Critical metals are central to a number of technologies that underpin many low-carbon energy systems. In light of the current scarcity of some of these raw materials, the European Commission has classified a list of 20 resources1 as being of critical importance (EC 2014). There are a number of ways that Europe can reduce its exposure to potential supply bottlenecks for these critical raw materials, including by investing in primary mining and conducting research into the substitution of these materials with more readily available alternatives. The third most important approach is the recovery of raw materials from waste products though ‘urban mining’ or recycling.
In the report Critical Metals in the Path towards the Decarbonisation of the EU Energy Sector, the Joint Research Centre - the European Commission’s in-house science service, highlights the importance of policy measures to increase the reuse, recycling and waste reduction of critical metals with a view to mitigating future potential supply risks. To provide this policy support, the EC set out its vision for Europe as a recycling society in its Communication on the Thematic Strategy on the Prevention and Recycling of Waste (COM/2005/666). This was followed in 2008 by the Raw Materials Initiative(RMI)2 which established an integrated strategy to respond to the different challenges related to access to non-energy and non-agricultural raw materials.
The RMI is based on three pillars: ensuring a level playing field in access to resources in third countries; fostering sustainable supply of raw materials from European sources, and boosting resource efficiency and recycling. With regard specifically to waste electrical and electronic equipment (WEEE), which is the main source of recycled critical metals, the first EC Directive (2002/96/EC) came into force in 2003 and aimed to increase the recycling and re-use of WEEE by providing for the creation of collection schemes allowing consumers to return WEEE free of charge. A revised version of this Directive (2012/19/EU) entered into effect at the start of 2014 and aimed to tackle the rapidly increasing waste stream.
According to the United Nations Environmental Programme report Critical Metals for Future Sustainable Technologies and their Recycling Potential, recycling not only increases resource efficiency and reduces the likelihood of supply shortages - it also reduces the overall environmental impact associated with the life cycle of critical metals, as recycling of metals usually has much lower environmental impacts (lower energy demand, greenhouse gas emissions etc.) than the production of primary metals from natural ores.3 The UNEP report identifies two distinct types of recycling: end-of-life (post-consumer) treatment of waste, and recovery of metals during processing and manufacturing. The latter is an efficiency measure that is frequently incorporated into manufacturing processes, particularly those involving expensive raw materials. The materials recovered in pre-consumer waste are generally easier to exploit, as they are less dispersed and contaminated than in post-consumer waste.
Post-consumer recovery of critical metals is more difficult due to the low metal concentrations in waste flows and the fact that the critical metal is usually a minor composition in a complex material system involving many other metals, plastics etc. Another issue that hampers the recovery of metals from electrical and electronic equipment is the fact that the recovery is often carried out in developing countries where the collections systems in place are sub-optimal. Furthermore, the long lifetimes of many products containing critical metals, and the newness of some of the technologies in question, mean that post-consumer recycling will only be possible in the longer term. Nevertheless, the UNEP report notes that, despite these restrictions, the post-consumer recycling of many critical metals is at an advanced stage thanks to continuous improvements in recycling technologies.
About 3.1 million tonnes of WEEE was reportedly collected in the EU in 2008, but it is estimated that around 7 to 8 million tonnes of WEEE was generated, which implies a collection rate about 40%.4 The UNEP report estimates the current post-consumer recycling rates for rare earths, gallium and tellurium globally at less than 1%, compared to over 50% for many base and precious metals. Germany’s Öko Institute, which produced the report on behalf of UNEP, has identified a set of preconditions for the optimisation of recycling of critical materials. These include enlarging existing recycling capacity and the development and implementation of new recycling technologies. The European Union is addressing this need through projects such as RARE35, which is focusing on breakthrough recycling processes for permanent magnets and lamp phosphors, which represent over70% of the rare earths market by value. The European Rare Earth (Magnet) Recycling Network6 was set up in 2013 to train researchers in basic and applied rare-earth sciences, with an emphasis on extraction and separation methods and rare-earth metallurgy, recycling methods and the principles of urban mining. This network aims to ensure that Europe has the human resources required by the growing European rare-earth industry.
The UNEP report also calls for the accelerated improvement of international recycling infrastructures and notes that the main problems with the current recycling of critical metals are the lack of suitable take-back and collecting systems for post-consumer waste flows in most parts of the world. This is fraught with consequent health risks for the people involved in recycling, and significant losses of valuable critical metals. State-of-the-art integrated smelter-refineries can achieve a high recovery yields (over 95% for precious metals with co-recovery of a number of special metals and even of some indium)7 and innovative dedicated recovery processes for batteries can achieve yields of over 90% for cobalt and also recover lithium. However, less sophisticated end-processing can result in significant losses, and resolving this problem will require the transfer of know-how and technology transfer from the developed world.
A report from the Copenhagen Resource Institute on present and potential future recycling of critical metals in WEEE in Europe shows that, while the current recycling of critical metals in WEEE is very low, this could increase threefold to 3,000 tonnes in 2015. The report notes that the revised WEEE Directive should have a positive impact on recycling of critical metals, with a minimum collection of 45% to be achieved within four years and 65% in seven to nine years. However, the integrated optimization of the whole value chain including product design, collection, dismantling, pre-processing and smelting will be crucial if these targets are to be met.
2 COM(2008) 699 Communication “The raw materials initiative - meeting our critical needs for growth and jobs in Europe”.