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Quantifying urban mines in Europe and related implications for the metal-energy-climate change nexus

Periodic Reporting for period 1 - QUMEC (Quantifying urban mines in Europe and related implications for the metal-energy-climate change nexus)

Reporting period: 2016-06-01 to 2018-05-31

The limits to an indefinite growth based on a linear production-consumption model have become evident in the recent years when the demand for natural resources and associated environmental burdens have increased to unsustainable levels. Improving cognition of the socio-economic metabolism is priority and driven by growing interest to comprehend the effects of the anthroposphere on the environment, and the awareness of the value of the natural capital to provide materials and energy for human wellbeing.
This need is of particular interest for metals, for which potential supply shortages due to the run-out of natural deposits and scarcity of many metals in nature have raised severe concerns of long-term sustainability. This vulnerability to supply risk is amplified for countries highly dependent on imports, notably many EU Member States.
In this context, the recycling of secondary material sources (also known as in-use stock) can help to reduce Europe’s reliance on primary deposits and to move towards a closure of material cycles in accordance with the Circular Economy approach. While securing access to essential resources, end-of-life recycling is also expected to contrast global warming by avoiding the use of large amounts of energy, which would be required in primary metal production because recycling is often significantly less energy-intensive.
The project has proposed an exemplary research line that merges complementary drivers in the assessment of the interlinkages between metals, energy, and climate change to estimate the size of current in-use stock for four selected metals; evaluate future opportunities and barriers to their recycling, and assess potentials for energy savings and greenhouse gas (GHG) emissions reduction attainable through end-of-life recycling. Copper, indium, neodymium, and europium were selected in virtue of the considerable insights that could be provided in light of their use in energy generation, distribution and use.
Setting up long-term strategies for efficient recovery of secondary resources and material circularity requires quantitative estimates of the total material amount available for recycling and annual scrap generation at end-of-life. This pre-condition is seldom available in statistics and builds upon the characterisation of anthropogenic material cycles. To this aim, material flow analysis (MFA) was applied to investigate physical flows and stocks along the whole metal lifecycle in the EU-28. For each target metal, the analysis was extended to the most recent years possible. The conservation of mass performed for each year of investigation provided an estimate of the cumulative metal in-use stock.
Life cycle assessment (LCA) was then employed to address the environmental sustainability dimension associated with resource recycling. Combining the elemental information from the MFA models with LCA inventories, the potential for energy savings and GHG emissions reduction were estimated both from current recycling and from a region-wide implementation of best available techniques. Uncertainty analysis was carried out to validate the robustness of the model created.
The project enabled to identify the application segments embedding the largest amount of secondary resources, which were found to be greater than the known domestic natural deposits in some cases. In addition, it was estimated that the annual flow of post-consumer scrap of the four metals could cover a substantial fraction of the metals demand by domestic manufacturers. Consequently, a virtual basis for closing the metal cycles seems to exist in the EU-28. While securing sustainable access to vital raw materials, pursuing efficient recycling would clearly benefit the environment, with substantial potentials for energy savings and GHG emissions reduction.
However, the end-of-life recycling performance is currently inexistent for indium, neodymium, and europium, and far from perfect conditions for copper. Establishing and maintaining a competitive recycling chain would require to tackle effectively the existing challenges to recycling including inefficiencies from product design to waste management. Ultimately, economic issues are often the main limitation to setting recycling strategies for these metals so that the development of feasible business models in collaboration with recyclers is needful.
Lastly, historic demand for the four metals was evidently related to economic wealth and population. As both drivers are expected to increase in the coming years, securing sustainable supply of the target metals through recycling might be not enough to reduce the pressure on the environment. In particular, a scenario analysis carried out for copper estimated that climate forcing could be significantly impacted by the anticipated energy requirement to meet the explored demand.
The planned strategy for the dissemination of the results was aimed at reaching a wide impact both in the scientific community and non-scientific audience. To this aim, open access is ensured to all the peer-reviewed scientific publications, while attending main conferences in the field enabled to present the results to the research community. Communication and outreach activities through training seminars and educational campaigns were devoted to a direct engagement with young students and the civil society. In addition, active participation to national and international workshops maximised the visibility of the project and provided the opportunity to communicate with policymakers, associations of producers, and industry experts.
The expanded historic perspective adopted on the production and consumption pattern of the four metals contributed significantly to the understanding of their socio-economic metabolism in the EU-28. Considering the rapid growth of the demand for these metals, the results of this project complemented and improved the existing knowledge on anthropogenic cycles.
MFA and LCA are the basis upon which a more sustainable development can be built. The discussion on demand-supply dynamics, technical barriers to recycling and attainable potentials for energy saving and GHG emissions reduction provides scientific evidence, analysis and support to designing mitigation policies to climate challenge, resource efficiency and raw materials actions for material circularity.
The transition towards a low-carbon society includes the implementation of clean technologies for energy generation, distribution and use, in which copper, indium, neodymium and europium play a vital role. Thus, strengthening the competitiveness and resilience of the European economy makes the underlying interlinkages between metal demand, supply, and environmental implications particularly relevant and opportune for the elements selected.
In this view, the results constitute an evidence-based knowledge addressing (i) the potential impacts of secondary sources to meet the future demand for greener energy systems, and (ii) the potential energy savings and GHG emissions reduction associated with secondary sources to make recycling the preferable and more environmentally sustainable route for metal supply.
For these reasons, the project is expected to be of interest for a wide spectrum of stakeholders from governance, industry, and academia towards the achievement of a sustainable growth through innovation and strategies for resource efficiency.
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