A Shakopee, Minnesota, material recovery facility (MRF) plans to salvage more bottles with fewer people by upgrading its optical sorter.
Dem-Con Cos. provides a wide variety of services to the Twin Cities area, including commercial and residential single-stream recycling. By upgrading its original optical sorter for plastics, an Aladdin supplied by MSS, Nashville, Tennessee, with technologies from the company’s newer Cirrus PlasticMax, Dem-Con’s management team hopes to save more polyethylene terephthalate (PET) bottles from the landfill.
“For us, one of our [top] challenges is labor,” Dem-Con President Bill Keegan says. “We have a 3 percent unemployment rate in Shakopee where we’re at. We really struggle to get enough people to [work] on the line. We’re able to minimize or reduce our manual labor requirements by doing this.”
Felix Hottenstein, MSS sales director, says the upgrade, which involves replacing the Aladdin’s sensor head, sensor housing, control panel, air-ejector array and catcher hood, will result in more efficient sorting.
The upgrade, which Dem-Con expects to complete by the end of July, will reduce its need for manual sorting by one full-time employee.
Keegan says the original sorter was able to identify about 70 percent of the bottles passing over the company’s container-sorting line. With the upgrade, he anticipates that total will grow to about 92 percent.
“It would roughly equal an additional 825 tons of PET captured per year that we weren’t capturing previously,” Keegan says.
Hottenstein points out that, with an inefficient sorter, not only is the recycler losing plastic it can sell, it’s also paying for more material to go to the landfill.
The resolution of the Cirrus Plastic- Max sensors is four times greater than the Aladdin’s, and the technology is sensitive to wavelengths, such as those reflected by PET-glycol products, that are difficult to pick up.
“Before we had a pretty coarse pixel grade to identify the bottles and the different polymers,” Hottenstein says. “Now we have a much, much finer grade to make those detections. That really helps, especially on bottles where there are big labels on them, and we can only see a small portion of the PET, for example.” It’s also helpful on crushed bottles, where the amount of PET visible to the sensor also might be quite small, he says.
The Cirrus PlasticMax’s near-infrared (NIR) cameras differ from other optical sorters in that they sequentially scan all NIR frequencies rather than splitting the light into separate frequencies. Hottenstein says the equipment receives the full intensity of all wavelengths using this approach.
Compared with older optical technologies, the Cirrus PlasticMax detects more wavelengths, allowing more precise material identification
In addition to the new camera technology, Dem-Con’s upgraded sorter will boast improved software with more efficient sorting algorithms, as well as easier access to halogen lamps and air valves.
The upgrade is “fairly significant,” Keegan says. “It’s replacing all the major components of it. You’re having to put in new acceleration belts and everything else. Basically, replacing the vision system and air jets and valves.
“The new technology is just a lot better at recognizing and identifying and punching those materials out of the stream,” Keegan adds.
With the upgrade, Dem-Con will retain only the old sorter’s original frame and conveyor, Hottenstein says.
Keegan says Dem-Con processes about 8 million pounds of PET yearly. In addition to PET, it also produces bales of polypropylene and colored and natural high-density polyethylene and separates film and bulky rigid plastic. The company has four optical sorters. The oldest is the one being upgraded. The other three sorters focus on fiber.
“Any state-of-the-art equipment in our industry becomes obsolete in five years,” Keegan says. It might continue to function but not at an optimum level. “The new optical sorter technology is so much better and far superior to what we had back then.”
The author is a correspondent for Plastics Machinery Magazine and can be contacted at email@example.com.
Pulverizing mills: Powder King’s line of industrial pulverizing mills can be used by compounders, polyvinyl chloride (PVC) recyclers and manufacturers of plastic lumber and vinyl fencing. It includes a number of models, from the PKA-120, which is capable of hourly throughputs ranging from 800 pounds to 1,100 pounds, to the PKA-Super Mega and PKA-Velocity, which have hourly throughputs that top out at 2,200 pounds. The PKA-120 is shown.
