Contamination solutions and the future of ‘resilient recycling’

The 2023 Campus Race to Zero Waste is taking place at participating colleges and universities across the United States. As part of its program offering, the National Wildlife Federation and Lexington, Kentucky-based Rubicon Technologies Inc. hosted a webinar to discuss ways to address contamination in recycling streams on college campuses.

Emily Roberts, senior sustainability analyst at Rubicon, helps introduce circular solutions to customers looking to improve recycling operations. She said, “A big reason why [a strong and resilient recycling system] is important is so we’re able to make the shift from looking at waste as just waste—a byproduct of production and consumption—to a resource or a set of resources that are recirculated."

She said the shift especially is important in the United States where a large amount of single-use or disposable items are consumed. The Department of Interior announced in June last year that it would ban single-use plastic products and packaging on public lands by 2032. Beyond banning single-use products altogether, Roberts said, “Recycling is a really important part of this transition from a linear to a circular economy.”

Any number of factors contribute to contaminants making their way into recycling streams. Locations where consumers and employees use the same recycling bins, a lack of signage or instructions and time and space constraints all can lead to contamination.

The results can impact safety, material quality and even equipment longevity.

“It adds cost, time and confusion,” Roberts said. “That could be the cost of extra labor, extra equipment and confusion for all stakeholders. If I’m a consumer and I see a contaminant inside [a recycling bin], that may cause me to think, ‘Hey, actually maybe this type of plastic does go in here.’”

How to overcome?

Roberts said a few steps can be taken along the way to overcome some of the challenges caused by contamination. The first is tracking contamination at the point of collection, whether it’s a residential curbside bin or a dumpster at a grocery store.

“What’s important when we’re thinking about how to overcome this is really what is the [specific] contamination problem,” she said. “We need to define what specific problems are occurring, find a way to provide feedback on those, then see if that has an impact, whether that’s positive or negative.

While providing several technology-focused solutions, Roberts said contaminants also can be identified manually, such as with “a good old fashioned waste sort.”

But on the technology front, the first type of equipment Roberts said can be leveraged is a “smart bin”—a recycling bin that identifies, sorts and compresses material. She referenced the Bin-e smart waste bin as an example.

Poland-based Bin-e’s smart bin is designed for public places and armed with artificial intelligence (AI) to automatically sort and compress material, controlling the fill level while also providing data on the types of material it’s processing. The company provides an app for data management and that reports the technical status of the bin.

Currently, the bins are deployed in Europe, Asia and Australia.

“Obviously, a similar effect can be hopefully achieved with signage and training for people that are interacting with this bin,” Roberts said.

Another technology-based solution is bin sensors, which can be installed in commercial dumpsters and alert employees when a contaminant is identified.

“It takes data points at set intervals, then uses the camera,” Roberts said. “It can alert that employee, and that employee can remediate it before it’s picked up. They could send someone to get it or, if that’s unsafe, they can log that piece of information to see if it keeps happening and come up with a training or education program for employees or consumers at the location.”

Mobile apps also have been employed for recycling feedback at the point of collection, typically as it pertains to curbside recycling. In Europe, Oslo-based Carrot Tech developed software to collect data with the goal of motivating and incentivizing people and companies to improve recycling habits and take part in the circular economy.

Carrot Tech’s app gives an overview of the amount of waste generated per household and the developments and changes over time.

“Those users can see the impact of their actions over time,” Roberts said. “They can see their history of what types of solid waste they have generated [and] recycled, [and] a similar feedback mechanism could be used on a college campus or at a smaller scale to really give feedback to the consumer on what the impact of their actions has been over time.

“I think this is a good example of an education or feedback tool that could hopefully be implemented before the point of collection or at the point of collection to educate consumers on what they can [recycle] and what would end up being a contaminant,” she added.

The Recycling Partnership (TRP), Washington, also developed a real-time interactive “chatbot” that answers consumers’ questions about what’s recyclable in their respective communities. The service currently is offered through TRP’s website as a beta version.

Rubicon provides its own technology-based tracking and feedback platform. The RUBICONSmartCity technology suite designed for waste and recycling fleets offers contamination identification and recording as well as service verification of collection, driver behavior metrics, real-time route progress data and operational insights.

“The idea is that it’s taking a picture of all the waste going into that hopper … [and] identifying things that shouldn’t be there … and allowing the public works team to see that information and aggregate it over time,” Roberts said of Rubicon’s technology.

Currently, she said RUBICONSmartCity technology cannot specify compostable bags from any other type of plastic bag but added that companies are working on refining their technology to address what she said is a unique issue.

A low-tech option to communicate at the point of sale, Roberts added, is using How2Recycle labels on the products themselves, giving the consumer information on how to best recycle that item.

Product design has a part to play in reducing contamination, too.

A well-functioning recycling system starts from the beginning with product design, Roberts said. During that phase, designers should be thinking about how consumer products and packaging can be recycled as well as ways to reduce confusion.

“Recycling really works best when producers of new products and packaging really design with recyclability in mind,” she said.

The 2023 Campus Race to Zero Waste results for the diversion, per-capita recycling and food organics categories can be found here, while the final results will be revealed in April.