Article Source: IMechE
At Recycling Technologies we’ve developed a machine that converts any old plastic back into oil.
It’s the age-old process of thermal cracking, a technology repurposed – the same process that turns wood into charcoal, heating hydrocarbons in the absence of oxygen.
From a technical perspective, it has been done before, but most people that have done it have envisaged building refineries and taking the plastic to them. The problem with plastic is, because it’s low weight and low cost, it doesn’t transport very well. Our breakthrough is to reduce the capital costs by turning the technology into a machine, mass-producing it, and then taking the machine to where the problem is.
Trucks are already committed to taking stuff from people’s houses to a recycling centre, or materials recovery facility – we want to install machines at those facilities. Imagine six shipping containers. You can clip them together on site to form a 7,000-tonnes-per-year machine. One of the modules is doing the thermal cracking, one is generating the heat for that, and the other four are cooling it into fractions and cleaning it up.
Back to plastic
Our pre-production machine is a tenth of the scale of the final unit. It splits the product into four – wax, petrol, diesel and heavy fuel oil. We’re keeping the wax separate – there’s a shortage of wax in the world – and the other three we’ll combine to make a thick liquid. It’s not actually intended to be used as a fuel. The aim is to use it as the feedstock in a petrochemical facility – to turn it back into plastic again.
If you combine mechanical recycling with what we’re doing, which we call chemical recycling because you’re deconstructing the material back to molecules, then 90% of plastic is recyclable.
We’re about to move into a big building in Swindon, and eventually we’ll install our first unit at a site in Perthshire. The aim is to get to 200 machines a year, adding 1.4m tonnes of recycling capacity into the global system. Europe has 3m tonnes of capacity at the moment.
Cleaning the oceans
Because it’s exportable, we’re also looking at opportunities to set up these machines alongside the 10 rivers that carry 90% of the plastic that’s polluting the world’s oceans.
Because we process the plastic into something we can sell, it creates value for the material. If you can make it valuable on land, people don’t dispose of it in rivers and into the sea.