Sakai S.; Yano J.; Muroi T.; Watanabe N. (2014) Proceedings of 3RINCs and SWAPI 2014, pp. 2P-17
ABSTRACT
End-of-life vehicle management is important from the viewpoints of security and stable supply of resources since vehicle components contain various kinds of resources. This study aimed to clarify the recovery potential of the rare earth elements (REEs) Nd and Dy, which are used in and disposed off as end-of-life hybrid electric vehicles (HEVs); in particular, the Nd and Dy contents of the hybrid transmissions of HEVs was considered. The population balance model was applied for estimating the number of end-of-life HEVs generated in the period 2008-2030 by using statistical data. The results indicate that as of 2030, the number of disposed HEVs and that of HEVs in use will reach 0.46-0.60 million and 18-24 million, respectively; that is, the Nd and Dy contents of end-of-life HEVs will reach 73-94 ton and 28-36, respectively, while the HEVs in use will contain 2,800-3,800 ton of Nd and 1,100-1,500 ton of Dy. The amount of Nd and Dy disposed off in 2030 is estimated to increase to 20-25 times the amount in 2012. Furthermore, a large number of the HEVs will remain in use, and these may attain their end-of-life stages after 2030. Thus, considering the large amount of Nd and Dy resources trapped in the form of end-of-life HEVs, the development of a collection and recycling scheme for recovering these REEs is important.