Christian Hagelüken

What Do We Know About Metal Recycling Rates

The recycling of metals is widely viewed as a fruitful sustainability strategy, but little information is available on the degree to which recycling is actually taking place. This article provides an overview on the current knowledge of recycling rates for 60 metals. We propose various recycling metrics, discuss relevant aspects of recycling processes, and present current estimates on global end‐of‐life recycling rates (EOL‐RR; i.e., the percentage of a metal in discards that is actually recycled), recycled content (RC), and old scrap ratios (OSRs; i.e., the share of old scrap in the total scrap flow). Because of increases in metal use over time and long metal in‐use lifetimes, many RC values are low and will remain so for the foreseeable future. Because of relatively low efficiencies in the collection and processing of most discarded products, inherent limitations in recycling processes, and the fact that primary material is often relatively abundant and low‐cost (which thereby keeps down the price of scrap), many EOL‐RRs are very low: Only for 18 metals (silver, aluminum, gold, cobalt, chromium, copper, iron, manganese, niobium, nickel, lead, palladium, platinum, rhenium, rhodium, tin, titanium, and zinc) is the EOL‐RR above 50% at present. Only for niobium, lead, and ruthenium is the RC above 50%, although 16 metals are in the 25% to 50% range. Thirteen metals have an OSR greater than 50%. These estimates may be used in considerations of whether recycling efficiencies can be improved; which metric could best encourage improved effectiveness in recycling; and an improved understanding of the dependence of recycling on economics, technology, and other factors.

Recycling of gold from electronics: Cost-effective use through ‘Design for Recycling’

With over 300 tonnes of gold used in electronics each year, end-of-life electronic equipment offers an important recycling potential for the secondary supply of gold. With gold concentrations reaching 300-350 g/t for mobile phone handsets and 200-250 g/t for computer circuit boards, this “urban mine” is significantly richer than what is available in primary ores.However, the “mineralogy” in scrap products is much different than in the conventional ores in a gold mine: Up to 60 different elements are closely interlinked in complex assemblies and sub-assemblies, and this requires specialised metallurgical processes with extensive offgas treatment to recover gold and a wide range of other metals cost effectively and in an environmentally sound way. Moreover, the logistics to “excavate” and “haul” the scrap products to the concentrator and further to the smelter are much more challenging than in the primary supply chain. Currently, only a small portion of old products is collected and directed into state-of-the art recycling chains. Significant improvements are needed here to fully utilise this secondary metal resource.The importance of the gold content of scrap electronics to the economics of recovery of gold and many other valuable metals is not always appreciated and this impacts on the “design for recycling” approach in selecting materials for new products, particularly in the European Union where the WEEE Directive aims to provide a closed loop economy. With a lower carbon footprint than primary-mined gold, recycled gold represents an important “green” source. The challenges faced in recycling electronic scrap to achieve a closed loop economy are discussed.

Improving metal returns and eco-efficiency in electronics recycling - a holistic approach for interface optimisation between pre-processing and integrated metals smelting and refining

The efficient recovery of precious and special metals from electronic scrap has significant benefits - economically, environmentally, but also under a resource conservation aspect. The yields of these metals could be substantially improved by higher collection rates, less scrap exports to regions with insufficient recycling structures, and by interface optimisation, as pointed out in this document

Secondary Raw Material Sources for Precious and Special Metals

Special and precious metals play a key role in modern societies as they are of specific importance for clean technologies and other high-tech equipment. The use of these “technology metals” has accelerated significantly over the past 30 years, and their sufficient future availability is crucial for building a more sustainable society with the help of technology. Recycling can contribute significantly to secure access to these metals, conserve metal resources, and mitigate potential temporary scarcities. If conducted in state-of-the-art processes, recycling of technology metals – which mostly occur in low ore concentrations only – offers as well considerable benefits compared to mining, with respect to energy, land, and water requirements.

Sustainable Resource Management in the Production Chain of Precious and Special Metals

Metals are classical examples of non-renewable resources, and their extraction from Earth by mining of ores cannot be seen as sustainable in the strict sense of the word. Mining, by definition, depletes the ore reserves. Through mineral processing and subsequent smelting and refining, ores are disintegrated, and the desired metals are isolated for use in the technosphere. Special and precious metals play a key role in modern societies as they are of specific importance for clean technologies and other high tech equipment. Important applications are information technology (IT), consumer electronics, as well as sustainable energy production such as photovoltaic (PV), wind turbines, fuel cells and batteries for hybrid or electric cars. They are crucial for more efficient energy production (in steam turbines), for lower environmental impact of transport (jet engines, car catalysts, particulate filters, sensors, control electronics), for improved process efficiency (catalysts, heat exchangers), and in medical and pharmaceutical applications. Figure 18.1 provides an overview of these main applications areas for selected metals and illustrates their significance for modern life. For example, electronic products can contain up to 60 different elements and in their entity are major demand drivers for precious and special metals: Just the annual sales of mobile phones and computers account e.g. for about 3% of the world mine production of gold and silver, 15% of palladium and over 20% of cobalt (Hageluken and Meskers 2008).

Closing the Loop for Rare Metals Used in Consumer Products: Opportunities and Challenges

Metals are classical examples of non-renewable resources, and their extraction from Earth by mining of ores cannot be seen as sustainable in the strict sense of the word. Mining, by definition, depletes the ore reserves. Through mineral processing and subsequent smelting and refining, ores are disintegrated, and the desired metals are isolated for use in the technosphere. Special and precious metals play a key role in modern societies as they are of specific importance for clean technologies and other high tech equipment. Important applications are information technology (IT), consumer electronics, as well as sustainable energy production such as photovoltaic (PV), wind turbines, fuel cells and batteries for hybrid or electric cars (contributions of Helmers (Part III), Schebek et al. (Part IV), Zepf et al. (Part VI) and Jagermann (Part VI). They are crucial for more efficient energy production (in steam turbines), for lower environmental impact of transport (jet engines, car catalysts, particulate filters, sensors, control electronics), for improved process efficiency (catalysts, heat exchangers), and in medical and pharmaceutical applications (Hageluken and Meskers 2008; Angerer et al. 2009).

Technologiemetalle – Systemische Voraussetzungen entlang der Recyclingkette

Der Boom in der Elektronik und bei anderen modernen Produkten hat zu einer starken Nachfrage vor allem nach Edel- und Sondermetallen gefuhrt. Doch in Europa gibt es fur diese „Technologiemetalle“ nach uber tausendjahriger Bergbautradition nur noch wenige Primarlagerstatten. Deshalb ist Versorgungssicherheit heute ein Thema.

Current Status of Natural Resources—An Overview

Two scenarios must be distinguished in an assessment of the supply of natural resources: the supply from domestic sources and the supply from foreign sources.

The Raw Material Requirements for Energy Systems

The new energy systems will be significantly more diverse as compared to the traditional energy technologies. Increasingly distinctive and mostly decentralized technologies will be added to the traditional generating technologies, such as coal and natural gas power stations, that dominate today’s energy systems.

Supply of Raw Materials and Effects of the Global Economy

The availability of raw materials is influenced by the supply- and demand-sides. Furthermore, the supply of raw materials—in general and including those for the new energy systems of the future—is dependent on developments in the global mining business and global economy. Political guidance can play an important role in this situation.