What’s new? The use of a new, embedded controller, the EC200, that replaces the need for a programmable logic controller and several other devices formerly required for the operation of the mills. The new controller is available with all new Powder King pulverizing mills, and the company says it is working on a retrofit kit for operating systems on existing mills.
Benefits: Enhanced control functionality. With the EC200, users can operate their mills remotely, as well as locally. The user-friendly controls also monitor as many as 12 variables, providing access to trending machine data. Because all necessary inputs and outputs are built into the EC200, the controller is easy to troubleshoot and maintain.
Tip-Tite: Flexicon’s Tip-Tite drum dumper has been designed for materials that clump together or flow poorly. The dumper uses a hydraulic cylinder to dump containers of materials; it employs a pneumatically actuated slide gate valve to control material flow. According to the company, the product can be used by recyclers to dump drums of pellets or pigments. In one case, a plastics recycler uses it to handle 55-pound sacks of a mineral additive. With the ability to handle loads ranging from 30 gallons to 55 gallons, the dumper has tilting angles of 45 degrees, 60 degrees and 90 degrees.
What’s new? A square outlet through which pellets or other materials can flow. The outlet makes it easy to dump round drums into square flanged openings. Circular outlets also are available.
Ecopick: Picvisa Optical Sorting’s delta-style robot uses artificial intelligence, along with visible light and an optional near-infrared light source, to recognize objects, which it sorts using a suction cup.
Benefits: Cost-effective, efficient sorting. The robot can help recyclers more effectively reclaim salvageable materials while reducing reliance on human labor.
BKG FlexDisc: When used in extrusion operations, BKG FlexDisc filtration media increase the filtration area of Nordson screen changers. They are especially useful in bottle-to-bottle and PET fiber recycling applications.Compatible with Nordson’s BKG NorCon D-SWE, BKG HiCon K-SWE-4K-75/RS and BKG HiCon V-Type 3G screen changers, they can be retrofitted by replacing the screen changers’ piston with one with a special retainer.
What’s new? Updates to the original BKG FlexDisc, which debuted in 2014. The filtration media now can be added to screen changers in stacks of two to four.
Benefits: Even greater increases in filtration area and improved filtering. With the BKG FlexDisc, users can expand their screen changer’s filtration area and achieve finer filtration, greater throughputs, longer filter service life and reduced backflush volume—all without the need for a bigger screen changer. According to Nordson, the latest version of the BKG FlexDisc creates 25 percent more filtration area than the previous version.
Tomra Insight: This cloud-based data platform collects information from connected sorting machines and provides the data to operators through a web interface. Tomra provides data transmission and storage in partnership with Microsoft Azure.
What’s new? The platform, which provides digital metrics about factors such as throughput, material and size distribution and acceptance and rejection rates.
Benefits: Access to near real-time data that can guide better, evidence-based decision-making. This helps users reduce downtime, maximize throughput and optimize sorting machine performance and preventive maintenance plans.
Diverter valves: Kice’s automatic 67-series diverter valves are used to convey resins and additives, including recycled materials. The heavy-duty, cast-iron valves come in six sizes and are available with air-operated controls, manual controls or electric actuators.
What’s new? Upgrades that allow material flowing through the valves to be diverted in three different directions. Previously only available as two-way valves, the series now includes a version with a three-way valve. Its three outlets provide one straight-through passage and two 30-degree branches. Other improvements include more precise blade positioning, better drive system guards and an engineered square drive shaft.
Benefits: Improved durability. More precise blade positioning reduces wear on the leading edge of the diverter blade. In addition, the new drive shaft helps prolong equipment life and ensures blade alignment. Additionally, the guarding eliminates pinch points and meets American National Standards Institute safety standards.
KSp: This portable dedusting system from Hosokawa Polymer Systems is designed for material throughputs of up to 250 pounds per hour, which makes it suitable for small batches or use in labs. The KSp can be hand-fed, but an optional loader is available. It has a multistage 304 stainless-steel dedusting throat in addition to a mechanism for removing static from material, such as film.
