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New recycling solution tackles greasy pizza boxes

Each day, roughly 43 million Americans indulge in at least one slice of pizza, contributing an impressive $47 billion annually to the U.S. economy. A significant portion of these pizzas arrives in corrugated cardboard boxes, posing a notable challenge for waste management due to their contamination with fats, oils, and greases (FOGs). Therefore, recycling pizza boxes is essential.

Unfortunately, the contaminants make pizza boxes a recycling nightmare. Delicious, cheesy slices leave a greasy residue that renders the pizza boxes unsuitable for traditional recycling processes.

Compounds like peanut butter and pizza box grease are also incredibly difficult to clean off, essentially relegating many of these boxes to landfills.

Recycling pizza boxes

Researchers at Idaho National Laboratory (INL) have embarked on a mission to change this. Consequently, they’ve developed a new method to decontaminate cardboard, which could revolutionize recycling practices for food containers.

Their latest publication in the Journal of Cleaner Production details this breakthrough, highlighting a process that uses material separation capabilities to address the issue.

“To make specific separations possible, we need to first prove the overall concept of material separations, which is what this study accomplished,” explained Aaron Wilson, the principal investigator for this project.

Dimethyl ether for pizza box recycling

The heart of their experiment lies in the use of dimethyl ether (DME), a green solvent known for its use in refrigeration. The team designed a system with two vertical stainless-steel reactors to facilitate the extraction and separation of FOGs from contaminated cardboard.

The process begins by mixing broken-down cardboard pieces with DME, which pulls the contaminants out of the cardboard. The system then recycles this solvent, allowing for continuous operation without creating waste.

“The reactor process allowed us to extract the contaminants into separate fractions,” Wilson shared, noting the successful separation of oils, water, and dryer solids into distinct components.

Pizza box recycling on the front lines

The implications of this research extend beyond just cleaner recycling. Originally part of a research initiative linked to the Defense Advanced Research Project Agency (DARPA) ReSource Program, the technology developed could significantly reduce the logistical footprint of military operations by transforming waste into useful resources.

This has potential benefits for operational security and efficiency, particularly in hostile environments where supply lines are vulnerable.

“Knowing that this works for the highly contaminated pizza boxes has helped validate the system for use in the battlefield,” stated Jeff Lacey, another leading researcher on the project.

Lacey’s team is now focused on refining the technology to enhance its portability and efficiency, critical factors for deployment in military contexts.

Sustainable future

The successful application of this technology to pizza box waste not only promotes environmental sustainability but also opens doors to myriad other applications. From converting military waste to enabling more efficient battery recycling, the potential is vast.

“In essence, this research has many possible applications for national security and a net-zero future,” Lacey concluded.

This initiative represents a significant step forward in tackling the recycling challenges posed by everyday waste and could pave the way for innovative waste management solutions across various sectors.

Benefits of recycling pizza boxes

Recycling pizza boxes offers substantial environmental and economic benefits that contribute to sustainability efforts. Here’s a detailed look at these advantages:

Reduces waste in landfills

One of the immediate benefits of recycling pizza boxes is the reduction of waste sent to landfills. Pizza boxes are made from corrugated cardboard, which is biodegradable but can still take a considerable amount of time to decompose in landfill conditions.

Moreover, the presence of greases and residues can slow down this process and contribute to the production of methane, a potent greenhouse gas. By recycling, these materials are reused rather than occupying landfill space.

Conserves natural resources

Recycling cardboard, including pizza boxes, helps conserve valuable natural resources, particularly wood fibers. The fibers in cardboard can be recycled several times before they become too short for paper production. This means that fewer trees need to be cut down to produce new cardboard, helping to preserve forests and the biodiversity within them.

Saves energy

The process of recycling cardboard uses significantly less energy than producing new cardboard from virgin pulp. Energy savings arise from reduced demands in raw material extraction, transportation, and processing. By using less energy, recycling also lowers greenhouse gas emissions, contributing to climate change mitigation.

Prevents pollution

By recycling pizza boxes, pollution generated from the production of new cardboard is also reduced. The manufacturing of cardboard from virgin materials involves various chemical processes that can release pollutants into the air and water. Recycling helps to minimize these pollutants, leading to cleaner air and water.

Economic benefits

Recycling creates more jobs than landfilling or incineration. The process of collecting, sorting, and processing recyclable materials is more labor-intensive than using these materials as a fuel source or burying them. This means more employment opportunities in the recycling and manufacturing industries.

Encourages sustainable practices

Recycling pizza boxes can foster a culture of recycling and sustainability within communities. When people engage in recycling, they become more aware of their waste habits and environmental impact. This awareness can lead to broader support for other sustainable practices, such as reducing plastic use, conserving water, and supporting renewable energy.

Improves community health and safety

By reducing the amount of waste in landfills and decreasing pollution from new production processes, recycling helps to improve overall community health. Less landfill waste reduces potential soil and water contamination, and fewer emissions mean cleaner air and fewer respiratory issues for the community.

The full study was published in the journal Journal of Cleaner Production.


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