Here, Frank van de Winkel, Market Strategy Manager Metal at Tomra Recycling, outlines the current aluminium recycling landscape and explains how, by embracing cutting-edge sorting technology, numerous industries can pave the way for a more circular economy.
In an era of heightened environmental consciousness and intensified global sustainability goals, the aluminium industry stands as a dynamic force for positive change. As companies race to reduce their carbon footprints and embrace more sustainable practices, aluminium recycling has emerged as a pivotal solution. This versatile metal – found in everything from beverage cans to aircraft parts – offers a unique opportunity to conserve resources, minimize environmental impact and drive operational efficiencies.
Aluminium exists in two primary forms: cast aluminium and wrought aluminium. Cast aluminium is characterized by its high silicon content, while wrought aluminium contains minimal silicon. When cast and wrought aluminium are combined, the resulting alloy is primarily used in the production of cast aluminium because there isn’t a straightforward or widely used method to completely remove silicon. This process, sometimes called ‘downcycling’ results in different products than those present in the scrap mix.
The source of aluminium significantly impacts its composition. Scrap aluminium feedstock can be categorized into two main types: post-production and post-consumer. These two categories, though both crucial to sustainable practices, differ significantly in their origins and characteristics.
Post-production scrap, as the name suggests, is generated during the manufacturing process itself. It often arises as by-products or offcuts in the production of industrial goods such as automobiles, construction materials and appliances. This type of scrap is typically in a relatively pure state, having not yet been exposed to general usage.
Conversely, post-consumer scrap originates from the end of a product’s lifecycle. It is generated by consumers who have used aluminium-based products and have subsequently discarded them. This type of scrap can come from various sources, including end-of-life vehicles, households, businesses and public spaces. Unlike post-production scrap, post-consumer scrap is often contaminated with various substances, such as food residues, dirt and other debris.
Recognizing these differences in the origins of the scrap allows recyclers to tailor their sorting and processing techniques accordingly, ensuring that the recycled aluminium meets the required standards for various applications.
The challenges of aluminium recycling
A primary obstacle in aluminium recycling is the difficulty of separating it from other metals once it has been combined in alloys. Given the vast array of aluminium alloys – with hundreds of different cast and wrought varieties – it is vital to maintain the scrap aluminium as close to its original composition, or at least to the desired composition of the final product.
Different aluminium alloys possess distinct properties, such as strength, corrosion resistance and malleability. By identifying the specific alloy of the aluminium being recycled, recyclers can optimize the recycling process to preserve these valuable characteristics and ensure that material is processed efficiently and cost-effectively. This knowledge enables reprocessors to produce recycled aluminium that is equivalent in quality and performance to primary aluminium, expanding its potential applications and increasing its market value.
Understanding the source of aluminium is crucial for maximizing recycling efficiency. By identifying potential contaminants or impurities, recyclers can implement targeted cleaning and sorting methods to remove these unwanted materials. This not only improves the quality of the recycled aluminium, but also reduces energy consumption and minimizes waste.
The power of precision sorting
Advanced metal sorting solutions are revolutionizing the recycling industry by transforming scrap into valuable resources. These sophisticated systems leverage cutting-edge technologies, such as X-ray Transmission (XRT) technology – a powerful tool used for sorting and analysing materials based on their atomic density – and artificial intelligence (AI) to accurately identify and separate various metals, ensuring high-purity outputs.
This precision sorting enables recycled aluminium to be used as a direct substitute for virgin material in various industries. From beverage cans to construction materials and automotive components, recycled aluminium can be seamlessly integrated into manufacturing processes without compromising product quality or performance. This not only conserves valuable resources, but also reduces the environmental impact associated with aluminium production.
Tomra’s Autosort Pulse is a prime example of such a solution. Leveraging advanced laser-induced breakdown spectroscopy (LIBS) technology, this innovative sorting system can rapidly analyse the composition of metal objects, distinguishing between different types, grades, and even alloys, closing another gap on the journey towards full material circularity. This enables high-throughput production of alloy scrap fractions, maximizing their economic value and paving the way for a more sustainable aluminium supply chain.
Another key benefit of Autosort Pulse is its ability to minimize contamination and subsequently enhance the value and marketability of the recycled materials. The system’s precision sorting reduces the risk of cross-contamination, safeguarding the integrity of recycled materials and ensuring that the recycled materials are suitable for their intended applications.
The high purity of the aluminium scrap fractions delivered by Autosort Pulse enables the material to be used in the aluminium smelting and production process without downgrading valuable materials. In extensive material testing at Tomra’s test centres and at customers’ plants, Autosort Pulse is consistently delivering purity levels of 95% and above.
Looking to the future
The growing demand for recycled aluminium is being driven by the shift towards lighter, more sustainable products, particularly in the automotive and construction industries. The shift to electric vehicles has further accelerated the demand for recycled aluminium. Government regulations and industry initiatives, such as the EU’s ban on CO2-emitting vehicles and its ambitious Green Deal targets, are driving the demand for recycled aluminium. This is part of efforts to reduce greenhouse gas emissions and promote a circular economy.
As many countries and regions strive to fulfil their pledges of achieving carbon neutrality by 2050, the role of recycling in meeting these targets cannot be overstated. Among the various materials that can be sustainably repurposed, aluminium is a particularly valuable resource. Its recycling process offers a significant reduction in energy consumption compared to primary production, leading to substantial cuts in carbon emissions.
Those core industries where aluminium is widely used – such as automotive, transportation and construction – have a unique opportunity to lead the transition to a circular economy, minimizing environmental impact and accelerating progress towards carbon neutrality.
The future of aluminium recycling lies not only in recycling production scrap, but also in substituting primary raw materials with secondary scrap. This will require continued significant advancements in processing technologies, particularly in alloy sorting. Some of our customers are already pioneering this approach by implementing our range of advanced metal sorting solutions to facilitate more efficient and precise recycling.