What’s new? The KSp, which was introduced in February at the 2019 Plastics Recycling Conference. The new unit is the smallest of the KS series—the “p” at the end of its name denotes it’s portable. Versions released earlier include the next smallest deduster in the series, with a capacity of 1,000 pounds per hour.
Benefits: Portability, flexibility and accessibility for maintenance. The dedusting system has easy-to-adjust cut points and can handle a variety of materials. It has a small footprint and can be cleaned with ease. An optional stand works with drums, gaylords and bins.
Reb-X Press: This heavy-duty, two-ram baler from Sierra can handle a wide variety of materials, including plastic bottles. It produces bales measuring 46 inches by 31 inches by 62 inches and weighing from 1,250 to 1,400 pounds, in the case of PET bottle bales. It has a dry-cycle capacity of 12,000 cubic feet per hour and a dry-cycle time of 15 seconds.
Benefits: Versatility. The baler is suitable for companies that have multiple facilities but don’t have enough volume to justify multiple pieces of equipment. It also can take the place of stationary equipment during maintenance shutdowns. The Reb-X Press also is ideal for locations that have no access to electrical power.
Novolex, Hartsville, South Carolina, hopes to set a good example for recycling plastic bags with its Bag-2-Bag program.
Plastic bags tend to get a bad reputation in the United States. Many material recovery facilities (MRFs) across North America view them as contamination because they get tangled in sorting equipment. For more than a decade, some city and county governments in the U.S. have proposed and implemented taxes on plastic bags or banned them in an effort to reduce plastic litter and consumption.
Yet, Novolex, Hartsville, South Carolina, sees opportunity to close the loop on plastic bags. The company started its Bag-2-Bag recycling program in 2006 to reduce the amount of litter caused by plastic bags and to turn those old bags into new bags at its Novolex Hilex Poly recycling center in North Vernon, Indiana, or its recycling facility in Shawano, Wisconsin. The company also has about a half dozen other recycling partners to help. Phil Rozenski, senior director of sustainability and corporate affairs at Novolex, says the program offers a sustainable solution to the country’s plastic bag concerns.
Through Bag-2-Bag, Novolex connects with grocery stores and other retailers. Collected bags are gathered into bales that are transported to one of Novolex’s recycling facilities in North Vernon or Shawano. The recycling center then processes the used bags into recycled pellets. The pellets are used to manufacture new plastic bags.
“As a company, we consume more than 100 million pounds of recycled polyethylene film in a year,” Rozenski says. “We’ve gotten good with recycled content, and we’ve helped to mentor other companies to help us meet the demand for recycled content. We hope we can set the example, and more companies will do the same thing—that’s really who we are.”
Novolex contracts with a few regional and national retail chains in the U.S. and Canada. These retailers will collect and bale plastic bags and plastic packaging film from consumers and their warehouses. A retailer informs Novolex when it has a trailer full of plastic bag and film bales, and Novolex hires a firm to haul the trailer to one of its facilities or recycling facility partners.
“We determine where to send it depending on our workload,” Rozenski says. “We work with about a half dozen [third-party recycling partners]. Some partners are on the West Coast, some are in the central U.S., some are in the South. Part of sustainability is reducing how much you move stuff, so we feel it’s key to own two facilities and have partners.”
Once Novolex receives the bales, Rozenski says the company or its partners load them into a bale breaker. “We have a guillotine that shaves off layers and opens up the bale. Then, we do a visual inspection to see if anything doesn’t belong. It then gets shredded.”
One common contaminant is grocery store receipts. To remove the receipts, Novolex places the shredded polyethylene (PE) into a tank. The PE floats, while the receipts and any other contaminants sink.
From there, Novolex performs an extrusion process and turns the PE film into pellets. Finally, those pellets are used as feedstock for plastic bag products. The company’s plastic bags typically use about 25 to 40 percent recycled content.
