Alutrade achieves breakthrough: Recovers 99% pure aluminium using X-TRACT™

Alutrade achieved 99 per cent pure aluminium for use in secondary aluminium production thanks to the X-TRACT™, TOMRA's most sophisticated x-ray metals sorting equipment. The UK-based aluminium recycling company became the first firm to benefit from X-TRACT, the advanced new sensor-based sorting technology from TOMRA. The X-TRACT™ was installed in March 2021 at Alutrade's Oldbury recycling facility in Birmingham, which handles 42,000 tonnes of garbage annually.

Remelts located all over the world are among Alutrade's clients. They require the highest purity grade of aluminium product for their remelting process since any heavy metal presence impacts the melt parameters.

The infeed material is first pre-shredded into smaller pieces of around one to two metres in length at Alutrade's Oldbury facility before being further shredded by a hammer mill. The following sorting stage involves separating the metals into ferrous and non-ferrous metals using magnets and eddy current separators to remove any impurities.

“Investing in the new X-TRACT™ has enabled us to close the loop on the recycling process as much as possible, converting aluminium back into aluminium for use in high-grade aluminium products so that in effect, a window frame can be recycled into a new window frame,” added Andrew Powell, Director at Alutrade LTD.

After magnetic separation, the desired fraction of aluminium is processed, sorted, and recovered using a combination of TOMRA sensor-based sorting machines. Two TOMRA X-TRACT™  machines from a previous generation, installed in 2017 and 2018, are configured to capture a bigger proportion of aluminium that is >30mm, while the new machine removes any heavy metal content from a lower fraction of aluminium that is 10–30mm. The older and newer X-TRACT™ devices separate any heavy metals by sorting metals based on the difference in atomic density.

“With low operational costs, improved safety and superior sorting capabilities, the new X-TRACT™ definitely stands out in terms of the aluminium recycling solutions available in the global metals recycling market,” added Andrew Powell.

The new X-TRACT™  can separate fractions to 5mm at even greater purity levels because of revolutionary x-ray sensor architecture. It also features significantly better x-ray capabilities while still using the same method of distinguishing metals by atomic density as the previous model. The software-based approach may ensure superior remelt grade recycled aluminium by ejecting the heavy metal impurities.

With its latest generation X-TRACT™ unit, one can sort materials significantly more quickly (up to 3.8 metres per second) and with more capacity per square metre. A high-power (up to 1,000w) x-ray source can handle various applications and grain sizes. At the same time, a novel high-acutance XRT sensor guarantees sharper detection and faster integration times for increased throughput. By expanding the trajectory of the sorted items, an enlarged separation chamber lowers material loss, and a revised catcher lid guarantees safer access and quicker maintenance.