摘要 |
<p>A method of sorting a mixed group of plastic articles, such as PET and PVC containers, involves individually subjecting each article to a beam of electromagnetic radiation, and detecting a change in the intensity of the beam. The measured intensity varies in a manner indicative of the crystallinity of the plastic from which the article is made, and hence identifies the type of plastic the article is made of. Each article is then sent to one of a plurality of destinations, such as recycling collection bins, according to the type of plastic. The method is particularly useful in separating PET and PVC used in containers, since these plastics are very difficult to sort by conventional methods. <IMAGE></p> |