value）, the carbon footprint of long-process automotive steel sheets can be reduced by 40% compared with the baseline value. If external purchase of green electricity is used in this scenario, the carbon footprint can be further reduced by 5%.