“We use a mix of content in the bags,” Rozenski adds. “Typically, we have 30 percent recycled content. Some are higher, some are lower. We could do 100 percent, but there’s not enough supply. We’re looking at how to grow our recycled content and are constantly looking for new partners to meet that demand.”
To ensure contamination remains low in bales, Novolex regularly communicates with its retail chain partners. Rozenski says the company works with partners to educate them and their employees on what is considered contamination.
Through the Bag-2-Bag program, Novolex can accept plastic retail bags, produce bags, newspaper bags, dry cleaning bags, cereal box liners, paper towel film wrap, toilet paper film wrap, wrap on cases of soda and canned vegetables, sealed air pouches in mailed packages and Ziploc or other zipper-style bags (provided the zippers are removed prior to recycling).
The program does not accept salad bags, frozen vegetable bags, pet food bags, polyvinyl chloride, polystyrene, polyurethane foam, polypropylene, polyethylene terephthalate trays, plastic bottles, metals or potentially hazardous materials, such as medical waste.
Rozenski says the quality of bales Novolex receives is typically good; however, some level of contamination is usually present. If the company notices a trend, it works to educate the retail location.
“Every now and then, someone in the back end of a retail store’s distribution center will see plastic material, like nylon strapping, and they add it,” he says. “We mark these bales. If we find something, we work with that retailer to educate employees not to put that in there, and it changes.”
To maintain good partnerships with the regional and national retail chains, Rozenski adds that it’s important to connect with four types of people: procurement personnel who buy the bags, operations personnel who collect the bags, marketing personnel and sustainability personnel.
One of the biggest challenges in the program is educating retailers that plastic bags don’t have to be just one color. Recycled plastic bags aren’t usually the vibrant colors some retailers are used to; they are usually gray or brown as a result of mixing plastic film together.
“It’s a different color,” Rozenski says. “It’s easiest to make a tan or gray bag. Once the retailer understands that gray or brown bags communicate sustainability, they get it.
“Partnering with your customers is key,” he continues. “Everyone in the value chain has to work together. That’s the key to being more sustainable. Get everyone involved together, and you can solve more complex problems.”
Danny Schrager has specialized in plastics recycling and sustainability for 30 years. In that time, he’s helped recycle more than 800 million pounds of postconsumer and postindustrial plastics.
He started GearedforGreen in 2012. The New York-based company provides a wide range of consulting services to help companies achieve their sustainability goals. Notably, GearedforGreen maintains a contracted network of recycled resin suppliers that collectively produce more than 1 billion pounds of recycled resin per year, which it connects with clients that need recycled resin.
The company also helps its clients recycle plastic, increase use of recycled resin in their products and make and use plastic packaging more sustainably. Additionally, GearedforGreen assists its clients with implementing education and outreach programs, such as communicating about recycling initiatives, using ocean plastic and participating in beach cleanups.
Schrager says his passion is helping connect the plastics supply chain in circular economies “to make plastics sustainable together.”
How has plastics recycling changed over the years? A few changes come to mind; one would be technology development. That includes chemical plastics recycling; that’s a very big development that’s going to make significant changes in the plastics recycling landscape.
And, certainly advancements in technology in terms of cleaning, washing, filtration and separation, they’re helping us and many others to improve the quality of the recycled plastic materials, so they could be much more widely used as raw materials in everyday manufacturing. Manufacturers are used to using virgin resin, and recycled [material] quality isn’t quite as good as virgin resin. So, the better our technologies are to make clean recycled pellets, the more widely used they’ll be.
You can see that the industry is really getting behind [the] circular economy in a big way. There [are] more and more connected, collaborative, transparent supply chains starting up. Once you start to create these circular economies and supply chains, you start to use resources more effectively. You start to design products more sustainably, with end-of-use sustainability in mind. Those levels of innovation are having profound changes.
