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http://dx.doi.org/10.7844/kirr.2019.28.3.26

Breakage and Surface Oxidation Characteristics of Waste NdFeB Magnet for Recycling  

Kim, Kwanho (DMR Convergence Research Center, Korea Institute of Geoscience and Mineral Resources)
Kim, Gahee (DMR Convergence Research Center, Korea Institute of Geoscience and Mineral Resources)
Lee, Hoon (Resource Recovery Research Center, Korea Institute of Geoscience and Mineral Resources)
Kang, Jungshin (DMR Convergence Research Center, Korea Institute of Geoscience and Mineral Resources)
Publication Information
Resources Recycling / v.28, no.3, 2019 , pp. 26-34 More about this Journal
Abstract
Due to the increasing demand of rare earth magnet for various application, it is predicted that the amount of waste rare earth magnet will increase sharply. The process of waste rare earth magnet recycling is mainly consisted of leaching and separation of rare earth element contained in the magnet. However, there is no study on the breakage characteristics of the waste rare earth magnet for production of magnet powder. Therefore, in this study, effective crushing/grinding process and breakage characteristics were investigated for waste rare earth magnet. In the case of jaw crusher, the particle size of magnet was effectively reduced without rapid oxidation. In ball mill grinding test, it was found that the grinding process was not performed properly at the early stage of grinding. Moreover, waste rare earth magnet showed very low specific rate of breakage(S) and high fraction of fine particle breakage distribution(B) compared to ordinary minerals. These results can be used as a basic data for developing crushing/grinding circuit of waste rare earth magnet.
Keywords
Rare earth magnet; NdFeB magnet; Grinding; Specific rate of breakage; Breakage distribution;
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