Enzymes enable infinite recycling

After taking part in an ideathon aimed at providing solutions for a plastics-free future, Paul Riley embarked on a year-long search for materials or technologies to solve this challenge. The answer he found ultimately resulted in a start-up called Samsara Eco.

In 2019, Paul Riley, an Australian businessman with experience in venture capital and private equity business building participated in a workshop with the CSIRO, a top research organisation in Australia; Woolworths Group, one of Australia’s biggest retail organisations; and several others on the topic of a plastics-free future.
It was the start of a new direction for Riley, said Ellen Burtenshaw-Davies, Chief of Staff for Samsara Eco during a recent interview with Sustainable Plastics. According to Burtenshaw-Davies, Riley then spent the following year exploring possible options and examining various technologies and their potential readiness for commercialisation that addressed this issue.  At a certain point, completely by chance, he came across an article about two chemistry PhD students at the Australian National University (ANU) in Canberra, who were working on the development of enzymes that could degrade plastic.

He contacted their supervisor and by December of 2020, Samsara Eco had been founded. The start-up, an initiative of Main Sequence (a venture capital fund founded by CSIRO, a federal government-backed research organization, to help commercialise research projects), the ANU, Woolworths Group and Paul Riley, launched with a team of just four people, including the two ANU students, Matthew Spence and Vanessa Vongsouthi, under the name Samsara.  In Sanskrit, Samsara literally means ‘flowing around’ or ‘world’, in reference to the cycle of life, death, rebirth and redeath – a fitting designation for a company developing technology for ‘infinite recycling’.

Fast forward
Over the next two years, the technology was further developed and expanded. The idea of using enzymes, said Burtenshaw-Davies, is quite obviously not new. Research teams -  in the UK and Japan, for example -  have also discovered enzymes able to degrade plastic; and they’ve been found in, among others, mushrooms, mealworms, and bacteria that degrade plastic  - but, she explained, “none of those will really be able to be adapted for commercial scale recycling or degradation, because they evolved naturally.”

The scientists at Samsara Eco have found ways to optimise these enzymes and are now aiming to commercialise the technology at scale within the short term. They have created a proprietary algorithm to design new-to-nature enzymes specific for different  types of plastics and specific for industrial processes that have a low carbon footprint, said Burtenshaw-Davies.
 “And they have been designed to be very efficient, so we don't need energy- or carbon-intensive preprocessing steps for the plastic that we recycle,” she said.

The first enzymes designed by Samsara were specifically targeted at PET/polyester and these have already been validated and patented. Currently, the company is working to expand its enzyme library further.  
“We will be announcing some new ones designed for plastics found in the packaging industry and in fashion and textiles, but also we are also looking beyond that, at other sectors, such as the automotive industry, as well,” said Burtenshaw-Davies.

Samsara Eco was able to focus on expanding its product portfolio due to the AU$6 million (about €3.83 million) the company raised in March 2022 in a funding round that was backed by the Clean Energy Finance Corporation (CEFC), along with Woolworths Group’s W23 venture capital and growth fund, and CSIRO’s Main Sequence Ventures.
The company has already attracted a few major companies as customers, for whom it will be recycling plastic at its precommercial facility. However, plans for a ramp-up to full commercial scale have already been announced. A new facility, which will probably be sited near Melbourne in Victoria and which will have a projected capacity of 20,000 tonnes, is scheduled to be operational from 2024. It will be Samsara’s first commercial scale facility -  but not the last: “Our goal is to recycle 1.5 million tonnes of plastic by 2030’, said Burtenshaw-Davies.
Funding for Samsara’s expansion comes from, among others, a successful Series A funding round in October of 2022, participated in by existing investors Main Sequence, Woolworths Group’s W23 and the Clean Energy Finance Corporation (CEFC), as well as new backers Breakthrough Victoria, Singapore’s Temasek, Assembly Climate Capital, DCVC and INP Capital in which the company raised some AU$56 million (about €34.8 million).

Enzymatic technology makes infinite recycling possible
Samsara Eco has developed the technology in an incredibly short span of time, and this has not gone unnoticed. In the brief two years of its existence, the company has won various awards, including  the Energy and Renewables category at the InnovationAus 2022 Awards for Excellence, where it also nabbed the title of Australian Hero; and the 2022 Banksia Foundation’s Ignite Award for a ‘technology that contributes to the development and well-being of human needs and institutions while respecting the world’s natural resources and regenerative capacity’.
The company’s proposition explains the enthusiasm: “Enzymatic technology means you can recycle plastic waste back to its original monomers, to create recycled plastic that is indistinguishable from virgin plastic, without fossil fuel feedstocks. This means we can stop depending on fossil fuel resources to make virgin quality plastic,” said Burtenshaw-Davies. “And we can do it at market recycled price, making it a feasible option for businesses.”