I also see something externally in the market that’s happening today that’s having a big [impact]. It’s this groundswell of consumer awareness. It is really helping drive plastics recycling, especially in areas surrounding single-use plastic packaging and ocean plastic waste, which are huge problems. What’s happening today is consumers are making purchasing decisions and also brand-loyalty decisions at least in part with sustainability and social value in mind. You start to see manufacturers, brands, retailers and distribution really listening. And they’re making investments, with tangible steps toward creating plastics sustainability solutions. So that’s a big change.
This global issue with China shutting its doors to plastic scrap and now India following suit, it’s causing short-term challenges to the plastics recycling industry. We’ve seen quite a few companies that relied on exporting their plastic waste now having to resort to landfilling.
But I think this may be a silver lining because longer term, this may be the impetus for greater investment here in the USA. And you can see more innovation and investment of recycling facilities and technologies to handle plastic waste here in the United States and our own infrastructure.
What lessons have you learned about the industry? When it comes to plastic scrap, producing recycled resins and dealing with contamination, one lesson I’ve learned, and I think most everyone in the plastics processing world has learned over time, is blend, blend and blend again.
Plastic scrap, especially postconsumer scrap, generally arrives very inconsistently, on a bale-by-bale basis, or even on a truckload-by-truckload basis. But when you look at it as a whole, it’s actually fairly consistent. So, the challenge for converters who take plastic scrap and actually create new recycled materials is how do you make that material consistent? Because consistency is critical to those that are using your recycled raw materials to make new products. Blending, both preblending and postblending, can turn inconsistent plastic waste material into consistent, sustainable raw material. In the industry, we call this phenomenon being “inconsistently consistent.”
Where do you see opportunities for plastics recycling? What about challenges? Plastics are one of those things that has incredible benefits to mankind, like preserving food longer. But, obviously, plastics are also wreaking havoc in terms of the environment, and practically everyone has been made aware of this plastic pollution and single-use plastics and ocean plastic waste. There are literally billions of pounds of brand-new plastic materials being produced every year, and yet, 85 to 90 percent of all that winds up in a landfill, or worse.
I think there are incredible upcoming opportunities for all of us in the plastics recycling and sustainability sphere. Technology is probably No. 1, including, as I mentioned earlier, chemical recycling. We work with supply-chain partners that utilize incredible chemical technologies, including chemical friction, that allow us to remove and decoat all types of surface coatings from plastic—to remove exterior laminate and paints and metallics and the print and inks—and to do all of that without negatively impacting the physical properties of the polymers themselves.
These types of technologies are helping drive millions and millions of pounds of plastic recycling that were in the past too challenging to recycle.
On the flip side, the challenge with all these new technologies is making sure that they’re cost-effective, especially compared to prime virgin plastic. Because, at the end of the day, if the technology cost is too high, the end result won’t be cost-effective, and that technology won’t be deployed in any wide basis.
What is a more convincing argument about sustainability to the business world: environmental altruism or economic self-interest? In the past, I easily would have said economics for certain, and specifically [price per pound] economics. Generally speaking, sustainability has to be economically viable for it to be successful long term. That’s true for industry, and it’s also true for consumer purchasing.
But I think, today, there’s a real argument that says social brand value may ultimately have even greater importance than in the years past. Social value can really move the needle in terms of brand loyalty, which can have a direct impact on a brand’s top-line revenue and even their ability to gain shelf space. If implemented right, social value in many ways can surpass traditional price-per-pound value.
So, with consumers now making purchasing decisions in part based on a brand’s social purpose, we’re seeing social value having tremendous importance today. And that’s why you start to see leading retailers, including Walmart and Target and others, setting these very lofty plastics sustainability goals for their whole supply chain and leading brands—Procter & Gamble, Unilever, Nestlé and others—investing so heavily in sustainability and the circular economy. I think it’s because in today’s social media world, information, whether it’s good news or bad news for brand owners, spreads in minutes and can make or break a brand.
So, you’re starting to see a trend in terms of plastics sustainability where today social brand value and environmental altruism may wind up surpassing traditional price-per-pound economics that everyone focused on yesterday.
