Table 1 Energy use and carbon emission factors for Fe, Al, and Cu production

From: Resource, economic, and carbon benefits of end-of-life trucks’ urban mining in China

Metal

Indictor

Unit

Primary production

Secondary production

Range of all factors

Al

Energy use

MJ kg⁻¹ material⁻¹

47.00

2.40

±20%

Carbon emission

t CO₂ t⁻¹ material⁻¹

8.80

0.29

±20%

Fe

Energy use

MJ kg⁻¹ material⁻¹

14.00

5.0

0

±20%

Carbon emission

t CO₂ t⁻¹ material⁻¹

1.67

0.70

±20%

Cu

Energy use

MJ kg⁻¹ material⁻¹

16.90

6.30

±20%

Carbon emission

t CO₂ t⁻¹ material⁻¹

1.25

0.44

±20%

  1. In China, mature metallurgical technologies have relatively limited room for improvement in reducing energy consumption, while the carbon emission factor of energy use is likely to decline gradually in the future, in line with China’s 2060 carbon neutrality goal. Therefore, this study examined the changes in carbon emissions from primary and secondary production under fixed and decreasing factors. Detailed setting about the fixed and decreasing factors from 2025 to 2050 is provided in Supplementary Tables 79. Data is mainly sourced from Asmatulu et al.72, and with some estimates based on Hertwich et al.30, Liu et al.48, Watari et al.94, and Song et al.19.