Flake sorting is the final stage in the bottle sorting process and takes place once the infeed material has been shredded, screened, washed and dried. Historically, Tomra Sorting Recycling’s flake sorting capabilities focused on the recovery of PET flakes from mixed plastics, but thanks to the heightened performance offered by the new Innosort Flake, Tomra Sorting Recycling can now also offer a full optical sorting line consisting of both bottle and flake sorting for polyolefins (PO), with perfectly aligned machines. Autosort is used to pre-sort the material then Innosort Flake is used for flake sorting.
Whereas the original Innosort Flake which Tomra launched in late 2018 had a total width of either 1 or 1.5 metres and was designed solely for PET flake sorting, the new edition of Innosort Flake is 2 metres wide and uses Tomra’s Near Infrared (NIR) Flying Beam PO-specific and Dual Full Colour Camera technology to deliver high throughput. Flying Beam is the only NIR technology on the market which allows automatic continuous signal correction and ensures the most stable and reliable sorting performance, along with the lowest maintenance and energy consumption.
The new NIR sensor technology offers a unique solution for PO applications. PO flakes are sorted by material and colour, and the PO-specific sensor used in our Flying Beam patented technology works in unison with the dual-full colour-camera technology to gather enough spectral information to accurately sort PP and PE flakes as small as 2mm. Using a front and rear camera set up allows Tomra to see the colour of each flake and identify even the tiniest of details, such as prints or ink. The unit can purify both the PE stream and the PP stream by identifying and removing the unwanted polymer contamination, as well as colour impurities. Any left-over contaminants are removed, resulting in unparalleled purity levels that meet both the standards demanded by current industry legislation and end customers.
And, for high-end applications such as bottle-to-bottle recycling where the contamination level of the infeed material is low but the quality requirements are particularly high, another flake sorting solution from Tomra, namely Autosort Flake can be used to achieve both extremely high purity and high, stable throughputs. Autosort Flake simultaneously detects material, colour and metal.