Price parity? How?
The depolymerisation process developed by Samsara is significantly faster than the processes developed by competitor companies, where degradation can take up to 24 hours. The enzymes can also be reused in a continuous process.
Samsara Eco offers another unique selling point compared to other chemical recycling technologies: the process has a low carbon footprint, unlike the resource and energy-intensive technologies that require large quantities of external heat and pressure.
“Part of the whole Samsara Eco agenda when it was first formed was the idea that there's no point in solving the plastic crisis if we're going to contribute to the climate crisis. Our mission is to deliver climate repair through infinite plastic recycling,” said Burtenshaw-Davies.
“The carbon in waste plastic will remain in the plastic economy with our technology. It's not being downcycled or taken out of circulation or released into the atmosphere. It enables us to sever our dependence on fossil fuels and virgin manufacturing.”
The company has done a life cycle assessment showing that the carbon footprint of its resins is significantly lower than for virgin plastic. It is not yet sharing the figures as the LCA still has to be peer reviewed. 

A platform technology
Recycling waste plastic, however, involves more than just breaking it down into its constituent monomers alone. Contamination, different types of plastic, different colours, additives -  how does the technology developed by Samsara handle these?
“Our technology recycles plastics that traditionally have low value, or no value, and are destined to go straight to landfill or incineration, including coloured or multilayered plastics, textiles and mixed blends of textiles,” said Burtenshaw-Davies. “Currently, we can separate out those additives and dispose of them responsibly. It may not be a perfect system, but it's a lot better than it all going to landfill. We can tap into plastic waste that is already on earth using infinite recycling to produce virgin grade monomers - and then keep them locked in circulation forever.”
The process itself will look something like a regular recycling line, she added, where what goes in is mixed plastic or shredded textiles that then gets processed; the difference is that what comes out are monomers rather than recyclate.

Samsara’s enzymatic technology is a platform technology, and the company looks to expand it’s technology to upcycle waste feedstocks to make green chemicals, decoupling the chemical industry from fossil fuel resources.

Keeping it affordable
The feedstock for the technology is consumer waste that is not suitable for mechanical recycling, said Burtenshaw-Davies. However, the company will not engage in waste collection and sorting activities. To ensure a constant supply of waste, Samsara plans to work with existing council collection schemes in which the waste goes to MRFs – municipal recycling facilities – and with Australian recyclers. “These recyclers separate mixed bales into single streams, and we can take the streams that the mechanical recyclers can’t use. By doing this we create value for what was previously waste”. Once the new facility starts up next year, the company will work with the recycling sector in Australia to arrive at a collaboration that works for everyone, Burtenshaw-Davies noted. “We’ll be looking for recyclers who can sell us the material we need at the right price,” she said.

She added that the reason the facility will be able to be built so quickly is because the ‘techno-economics’ make sense. Initially, when the process was invented, the decision was made to use existing equipment. “It didn’t have to necessarily be equipment specifically for recycling,” said Burtenshaw-Davies. “Our team took general equipment, reappropriated from other sectors and used it for this process. It's how we've kept it affordable, plus by repurposing existing equipment we've been able to scale fast.”

It also means that when parts break, these are easily replaced, because the equipment being used is validated and well established: “In other words, we're derisking the model as well, ”  said Burtenshaw-Davies.

Looking ahead
Although still young, Samsara’s ambitions already extend beyond Australia. The company, which expects to be profitable from its first commercial facility, plans to license the technology, enabling it to be rolled out internationally. 
The company currently has two business development managers who are exploring potential markets abroad. One is focusing on North America and Europe, the other on the APAC region.
“A lot of the decision-making in that respect is being guided by the legislation and mandates in the different regions,” said Burtenshaw-Davies. “It’s why we're looking at Europe as the first international start point. Europe has much stronger mandates; in addition, there are also feedstock options that makes it more sensible to start there.”
Meanwhile, she added, we’re out there talking about what we do and what we can do to make people aware that our technology can make a difference. “We can actually transition to a more sustainable plastics economy and to a circular plastics economy, but we need to create the right conditions to do so. There’s a lot that still needs to happen.”