Multidimensional sustainability implications of alternative iron and steel industry decarbonization strategies in China

Abstract

The urgency of a rapid and deep decarbonization of the iron and steel (IS) industry cannot be overstated in pursuing China's carbon neutrality target. Beyond CO₂ emissions, the IS industry is also responsible for numerous non-climate impacts. We explored the impacts of alternative decarbonization options of the IS industry on economic cost, water, energy, CO_2, and air pollutant emissions from a systematic perspective. While all decarbonization pathways yield co-benefits on air pollutants emissions for the IS industry, the profiles of carbon leakage and spillover effect depend strongly on technology choice. Mitigation scenarios focusing on hydrogen-based direct reduction result in increases of CO₂, SO₂, and NO_x emissions from upstream energy supply. In CCS-led scenarios, fuel substitution could result in an expansion of charcoal-making and corresponding emissions of particulate matter. Thus, policymakers must consider the proper combination of upstream energy supply chain and decarbonization options for IS to avoid undesirable outcomes.