The answer to the aluminium industry’s emissions issue? Aluminium’s infinite recyclability

Aluminium is renowned for its nearly infinite recyclability; this attribute not only makes it ideal to reduce waste generally, but also presents an opportunity to reduce emissions in its own sector. The Aluminium for Climate initiative’s recent publication Closing the Gap for Aluminium Emissions: Technologies to Accelerate Deep Decarbonization of Direct Emissions highlights the need for breakthrough technology to mitigate direct emissions in aluminium production.

However, as the aluminium industry seeks to decarbonize, emissions resulting from production are only one part of the equation. The sector must also improve circularity to substantially decrease demand for high-carbon primary aluminium. The International Aluminium Institute (IAI) projects that global demand for aluminium will grow by more than 80% by 2050. Over 90% of current aluminium emissions are associated with primary production. But secondary, or recycled, aluminium uses just 5% of the energy required for primary production.

If recycling rates remain the same, the increase in primary aluminium production will mean a rise in sectoral emissions of around 45%. Much of this demand stems from the transition to a green economy, because aluminium is an essential material for sectors such as electricity transmission and renewables. Additionally, as the global population continues to grow, increasing demand for consumer goods (e.g. packaging, automobiles) will boost the need for aluminium.

In a circular business model, aluminium is recovered at the end of a product’s life and constantly cycled through the value chain rather than entering a landfill. Collection rates of end-of-life aluminium sit around 70% globally, although they vary greatly by region and product type. Around 7 million tonnes of aluminium are not recycled each year; with no change in recycling rates, this is projected to reach 17 million tonnes per year by 2050. Recovery of 95% of this material would reduce demand for primary aluminium by 15%, avoiding 250 million tonnes of CO2 emissions each year.

There is opportunity for the industry to collaborate across the value chain and create circular business models that benefit all parties. In response to increasing consumer demand for recycled materials, companies are making ambitious commitments to raise the percentage of recycled content in their products. This indicates a likely rise in demand for secondary aluminium, leading to a more competitive environment for access to scrap.

Sources for aluminium scrap include packaging, technology, construction, and the transport industry. The greatest opportunity to increase the availability and quality of scrap is in consumer packaging and the automotive sector. Together, transportation and packaging account for around 58% of post-consumer aluminium scrap intake, around 11.6 million tonnes annually.

Collection of automotive scrap in many parts of the world is relatively straightforward, as consumers are legally required to dispose of cars properly. The challenge with automotive scrap lies in sorting the aluminium alloys to retain the quality and value of the original components.

Currently, end-of-life automobiles undergo a process known as fragmentation; cars go through a shredder resulting in many small fragments of mixed alloys. Fragmentation results in a single stream of aluminium scrap that is composed of a mix of alloys; while this mixed scrap can be recycled for some components, such as engine blocks, the market for this type of scrap is declining due to the rise of electric vehicles (EVs).

Instead, the market is increasingly demanding high-quality, well-sorted scrap. Today, fragments can be sorted through: 1) robotic sorting that uses visual identification of scrap to automate the sorting process; 2) infrared sorting to analyze material composition; 3) X-ray fluorescence to sort based on elemental composition; and 4) eddy-current sorting using magnetic fields.

The greatest opportunity to improve the value of automotive scrap is starting at the beginning and designing components with the intention of making them easy to recycle in a manner that retains the quality of the aluminium. This will require collaboration across the value chain – from automotive manufacturers to collectors and recyclers.

Aluminium companies are already working to improve closed-loop recycling. For example, Constellium is leading Project ISA3, a French initiative in partnership with Groupe Renault, ESI Group, Institut de Soudure (Welding Institute) and the University of Lorraine. This €7 million project will develop lightweight, recyclable and cost-efficient aluminium solutions for the automotive market – focusing on alloys and solutions that enable closed-loop recycling.

Another unmissable opportunity for additional aluminium scrap collection is post-consumer packaging scrap. Unlike automotive scrap, improving collection and sorting of packaging scrap heavily relies on consumer behaviour, policy, and local recycling infrastructure.

Packaging scrap collection rates in many parts of the world are already high (e.g. Brazil at 97.4%). Increasing collection rates will require innovative, convenient return systems that motivate customer participation.

Some parts of the world, particularly developing countries, have extremely high recycling rates (>90%), yet rely on manual collection and sorting. This raises additional concerns around child labour and safe working conditions. It is necessary to ensure that increased demand for scrap does not jeopardize workers’ safety while protecting their right to work.

Ball Corporation, in collaboration with Novelis, Tomra and others, published a vision to achieve a 90% recycling rate and 85% recycled content for aluminium cans by 2030. Since packaging aluminium has high recycling yields and is sorted with inexpensive technologies, the biggest opportunity is continuing to increase collection. Deposit return systems offer the ability to collect close to 100% of packaging aluminium and will be implemented across Europe in the next few years.

While technology is key to improving collection, it must be supported by meaningful policy and consumer education. The US offers the biggest opportunity to implement a modern national bottle bill, and there is momentum among industry players and recyclers to enable that ambitious policy.

Conclusion

The greatest barrier to transformational change in aluminium sorting and recycling remains the cost of improving existing technologies and building a convenient and comprehensive infrastructure. Companies need to justify the economic viability of investing in high-cost sorting technologies; the investment must be supported by consumer demand for secondary aluminium.

Like many technologies, aluminium recycling requires local solutions. Factors such as population density, consumption trends, product lifetime and access to scrap all influence which technologies should be put in place. Moving forward, the aluminium industry should work together to share best practices between regions and improve global collection and sorting.