Recycling revolution: AT&S turns copper into gold in Leoben

For two years now, the Austrian microelectronics manufacturer AT&S has been recovering valuable copper and process chemicals from production wastewater at its site in Leoben Hinterberg using a self-developed, state-of-the-art wastewater recycling system. As this not only protects the environment and reduces the consumption of raw materials, but also generates money through the sale of the recycled copper. AT&S is already working on new improvements to the system: two new shredders enable the recycling of solid waste at the site and the return of the recycled copper to production. The upgraded system exploits synergies and allows copper waste water from the AT&S site in Fehring to be treated.

With a comprehensive sustainability strategy and considerable investments, AT&S has been working for a long time to minimize the ecological footprint of its production sites worldwide. The plants in Austria play a pioneering role in this and, especially with the AERIS recycling system that specialists at the Leoben site have developed. AERIS has received a Supplier Award from AIRBUS in 2023 and sets new standards for sustainable electronics manufacturing: The system filters 100 to 120 tons of copper and up to 75 tons of acid out of the production wastewater in Hinterberg, all of which can be reused.

“We need fewer raw materials and simultaneously reduce the cost for the disposal of waste water as well as the emissions of CO2 for production and transportation. In this way, we are fulfilling our promise to develop sustainable technology. This is a success across the board for AT&S,” says Konstantin Kern, who developed AERIS with his team.

The new recycling system has already proven itself in regular production at the Hinterberg site and AT&S engineers have come up with some new ideas to make the system even more efficient. The recycling team has implemented some improvements in the last couple of months by purchasing two new copper shredders and starting to transport used electrolyte from production in Fehring to Hinterberg for copper recovery. “We have just qualified the shredders. They allow us to cut copper plates from production that are up to 0.5 centimeters thick into flakes. We can now recover 45 additional tons of copper from the waste. Since last December, we have also been receiving around 2000 liters of used electrolyte per month from our plant in Ferhing, from which we can recover copper worth 500 euros. Fehring saves the same amount again in disposal costs,” says Konstantin Kern.

In-house technology

AT&S has developed AERIS entirely in-house and holds eight patents related to the system. “This means we can also implement our solution at other sites or even provide it to other companies under license. For copper concentrates from the plating processes, the system pays for itself after just one year. For copper concentrates from etching processes, it is seven years. It is a very interesting innovation from an economic point of view. The full capacity of our current system is around one ton of copper recovery per day. We can reach this figure in a few years if production develops as we expect. That would be a nice milestone for our recycling program,” says Konstantin.

The first step in this direction happens this year. In Hinterberg, AT&S experts will put the waste water management system on a new footing so that the waste water streams from all areas of production will be accessible to AERIS. “Currently, around five tons of copper are still left in the sludge every month. The copper is difficult to isolate and we expect to recover around 2.5 additional tons per month as a result of the adjustments,” says Konstantin. As with all changes to the recycling system, the team will examine this innovation in detail and fine-tune it accordingly. After that, the system can be adapted at other locations.