Recycling, Urban Mines and Eco-design

Raw materials and recycling are key issues in the ecological transition. The development of the circular economy to counter the excessive use of materials at all levels is essential.

The objective of the DIM is to contribute to the emergence of technologies necessary for life cycles of materials that respect the environment and health. This includes strategies to find alternative raw materials and achieving significant gains in recycling critical resources. It is also a matter of thinking about reducing the environmental footprint of manufacturing processes (solvents, acids, energy), with equal performance, in order to meet societal demands. Finally, this line of work encompasses the work needed to meet, from the design stage, to the pressure exerted on the environment by the poor management of end-of-life materials.  The aim here is to propose strong research actions in favour of a global development of the circular economy, with a view to optimised management of the territories’ resources, reducing their environmental impact and fostering the emergence of virtuous economic and social models.

These are therefore three sub-themes that structure this axis:

• Techniques for recycling waste electrical and electronic equipment (WEEE). WEEE are often made up partly of rare materials and the two current recycling methods are not eco-compatible: pyrometallurgy is very energy-intensive and releases huge quantities of toxic gases, and hydrometallurgy requires large quantities of corrosive and toxic effluents which must then be treated and purified. Thus, reducing the toxicity of effluents and developing more water-efficient processes are avenues of interest.
• Recycling and energy recovery, particularly in the case of incineration of household waste. For example, it is a question of developing processes for extracting machefers, which are very rich in metal oxides and sources of reusable raw materials (iron, copper, zinc, aluminium, etc.). It may also be possible to optimize the mechanical recycling of thermoplastic and thermosetting polymers through original recovery strategies by mixing with other polymers before processing. This recycling method, which consists in crushing the polymer and then reshaping it, generally causes a degradation of its mechanical performance.

• Eco-design, including value for money, biomass exploitation, biofuel production or polymer development.