PLASTICS RECYCLING: NOW MORE THAN EVER
Canadian PlasticsEnvironment Plastics Processes Sustainability Environment Green Development Plastics: Auxiliary Equipment
That font of knowledge known as "Wikipedia" defines plastic recycling as the process of recovering scrap or wa...
That font of knowledge known as “Wikipedia” defines plastic recycling as the process of recovering scrap or waste plastics and reprocessing the material into useful products, sometimes completely different in form from their original state.
Not bad insofar as it goes, but it skates over hidden depths of complexity and make-or-break decision-making for the company involved.
The Wikipedia entry also mentions that, with a “green”-inspired push towards ever-higher levels of recycling combined with rapid growth in plastics consumption in the developing world, more and more people are throwing their hats into the recycling ring – and in this, the anonymous author author is dead on. Witness, for example, the recent installation of a new plastics processing line at waste recycler Groupe RCM in Yamachiche, Que.
For plastics processors, meanwhile, the pressure to become more environmentally friendly – coupled with the high prices of virgin materials – means that reclaiming at least enough post-industrial plastic to attain the all-important “Made with recycled materials” label is now smart business.
The experts caution, however, against the pitfalls of a hasty leap into the recycling world. While it might seem too big an idea to fail, the Big Three automakers could tell you that bad planning can shoot down even the most bulletproof product concept.
IGNORANCE ISN’T BLISS
In an industry as broad as plastic recycling, an understanding of some fundamentals is crucial in putting a fledgling company on the right path.
To begin, there are two types of plastic available for recycling, according to Bob Wolfe, president of Action International, a recycling consultant and equipment supplier. “The first is post-industrial, defined as scrap in the production process before it’s gone out of the factory for its intended use,” he said. “The second is post-consumer, defined as material that’s already been used for its original intended use – for example, bottles from curb side pickup or used carpeting.”
For recycled material sellers, the design of a good recycling system depends on knowing the answers to three questions: what is your feedstock source, what is your desired end use or end product, and how much material do you want to recycle?
“It’s easy to say, ‘I see a lot of plastics in the gutters and I want to recycle it’, but this means nothing unless you identify the source of the plastic and determine how many pounds might be available in future,” Wolfe said. “Not knowing enough about the source can be a fatal mistake, as a constant supply of raw material is crucial for the success of the business.”
Once the source or sources have been nailed down, the next steps are to know in what form the material will arrive and how clean it will be. “The recycler needs to determine whether it will be collecting loose parts in Gaylords, baled material or purgings,” said Greg Parent, Canadian sales representative for Vecoplan LLC. “They also need to know the mix – which dictates how much contaminate they might have – as well as the sorting, separating and cleaning procedures; if you’re trying to separate PET and PVC, for example, it’s a different process depending on whether there’s a 50-50 mix or a 95-5 mix.”
And while it might seem to restrict future earnings, a recycler shouldn’t cast too wide a net when collecting the plastics. “Trying to recycle all types of plastics makes no more sense than recycling all types of metals,” said Bob Wolfe.
An understanding of the relative demand and market prices of the various plastics can save a lot of trouble here. “PET is the most popular recycled material, followed by HDPE and then film; for a newcomer to the recycling industry, any of these materials would make a good start,” said Tim Hanrahan, CEO at Erema North America. “Nylon, on the other hand, can be a trickier material to work with and is best left to the more experienced recyclers.”
The second big question involves end use. “If you want to sell the material on the open market – versus using it in a saleable product of your own – you need to explore whether you want to sell an intermediate product such as pellet or sheet, or a finished product,” Bob Wolfe said. “This decision has to be made early, because each has a different requirement on capital costs, operating cost and profit, and each requires a different operating technique.”
When selling on the open market, it’s necessary in some cases to satisfy requirements about quality and cleanliness levelled either by the FDA or equivalent local regulators. “If you’re trying to sell into the food industry, for example, there are very stringent requirements that have to be dealt with, particularly for start-up shops that haven’t proven yet themselves,” Wolfe continued.
Third, how much material does the company want to recycle? Be warned: unless you’re planning to process the common materials like PET in large amounts, it might not be worth the trouble, period. “The bigger recycling outfits can churn out 30 millions lbs. of PET annually,” said Tim Hanrahan. “By this scale, 20 million lbs. per year is probably the starting point for commercial viability. Five million lbs., which seems like a lot to most people, won’t begin to cut it.”
