A simple plastic scanner
Recycling is becoming more important, both to ensure that we don’t waste materials but also to ensure that we don’t end up with waste where it shouldn’t be, like plastics getting into the ocean. But one issue recyclers face is dealing with all the different kinds of plastics we have. A bin bag is made from a quite different material from a fizzy drink bottle, so they have to be recycled separately. But if you don’t know what things are made of, how do you begin? In the developed world, we have big plants that can sort through all our rubbish, but in the developing world, they need a quick, straightforward way to tell one plastic from another. And tech startup Matoha Ultrascience has built a portable machine that makes this sorting process quick and simple. Adam Murphy heard how it works from co-inventor Martin Holicky...
Martin - Our machine has infrared lamps and infrared optics in there and every material has a unique infrared signature. So we just put the item of plastic or textiles in it and within two seconds it tells you immediately what material it is, so far example if it's cotton, polyester or similar materials.
Adam - How does it get that fingerprint? What happens to the infrared light to generate this signal?
Martin - Infrared light interacts with the material so it gets reflected off the material and absorbed by the material. And then our optics look at which parts of the infrared light have been absorbed and from that we can deduce what the material is.
Adam - And where do you see this working? What do you think the applications are?
Martin - It's really important for any kind of recycling of both fabrics and plastics to know what's the material composition. So you need before any kind of recycling you need to sort the waste coming in. So our machine could clearly be useful for sorting of plastics, all kinds of waste so that you can then recycle them.
Adam - How specific is it? How many different kinds of plastics can you identify?
Martin - We can identify all the major types; polypropylene, PET, polystyrene, all the major types and the accuracy is quite good actually. You just put it there and it can immediately tell you what it is.
Adam - Are you hoping to go on someone’s countertop or is it for other locations?
Martin - Currently in the developed world they have this super expensive big machines which can sort the waste automatically, but because it's so expensive in the developing countries they can't afford them. So what we envisage is that we give the workers in the developing countries almost an additional pair of eyes. It can tell you what the material is and then they can sort it properly.
Adam - Now some plastics are see-through and others are not, like polystyrene is solid white, how do you deal with the two different kinds?
Martin - So we have actually two lamps in there – one shines from the bottom, one shines through the sample and depending on if the material is transparent or not the lamp of the particular kind makes the infrared light go through or reflects off the sample.
Adam - How easy is it to use?
Martin - Well it's super easy. You just put it there - you don't need a degree in chemistry or physics or anything like that. Just put it there and it tells you immediately what it is. It's like a supermarket checkout - beep, beep, beep.
Adam - And is this ready to roll out, or are you at the prototype stage or how far down the line are you?
Martin - We have been working on this for the past two years and currently we are doing the first field trials in Europe. We are nearly there and hopefully later this year we'll be able to start selling the machine.