How important to you are concerns about “greenwashing” — environmental claims that don’t hold up? It’s huge. One of the important aspects about creating a circular economy is that there’s full collaboration and transparency throughout the entire supply chain. It enables you to track as a chain of custody plastic waste from source of origin throughout the recycling supply chain, turned into new raw materials, back into new products and [then] certify those, measuring carbon footprint, etc. Ensuring that you are not going to be, whether on purpose or by mistake, participating in any kind of greenwashing, which is essentially touting your sustainability, but maybe in reality they’re not as sustainable as consumers thought they might be.
What misperceptions about plastics recycling do you wish you could debunk? I would say that plastic bags—like grocery or retail bags, films or wraps—aren’t being recycled and aren’t recyclable here in North America. Because that is, in fact, completely not correct. There are increasing amounts of plastic films and bags being recycled in North America. There’s a lot of talk about plastic bag bans. We’re very active in this space. But, in reality, plastic films and bags and wraps are very much recyclable, and not just into plastic decking and plastic lumber. With today’s advances in new recycling, filtration and cleaning technologies, plastic films, bags and wraps are being converted back into clean recycled plastic resins and made back into brand-new plastic film products over and over again.
There’s a growing infrastructure here in North America to recycle millions of pounds of these plastics.
The good news is, while the consumer packaged goods industry and retailers generate lots of plastic waste—grocery bags, retail bags, stretch wrap, shrink wrap, bubble wrap and all kinds of plastic wraps—these same companies also consume and buy themselves as well as sell significant amounts of brand-new plastic trash bags, can liners, commerce shipping bags, that are all made of the same thermoplastic materials. It’s an ideal application for the circular economy!
So, the key really is, and the challenge really is, we must treat plastic waste not as waste but instead as a renewable resource that we can turn into brand-new products to increase plastic film and bag recycling on our side, at least. We focus on technologies and creating formulations that foster circular-economy collaboration.
What advice can you offer to younger people entering the industry? My advice would be to get passionate. Young folks shouldn’t jump into the plastics recycling and sustainability industries simply for their own economic reasons, although, obviously that’s important. I think, beyond that, youth should get involved because they’re passionate about plastics, they’re passionate about our planet and environment and about creating positive change in the world.
Who has served as your role model? That would definitely be my dad. My dad, before me, was a plastics pioneer himself. He taught me, more really by his actions than his words, about perseverance and hard work and overcoming obstacles in life and in business and, really importantly, about persistence and dedication: dedication to the customer, dedication to your trading partners, to the value of long-term partnerships. [He] definitely taught me a lot about thinking differently and being innovative and creating solutions where others said solutions weren’t possible. We always believe we can create solutions.
He was involved with plastics recycling for many, many years. He’s 80 years old today and happily retired.
What professional accomplishment are you most proud of? I’ve had a lot of great experiences. But if I had to single out one specific accomplishment that I’m proud of, it probably would be a plastics sustainability solution that I developed and implemented for Walmart a number of years ago.
Walmart came to us to help find a solution to their disposable plastic shipping hangers. At that point, Walmart was disposing these plastic hangers into landfills—around a billion plastic shipping hangers annually—which came in from apparel vendors from all over the world.
Disposable plastic shipping hangers were very challenging to recycle because they were made from a number of different polymers that were all mixed together, and they couldn’t be melted together. Plastic hangers were made from polypropylene and polystyrene and K-resin (styrene butadiene copolymer), which aren’t compatible in a recycling process because they melt at different temperatures. But, also, plastic containers are heavily contaminated with all types of nonplastic waste—paper, fabric, foam, tissue paper, stickers, adhesives, metals, rods, clips and hooks, all that stuff—and get all entangled together.
We designed, built and operated the plastics recycling facilities ourselves to help solve this problem for Walmart. We built a state-of-the-art plastics recycling operation. We installed hydrocyclone resin separation systems to separate polymers by specific gravity at very high speeds and with great accuracy. We installed metal- and air-classification separation systems, color sortation, all in a highly automated process with very little manual labor required.
