Single-Use Plastic Recycling Solutions Are Emerging, But A Larger Problem Looms

The ocean plastic pollution crisis and the limits of plastic recycling ramped up to a new level in recent days, when a massive cargo ship burned and sank off the coast of Sri Lanka. It spilled tons of plastic pellets (as shown above) and toxic chemicals into the ocean, fouling local coastlines.

The disaster underscores the limits of recycling as a solution to the ocean plastic pollution problem. Whether plastic is recycled or not, transportation risks and hazards in the plastic industry will continue to increase alongside the growth of overseas shipping and the impacts of climate change.

Next-generation plastic recycling and the plastic crisis

To be clear, improving the global recycling rate is an essential element in a holistic solution to the ocean plastic crisis. Aside from derelict nets and other fishing gear, much of the plastic waste floating in the ocean consists of thrown-away bottles and other single-use plastic items that could be recycled.

Plastic recycling is supposed to rest on a value chain that motivates plastic users to manage their waste effectively. However, plastic has played a key role in the global economy for more than 50 years, and the recycling idea has yet to catch on. Only a small fraction is recycled.

Part of the difficulty lies in aggregating and cleaning used plastic items. In addition, recycling was not engineered into the chemistry of plastics at the onset, so recycling technology has to play catch-up. Typical recycling systems consist of melting or shredding, which yield a material that does not possess the superior qualities of virgin plastics. It still has some uses, but its application is mainly limited to downcycled materials.

Part of the solution involves reducing unnecessary plastic packaging, and progress is occurring in that area.

A more permanent solution involves developing new plastics that are tailor made to yield a high-quality result when recycled.

Here in the U.S., researchers at the Energy Department’s Lawrence Berkeley National Laboratory have been fine tuning a new, “infinitely recyclable plastic” called PDK for poly(diketoenamine). PDK can be recycled into high quality products that perform just as well as virgin plastic. In addition, the researchers have produced a study demonstrating that the PDK recycling process is less energy-intensive than conventional plastic recycling.

Another approach is to focus on bio-based materials that can be reclaimed as compost. They can also biodegrade harmlessly if lost or disposed improperly.

The conventional bio-based pathway could lead to conflicts over food and land use, so researchers are beginning to focus on agricultural waste and other non-food alternatives. In Canada, for example, researchers are deploying fish oil extracted from aquaculture waste to develop a bio-based form of polyurethane.

Kicking plastic recycling into high gear

Transitioning the global market to new, more sustainable plastics will take years. In the meantime, improving the technology for plastic recycling  could make a significant difference.

The emerging approach is to tackle recycling from the perspective of decomposition and reconstruction, rather than mechanical processes like shredding or melting.

That can be accomplished through biological means, as researchers have discovered that certain microbes and other creatures can digest plastic.

Chemical recycling is another area of interest. The process involves breaking waste plastic down into basic chemical building blocks, which can be reformed to yield new products. The newly reformed plastic can match, and potentially beat, virgin plastic on quality and performance.

The chemical recycling approach is rapidly catching on. Earlier this year, for example, Dow Chemicals formed a partnership with the company Mura Technology to scale up Mura’s HydroPRS chemistry-based plastic recycling system. As part of the venture, Dow will be the leading off taker for recycled plastics produced at Mura’s new U.K. plant.

Long distance shipping and plastic pollution

Another area of interest is the waste-to-energy field. While not ideal from a carbon emissions standpoint, a new generation of waste-to-energy technology is improving the process and shrinking emissions to a minimum.

Together, all of these pathways can help reduce the amount of mismanaged waste plastic that enters the sea from communities on land. However, as the Sri Lanka disaster demonstrates, waste mismanagement on shore is only one contributor to ocean pollution. The persistent growth of long distance shipping has already been linked to an increase in accidents resulting in lost cargo, and that will continue to offset gains achieved by improving the global recycling rate.

As measured by the number of containers lost at sea, shipping industry observers have reported a recent spike in cargo ship accidents that is concurrent with increases in traffic, speed and size, as well as an increase in severe and unpredictable weather related to climate change.

Cargo ship disasters that impact coastlines are all but certain to generate global news, but many take place far from the media spotlight. Despite the increase in accidents, the issue of lost cargo has received little ongoing media attention.

As one indicator of the lack of attention, the Sri Lanka disaster dominated the general news media for days when the ship lost its entire load of 1,486 containers, and yet it is hundreds of containers short of setting a record for losses of that kind. The worst cargo disaster in maritime history occurred just a few months earlier, last December, when the cargo ship ONE Apus lost at least 1,816 containers at sea in a heavy storm 1,600 northwest of Hawaii, far from coastal areas. The incident was covered in the trade press, but it barely flickered on general news channels, even though dozens of the lost containers carried items considered dangerous, including fireworks, batteries and liquid ethanol. 

The loss could have been worse. ONE Apus managed to limp to the Port of Los Angeles with approximately 1,000 more containers still on board, many of which were damaged.

Getting to the root of ocean plastic pollution

Whether or not plastic is shipped to or from a recycling facility, long distance shipping adds an element of risk and uncertainty to the fight against ocean plastic pollution.

The reusable trend could help reduce the volume of plastic feedstocks and plastic items shipped overseas if it also creates local systems that support reuse. The startup Loop, for example, has developed a model that relies on local pickup, processing and delivery of products in reusable containers.

The U.S. Department of Energy has also begun to focus more attention on lower-carbon technologies and systems that reduce the use of plastic. The effort also aims to make local waste systems more economical to operate domestically. That will also help contribute to a reduced need for overseas shipping while creating new local jobs.

Last month the agency unveiled a new $14 million round of funding for innovative solutions that focus on single-use plastics.

“Single-use plastics are the largest subset of plastics found in landfills and among the most challenging to recycle,” the agency explained. “Plastic production accounts for more than 3 percent of total U.S. energy consumption and uses roughly the same amount of oil around the world as the aviation industry. Yet, less than 10 percent of plastics are currently recycled, most of which are ‘downcycled,’ or repurposed into low-value products.”

The new round of funding builds on other recent initiatives such as the public-private REMADE (Reducing Embodied energy And Decreasing Emissions) Institute. The endeavor was launched in 2017 with the goal of reworking the entire plastics industry from the bottom up.

That is the kind of holistic, system-wide approach needed to achieve real progress in reducing ocean plastic pollution.

However, technology cannot be expected to do all the heavy lifting. The global economy slipped into a single-use, throwaway culture years ago. Getting billions of people to change their habits is a difficult undertaking, but a necessary one.

Image credits: Sören Funk/Unsplash