Sakai, S. (2015) Presented at 3rd International Conference on Final Sinks, Taipei, Taiwan, August 25, 2015
Abstract
The management of end-of-life vehicles (ELVs) has become an important global issue because ELV
contains resource and/or hazard substances. We examined the element-contents in one ELV unit
based on the survey results of dismantling hybrid electric vehicles (HEVs), electric vehicles (EVs),
and conventional vehicles. Then substance flow model during ELVs management cycle (from ELV
generation to automobile shredder residue (ASR) generation) was developed. As results, metals were
often found more in HEVs than conventional vehicles following rare metals and rare earth metals:
Co, Ni, Y, La, Ce, Pr, Nd, and Dy. Total REE content in HEV was 3, 100 g, the largest of the four
ELVs, while that in the typical conventional vehicle was 14 g. This was because NiMH battery in
HEV contained La, Ce, and Nd. These results suggest that the value of ELVs will increase in the
future as more HEVs and EVs are in the stage of end-of-life. Precious metal contents (sum of Rh,
Pd, Pt, Ag, and Au) ranged between 5.5 g and 6.1 g and did not differ between vehicle types. It
should be noted that ELV also contained hazardous substances such as Pb. The content of Pb content
in the typical conventional vehicle manufactured in 1998 was estimated to be 610 g. These elements
were also portioned to ASR. Estimated results of elements contained in ASR indicated that the
development of methods to collect valuable substances effectively before shredding and to control
hazardous substances is very important. For instance, by improving the separation rate of 5 parts
(printed circuit boards, catalytic converter, air compressor, power steering, and hybrid transmission)
at dismantling process, 610 g-REEs (20% of total amount) in HEV and 17 g-REEs (approximately
100% of total amount) in EV could be potentially recovered. Furthermore, considering lifecycle of
vehicle (both vehicle use and end-of-life stages), HEV showed lower total material requirement
(TMR), 61 tons than conventional vehicle, 105 tons.