Recycled plastics: Creating value from waste
The chemical sector is the largest industrial consumer of both oil and gas, currently accounting for 13 million barrels of oil and 305 billion cubic meters of gas per day. Even in its 2050 net-zero scenario, the IEA expects oil and gas consumption for chemicals to increase in absolute terms. Eventually, chemicals production will be the primary use of oil and gas given it is for non-combustion outcomes, the largest of which is plastics production.
Since plastics will continue to be essential for our future, we will have to step up our efforts to meet society’s resource stewardship expectations. The world produces over 300 million tons of plastic every year, but we are only recycling less than 20%. We are increasingly asking for sustainable products, being these recyclable, bio-based or at least, reusable. And the industry is answering this call with an ever-expanding variety of plastics recycling efforts across the world. But we must do more.
We have been mechanically recycling plastics since the 1980s but only thermoplastics can be recycled this way. Polyethylene (including HDPE, LLDPE/LDPE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC) and polyethylene terephthalate (PET) are the most widely used. They can be found in a variety of applications, from bottles and packaging to clothing. However, to recycle these mechanically, the waste stream must be clean, constituted of just one single plastic type and available in large quantities. When this is not possible, or to be able to recycle all other types of plastics, we need to use chemical recycling technologies.
Plastic producers are now embracing chemical recycling as a pathway to achieve their sustainability targets. Pyrolysis and gasification are technologies that allow a waste stream containing mixed plastics to be converted into an oil or syngas that can be easily processed in existing petrochemical plants. “The use of existing infrastructure is critical to reduce the overall cost of production of recycled materials,” says Tony Frencham, Group Senior Vice President, Chemicals and Fuels at Worley.
It appears that pyrolysis is gaining a larger momentum as the most direct route to produce circular polymers. The pyrolysis oil product, once treated, is sent to an existing cracker to produce olefins that are polymerized into typically HDPE, LLDPE, PE or PP. But we are also seeing producers selecting gasification as their preferred option to recover plastic waste.
“There are over 100 gasifiers in the world processing biomass and waste. Although their total capacity is small compared to solid and liquid fossil fuels gasifiers, this technology is considered commercially proven. This reduces some of the technical and commercial risks perceived by new players in this industry,” says Frencham.
But what if we sort plastic waste at the point of generation? “The majority of the cost to recycle waste is attributed to the collection and sorting of the materials,” says Angela Robledo, Group Director, Chemicals and Fuels at Worley.
“We could educate society to separate specific polymers, for example polystyrene, the same way that we keep glass separate from cardboard at home,” says Robledo. “We can then use depolymerization technologies that are tailored to single plastics. These technologies benefit from higher yields and operate at lower temperatures, therefore consuming less energy.
“We need additional investments from governments and organizations to support these initiatives and advance the readiness level of these technologies. But if we are able to collect large quantities of single polymers in a cost-efficient manner, depolymerization will be another pathway to balance other chemical recycling routes,” she adds.
So with an array of technologies to choose from and social licenses at stake, an opportunity presents itself for Arabian Gulf companies that export plastics to the rest of the world or have manufacturing investments abroad.
“We expect all plastics producers will be required by their major customers and, in turn, the final consumers, to be increasingly engaged in plastics recovery. They’ll have to meet end-market regulations impacting plastic waste such as Extended Producer Responsibility (EPR) policies,” says Frencham. Circular economy policies such as EPR policies are implemented in 26 markets today that together account for 88% of the world’s GDP. These cover landfill activities, recycling and focus on key materials such as plastic bags. They hold the producers of plastic products responsible for any negative environmental impact and hold them accountable for the associated costs.
A demanding society, market drivers and regulations have come together and created a new market, resulting in a number of chemical recycling plants commissioned or announced to date. The majority of these are considered first-of-their?-kind facilities as they will be proving completely new technologies, they’ll operate at large scale or they’ll be processing plastic waste instead of fossil-derived feedstocks.
An example of this is the newly formed joint venture between SABIC and Plastic Energy. Worley is providing EPCm services on the first advanced recycling unit in The Netherlands leveraging Plastic Energy’s patented pyrolysis technology. The plant will convert mixed plastic waste into a recycled oil called TACOIL that SABIC will process at its facilities to produce certified circular polymers as part of its TRUCIRCLETM portfolio of solutions.
In a world where net-zero targets are being adapted by an ever-increasing number of economies, plastic waste recovery projects will play an important role. We are building a cleaner, brighter future where we are utilizing plastic waste to create new products.
It has been estimated that global waste materials are worth USD 120 billion per year. So in addition to helping the environment and limit climate change, it is simply sensible to recover as much value from these materials as we can. After all, who would dump money in a landfill?
It is time to shift our mindsets and see waste as a valuable feedstock so that we can take it back into the circular economy to extract the true potential that it has.