Expanded Polystyrene (EPS) recycling is expanding throughout the province. A number of companies as well as cities around the province have made an effort to reduce the amount of EPS bound for the landfill by purchasing an EPS densifier that enables recycling. EPS is typically 2% polystyrene and 98% gas which makes it problematic to landfill because it’s bulky, very light and when fractured, can be a source of wind-driven litter. Different densifiers work in different ways, though the primary method is to heat and/or pressurize the EPS to reduce the amount of air, and thus the amount of space it takes up. This turns the modified EPS into an ingot, a melted form that becomes smaller and easier to store and transport for recycling. Most groups ship the EPS ingots overseas to China where they are turned into consumer items such as coat hangers, picture frames and cases for computers and appliances.
The Town of Cochrane is diverting 850 – 1100 KG of EPS per month from landfill. They’ve been processing the material since 2009 when they bought a cold compactor. Originally, the Town of Cochrane intended to process all types of post-consumer EPS including: packing foam, meat trays, egg cartons, serving ware foam and packing peanuts. After attempting to run this material through their cold compactor and trying to market the result – it became clear that the cold compactor was really only meant for “Clean White Packing Foam”.
With over five years of EPS processing experience and continued pressure from residents to expand the program to include the other types of post-consumer foam – the Town of Cochrane purchased a thermal foam densifier. The thermal densifier increases not only the type of foam that can be processed but it greatly increases the density of the processed product giving significantly better payload and marketability. In two hours they are able to process up to 300 lbs of EPS, the equivalent of six full sling sacks of unprocessed EPS, turned into six small ingots (weighing 35 lbs each). Cochrane is now looking to swap their cold compactor (still in great working order) in exchange for a vertical baler.
On July 28, the Alberta Plastics Recycling Association presented the City of Airdrie with an award for its innovate efforts in recycling EPS. The City of Airdrie’s Waste and Recycling branch ran a pilot program in 2014 to collect EPS. Since August 2014, the city has collected 4.2 metric tonnes (the equivalent of 790 super sacks of EPS). They have two processors, one is McArthur Fine Furniture in Airdrie. For more info on McArthur’s EPS program follow this link. The primary processor, north of Airdrie, receives two full 53-foot trailers of loose EPS a month, demonstrating the public’s positive participation in the program.
An inaugural trial in Alberta also used existing equipment at the Airdrie depot to bale EPS for shipment to Coquitlam. Airdrie demonstrated that EPS could be baled and reduced in size for much more economical transport.
Aquatera Utilities Inc. operates the Eco Centre and landfill for the City of Grande Prairie. They spent a number of years, eight to be exact, looking for a solution for EPS, the largest contaminator in the depot system. In 2011 they purchased a densifier. Their machine can process 12 sling sacks in an hour, which produces one cubic yard of densified EPS.
They have seen growth in collection amounts since the initiation of the program. Diversion rates of EPS from the landfill since 2011:
2011- 2 metric tonnes (Acquired densifier in August)
2012: 10 metric tonnes
2013: 14 metric tonnes
2014: 16.384 metric tonnes
They as well have gone through trial and error with their densifier. Colored EPS was an issue to process on its own and only densified when they comingled it with white EPS. They found out the hard way that packing peanuts are made from cornstarch. When they put the peanuts through the machine they melted and stuck on the heater head. They also couldn’t read the instructions or labels on their machine, because they were written in Japanese, from a Japanese company. A staff member’s wife was able to translate and provide more insight on the machine’s operation. One step that made the program a success was to introduce pre-processing to remove contamination, considered to be tape, staples or other material mixed in with the EPS because these jam and plug the machine and then harden, making the machine difficult to clean.
“We see the value of EPS recycling in many ways, though the economics are there too,” remarked Amy Horne, Recycling and Curbside Service Manager. “The cost savings we’ve achieved is connected to keeping 800 metric tonnes of EPS out of the landfill. I’ve presented these success rates to groups across the continent to demonstrate the benefits of EPS diversion and recycling.”
Aquatera’s densified EPS is shipped to Asia. They broker their own sales depending on the market and because EPS is made with oil, the sale of the densified material is largely dependent on the price of oil.
The company is committed to increased EPS recycling and for a future plan would love to see a mobile machine available to service the surrounding areas.
Aquatera’s recommendation to groups wanting to buy a densifier would be to conduct research. Amy highly recommends the thermal melt machine which has a densifying ratio of 50:1 compared to the cold compressor which is 15:1. The ingot form is also easier to store outside. Source segregation is also important and requires less work at the depot to sort the material.