Recycling thermoforms gets a C+

Jan. 19, 2012
Why do thermoformed packaging such as blister packs typically end up in landfills, even though many of them are made of PC PET?

Thermoformed packaging such as blister packs and clamshells typically end up in landfills, even though many of them are made of PC PET, the material that is blow molded into soft drink and water bottles and highly recyclable. That’s a problem for manufacturers concerned about the sustainability of their products and product packaging. But realities of the economics of recycling will probably prevent the widespread recycling of thermoform-grade RPET for some time to come. (The “R” of RPET means the polymer comprises virgin material plus regrind, or recycled content.) In a pilot study conducted by thermoform packaging maker Dordan Manufacturing in Woodstock, Ill., the company shipped 50 of its RPET clamshells to a local recycling facility to determine how well the containers could be sorted. The automated waste-management facility that accepted the RPET samples sort different kinds of polymers using optics.

The equipment could not distinguish any difference between PET bottles and RPET thermoforms says Dordan Manufacturing sustainability coordinator Chandler Slavin. Theoretically, the two could be recycled together but this depends on a lot of factors, many of which are contingent on the sorting technology employed. In manual sortation systems, there are problems associated with the fact that clamshells and blisters come in all shapes, sizes, and materials, making it difficult to train personnel at recycling centers how to sort the packages by material type via visual cues inherent in package design. Most clear thin-neck screw-top beverage bottles are PET, making it easy to identify this recyclable from those destined for landfills, says Slavin.

Another issue: Industry experts suggest there may be fluctuations between the intrinsic viscosity (IV) of PET and RPET that would make them difficult to recycle together. The IV of a material, measured in deciliters per gram, depends on the length of its polymer chains; the longer the chains, the higher the viscosity of the material. Also, RPETs can comprise different ratios of PET, regrind, or recycled polymers. This is one reason why the National Association for PET Container Resources (NAPCOR) concluded it would be easiest to just recycle PET thermoforms together and keep them out of the PET bottle recovery system.

Mail in your waste

TerraCycle's goal is to eliminate the idea of waste. It does this by creating national recycling systems for previously non-recyclable or hard-to-recycle waste. Anyone can sign up for these programs and start sending the company waste. The company converts this into a wide variety of products and materials. According to the company, it has 20 million people collecting waste in over 20 countries and has diverted billions of units of waste, using them to create over 1,500 different products available at major retailers ranging from Walmart to Whole Foods Market.

The recycling of thermoforms is an evolving situation, says Slavin. Consequently, there are no standard practices; all collection, sortation, and reprocessing practices are dependent on the end market of the recyclate, which differ from region to region. And information about recyclability of specific materials often gets handed down like folklore among thermoform manufacturers and other interested parties. “Waste management is a large, complicated, and mature industry slow to adopt new technologies and processes due to inconsistencies inherent in North American recycling behaviors and established patterns of material recovery,” she says. For example, “A package or material type will not be collected for recycling if there is no buyer.” Says Slavin. “And there will be no buyer if there is not a consistent quantity and quality available for reprocessing. Moreover, lots of post-consumer plastics collected for recycling get sold to China where the cost of manual sortation is less than the cost of domestic sortation. This subtracts from the available recycling stream in North America, making the supply-demand amounts necessary to sustain the process of recycling difficult to quantify.”

In addition, a community’s ability to recycle a package with limited recyclability, like RPET thermoformed containers, can be dictated by whether facilities are private or municipality owned, says Slavin. “Private facilities tend to be better run and maintained than municipally funded ones,” she says. “They also tend to be more economically sustainable. And they incorporate more sophisticated systems for sorting and reprocessing. Other factors include the geographical location of the facility (east vs. Midwest vs. West), which determines what types of materials are collected for recycling and technologies used, based on the available end markets.” And consider the collection scheme, says Slavin. “How the materials are collected for recycling – curbside, drop off, single stream, or comingled – determines how the material comes to the recycling facility,” she says. “This also affects how and what materials are collected for recycling and what sortation systems are used.” Complicating matters further, buyers’ specs, or the qualified indicators a buyer outlines to a supplier of PC plastics upon procurement, require the material be of a specific material type — for instance PET — and packaging type — like thin-neck screw-top PET beverage containers. For instance, most buyers of PET indicate they do not want bales with RPET thermoforms included in the mix for fear of contamination. This discourages MRF’s from making investments into the sortation technologies necessary to sort RPET thermoforms from look-alike contaminates like PVC.

