Commercially Available Sorting Technology for Plastic Scrap

In Plastic recycling the value of recycled raw material depends upon the properties of the material, material having properties similar to virgin raw material of same polymer get maximum price and vice versa. To get good quality recycled the input raw material of the polymer should be pure.

In post consumer waste there are many types of contamination which has to be removed before extruding it. Apart from dirt, dust, wood, metals, etc Polymer of other type is also a major contamination for Example to manufacture Reprocessed HDPE Granules, it should not contain Polypropylene which will drastically reduce the mechanical properties of Reprocessed HDPE Granules or PET should not contain PVC.

To remove these contamination the material should sorted very precisely to get the pure stream of input raw material. Below mentioned are the commercially available technologies for sorting different types of Plastic Material based on their polymer type.

NIR (Near Infrared) Sorting: -

These machines are available by many manufacturers which can sort plastic material as a whole or flakes based on it polymer type like HDPE, PP, PVC, PET, Etc by using Infrared Camera and Spectroscopy to detect the material and Air Electors to Eject the unwanted material.

Electrostatic Separators: -

Different plastic material have different electrostatic properties based on which it is separated. In this technology the raw material is electrically charged by triboelectric process and separated using HIGH Voltage power supplies which attract the opposite charged material.

Hot Oven Separator: -

This method can be used specifically to separate PET and PVC based on their melting point. Here the melting point of PVC is less than PET so when the material is passed on metal belt having temperate above melting point of PVC and below meting point of PET then PVC sticks to the belt and can be scrapped out and PET go ahead.

Baffled Oscillatory Sorting System ( BOSS)

This is newly developed technology which can separate HDPE and PP using plain water as sorting medium which use technology called Baffled Oscillation.

http://www.bharatplastics.net

Reprocessed HDPE Granules, Reprocessed PP Granules

Priscilla James is the Ceo of Chi Chi Gallery Design