A geological reconnaissance of electrical and electronic waste as a source for rare earth metals

Sandra R Mueller,Patrick A Wäger,Rolf Widmer,Ian D Williams

doi:10.1016/j.wasman.2015.03.038

Abstract

The mining of material resources requires knowledge about geogenic and anthropogenic deposits, in particular on the location of the deposits with the comparatively highest concentration of raw materials. In this study, we develop a framework that allows the establishment of analogies between geological and anthropogenic processes. These analogies were applied to three selected products containing rare earth elements (REE) in order to identify the most concentrated deposits in the anthropogenic cycle. The three identified anthropogenic deposits were characterised according to criteria such as “host rock”, “REE mineralisation” and “age of mineralisation”, i.e. regarding their “geological” setting. The results of this characterisation demonstrated that anthropogenic deposits have both a higher concentration of REE and a longer mine life than the evaluated geogenic deposit (Mount Weld, Australia). The results were further evaluated by comparison with the geological knowledge category of the United Nations Framework Classification for Fossil Energy and Mineral Reserves and Resources 2009 (UNFC-2009) to determine the confidence level in the deposit quantities. The application of our approach to the three selected cases shows a potential for recovery of REE in anthropogenic deposits; however, further exploration of both potential and limitations is required.

Highlights

Metallic raw materials are crucial to modern society: their mobilisation increased almost 19-fold from 1900 to 2005 (Graedel et al, 2012)
Considering the lifespan of the planet, the exploitation of these ores1 is a recent phenomenon, but it increased exponentially during the last two hundred years (Arndt and Ganino, 2012). Once these geological heritages are consumed, they cannot be replaced in any period significant to Abbreviations: EoL, end-of-life; Eu2O3, europium oxide; Nd2Fe14B, Neodymium– Iron–Boron; REE, rare earth elements; REO, rare earth oxides; UNEP, United Nations Environment Programme; UNFC, United Nations Economic Commission for Europe; USDOE, U.S Department of Energy; EEE, electrical and electronic equipment; WEEE, waste electrical and electronic equipment
In the study presented here, we develop a framework that allows the establishment of analogies between geological and anthropogenic processes

Summary

Introduction

Metallic raw materials are crucial to modern society: their mobilisation increased almost 19-fold from 1900 to 2005 (Graedel et al, 2012). Considering the lifespan of the planet, the exploitation of these ores is a recent phenomenon, but it increased exponentially during the last two hundred years (Arndt and Ganino, 2012) Once these geological heritages are consumed, they cannot be replaced in any period significant to Abbreviations: EoL, end-of-life; Eu2O3, europium oxide; Nd2Fe14B, Neodymium– Iron–Boron; REE, rare earth elements; REO, rare earth oxides; UNEP, United Nations Environment Programme; UNFC, United Nations Economic Commission for Europe; USDOE, U.S Department of Energy; EEE, electrical and electronic equipment; WEEE, waste electrical and electronic equipment. Minerals are individual components within rocks that are generally defined according to their chemical composition and crystal structure (Nickel, 2005) They are the starting point for the production of metals such as rare earth elements (REE). Thereafter, an annual decline by 4.5% is expected until 2035

Methods

Results

Conclusion