There are many different types of plastics and the proper procedure for recycling varies. It is therefore important that the plastic is sorted correctly before it is recycled. There are machines that can handle the sorting, but they are expensive and complicated. In poorer countries, sorting is often done by hand instead.
The problem is that it can be difficult to know what type of plastic it is by just looking at a plastic package. Now an invention that just won this year's James Dyson Award could make this process easier.
The invention consists of a small hand scanner that can distinguish between many different types of plastics and tells the sorter how each piece of packaging should be sorted. The scanner uses infrared spectroscopy to distinguish the type of plastic.
Normally, infrared spectroscopy is a relatively expensive technology, but inventor Jerry de Vos, at TU Delft in the Netherlands, uses discrete infrared spectroscopy. The method is not quite as accurate, but it is good enough to identify most types of plastic used in packaging.
The scanner is based on cheap components and the instructions on how to build it are readily available to anyone for free. So far, Jerry de Vos has only built one prototype, but the plan is to also sell cheap kits with all components. In this way, he expects to be able to keep the price down so that even sorting companies in poor countries can afford the scanner.