A study on key raw materials and their flows “through the EU economy, as raw materials or as parts of basic materials, components or products” has been produced by BIO Intelligence Service for the European Commission, DG GROW (BIO by Deloitte (2015) Study on Data for a Raw Material System Analysis: Roadmap and Test of the Fully Operational MSA for Raw Materials. Prepared for the European Commission, DG GROW).

It contains Sankey diagrams for 28 materials considered critical or important to European economy, such as cobalt, lithium, or tungsten.

The flows of these materials into the EU-28 geographical area (imports) as well as out of the EU-28 (exports) are displayed for all substances in the same way. Recycling of the substance within Europe is represented as a loop, leading to a kind of see-saw-ish diagram. Additions to in-use (e.g. the substance being part of a product in use) and a certain amount of the substance being disposed off (e.g. as waste) are also shown as arrows to the right. Below is the diagram for cobalt. Flows are in tonnes for the year 2012 (t/y).

All Sankey diagrams are color-coded the same-way, providing additional information whether the material (in the case above: cobalt) is imported as raw material or as part of a product, and whether it is exported as processed material, waste, or also as part of a product.

The study can be downloaded from this page or directly here (PDF, 6 MB)

This presentation from 2015 by Alicia Valero of the Spanish Research Centre for Energy Resources and Consumption (CIRCE, Zaragoza) is on critical materials, minerals scarcity, recycling and a “thermodynamic cradle-to-cradle approach”.

It features two Sankey-style diagrams depicting the mineral balance of the European Union (UE).

This first one is a Sankey diagram for the mineral balance without fossil fuels (‘Diagrama de Sankey para el balance mineral de la UE sin combustibles fósiles’).

Data is for the year 2011, Flows are shown in tons. Iron and limestone dominate the picture with 77% of the input. Limestone is produced (extracted) mainly within Europe, while iron is mostly imported.

The second Sankey diagram is a scarcity diagram (‘Diagrama de rareza para el balance mineral de la UE sin combustibles fósiles’) and takes into account thermodynamic exergy to obtain (mine) the minerals. Although it depicts aluminium, gold, ion, nickel and the likes, flows are shown in an en(x)ergy unit (Mtoe).

Iron and limestone which seemed to be the most important mass-wise only constitute some 10% of the input. Aluminium and potash seem to be much more difficult to produce. Rare earth elements (REE) are not included in this diagram.

The author points out that it is important to not only look at materials from a mass perspective. Looking at materials availability taking into account thermodynamic exergy paints a different picture of the real cost and scarcity.

For those interested, please check out the presentation (in Spanish) here.