Illustrating the supply chain of dysprosium in China through material flow analysis

Dysprosium (Dy) is a critical rare earth element. However, its supply, consumption, trade, and recycling along the entire supply chain have not been clearly investigated, especially for China where most Dy is produced and used. This study quantified the Dy flows and stocks in mainland China during 1990--2019. Key findings are as follows: (1) domestic Dy demand increased by 16-fold during 2004-2019, driven by green technologies; (2) Dy mine production failed to grow significantly after 2010 under intensified environmental regulations; (3) China's total Dy exports increased steadily, with exported commodities changing from upstream to downstream prod-ucts; (4) in-use Dy stocks grew by 15-fold during 2006-2019, implicating big potentials of urban mining, but commercial recycling systems have not been established. This study reveals the importance of supply-demand monitoring, environmental governance, and global cooperation to Dy industries, and highlights the necessity of material flow analysis for improving metal supply chain management.