Worth of metal gleaning in mining and recycling for mineral conservation

• Recovering metal losses in mining and recycling contributes to mineral conservation.
• Importance of increasing recovery rates is indicated by substance flow analysis.
• Gleaning was more important in mining than in recycling in 2000 except for lead.
• Gleaning in recycling will become important in future due to increased discard.

Mitigating mineral extraction is considered to be an important challenge in prolonging resource supplies and protecting the environment at mining sites. This challenge can be faced by retaining metal resources within the anthroposphere with adequate technologies and policies for reducing losses to the environment. In mining and mineral processing, considerable amounts of metals are lost as tailings. In recycling, metal recovery from end-of-life products is limited by economic and technological restrictions. In this study, we evaluate the potential for mitigating mineral extraction by reducing the loss rates in mining and recycling. In this study, global substance flow analysis is conducted for seven metals and the importance of recycling is determined for each metal. Furthermore, the change in potential recycling in the future is discussed in combination with dynamic substance flow analysis. We found that reducing the loss rate in recycling could not fully realize mineral conservation in the year 2000, except in the case of lead. However, we also showed that it will become important as the metal discard increases in the future. The framework of this study supports the sustainable use of metals by introducing the right technologies and policies at the right time.