The Ontario government in its recent discussion paper: Reducing litter and waste in our communities offered the following: “The increased use of chemical recycling could be used to improve the effectiveness of existing recycling processes and to enable economic growth by expanding the potential end uses for materials that currently are sent to landfill.” This blog, prepared by Dan Lantz of Crows Nest Environmental, looks at chemical recycling and the technological developments taking place around the world.
Chemical recycling technologies are advancing at a fast rate. They offer the opportunity for municipalities and industry to address currently difficult and non-recyclable plastics, including multi-laminated plastics. Together, mechanical and chemical recycling can significantly increase diversion from landfill and keep more material in the circular economy.
Here’s how it works
Chemical recycling typically involves shredding plastics into smaller pieces then mixing the pieces with water, a catalyst or enzyme to break the plastic down into smaller polymer chains or its monomer constituents. These monomers are then separated and recombined into new polymers for use in new products or packaging.
What sets chemical recycling apart from mechanical recycling (i.e., shredding, washing and extrusion of plastics into pellets to make new plastic packaging) is that chemically reconstituted polymers can, in principle, be subjected to the process an infinite number of times thereby creating a true ‘closed loop’ system. Conversely, mechanically recycled plastics can have difficulty meeting the quality specifications of virgin material and can only be recycled several times before their properties are no longer able to meet raw material specifications.
Some definitions of chemical recycling also include the application of heat, pressure or microwaves to create a synthetic gas or oil which can be cracked into common polymer building blocks such as methanol or ethanol.
In Ontario…
The Ontario government is examining where thermal applications should count in the waste hierarchy, i.e., whether or not they should count as diversion. As some chemical recycling technologies rely on the application of heat, whether municipalities will be able to utilize them and have the results count to diversion targets is still undecided. Technologies such as Edmonton, Alberta’s Enerkem and Chester, Nova Scotia’s Renewlogy pyrolysis plants would fall into this grey area.
Technologies
Upwards of 30 different companies around the world have developed or are working on chemical recycling technologies. Many are in the early stages of development, but a number are in small-scale processing now and, under the right economic conditions (i.e., higher oil and gas prices) or regulatory environment, can quickly expand operations.
Pyrolysis-based systems are the most advanced, with a full-scale facility in Oregon, developed by Agilyx. In March 2019, at the Plastics Recycling Conference in Washington, DC, it was reported that if oil can stay above $60/barrel, then the pyrolysis process can be viable from a cost perspective. In the case of Agilyx, one of its main outputs is aviation fuel, highlighting that these are not circular recycling models.
In Canada, GreenMantra, in Brantford uses a thermocatalytic process, at temperatures lower than pyrolysis, with iron and copper-based catalysts to turn polyethylene and polypropylene plastics into different specialty chemical products, including high value waxes. These synthetic waxes carry a higher production cost than petroleum-based waxes, however the supply of petroleum-based waxes are in decline creating a positive market trend for synthetics.
Loop Industries, located in Quebec uses a proprietary depolymerization technology which breaks Polyethylene Terephthalate (PET) into its two base materials Mono Ethylene Glycol (MEG), which is polymerized into polyethylene, and Dimethyl Terephthalate (DMT), which is used to produce terephthalate. The two materials are combined to make new PET commonly found in water bottles. IHS Markets recently (March 2019) reported that for the next three to five years, recycled PET (R-PET) will carry a premium over virgin PET of about 10-30%. They questioned whether companies would pay the premium. However, with the EU Parliament passing a regulation requirement (March 28, 2019) of 25% recycled content plastic in all plastic bottles by 2025, the cost differential may become a simple cost of doing business.
Pyrowave has a patented technology called “Catalytic Microwave Depolymerization (CMD)”. The technology uses microwaves which quickly de-polymerize mixed plastics. Pyrowave, INEOS Styrolution and ReVital Polymers have recently formed a venture to close the loop on polystyrene packaging waste. Polystyvert, located in Montreal, Quebec uses a dissolution process that works on all types of polystyrene: expanded, extruded and injection-moulded. It uses an essential oil which causes polystyrene to dissolve, like sugar in water, in just a few seconds.
Looking to the future
Recognizing the future importance and potential of chemical recycling, a new non-profit organisation, Chemical Recycling Europe, has been created with a goal to establish an industry platform to develop and promote chemical recycling for plastic wastes across Europe. Through increased collaboration with EU institutions, the organization is looking to develop strong relationships across the value chain to increase the opportunities for polymer recycling.
More importantly, there are large investments being made into chemical recycling that could compress the timelines as companies look to meet increasing government regulations on recycled content. Loop has received large investments or supply agreements from major multi-nation companies including Coca-Cola, Pepsico, L-Occitane and Danone. Unilever has invested in another company, CreaCycle, developing a pilot process to manage its sachet (multi-layer laminated) plastic wastes. Procter & Gamble has developed its own chemical recycling process, PureCycle, to produce recycled polypropylene with virgin-like properties.
These are just a few of the examples of companies that are making large investments into chemical recycling. Canada is at the forefront of many chemical recycling projects for PET, PS, HDPE and LDPE. The technologies in operation and under development offer the opportunity to increase the amount of recycled content plastics available for packaging and products. There is anticipation that the Canadian Council of Ministers of the Environment will adopt a minimum recycled-content requirement for plastics packaging of 50% by 2030 as outlined in their Zero Plastic Waste Action Plan. Should this goal be formalized in their policy paper, expected around the end of May 2019, further investments into chemical recycling and an advancing of the capabilities in Canada can be expected and will be needed, if Canada is to achieve its target.