Plastic waste management - collaboration is key

UK-based Greenback Recycling Technologies (Greenback) has developed a chemical recycling approach that is based on decentralised small-scale modular units designed for local use. The first plant recently went into operation in Mexico and the second is planned, this time supported by the Alliance to End Plastic Waste. Sustainable Plastics talked with Philippe von Stauffenberg, CEO and founder of Greenback, and Nicholas Kolesch, the Alliance’s vice president of Projects about the collaboration between the two.

There have been, over the past two years, a great many announcements of projects and plans for new chemical recycling facilities. There are far fewer that are able to report having actually built and taken a plant into operation.

One company that has now successfully done so is Greenback. Founded in 2018 by Philippe von Stauffenberg, Greenback opened its first fully commercial-scale recycling plant in May of this year. The plant is a lighthouse project undertaken in collaboration with, and partially financed by, Nestlé Mexico, in Cuautla, Mexico. The partners are constructing a second unit at the same location, to increase capacity up to the 6,000 tonnes projected for the site. A single module can process around 2,800 tonnes and can be scaled up incrementally as needed. The Alliance to End Plastic Waste is providing funding for this second module.

“We just signed the agreement and we're looking forward to seeing it installed at the same facility, sometime within the next 12 months,” said Nicholas Kolesch, vice president of Projects at the AEPW.
Or sooner, according to Greenback CEO Philippe von Stauffenberg. “We should be able to get the modules built within nine months and then installed. We hope to be ready for commissioning sometime before June of next year,” he said.

Technology
“Greenback’s approach is very interesting,” said Kolesch. “It's a very cost-effective technology to get to pyrolysis oil and then, hopefully, to food-grade plastics. What we've seen in our relationship over the last few years is, first of all, the development of the pilot facility in the UK, with which we were quite impressed. Subsequently, we saw also the unit that has now been opened in Mexico. The great thing about this technology is that it's modular, so you can line up one unit beside the other and increase the uptake of plastic waste and the capacity of the facility overall,” he added.

It also allows a broader base of feedstock to be used. Greenback’s modular units make use of a microwave-induced pyrolysis process developed by Enval, originally a spin-out from the University of Cambridge, and now owned by Greenback. The technology, developed specifically for recovering materials from foil-laminated flexible packaging and can handle a wide variety of complex plastic packaging, uses microwave energy to break down plastics into solid, liquid, and gaseous components. The gas is funnelled back into the system and used for power generation, minimising overall CO2 emissions and energy use. According to von Stauffenberg, this microwave system is the only one in the world that can separate plastic aluminium laminates into low-carbon-cost aluminium and pyrolysis oil. “A Tetra Pak, for example, will usually have an aluminium stratum, which we can then recover,” he noted.

The process is therefore a very efficient one that can take a wide array of materials.  “The system can take a higher amount of PET and a higher amount of the types of oxygenated barriers used in flexible plastics these days. We can use, say 30% of material  that other pyrolysis processes can't use, because of the Enval pyrolysis technology. Why is that important? Because the sorting can be less rigorous, which means lower costs,  and more types of waste can be processed in the system,” he explained.

The process produces pyrolysis oil that ideally is intended to be used to create new, food-grade plastics. This is something Greenback is setting up in cooperation with the petrochemical industry’, he pointed out. The company is talking with players in that industry to ensure the pyrolysis oil Greenback produces, ‘makes it into the cracker’, and how to handle the different pyrolysis oil fractions.

“The quantities are still quite small,” he pointed out, “but once in the cracker, that content can be allocated via the mass balance method to the plastics created.” In the future, it may be possible to produce enough pyrolysis oil for a dedicated cracker in order to be able to make 100% recycled content plastic, he said. Nor is refining the pyrolysis oil into a naphtha-quality feedstock a current goal.

“Strategically, what we need to do is build more capacity to make pyrolysis oil and not try to get the pyrolysis oil to a stage where it's exactly like naphtha. It's more difficult to actually build the capacity. So, let's get that done first,” said von Stauffenberg.

Partnerships are essential
It is clear that the kinds and scale of initiatives that Greenback is pursuing require collaboration with different partners across the board. Greenback has also tackled aspects such as ensuring a feedstock supply, building offtake relationships, and securing funding.

The latter can be especially challenging, said von Stauffenberg, as, obviously, investors want to make money. “It's a really difficult environment to raise money in, so we're very fortunate to have the Alliance helping us” he said.

According to Kolesch, for the AEPW, what was particularly attractive about the project was the combination of activities yielding the kind of holistic solution the organization looks for. He explained: “The facility is located on a landfill. There is a material recovery facility - near the landfill, next to which Greenback’s recycling plant has been installed. This effectively creates a perfect chain: the collected waste materials are brought to the landfill, taken into the recovery facility and separated into streams suitable for recycling. The output is -  as Philippe has described  - the different fractions of pyrolysis oil that can be used, as well as the aluminium that can then be sold on.”

