Where do the materials end up?
Understanding Potential End Markets for the London Hefty® EnergyBag® Pilot Project
As a team, we have had many questions around what happens to the materials residents are placing out on the curb or dropping off at one of the City's EnviroDepot. Take a read below for more info on where these hard-to-recycle plastics end up.
The Pilot Project is a recovery program that creates higher value materials and keeps materials out of landfill and is meant to work in conjunction with the City’s Blue Box program. It uses existing curbside recycling infrastructure to capture many plastic materials that can’t currently be recycled, supporting the further development of recycling and recovery end markets.
There are generally four types of plastics recycling/recovery categories, listed and explained below. Potential end uses for the materials collected in the Hefty® orange bags in London fall into categories two through four below.
- Mechanical Recycling
- Mixed Plastics Recycling
- Chemical or Molecular Recycling/Conversion Technologies
- Solid Recovered Fuel
Mechanical recycling involves sorting, cleaning and shredding plastic to make pellets, which can then be fashioned into new products. This approach works very well if plastic items are sorted according to their chemical composition (e.g., polyethylene, polypropylene, polystyrene), as they are now in London. This activity will not change during the Pilot Project.
Existing end markets in Ontario for plastics from London’s Blue Box/Blue Cart program include:
- EFS Plastics (Listowel, Ontario)
- Blue Mountains Plastics Recycling (Shelburne, Ontario)
- ReVital Polymers (Sarnia, Ontario)
The reality is not all plastics can be mechanically recycled (e.g., flexible plastic packaging and hard-to-recycle plastics) and it is these plastics which will be explored as part of the London Hefty® EnergyBag® Pilot Project.
The City of London generally follows the globally accepted Waste Management Hierarchy which promotes mechanical recycling and energy recovery as preferred options (in that order) before using its W12A Landfill.
Mixed Plastics Recycling
The Hefty® EnergyBag® team continues to collaborate and innovate with local manufacturers and recyclers to ensure that London’s Pilot Project, as well as Hefty® EnergyBag® programs across the United States, have suitable end-markets for the collected materials. The team is evaluating alternatives that include the manufacturing of durable composites that could be used as construction materials, plastic lumber, railroad ties, decking, siding, pallets, roads, fillers, outdoor furniture and concrete aggregate in building blocks.
Existing and/or potential local end-markets for hard-to-recycle plastics from London’s Pilot Project include:
- Composite plastic lumber, outdoor furniture
- Aggregates for incorporation into concrete blocks
Chemical or Molecular Recycling / Conversion Technologies
When mechanical recycling end-markets are not available, chemical or molecular recycling/conversion technologies that turn plastic into energy sources or feedstock for fuels and products will be used. This a revolutionary new recycling technology that de-polymerizes the plastic returning it to its original molecules so that it can be recycled to infinity.
There are generally two different technologies used - pyrolysis and gasification.
In pyrolysis, plastic waste is heated (not combusted or burned) in the absence of oxygen to produce liquid mixtures that are like synthetic crude oil. This can be further refined into transportation fuels and potentially into chemical feedstocks and basic chemical elements that could be used to make new virgin polymers/plastics.
Gasification involves heating the waste plastic with air or steam to produce valuable industrial gas mixtures called synthesis gas, or “syngas.” This can then be used to produce fuels, fuel additives or valuable chemicals such as ethanol and methanol.
Pyrolysis and gasification are alternative processes to directly combusting (burning) the plastic. Conversion technologies are chemical reactions and have very low emissions. They do not use direct combustion like energy-from-waste (EFW) and have much lower emissions of sulfur and nitrogen oxides than EFW combustion.
The main goal of energy-from-waste (EFW) is to dramatically reduce the volume of materials that would require landfilling. The heat released from EFW is used to produce steam to drive a turbine and generate electricity but this is really a by-product of the process.
Pyrolysis and gasification produce electricity, fuels and and ultimately chemicals to make new plastics. These processes provide additional options for extending the life of valuable plastics other than EFW.
Solid Recovered Fuel
Hard-to-recycle plastics can be used as an alternative fuel source in the manufacturing of cement. The embedded energy value of plastics offset the use of virgin fossil fuel sources such as coal and coke.
The materials collected via the Hefty® EnergyBag® program in other locations have proven suitable as solid recovered fuel given its high heat value. The materials collected can also be compressed into solid fuel pellets or flakes.
If your organization has a recovery or conversion solution, manufacturing process or a mixed plastic recycling solution that could use materials collected in the Hefty® EnergyBag® pilot project and you would like to be considered, please email Jesus Atias. Dow, North America Sustainability Manager | Packaging & Specialty Plastics.
The Hefty® EnergyBag® program is demonstrating that households can sort out hard-to-recycle materials and recover these valuable resources instead of letting them go to waste in a landfill. There are existing and developing end-markets for flexible plastic packaging and hard-to-recycle plastics. Growing this end-market potential – mixed plastics recycling, to recovering the energy value and/or making the most of each molecule – is part of London’s goal to advance a more circular economy and is a key component of the London Hefty® EnergyBag® Pilot Project.
These details will be updated as more information on end markets becomes available.