The Sustainable Packaging Coalition (SPC) developed the Labeling for Recovery Project, intended to educate consumers on what types of packaging is recycled and what is not via a simple labeling scheme modeled off the U.K.’s OPRL, On-Pack Recycling Label. Under the scheme, the label lists the components of the packaging and the material it is made from. It is intended to tell consumers tangible information about what can and can't be recycled in the U.K. rather than what is assumed to be recyclable,” says Slavin. “The hope was to have consumers understand recycling based on the realities of the current system, thereby establishing a demand for increased material recycling. But in developing the initiative, the project team ran into some obstacles in regards to data applicability. Difficulties for them arouse such as how to determine the types of packaging recycled and the quantity recycled in different geographical regions; whether a community has access to a facility capable of recycling the packaging, and whether collection, end markets, and automated sorting systems are available. What is the quantitative and qualitative distinction amoung ‘recyclable,’ ‘limited recycling,’ and ‘not recycled?’ Where is the data coming from? When was the data collected and what was the method? What if data doesn’t exist for a specific packaging type? What about those programs that are not considered in the EPA’s figures, like mail-in programs such as TerraCycle in Trenton, N.J.” she says.

Industry figures suggest that the amount of American communities capable of recycling PET thermoforms is 30 to 59%, which falls within the ‘limited recyclability’ category as per the FTC Green Guides’ definition. “This is changing, however, as industry begins to take a more proactive approach to the recovery of packaging,” says Slavin. “I foresee the management of recyclables as shifting from municipally to privately owned systems, due in part to the success of techniques observed overseas.”

How recycling works

When a clear, PET beverage bottle goes in a curbside bin, the bottle is often picked up on the same truck as the material destined for landfill, which can be contracted by the municipality. Usually the landfill and recovery facility are located geographically close to one another so the recyclables are dropped at the recycling facility and the waste at the landfill — transportation is one of the more costly considerations of the waste management industry.
Once recyclables make it to the reprocessing facility they are “dumped” on the plant floor where a variety of conveyer belts spread the material on the line for easier identification. Paper is usually sorted first, falling through slits in a tumbler due to weight and dimensions. Plastics are sorted manually or automatically, depended on the facility. In manual systems, workers on the line visually identify materials of a specific type, i.e. HDPE milk jugs. They remove the jugs and place them in separate containers that go to another sorting scheme in the facility or are baled for transportation to an intermediate reprocessor. One popular automated sortation technology uses optics to separate PET from PVC and other un-desirables. Aluminum is sorted from other recyclables, and glass is sorted through a weight-based scheme. Sometimes, the municipally-contracted hauler or reprocessor separates materials by feedstock type (i.e. paper, plastic, and glass) and then sells the materials to an intermediate plastics or paper reprocessor. It is often privately owned and employs more sophisticated sorting techniques based on the requirements of the end-market.

RESOURCES:

Dordan Manufacturing Co. Inc., www.dordan.com, www.recyclablepackaging.org

For more information, check out YouTube videos on “how recycling centers work” like http://www.youtube.com/watch?v=_GP3JuiX5BY.

Visit this link for a list by material type of what is recovered based on percent generation with the focus on containers and packaging: http://www.ftc.gov/bcp/edu/microsites/energy/documents/Green-Guides-Summary-of-Proposal.pdf

The document describes what is recycled and in what quantities thereby demonstrating what is not: http://www.epa.gov/osw/nonhaz/municipal/pubs/msw2008data.pdf

Slavin’s research culminated in the release of her Recycling Report: The Truth about Clamshell/Blister Recycling in America with Suggestions for the Industry. http://www.dordan.com/pdf/dordan_recycling_report.pdf

Terracycle, www.terracycle.net

About the Author

Leslie Gordon

Leslie serves as Senior Editor - 5 years of service. M.S. Information Architecture and Knowledge Management, Kent State University. BA English, Cleveland State University.

Work Experience: Automation Operator, TRW Inc.; Associate Editor, American Machinist. Primary editor for CAD/CAM technology.

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