Multi-objective analysis of the co-mitigation of CO2 and PM2.5 pollution by China's iron and steel industry

Abstract China has experienced serious fine particulate matter (PM 2.5 ) pollution in recent years, and carbon dioxide (CO 2 ) emissions must be controlled so that China can keep its pledge to reduce CO 2 emissions by 2030. The iron and steel industry is energy intensive and contributes significantly to PM 2.5 pollution in China. The simultaneous reduction of CO 2 emissions and PM 2.5 pollution while minimizing the total mitigation costs remains a crucial issue that must be resolved. Using a multi-objective analysis, we compared potential technology combinations based on various policy preferences and targets. Our results showed that policies designed to mitigate PM 2.5 pollution have substantial co-benefits for CO 2 emissions reductions. However, policies focused solely on reducing CO 2 emissions fail to effectively reduce PM 2.5 . Furthermore, CO 2 emissions reductions correspond to large financial costs, whereas PM 2.5 pollution reductions are less expensive. Our results suggest that under limited budgets, decision makers should prioritize PM 2.5 reductions because CO 2 reductions may be simultaneously achieved. Achieving large decreases in CO 2 emissions will require further technological innovations to reduce the cost threshold. Thus, China should focus on reducing PM pollution in the short term and prepare for the expected challenges associated with CO 2 reductions in the future.