UNISORT Film and UNISORT BlackScan from the STEINERT Group sort plastic foils and black plastics
The Steinert Group, a specialist for magnet and sensor technology, has launched two new sorting machines on the market. UniSort Film and UniSort BlackScan offer operators of processing and sorting plants new approaches to solutions: Plastic films can be detected and reliably sorted out at high belt speeds thanks to Active Object Control (AOC). The application of HSI technology means that valuable black plastics can now be detected.
The task of sorting PVC films, biologically based films, agricultural films and biologically degradable films is a problem for many sorting operations. Why? Because due to their lightness and form, they lift off from the acceleration belt and spin around uncontrolled, overlapping one another and ensuring that they cannot be reliably sorted out of the material flow. Operators frequently reduce the belt speed to combat this problem, with the consequence that the throughput of the corresponding sorting lines is reduced. Until now. The Steinert Group has taken up this challenge and developed UniSort Film for just this job.
Active Object Control stabilizes material on the conveyor belt
Active Object Control (AOC) is an important component of the UniSort Film: It“s a stabilizing system that uses airflow to influence the material being sorted on the belt, enabling a degree of control over the material“s flight parabola in the area of the catcher hood. „The great advantage of this solution is that the operation now runs with the higher throughput and that increased sorting performance can also be achieved,“ explains Astrid Schröder, an applications specialist at STEINERT. „The investment for the UniSort Film pays off quickly.“
A high-speed camera analyses and classifies objects
The conveyor belt carries the plastic films to the heart of the sorting system: to the UniSort Film. The machine“s controller and air conditioner are located in the two side parts, which also serve as supports for the detection unit (HSI) – so there is no need for an additional switchgear cabinet.
The sensor is a near infrared camera that works using Hyperspectral Imaging Technology (HSI). Different plastic parts are analysed and classified on the basis of their specific and reflected light spectra. The specific spectra for PET bottles and shells, PE, PP and other types of plastic are stored in a database. The system is operated via an intuitively understandable touchscreen display in one of the side parts. Here the operator can set which plastic parts are to be sorted out of the material flow.
Line-scan camera with 320 pixels
Unlike many of its competitors, STEINERT uses a line-scan camera. „Rather than scanning the belt point by point, this camera measures 320 pixels across the entire belt width simultaneously,“ explains Schröder. This distinguishes the system from classic systems, which use a point-by-point scanning technology that relies on optomechanical components such as rotating mirrors.
Thanks to the high resolution of the HSI technology, it is even possible to recognize the smallest nuances of the NIR spectrum. This capability is necessary for tasks including sorting PET bottles and shells and also for sorting black plastics. The result is a better sorting performance for operators of processing and sorting systems
Targeted blasts of compressed air sort out plastic parts
So how is a part sorted out once it has been detected? The answer is provided by a compressed air system with a nozzle bar equipped with high-speed-valves. The software passes the system the exact position data of the plastic parts to be sorted out, and the system opens the corresponding valve within a fraction of a second. A directed blast of air sorts the target material out. A range of different nozzle bar spacings are available: Nozzle spacings of between 12 and 31 millimetres are normally used, depending on the material size.
UniSort BlackScan even recognizes black plastic parts
Sorting operations are familiar with the problem: classic systems using near-infrared technology cannot recognize black plastic parts. This is because the reflected spectrum in the infrared wavelength region is not adequate for recognition. The parts are not sorted out, remain in the residue fraction, and cannot be separated by the processor.
The STEINERT Group has changed the game with the UniSort BlackScan. The sorting machine basically functions in exactly the same way as the standard UniSort . But there“s one essential difference: Thanks to the use of HSI technology and a more complex evaluation of the spectrum, it is now possible to recognize objects without a spectrum and soot-blackened objects of down to 200 millimetres in size. This offers a huge advantage for sorting plant operators. „For the first time, it“s now possible to recognize and sort out black plastics as well as the normal types of plastic and so create additional value added,“ explains applications specialist Schröder. At the same time, the system reduces disposal costs, as the black plastic parts no longer land in the residual fraction. „The UniSort BlackScan is an essential basis for all technologies that will one day be used for sorting dark plastics of all types.“
STEINERT blickt auf eine 126-jährige Geschichte zurück: 1889 in Köln gegründet, gehört das Familienunternehmen mittlerweile zu den weltweit führenden Unternehmen in der anspruchsvollen Magnet-Separation und innovativen Sensor-Sortierung. STEINERT erzielt mit rund 300 Mitarbeitern einen Jahresumsatz von 100 Millionen Euro. Neben 50 Vertriebskooperationen und Joint Ventures befinden sich überall auf der Welt Tochtergesellschaften – in Australien, Brasilien, Japan, in den USA, China und Südafrika.
Kontakt
STEINERT Elektromagnetbau GmbH
Julie Zavazalova
Widdersdorfer Str. 329-331
50933 Köln
+49 221 4984-108
Zavazalova@steinert.de
http://www.steinert.de