To authenticate our work, we also measured our own carbon footprint through the entire operation, including from sourcing the material to our facilities. We verified that our carbon footprint was an 80 percent carbon footprint reduction versus comparable prime resin.
We also obtained FDA (Food and Drug Administration) compliance, as well, for the recycled plastic resins we produced from consumer-used plastic hangers. To go full circle, ultimately, we worked collaboratively with the supply chains and helped close the loop for Walmart, with product back in their stores in the lawn and garden department and other departments made entirely from Walmart plastic hangers. It was a great experience for me personally, as well. I’d probably say that’s my most enjoyable or fulfilling professional accomplishment related to plastics and sustainability.
Just as materials and packaging designs evolve, so must the recycling industry to capture value from bioplastics.
We know the benefits of plastics. They often are the more sustainable option when evaluated against other materials. Reducing a vehicle’s weight by 10 percent, which often is accomplished by using plastic to replace metal components, can increase fuel economy between 5 percent and 6 percent. It takes 10 times the amount of resources to produce food compared with the plastic packaging that protects and preserves it. Plastic products used in the medical field contribute to improved infection control. But just because plastics already were the sustainable material of choice doesn’t mean we shouldn’t continue to find ways to improve and address the unique challenges they have.
Sustainability is important as the plastics industry evolves alongside consumer perceptions, brand owners’ understanding about the recoverability and circularity of products and packaging and supply chain sophistication related to reduced environmental impacts. A 2018 Deloitte survey found two-thirds of shoppers are willing to pay extra for sustainable products. Brand owners such as PepsiCo have made public commitments to circular visions of their plastic use (“to build a world where plastics need never become waste”). Each of these factors plays an important role in optimizing products, affecting material selection, construction and disposal. This is echoed in legislative policies at all levels of government.
Within the realm of material development, companies have worked to create plastics with unique functional and compositional attributes. One family of polymers that continues to rapidly grow in popularity is bioplastics. They are either bio-based, meaning they originate wholly or partly from renewable feedstock; in some way biodegradable, such as through industrial composting facilities; or bio-based and biodegradable.
As a concept, bioplastics are not new—the first man-made plastic, Parkesine, was bio-based, and Henry Ford famously used corn- and soybean-based plastics to manufacture automotive parts until World War II. But the 1990s saw increased commercialization of bioplastics.
Professionals working with these polymers have had to think about how they fit within the existing recycling infrastructure and how that infrastructure can be adapted to handle these materials.
For certain bio-based plastics, recycling is a relatively simple process because many are chemically identical to traditional plastics. For example, Braskem’s I’m green polyethylene (PE) is 100 percent bio-based and behaves no differently than fossil-based PE at material recovery facilities (MRFs). Coca-Cola Co.’s PlantBottle, which is up to 30 percent bio-based polyethylene terephthalate (PET), is another example. More than 1 billion bottles have been produced with bio-based PET, and they’ve presented no problems to recyclers. But manufacturers of novel polymers should keep recycling in mind to ensure they don’t unintentionally disrupt the recycling system.
New bio-based polymers in development, including polyethylene furanoate (PEF) and polytrimethylene furandicarboxylate (PTF), have physical properties that may make them more advantageous in certain applications than other available plastics. In particular, the two bioplastics exhibit increased gas barrier properties compared with PET. However, these polymers shouldn’t be mixed with PET in large volumes because they risk becoming contaminants in MRFs that don’t use optical sorting to identify and separate plastics. For instance, Wilmington, Delaware- based DuPont Industrial Biosciences has worked to prevent recycling stream disruption by reducing the risk of contamination by these bioplastics. DuPont Industrial Biosciences won the 2017 Innovation in Bioplastics Award in conjunction with Archer Daniels Midland for work commercializing a bio-based precursor to PTF.
