The international Zorba market is ever-changing and is being molded by government regulation across various regions. This has a direct impact on how shredded recycled aluminum is processed in the US, given that practices such as polishing Twitch are becoming more common.
The increase in industry transparency has also led to carbon emissions and metal recovery being key operating metrics. However, the future of recycled aluminum exports from the US seems subdued as domestic demand and consumption of recycled content and post-consumer recycled material increases. Domestic demand is expected to continue trending up as it brings reductions in both energy consumption and carbon emissions. Still, challenges at the sorting level have kept the industry from realizing its full potential.
Challenges
Zorba processing is not a simple task, as it involves seven major metals and an array of non-metallics that must be managed. Sink-float plants create a clean Twitch package but are expensive and delicate to run. Meanwhile, dry systems are more affordable but produce an inferior quality product. Landfill requirements are also to be considered – understanding better ways to reuse the material is an opportunity that needs a better solution.
Today, OEMs have also switched their focus to capturing post-consumer recycled content, which allows the processing of the past into the future by upgrading and not downcycling materials. Thus, ensuring wrought alloys go back into wrought applications is the future. The only reason it hasn’t been done earlier is limitations in sortation technology.
Till now, sorting was based on density-type sensors, which cannot tell the difference between a structural low copper alloy and other wrought alloys. It is common to see a wheel alloy in a wrought package coming off an X-ray Transmission machine; the growth of structural castings in modern cars will only further pollute packages created with today’s technology.
Still, better sortation practices will lead to improved profitability on lower alloying costs and gains in operating expenses.
Sorting through technology
New technology used by Sortera Alloys approaches sorting based on multiple sensors rather than only one sensor, which solves only a small part of the problem. The transparency of recycled materials can also be improved by combining artificial intelligence and multiple sensor technologies.
The recycling industry has never known the actual detailed composition of a mixed package, just the rough chemical content. Thus, data is key to the industry as it tries to meet targets for upcycling, considering that the recycled material being processed is around 13.5 years old and contains very little, if any, auto body sheet. Still, consumers are seeking end-of-life post-consumer recycled material.
The missing link is the composition of the shredded recycled material and knowing whether it is worth separating to meet recycled content goals. Optical sensors can help distinguish wrought and cast alloys, allowing the company to capture low copper cast alloys. In doing so, a low silicon package is put together, which can be utilized by consumers in automotive body sheet applications.
Ben Pope is the vice president, Commercialization at Sortera Alloys and can be contacted at benpope@sorteraalloys.com.