Recycling : New Technology in Metal Recycling

In 2011, the Finnish company ZenRobotics introduced the first fully automated robot for waste sorting. By using metal detectors, 3D laser technology and spectroscopic imaging, the precision of sorting parts was significantly improved, paving the way for the entire recycling industry.

In 2014 the "Heavy Picker" was introduced –a dedicatedproduct for metal recycling. Since then the system has been continuously improved and optimized using AI. With the use of three robot arms, the system can now perform up to 6.000 sorting processes per hour. In comparison an experienced manual sorter only manages 200 picksper hour. Another advantage is that the “Heavy Picker” can be seamlessly integrated into existing systems or used as a stand-alone sorting line.

Scandinavia is amongst the leading players in the innovation of new technologies in metal recycling. The Norwegian company TOMRA, for example, has specialized in the recycling of aluminum scrap. The importance of this raw material was emphasized by the Covid-pandemic, when aluminum became a scarce resource all over the world. As a result, aluminum producers are becoming increasingly reliant on high-quality recycled material. And that's where TOMRA promises to deliver with its X-TRACT series.

The system uses an electrical X-ray source that generates broadband radiation. This radiation penetrates the material and strikes an X-ray camera that uses two independent sensor lines with different spectral sensitivities. In this way, the atomic density of the materials can be identified. This technology contributes to a reduction in the purchase costs of the raw material, since, on the one hand, the materials no longer have to have an overly strict composition and, on the other hand, less material than usual is processed. As a result, scrap can be purchased at a lower price with a lower quality and then cleaned.

Its German-based daughter company TOMRA-Sorting in 2018 introduced a new laser object detection (LOD) system for its “AutoSort” and “Finder” product line, increasing the detection accuracy of existing equipment by an additional four percent. Among other applications LOD also has been designed to separate black rubber, glass and plastic material from nonferrous zorba and zurik products, allowing to turn these commodities into more valuable revenue streams while reducing the number of manual pickers.

The Austrian-based company Redwave has been using XRF technology for years to determine the chemistry of a sample. Initially, the technology was primarily used in glass sorting –with the introduction of Redwave XRF/C, a standalone solution for metal sorting was developed.

Compared to other technologies, moisture, coloration as well as surface impurities have no negative influence on the metal detection. The sorting processes, with the aid of advanced software algorithms, produce high-purity metal fractions, which can be sold directly and profitably. This innovative sorting solution has already been successfully implemented in various sorting lines and plants worldwide.

Since the beginning of the millennium, portable and flexible handheld devices based on XRF technology have been widely used as a flexible and cost-saving solution in metal recycling. Over the years, the technology has improved significantly and is now the leading portable instrumentwhen it comes to stainless, high temps and red metals. However, since the introduction of handheld LIBS devices in 2015 –they use a fast chemical analysis technique with a short laser pulse –an alternative has been established, especially for the analysis of light metals such as aluminum or magnesium. Thermo Scientific introduced the "NitonApollo" in 2019, which is leading the way for individual and flexible applications. Especially recyclers dealing with heavy loads or space constraints are relying on the laser guns to analyze metals on their composition within a few seconds. Another majoradvantage of this technology is that no sampling is necessary and the measurement can be carried out without contact.

According to studies, the demand for metal raw materials will rise rapidly in the coming years. Aluminum on its own will require an additional 360 million metric tons of raw material over the next 20 years to meet demand from the industry. Above all, key industries of the future, such as the electric automotive sector, are dependent on the supply of light metals. In the new age of climate change, recycling metals is becoming increasingly important, but it also holds great economic opportunities. For example, recycling rare metals from electronic wasteis thirteen times cheaper than extracting them from mines, according to the American Chemical Society. By using new methods as well as artificial intelligence, metal recycling is becoming a key player in the fight against global warming.