Scenario assessment of neodymium recycling in Japan based on substance flow analysis and future demand forecast

Shinichirou Morimoto,Hiroshi Kuroki,Aya Ishigaki,Hirokazu Narita

doi:10.1007/s10163-021-01277-6

Abstract

With the increasing demand for energy-saving technologies, neodymium-iron-boron magnets have been widely utilized in high-efficiency motors. However, the reserves of neodymium, which is a rare earth element (REE), are limited; thus, a strategy for scaling up the REE supply is highly required. In this study, a scenario assessment was conducted to evaluate the effect of material recycling of neodymium from final product waste. Domestic substance flow analysis of neodymium was conducted by focusing on the waste flow of the final product. Moreover, the demand and waste of neodymium until 2050 were forecasted using various multivariate analysis methods. The results showed that the domestic waste of neodymium was forecasted to be 3866–4217 tons/year by 2050. However, material recycling of neodymium from final product waste may cause an additional increase in production by “circular economy rebound”. Considering that CO2 reduction has also been a global challenge to prevent global warming, the rebound effect was calculated. Therefore, a scenario assessment was conducted to evaluate the influence of this rebound effect by estimating the CO2 reduction. The results of this study are expected to make a significant contribution to the establishment of a new strategy for neodymium recycling.

Highlights

The demand for mineral resources, such as rare earth elements (REEs) and other critical materials, has been rapidly increasing owing to the growing population and industrial development
This evaluation will be more effective by scenario assessment considering the waste flow and rebound effect based on the future forecast of final product-specific demand and waste volume based on economic and population changes
Neodymium accounted for approximately 18% of all REE produced [19], the production of neodymium increased from 27,480 REO tons/year in 2017 to 27,900 REO tons/ year in 2018

Summary

Introduction

The demand for mineral resources, such as rare earth elements (REEs) and other critical materials, has been rapidly increasing owing to the growing population and industrial development. Analyzing the rebound effect of the recycling amount, as well as the effect of CO2 reduction, is necessary to evaluate the true potential of material recycling This evaluation will be more effective by scenario assessment considering the waste flow and rebound effect based on the future forecast of final product-specific demand and waste volume based on economic and population changes. The SFA method and future forecast used has been done in past studies, but the novelty of this study lies in the assessment of future scenarios considering the relationship between real recycling potential and the rebound effect. This was achieved by detailed SFA of domestic waste flow. The results obtained in this study can contribute to creating recycling strategies as well as international standards by realistic evaluation of material recycling potential, which has not yet been studied in the past

Background

Findings

Conclusion