Metal Recycling : TOMRA Recycling and Gerhard Lang Recycling GmbH join forces to pioneer sorting of aluminium alloys

Gerhard Lang Recycling GmbH, the leading German metal recycling company has installed an AUTOSORT™ PULSE unit at its metal sorting facility in south-west Germany as part of a research project funded by the German Federal Ministry of Economics and Technology.

The KANAL project* is an ambitious initiative to close the loop on aluminium scrap from car production. TOMRA, Gerhard Lang Recycling GmbH, Pforzheim University of Applied Sciences and engineers from Jeanvré have joined forces for the €3.9 million project to prove that aluminium production scrap can be effectively sorted and transformed into high-quality secondary aluminium. The consortium is using TOMRA's dynamic laser-induced plasma spectroscopy (Dynamic LIBS) technology. Gerhard Lang Recycling GmbH is a research and field validation partner in this pioneering project. 

The plant feedstock consists of stamping scrap - the excess metal material removed during the metal stamping process - generated during the production of automotive parts and panels. Although highly efficient, the stamping process inevitably generates significant amounts of scrap, with an estimated 30-50% of the material being discarded. The aluminium scrap consists of a mixture of 5xxx (high-magnesium) and 6xxx (low-magnesium) wrought aluminium alloys, which are used in various components within the automotive industry.

On arrival at Gerhard Lang Recycling GmbH's metal sorting facility in Gaggenau, Germany, the material is shredded before undergoing a multi-stage magnetic separation process to remove the ferrous metals. The non-ferrous material is then fed into the AUTOSORT™ PULSE for further sorting.

Prior to the installation of the AUTOSORT™ PULSE, the team at Gerhard Lang Recycling GmbH sold the mixed material to aluminium manufacturers immediately after the shredding process, as there was no efficient solution on the market for separating the high and low magnesium aluminium alloys. With the AUTOSORT™ PULSE now in place, and thanks to TOMRA's dynamic laser induced breakdown spectroscopy (Dynamic LIBS) technology, these alloys are sorted into different products, allowing Gerhard Lang Recycling GmbH to produce exceptionally high purity 5xxx and 6xxx aluminium scrap. 

The identical appearance and density of alloys renders traditional sorting methods ineffective. However, the AUTOSORT™ PULSE separation process is based on precise analysis of the elemental composition of each material and advanced dynamic laser detection, enabling it to distinguish between alloys.

In addition, object singulation allows the AUTOSORT™ PULSE to accurately identify and separate even overlapping and adjacent materials, maximising the yield and efficiency of the sorting process. Its 3D object scanning feature recognises the shape, height and position of the object and identifies the ideal firing point for the Dynamic LIBS laser. This laser offers two focus modes: multi-point, where the laser shoots in a line across the sample, and single-point, where the laser drills down to a specific spot, providing ideal detection conditions. The latter, developed by TOMRA, has demonstrated superior performance in tests.

Another key benefit of the AUTOSORTTM PULSE is its ability to minimise contamination, thereby increasing the value and marketability of the recycled materials. The system's precision sorting reduces the risk of cross-contamination, safeguarding the integrity of the recycled materials and ensuring that they are suitable for their intended applications.

Gerhard Lang Recycling GmbH consulted TOMRA's metals experts before investing in the plant's new aluminium sorting process. The development of the project took several years, with initial discussions starting around 2018.

Maximilian Lang, Managing Director of Gerhard Lang Recycling GmbH, comments: "With the integration of the AUTOSORT™ PULSE, we are able to process a throughput of around 4-7 tonnes per hour and achieve exceptionally high purity levels of over 95% and potentially up to 97%. As a result, our material is suitable for use in aluminium production without downgrading. We can now sell the recovered materials to leading aluminium producers and recyclers for direct incorporation into the production of new aluminium alloys. What's more, we are looking at the potential to explore additional applications for other aluminium alloys.

Frank van de Winkel, Market Strategy Manager - Metal at TOMRA Recycling, adds: "This is a very exciting project for TOMRA to be involved in and we are delighted that Gerhard Lang Recycling GmbH is reaping the benefits that our AUTOSORT™ PULSE can offer. With the European Union's commitment to climate neutrality by 2050, as outlined in the Green Deal, and the specific target of a 55% reduction in greenhouse gas emissions by 2030 under the 'Fit for 55' initiative, there has never been a more important time to explore ways to make the aluminium supply chain more sustainable.

"Our AUTOSORT™ PULSE system enables aluminium producers to increase the use of recycled aluminium in their production processes. This innovative solution unlocks access to previously untapped sources of scrap, enabling the recovery of high quality, alloy-true recycled aluminium. By preventing downcycling and preserving material value, we are closing another gap towards full material circularity. The successful implementation of our technology at the Gerhard Lang Recycling GmbH plant demonstrates the feasibility of closed-loop recycling for production scrap and paves the way for a less carbon-intensive aluminium supply chain".

*KANAL stands for "Kreislaufsystem für funktionales Aluminium-Neuschrottrecycling aus der Automobilproduktion mittels LIPS", which translates as "Circular system for functional aluminium scrap recycling from automotive production using LIBS". The project number is 03LB4015B and the project name is "KANAL - Kreislaufsystem für funktionales Aluminium-Neuschrottrecycling aus der Automobilproduktion mittels LIPS".