Sorting System Identifies Plastics With Spectroscopy

Canon announced its series of plastic sorting equipment, the TR Series. The equipment applies Raman spectroscopy technology to moving objects with a tracking mechanism to collectively detect the material types of plastic fragments with high accuracy, even when black plastic pieces are mixed with other colors, which has been conventionally challenging. The company is now accepting orders from the market for the TR Series which includes the TR-S1510.

Raman spectroscopy is a detection method that enables material detection by using a laser to obtain molecular information about the illuminated substance. Technically, this method is applicable to black plastic. However, due to the a limited amount of reflection by the black plastic pieces, the measurement time is too long relative to the speed and throughput required to effectively sort all the pieces regardless of their colors at recycling plants. Therefore, the practical application of Raman spectroscopy to sorting black plastic has so far proven difficult.

By combining Raman spectroscopy with Canon’s measurement and control equipment, the company has developed a tracking technology which scans laser light toward the pieces, thus ensuring there is enough measurement time required for each piece of plastic according to its color and achieving high speed and high accuracy overall. With this new system, the materials of black plastic pieces that were challenging to identify using the conventional near-infrared method can now be identified even when mixed with other colors, thereby helping to improve the productivity of recycling plants.

This new product maintains a conveyor speed of 1.5 meters per second and can sort up to 1 ton of plastic per hour. According to Canon, it can be customized according to a customer’s throughput and installation space by changing the module that tracks and measures the plastic pieces or the combination of conveyor belts.