The role of the AEPW
As a 501(c)(3) organisation, the Alliance to End Plastic Waste is a non-profit with a dedicated mission – to test and prove new ideas that will create a circular economy for plastic. The Alliance can enable companies like Greenback to be successful by providing capital – usually in the form of grants or concessional-rate loans -  to help to derisk the investment  - “and we can bring technical expertise and knowledge to the table through our team and also through our member companies,” said Kolesch. “So that's a huge part of our mission: to develop, derisk and deploy the solutions that are out there.”

The Alliance is now active in more than 20 countries around the world with more than 50 projects. Its goal is to end plastic waste in the environment and to support that mission through collection activities -  where everything starts.

“Some of our projects have already that collection element dealt with, but others do not, especially those targeting communities in the more developing countries in the Global South,” said Kolesch.

In those cases, the AEPW invests time and effort on helping communities first to put collection systems in place, to establish the feedstock stream needed for recycling, and then bringing the material recovery facilities online that enable good quality bales of recycled recyclable material to be made available. 

“Greenback’s technology is a compelling solution because it's modular and could be implemented anywhere. If we're organising a collection programme, it is something that could therefore easily be brought on site and installed downstream of the collection system that we have fostered in a community,” he elaborated. “It can be fully manufactured off site, transported to the site and assembled there.”

He noted that larger scale pyrolysis technologies are ‘very much something that must be built in situ’ -  and typically, for these to be cost effective, they need to be built at scale.

“We are still waiting to see these large-scale facilities come on stream and be proven in reality,” he said. “I think what we've seen with Greenback in the economics is definitely something that's better than a lot of the other technologies that we've come across thus far. One of the limitations is of course that, at a certain point, there are economies of scale to be gained on larger-scale technologies. But at this stage, we are quite pleased with approach Greenback has taken with its technology and with how it has been able to transform this into reality.”

Trust and traceability
Another valuable aspect of Greenback’s approach is the fact that it has developed a system called eco₂Veritas™ to provide complete traceability of the entire collection and recycling process. It is an essential element in the entire process, emphasised von Stauffenberg. He explained that the pyrolysis oil produced is very similar to naphtha but is sold at a significant premium above the current market price. “Plus, demand is high and growing fast. There is a risk of fraud in the market, as it would be easy to mix fossil naphtha into the oil and pass it off as pure pyrolysis oil. We need to make absolutely sure that if we say something has recycled content, that it is true – whether it is chemically or mechanically recycled – as otherwise, the industry value chain will lose credibility and consumer trust.”

eco₂Veritas™ is a blockchain-based system that offers complete transparency, certification and traceability throughout the entire circular value chain. “So, we can prove that our claims are true,” he stressed.

And it has also enabled a further step, he added, relating to the collection systems Kolesch referred to previously.

“Greenback had already signed an agreement with Nestlé, but we’ve now signed another one to be announced soon. They will pay us to collect - on their behalf – an amount of waste that is equivalent to the tonnage of waste that they put into the market as packaging; in other words, a voluntary extended producer responsibility arrangement. We then provide them with certificates through eco₂Veritas,” he explained. It is a model that he is intent on expanding to many more brand owners.

Greenback must not only be able to prove that it is truly waste that is coming in and that the volume is equivalent to the volume of packaging that the companies have produced. It must also demonstrate that its collection system is fair, inclusive, and equitable in terms of the wages paid to the waste pickers and that no child labour is used. “We use smart contracts to pay the collectors objectively according to the quality and volume of the waste they bring us. The real point is that it is one thing to have the physical technology, but it is still really important to create a market for the flexible plastics that otherwise wouldn't find its way into the recycling system.”

Right now, the higher value plastics are finding their way into the recycling market, while the lower value plastics - the multilayer packaging, the flexibles, the various films -  are more difficult to get into end markets.

Kolesch: “So, if we can foster that demand through technologies like Greenback’s, we're going to be able to gain a lot more volume from the systems that are already in place, whether they're formal or informal systems. After all, if that flexible material is being collected, it's going into landfill or incineration. If it's not, then obviously, it's accumulating in the environment. And that’s problematic.”

Future plans
With the first commercial plant now up and running, Greenback has plans to instal more plants in other parts of Mexico, North and Latin America, and then Africa, Asia and Europe. Von Stauffenberg aims to establish a decentralised network of collection and recycling plants near sources of post-consumer plastic waste worldwide to produce recycled feedstocks suitable for the petrochemical and plastics industry value chain to close the loop.
And this is what the AEPW wants to enable, by providing the support and credibility needed to realise these ambitions.
“We aim for these kinds of holistic solutions, where it's not just one piece of the puzzle, but, like this project in Mexico, several pieces of the puzzle, all in one,” said Kolesch. “These are the projects that enable us to advance and scale innovative solutions for the circularity of plastics worldwide.”