Each week, Ridwell workers fan neighborhoods in six cities around the country picking up canvas sacks stuffed with plastic bags and packing waste. The plastic film is sorted and sent to Nevada where it’s recycled into Trex decking. Each year, the environmental startup diverts 500,000 pounds of the plastic waste for recycling in the Seattle area alone.
That’s an ideal scenario for a plastic item’s end-of-life.
What happens with most of the world’s plastic trash is grim. In the U.S., about 5% of plastic waste is recycled. Most of the rest winds up in landfills or the environment. About 12 million metric tons of plastic lands in the ocean each year, according to Greenpeace.
And the numbers are getting worse. The amount of plastic that’s tossed annually by Americans increased by 40% from 2000 to 2018, reported USAFacts.
Well-intended consumers are caught in the middle, unsure of what can be recycled, what happens to their chucked water bottles, and what’s being done to address what some are calling a “plastic waste crisis.”
“Putting the burden on the consumer is part of the problem,” said Lucas Ellis, an assistant professor at Oregon State University’s School of Chemical, Biological and Environmental Engineering.
Despite being an expert on plastic recycling with a chemical engineering Ph.D., Ellis admits that even he has “a hard time tracking what is or is not recyclable.”
Now startups, scientists, and government leaders and agencies — including many based in the Pacific Northwest — are taking more aggressive steps to address the avalanche of plastic waste that was triggered in the 1970s and has surged over the decades.
- Municipal waste collectors and companies like Ridwell are recycling plastics, educating consumers and strengthening the market for U.S. end-users of the waste.
- Researchers are innovating ways to efficiently break down plastics — the vast majority of which are made from fossil fuels — into reusable materials including jet fuel or additives for strengthening concrete.
- Activist and government efforts aim to reduce new plastic production and put more of the waste responsibility on manufacturers.
But it remains a difficult dilemma for those working on the problem. Not all waste that can be recycled is recycled, and many plastics are too costly and chemically difficult to reuse.
“Recycling is not enough to solve the plastic pollution crisis,” said McKenna Morrigan, Seattle Public Utilities’ strategic advisor for Waste Prevention and Product Stewardship.
Recycle or landfill?
Seattle Public Utilities, which provides solid waste services for 700,000 customers in Seattle, recycles a wide variety of plastic consumer goods. But there are limits.
The city can recycle plastic bottles, jugs and yogurt containers; lids 3 inches or larger; clean plant pots; toys; buckets; and similar items. Goods destined for the landfill include any dirty plastics; inflatable pools; CD and DVD cases; shower curtains; tarps; and other plastic and vinyl waste.
Seattle customers are pretty good recyclers overall: Roughly 80% of all plastics collected can be recycled while 20% are “contaminants” — meaning they’re the wrong kind of plastic or are the right kind but are dirty with food or mold, the city reports.
“Our program has among the best outcomes of any recycling program in the country,” Morrigan said.
Still, there are significant challenges. For example, the utility had to stop collecting plastic bags in 2020 because loose bags were jamming up the sorting equipment. That includes the plastic air pillows and plastic envelopes often used for shipping by Amazon — a company whose plastic use is on the rise.
The Seattle-based retail giant is estimated to have produced 709 million pounds of plastic packaging waste last year, according to a new report from Oceana. That’s an 18% increase over the previous year. Before the report’s release, Amazon posted a blog claiming a much smaller volume of packaging waste, and sharing its strategies for reducing that amount.
New plastics, new challenges
So what do you do with all those grocery and dry cleaning bags and deflated air pillows? In the absence of municipal collection, consumers can find a free drop-off site or pay a company like Ridwell to collect them.
Ridwell is successful in recycling the film because it’s separately bagged, which avoids the need for sorting by machines that can get gummed up. And the customers generally follow instructions to only recycle material that’s clean and dry, said Ridwell spokesman Caleb Weaver.
But even with their simplified process there are hurdles.
Manufacturers are increasingly using a newer type of packaging called multi-layer plastics. They’re used for thicker, free standing bags like the ones that package Craisins, pet treats and other foods, as well as chips and granola bags that have a foil lining. They require a different, less common recycling process than is used for plastic film.
“That is a category of plastic materials that is virtually impossible for a household to get recycled,” Weaver said.
Ridwell recently found two Los Angeles-based companies willing to take these plastics. One turns them into a faux gravel that’s used for landscape drainage and another is producing an alternative to cinder blocks. These are new efforts with limited capacity.
“It’s not a stable market that a lot of the large trash haulers could use to sell that material in a secondary market, even if they could get past the contamination issues and sorting issues,” Weaver said.
Part of Ridwell’s mission is to educate customers about waste, Weaver said, so they can choose to avoid goods that are hard to recycle.
Turning plastic back into plastic
The growing stream of plastic waste is being tackled at the international level as well. Earlier this month, United Nations negotiators met to discuss an upcoming plastics pollution treaty. The effort aims to reduce plastics use and could potentially put a limit on new plastic production. A ban like that would require better options for turning waste plastic back into plastic, which is a challenge that OSU’s Ellis is tackling.
Ellis helped develop an innovative new strategy for processing waste plastics that can make use of mixed plastics — potentially making it easier for consumers to recycle their waste. It also employs readily available chemical reagents and doesn’t use super high temperatures required by some other processes.
The plastic waste undergoes chemical treatment that turns it into a solution fed to genetically modified bacteria. The bacteria convert it into compounds that can serve as the building blocks for manufacturing new plastics.
Ellis and colleagues published their research this fall in the esteemed journal Science.
Their strategy to effectively combine chemical and biological process “is what was really novel,” said Ellis, who worked on the project while at Colorado’s National Renewable Energy Laboratory before taking a role at OSU.
The process can be tweaked to optimize for different waste streams and end products. Ellis said it’s “opening a floodgate” of uses.
At Washington State University, scientists are employing different engineering approaches to turn plastics into aviation fuel and to recycle the polypropylene or polyester fabric that’s used in disposable masks into an ingredient that strengthens concrete.
But even with cities like Seattle and companies such as Ridwell supporting recycling, and university researchers discovering clever ways to reuse some of the waste, experts agree it’s not enough. The volume of plastic being generated needs to shrink and the products need to be designed with recycling in mind, they say.
That will require a system-wide approach where manufacturers play a role in solving the problem, said Ellis, who added, “we need to think about what the lifecycle of the materials will be.”
Editors note: Seattle Public Utilities provides solid waste services for 700,000 customers, and water for 1.5 million. This article has been updated to correct the solid waste number.