Same As New
A research team at the Chalmers University of Technology, Sweden, created a new process for breaking down plastics waste. The method breaks down any plastic to a molecular level. The plastics break down into gases that can then be converted into new plastics of equal quality to the original. The process is efficient and can be implemented within the framework of today’s existing infrastructure. It has the potential to transform any current plastic factory into a recycling refinery. Furthermore, it is applicable to any plastic waste, even old plastics that have been sitting in a landfill or floating out at sea.
Henrik Thunman, Professor of Energy Technology and leader of the group, doesn’t see plastic as a bad thing. He considers the material to be a resilient asset. While most of the world is turned upside down by the fact that plastics don’t break down, he is not. Thunman says the fact that they don’t degrade makes them perfect for circular usage. There is immense value in used plastic, and people should be motivated to collect it because of that. Thunman said:
Circular use would help give used plastics a true value, and thus an economic impetus for collecting it anywhere on earth. In turn, this would help minimise release of plastic into nature, and create a market for collection of plastic that has already polluted the natural environment. We should not forget that plastic is a fantastic material – it gives us products that we could otherwise only dream of. The problem is that it is manufactured at such low cost, that it has been cheaper to produce new plastics from oil and fossil gas than from reusing plastic waste.
Steam Cracking
The researchers diligently experimented with chemical recovery by way of steam cracking of plastic. Finally, they established an adept process that can turn used plastics into plastics of virgin quality. The research has been published in the journal Sustainable Materials and Technologies. Thunman explained:
Through finding the right temperature – which is around 850 degrees Celsius – and the right heating rate and residence time, we have been able to demonstrate the proposed method at a scale where we turn 200 kg of plastic waste an hour into a useful gas mixture. That can then be recycled at the molecular level to become new plastic materials of virgin quality.
Waste Hierarchy
The way plastic is recycled now involves the material being degraded over and over until it’s of such low quality that after being recycled a few times it’s just burned for energy. The process is called ‘waste hierarchy.’
Only 8% of recyclable plastics are recycled into plastics of lower quality – which then gets recycled again into plastic of even lower quality. The process continues until the plastic is useless and thus incinerated, which releases carbon dioxide into the atmosphere. Thunman said:
“Instead of this, we focused on capturing the carbon atoms from the collected plastic and using them to create new plastic of original quality – that is, back to the top of the waste hierarchy, creating real circularity.”
Future Plans
The group’s initial trials went well, and now they have moved on to demonstrating the feasibility of their process. After that, they plan to scale up the process to be able to process hundreds of tons of plastic waste every day.