Regardless of the extra care required to recycle some of these materials, the benefits and opportunities presented by bioplastics and bio-based polymers are considerable. Bioplastics that are industrially compostable provide unique end-of-life advantages because they can break down completely via microbial digestion in the same environment as food or yard waste. This means these products can be used to help divert food waste from landfills—food waste can represent as much as 30 percent of the volume of a landfill by weight—to more sustainable end-of-life options, such as industrial composting or anaerobic digestion.
Other compostable products used in food service also can promote diversion. In closed-loop systems such as stadiums, airports, arenas, etc., consistent selection of compostable food service products ensures little to no contamination of the recycling streams with compostable bioplastics and no contamination of the compost stream with noncompostable plastics.
A compostable polymer isn’t limited to use in food service applications. Firstly, the market for food service ware and compostable bags is a small part of the much larger plastics industry. A company only focusing on these products limits its potential growth. In addition to being bio-based or biodegradable or compostable, these polymers have other characteristics that can be put to good use.
A great example of a bioplastic that not negatively affecting the recycling industry is polylactic acid (PLA). PLA is an industrially compostable plastic used in a wide variety of compostable products. But companies also produce PLA products outside this space. It is used widely in 3D printing because of its lower melt point and less pungent smell than some alternatives. Companies such as Total Corbion, Gorinchem, The Netherlands, are developing noncompostable grades with increased toughness and heat tolerance for other applications, including automotive.
Still, these products need an end-of-life option other than the landfill. For PLA, mechanical recycling remains an option. As a bioplastic that has been commercially available for a long time, the recycling industry does have some familiarity with PLA. A commonly expressed concern about allowing PLA to be included in single-stream recycling is its potential impact on other polymers, most notably PET. But PLA is no longer commonly used in soft drink and water bottle formats, reducing the potential of confusion via hand-sorting. PLA can be readily differentiated from PET using near-infrared technology and also can be removed through mechanical processes such as air or float separation.
Multiple studies also have shown that its presence in the recycling stream has minimal impact on the quality of the recycled material produced. A 2016 Wageningen Food & Biobased Research study on PLA and nine other potential contaminants showed no specific threats from PLA contamination, unlike the extreme impact of polyvinyl chloride (PVC). A 2017 study from the same institute showed including PLA at 10 percent in a DKR-310 (Germany’s Green Dot program) film mixture did not negatively affect the film’s properties and increased impact strength.
Currently, NatureWorks, Minnetonka, Minnesota, which has commercially produced PLA for decades, has a trial project in Los Angeles where PLA is collected from secondary plastic recovery facilities. Work also is being done to develop markets for recycled PLA (rPLA) beyond creating filament for 3D printing—companies such as Bioplastic Recycling Inc., Los Angeles, aim to take rPLA and make rPLA/wood composite products, such as coffee tables and embossed signs.
As industries transition from linear to circular supply chains with a greater focus on sustainable feedstocks and multiple end-of-life options, bioplastics companies are well-positioned to respond, but so are recyclers. To do so, they will need to consider the current recycling infrastructure to ensure new opportunities are being made for bioplastics that do not come at the expense of other materials.
Just as manufacturers of new and novel polymers should consider recycling, recyclers should be responsive as well. A system that is unwilling to entertain change has to be content with the stable of polymers that exist, and that does not reflect the broader community’s interest in new and novel plastics and plastic products. To prepare for a future where more bioplastics are produced, new identification and processing technologies will need to be developed and adopted for current recyclers to continue to be able to serve in their important role. Just as materials and packaging designs evolve, so must the recycling industry to capture value from these new streams.
All of this takes consideration, communication and collaboration. We are in the early days of this process, which means the moment is now for stakeholders to thoughtfully explore these new opportunities to ensure we all advance the industry sustainably together.
The author is director of technical and regulatory affairs for the Plastics Industry Association, Washington, and the staff lead for its Bioplastics Division. Contact him at firstname.lastname@example.org.
3 Stages Water Filter
Butterfly Valve, Gate Valve, Check Valve, Ball Valve, Y Strainer - Diefei Valve,https://www.butterflyvalve-mfg.com/