Total Material Requirement of Scrap Steel from End-of-Life Vehicles

The concept of total material requirement (TMR) is introduced in this study in order to quantify the recyclability of scrap steel from an end-of-life (EoL) vehicle. The specific TMRs for the recycling of scrap steels (urban ore TMR, UO-TMR) from the EoL vehicle are estimated for four cases: conventional press-method, shredder and separation method, additional recycling of scrap steel from automobile shredder residue (ASR) and all-recycling using the press method. The trade-off between the increase in functionality of recycled steel (i.e., decrease in influence of copper as a contaminant) and the additional inputs, such as pig iron or nickel required for the functional improvement, were also evaluated. The estimated UO-TMR ranged between 3.7 and 4.0 kg/kg, and the factors of “material itself” and “melting” were dominant. The effect of ASR input into an electric arc furnace, as part of an all-recycling scenario, was outweighed by additional lime input and the energy needed to heat glass materials. Considering dilution by cold pig iron, the shredder and separation method appears to be the most effective, in terms of TMR. Furthermore, the effectiveness is discussed, of both the dilution by pig iron and the addition of nickel for suppressing surface hot-shortness.