PROCESSORS DO IT TOO
We’ve been dealing mainly with the concerns of start-up recycling outfits to this point – those that haven’t had any real experience with plastics and who are looking to sell the material on the open market rather than use it themselves. On the flipside of the recycling coin are the plastics processors who do want to incorporate more of their own post-industrial material. “Generally, these shops are looking to advertise their product as having a given percentage of recycled material, and they’ve learned that it can be hard to buy this material from someone else, at least in large quantities,” said Bob Wolfe.
If you’re thinking that it should be easier for a processor to get into this field than for a start-up, you’re right. “First, processors don’t need to worry about the source of their material, or what’s in it, because they are the source,” Wolfe continued. “They’re recovering the plastic from their own bins – from out-of-specification goods, purgings, or simply unavoidable scrap such as edge trims – and don’t have contamination issues on the same scale as with post-consumer scrap.”
Second, he continued, most processors already have the floor space, electrical outlets and access to water to set up a recycling unit. The chances are good, too, that they already have the necessary granulators and shredders. They may have to add metal detectors and safety guards to this equipment, Wolfe said…but then again, maybe not. “Since part contamination is probably not a big issue, the equipment might be fine as is.”
Whether it’s fine as is or in need of an upgrade, recycling equipment has to be able to satisfy the unique, all-important calculus by which that industry measures success: throughput. “Hitting a high level of throughput is unquestionably the big goal in plastics recycling, and it’s a different goal than is applied to pure processing,” said Mike Cyr, vice president of sales with Rotogran International.
This difference is reflected in the machinery, too. “Recycling equipment has to be able to take the punishment of having a wide range of possibly contaminated material stuffed into it,” Cyr said. “Also, because high throughput is the priority, the units have to be simpler to use than other processing equipment.”
The burden of having to handle some potentially unfriendly plastic brings an upside, though: the equipment suppliers have improved their game to meet the challenges. Take, for example, metal contamination – the nemesis of plastics recycling. “Magnets in the hopper throats of granulators and shredders aren’t fool proof ways of eliminating metal, because the metal builds up, which simply delays the problem of it entering the system,” Cyr explained. “Metal detecting is the better choice, and the technology is improving; for example, Rotogran offers a tunnel technology built into the conveyor that creates a magnetic field to divert metal at its smallest size.”
New models of both shredders and granulators are now hitting the market, designed to keep pace with the evolving needs of recyclers. “There are many unique shredder features nowadays that are tailored to specific applications, such as a serrated ram to prevent thin material from jamming the ram, and a ram comb to prevent round pieces from spinning in the chamber,” said Madison Burt, vice president of sales with Weima America.
Specific developments include a new purging recovery system from Maguire that slices or planes lumps of plastic into small pieces and then the pieces into uniform regrind. Also, Harmo is offering a new beside-the-press size reduction machine that can mix sprues and other post-industrial plastic with virgin material to satisfy applications that, as mentioned before, require a percentage of regrind to qualify for the all-important ‘recycled’ designation.
Don’t be surprised that all-new equipment suppliers are popping up, too – for example, PTI Recycling Systems LLC, a subsidiary of Plastics Technologies Inc., formed in 2009 to sell a compact, modular system to produce food-grade, recycled PET resin. “The decision to focus initially on PET recycling was an obvious one,” said Steve Hawksworth, PTI’s president. “There are tremendous market opportunities for recycled PET because, unlike other plastic, it can be rejuvenated to higher quality through the recycling process.” The company’s base unit recycling system, Hawksworth continued, produces 10 million lbs. (4,500 metric tons) of recycled PET annually, and capacity can be doubled with an add-on module. “Our process involves grinding the plastic into powder, decontaminating it and then putting it back into pellet for, which is suitable for most packaging applications,” he said.
Action International Inc. (Vernon, Conn.);
Erema North America Inc. (Ipswich, Mass.);
Harmo Co. Ltd./ Automatisation S.A.B Inc. (Varennes, Que.);
Maguire Canada/Novatec Inc. (Vaughan, Ont.);
PTI Recycling Systems LLC (Holland, Ohio):
Rotogran International Inc. (Concord, Ont.);
Vecoplan LLC (High Point, N.C.);
Greg Parent; 416-678-0154
Weima North America (Fort Mill, S.C.);