Systemic Analysis of Rare Earth Elements - flows and stocks – ASTER

Several eco-technologies of primary importance (windpower mills, low consumption lamps, electric motors …), use rare earth elements (REE ; for example neodymium, dysprosium or samarium in the permanent magnets of windpower mills or hybrid vehicles). These substances are referred to as “critical” in that they combine scarcity with economic impact intensity in the event of penury. Yet more than 97% of the world production of REEs is controlled by China, while this country has approximately 30% of estimated world reserves. Restrictions in terms of Chinese REE export quotas are a concern for governments and recent initiatives (for example the COMES in France or the European Raw Materials Initiative) aim at reducing this dependence. The objective of the ASTER project (Systemic Analysis of Rare Earth Elements – flows and stocks) is to provide a global vision of REE criticity, based on a dynamic analysis of the flows and stocks of these substances (SFA) in the anthroposphere and thus to contribute to improving the safety of supply of these substances that are essential for certain eco-technologies. A review of the literature relative to SFA shows that the lithosphere (the subsurface) is invariably considered as a source of flux but never as a stock. It is because it associates, among others, the French leader of REE applications and recycling (Rhodia) and the public body of reference in Earth Sciences (BRGM) that the ASTER project is able to offer a more holistic analysis of the question of REE criticity by combining both primary (extractable from the subsurface) and secondary (recycled) resources. One of the project’s primary deliverables is the delivery of so-called “Sankey” diagrams, that provide a visualization of substance flows and stocks in various compartments of the economy (primary production, imports, manufacturing, recycling, …). The thicknesses of the flux arrows being proportional to flux importance, these diagrams are particularly easy to read by non-technical decision-makers, a feature which guarantees a better dissemination of project results. These fluxes and stocks being typically affected by uncertainties related to the incomplete/imprecise nature of available information (such uncertainties are qualified as “epistemic” as opposed to “stochastic” uncertainties related to randomness), the tools offered by possibility theory, that are particularly tailored for representing expert knowledge, will be exploited. Hence the ASTER project refers to a “change of paradigm” (school of thought) on several counts:

-Taking into account, in a same dynamic analysis of flows and stocks of REEs in the anthroposphere , both primary resources related to potential reserves of REEs (on the French territory but also at an international scale) and secondary resources (recovered from the waste stream).
-Qualification of epistemic uncertainties related to these flows and stocks.

The consortium of the ASTER project is set up in order to bring together the main French actors of the REE thematic. In addition to Rhodia, the BRGM, and LaSalle Beauvais, the consortium includes the IRIT laboratory of the University Paul Sabatier of Toulouse, international reference in the treatment of epistemic uncertainties and BIO IS, a consulting company which in 2010 performed the study for ADEME on the recycling of rare earths. Thus a complementary objective of the ASTER project is to set the basis for a national-level research group with respect to strategic metal supply safety.