Iron ore substitution and carbon emission reduction by scrap steel recycling under carbon neutrality goal

As the world's largest steel production country, China annually produces more than 50% of global steel, which relies on around 70% of iron ore imports in the last decade. Promoting scrap steel recycling is essential to reduce the heavy dependence on imported iron ore and simultaneously mitigate CO2 emissions. This study used the GCAM model (Global Change Analysis Model) and the dynamic MFA model to quantify the amount of scrap steel that would be generated under the carbon neutrality goal (CNG). Furthermore, we provided different scrap steel recycling scenarios to explore the potential of iron ore savings and the reduction of CO2 emissions during 2020–2060. The results showed that the annual steel production would be reduced to 525.2 Mt in 2060 under CNG, but a total of 470.3 Mt of iron ore would still be required annually. The quantity of scrap steel generated is expected to increase annually, reaching a cumulative total of 16941.37 Mt between 2020 and 2060. With increasing the scrap steel recycling rate, under optimal conditions, savings in iron ore and mitigation of CO2 emissions could reach 6447.1 and 3132.4 Mt, respectively, cumulatively during the period from 2020 to 2060. Furthermore, iron ore demand could be met domestically by 2050, eliminating the need for imports. By extending the lifetime of construction, the overall reduction in steel production would be 1064.1 Mt from 2020 to 2060. Meanwhile, 1883.1 Mt of iron ore can be saved and 889.6 Mt of CO2 can be mitigated accumulatively.