Cracking the plastic crisis?
Only nine per cent of the plastic used around the world is recycled, the rest is buried, burned, sent abroad or lost to pollute land and sea.
Now an emerging industry promises to turn plastic waste into a valuable resource.
Chemical recycling breaks plastics down into basic components, which can then be used to make new products. It’s a theoretically endless cycle of processing and reuse, a so-called “circular economy”.
Backers claim the process can treat a wider spectrum of waste and produce higher quality material than conventional recovery methods.
One of a new breed of businesses testing the technology for commercial operations in the UK is targeting used tyres, which are typically made of 24 per cent plastic.
A company created by two friends who met while studying at university, Big Atom Advanced Recycling has built an imposing mechanical plant on a sprawling industrial estate in the petrochemical hub of Merseyside.
A contraption of conveyor belts and ferocious-looking steel bladed teeth is able to shred and separate the rubber, metal and textiles from one tonne of tyres every hour.
As co-founder Alex Guslisty explains, refining the mechanical process that pulverises old rubber is critical to the success of the all-important chemical separation further down the line.
“For that chemical recycling process to work well and be efficient, and for us to have good control of the products that are produced from that, we need to have good control of the feed stock that we put inside the reactor. We chose to process rubber, rubber coming from tyres.”
After testing on a small-scale laboratory rig, Big Atom has just taken delivery of a much larger reactor which will break down that rubber into its constituent parts of oil, carbon powder and gas, by heating it in the absence of oxygen. A thermochemical process called pyrolysis.
The company founders claim to have developed a method that uses lower temperatures, saving energy, while using the gas produced to generate electricity to power the reactor.
“This is a chemical process. It’s the bread and butter of what it is to be a chemical engineer. My background in oil and gas has helped me to be able to optimise this process in such a way that we can get more value and also have better environmental benefits,” says business partner Toby Moss.
The chemical part of Big Atom’s recycling process is still in development. For now, the rubber broken down from old tyres is being sold on for re-use in products like soft surfacing for sports and playgrounds.
But after further testing and tinkering to prove the viability and efficiency of the process and reactor design, Moss is confident that the company can commence commercial chemical recycling operations by the end of 2021, feeding recycled oil back into refineries, as an economical, environmentally sustainable alternative to virgin crude.
“We need to see more sites trialling this technology, and the infrastructure in place from the refining industry, as well as demand for circular economy products. All of those types of things will really help this market to grow, and for us to process all of our rubber and plastic waste locally in the UK, rather than abroad.”
The UK, like most developed nations, produces more waste than it can process at home, and sends much of it overseas. Before it banned the trade in 2018, China alone imported nearly eight million tonnes of plastic waste a year. Now the top destination for this waste is Southeast Asia.
That’s simply unacceptable to Adrian Griffiths, CEO and founder of another fledgling UK chemical recycling business, Recycling Technologies, based in Swindon.
“I think it’s a travesty really that actually in a modern society we actually call things recycled simply because we’ve put them on a ship and sent them overseas. No doubt some of that plastic will get recycled but the sad reality is that a lot of plastic does not get recycled and therefore is creating a problem for those places. Any civilised society should have to deal with its waste within the confines of its own country.”
To achieve that aim, the former automotive engineer has designed a commercial plant that can be put together in modular form, making it relatively easy to transport and put together anywhere in the world.
The machine processes films and laminated plastics such a crisp packets and yoghurt pots, breaking them down in another version of the pyrolytic process which produces a variety of waxes, oils and gas at the other end.
While some of that output could be burned in energy from waste plants, Griffiths is adamant that the future of chemical recycling lies in using the elements to create new products, rather than burning it and creating more climate-changing greenhouse gases.
“What we really want to do is take these materials back to the petrochemical industry and use them as the feed stock for making more plastic. You know the world has to get off the kick of burning anything with carbon in it, and so we want to make sure that plastic isn’t used just for fuel.”
Although in its infancy, chemical recycling has the potential, if widely rolled out, to reduce the amount of discarded plastic that ends up buried, incinerated or littering the world’s oceans.
Big chemical manufacturers such as Total, Saudi Arabia’s Sabic and BASF are throwing their weight behind chemical recycling initiatives, while investors are piling into start-ups in the nascent field.
Investments worth $4.3bn for projects to convert plastic rubbish into new polymers or fuel have been announced in the US alone since 2017, according to the American Chemistry Council.
The developments coincide with pledges by big consumer goods brands to slash the amount of “virgin” plastics, newly created from hydrocarbons, in their packaging.
To make a serious dent into the estimated 350 million tonnes of plastic churned out globally each year, though, chemical recycling will have to prove competitive during times of low crude prices. Cheaper oil and natural gas lower one of the main input costs for plastic.
Despite all of its potential benefits many chemical recycling doubters remain. With the petrochemicals industry planning to invest $400bn into new capacity over five years, according to climate think-tank Carbon Tracker, campaigners view these novel waste treatments as a distraction from the root of the problem: overproduction of packaging.
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