Unpacking of food waste | Vermont Business Magazine


Kate Porterfield, a graduate student at the University of Vermont, tests unwrapped food waste for microplastic contamination. His research, funded by Casella, examines the sustainable use of this waste for biogas production and to improve resource recycling in Vermont. (Photo / s: Sarah Hobson, Kate Porterfield)

UVM researchers are teaming up with Casella to discover the relevance of packaged food waste for recycling organic materials.

Vermont Business Magazine More than a third of food waste in Vermont is still packaged, a tricky situation when it comes to mandatory food waste diversion from landfills under the state’s new universal recycling law. Law 148 banned food waste from landfills from July 2020.

Researchers from the University of Vermont (UVM) have partnered with Casella Waste Systems to test the effectiveness of a new deconditioning system at the company’s recycling facility in Williston.

“It’s very exciting for us to bring this technology to our home country,” said John W. Casella, President and CEO of Casella Waste Systems, Inc. “This facility will allow us to separate organic raw materials. and recyclable valuable waste, put to a higher and better use, and to preserve natural resources.

Casella funded a pair of UVM graduate students to conduct this research on sustainable waste management. Assistant Professor Eric Roy and two of his graduate students are determining whether food waste, once separated from its packaging, can be used for anaerobic digestion and composting.

As an alternative to composting, food scraps, often in combination with dairy manure, are broken down by microorganisms in the oxygen-free containment of an anaerobic digester. The process produces biogas, a clean, renewable energy source. With biogas, anaerobic digestion produces liquid and solid digestates, usually spread on agricultural fields as fertilizer, used for animal bedding or compost.

But what if the separated food waste still contains small packaging particles, mostly plastics? The maker of the deconditioner claims 95 to 99 percent efficiency in isolating food from its containers. This leaves a small fraction of microplastics that can find their way into the environment when food waste is incorporated into the soil as digestate or compost.

“Casella is very proactive in determining how well their deconditioning facility is working to maximize environmental benefits and minimize costs,” said Roy, UVM faculty member at both the Rubenstein School of Environment and Natural Resources and the College of Engineering and Mathematical Sciences. (CEMS). “We are trying to establish data that can guide the management of food waste in Vermont and beyond.”

Casella and the researchers focus on two main streams of packaged food waste: pre-consumer (typically large amounts of packaged, but unsaleable, products from food manufacturers) and post-consumer, which may contain packaging or packaging. other contaminating materials. Roy and his students test the two unpacked food waste streams. They quantify its value for biogas production and composting and its plastic contamination.

“I was able to sit down with people from Casella and come up with research questions through dialogue about our mutual concerns and interests in the environment and waste management,” said Kate Porterfield, PhD student at CEMS, who assesses the relevance of packaged food waste destined for biogas production.

Porterfield began researching the facility in January 2021, the day Casella made her first load into the deconditioner. She watched as operators load packaged food waste into the hopper, where rotating pallets opened the package without breaking it. The separated food waste was passed through sieves and the packaging was removed for recycling or sent to landfill. Porterfield collected food waste samples after the separation process for laboratory testing.

Casella’s support has enabled Porterfield and Roy to develop new ways to measure plastics in food waste. Porterfield is working on methods to quickly and easily isolate and quantify the abundance of microplastics. Marine scientists are doing similar work to study plastics in the oceans.

Porterfield uses an instrument called the Automated Methane Potential Testing System (AMPTS 2), a lab-scale anaerobic digester that runs 15 soft drink-sized food waste sample bottles at a time. Every time a sample creates methane, a computer records the gas bubbles and creates a graph of biogas production. This helps researchers determine how efficiently food waste can be turned into biogas.

Once the organic waste has been digested, tiny pieces of plastic can be easily removed using a fine mesh sieve. Porterfield counts the particles under a microscope to see how much plastic is contaminating the organic material. She then uses Fourier Transform Infrared Spectroscopy (FTIR) to classify plastic polymers isolated from the laboratory digestion process.

“Once we have identified the types and amounts of contaminating plastic, Casella and others in the industry can go back upstream to food manufacturers or waste suppliers to look for ways to dispose of the packaging. unwanted or other contaminating material, ”Roy said.

“Our results are extremely important to the Vermont Universal Recycling Act which required this type of research,” Porterfield said. “There is so much we don’t know about the use of food waste, especially the impacts of plastic contamination. “

Sarah Hobson, a master’s student at UVM, will study unwrapped food waste, composting and plastic contamination. She began her two-year study program at Rubenstein School this fall with a Sustainable Materials Management Scholarship funded by Casella.

“Can compost containing microplastics be used safely in the environment?” Hobson said. “This is still a new area of ​​study, and we are trying to better understand the life cycle of plastic in food waste.”

“We are proud to work with a leading sustainable development institution like UVM and to provide UVM students with meaningful research opportunities that will advance our industry,” said Casella. “Seeing research have a practical effect in real time is very powerful, and we are grateful for the ongoing partnership and shared commitment of UVM in promoting environmentally sustainable solutions.”

To help guide his work, Hobson will use participatory action research to learn firsthand from farmers, compost producers and residential compost users what they know and what questions they have about plastics in food waste. and compost.

Roy and his graduate students bring their research to the classroom to engage up to 50 undergraduates each year in projects that become essays.

“Students are excited when they realize that they are on the frontier of new knowledge and that they are involved in actionable science that will be used to improve the environment,” Roy said.

In Roy’s advanced ecological design course last spring, a team of undergraduates conducted anaerobic digestion experiments using unwrapped food waste and developed methods for the separation of microplastics.

“Working with Kate Porterfield and my group has been by far the most fun, high-level learning project I’ve ever been on,” said Garrett Dunn, UVM undergraduate. “The most important aspect was how we decided to work on a relatively new research discipline in waste management. It really made the learning experience very unique compared to any other class.

This fall, a larger group of students will learn about the carbon cycle and food waste management using similar experiences in Roy’s Green Design and Living Technologies course. These hands-on learning experiences take place in a new eco-design creation space at the Aiken center on the UVM campus with the support of Casella.

About the University of Vermont

Since 1791, the University of Vermont has strived to advance humanity. The strengths of UVM correspond to the most pressing needs of our time: the health of our societies and the health of our environment. Our size, large enough to offer a wide range of ideas, resources and opportunities, yet intimate enough to allow close mentorship between faculty and students at all levels of study, allows us to pursue these interconnected issues through interdisciplinary research and collaboration. Providing an unparalleled educational experience for our students and ensuring their success is at the heart of our activities. As one of the nation’s premier land granting universities, UVM advances Vermont and society at large through the discovery and application of new knowledge.

UVM is derived from Latin Universitas Viridis Montis (in English, University of the Green Mountains).

Learn more about Casella, a regional solid waste, recycling and resource management services company based in Rutland, Vermont.

Video describing the Casella unboxing facility in Williston and the research partnership between Casella, the University of Vermont and local food manufacturers

You can also see it here: https://youtu.be/0qFhQe9frgM

Source: BURLINGTON, Vermont – UVM 10.15.2021


Check Also

Early rubbish collection in Brisbane sparks petition but ultimately shot down by council

Brisbane City Council has rejected a petition calling on it to ensure refuse collection trucks …

Leave a Reply

Your email address will not be published.