Mechanical Recycling Options
Mechanical recycling refers to operations that aim to recover plastics waste via mechanical processes (i.e. grinding, washing, separating, drying, re-granulating and compounding). In mechanical recycling, polymers stay intact, this permits for multiple re-use of polymers in the same or similar product–effectively creating a closed loop.
Although the technical capability exists (in limited quantity), the challenge with existing processes for mechanical recycling of multi-material flexible packaging is the need to know what the incoming resin composition is and keeping it consistent and relatively clean. This makes it highly challenging to use multi-material flexible packaging collected at the curbside where much of this information is unknown and unpredictable.
However, there are some examples we have found of organizations able to effectively mechanically recycle multi-material flexible packaging for specific applications in varying quantities. This list is demonstrative and not meant to be exhaustive.
Mechanical Recycling Technologies
Based in Trenton, NJ, TerraCycle is best known for upcycling of consumer goods into new products. Lesser known is that TerraCycle has a significant in-house ‘plastics to pellets’ team. Using melt-flow technology and compatibilizers, the company can take known multi-material flexible packaging and create new resins for use with other in-house products. Because this process requires an understanding of the resins used within structures, Terracycle limits feedstock to material directly received from manufacturer’s (pre-consumer), or collected through targeted campaigns with select post consumers – their ‘brigade program’. Brigade participants register to collect specific materials and brands only, in return they receive a minimal payment and free shipping for their efforts.
- Reuse into resins permits for greater application into alternative products (i.e. manufactured wood)
- Extensive sortation is needed. For food contact structures, cleaning would be required. This makes collection at the curbside currently impossible.
Zzyzx Polymers is using continuous mechano-chemical compatibilization (CMC) to create new plastics. CMC differs from traditional compatibilization as it does not rely on melting. CMC cools plastics to maintain a solid state and then subjects them to shear force. This force breaks polymers apart. Polymers are then chemically recombined, allowing compositions to bind with other polymers or fillers.
- This process does not require high sortation or cleaning which reduces time, costs and efforts.
- The application of this technology to multi-material flexible packaging still requires an understanding of the resins within the structure. This makes collection at the curbside currently impossible.
EcoGlobal is a US-based company with a mechanical recycling technology that converts a mix of LDPE and other inputs into its Ekopolimer material. The mechanical pressing process enables a high tolerance for incorporating mixed material inputs, including a large variety of multi material films. Their material has been used as access mats for construction and other sectors, shipping crates, walkways and low impact roads, storm drains, agriculture, and building materials. EcoGlobal’s products can enable several decades of useful life for repurposed multi material films. Their production facility is based in the Netherlands and the company is looking to commence construction of a North American headquarters. They are actively seeking long-term partnerships with domestic feedstock suppliers and new end market demonstration projects.
Pros: Can accept mixed plastic waste to use in their products up to 30% non LDPE. Broad range of possible end markets.
Cons: Source material is not in the US. Limited on quantity of multi material films they can take.
Continuous Materials is one of the largest post-consumer and post-industrial waste separation facilities in North America. They produce Continuus EVERBOARD™, a Roof Cover Board that is durable, moisture and mold resistant. Unlike typical gypsum-based roof cover boards, EVERBOARD is manufactured from a proprietary blend of post-industrial and post-consumer plastic and cellulose fiber. EVERBOARD’s plastic cellulose core does not disintegrate or delaminate in the presence of water. Every 1,000 square feet of EVERBOARD installed, reportedly prevents 800 lbs. of plastics and 1,200 lbs of paper from being landfilled.
Pros: Already operating at scale, accepting post-industrial multi-material waste.
Cons: Unclear the amount of multi-material films the product uses or what types it can use specifically.
Founded in 2007, IntegriCo Composites Inc. manufactures composite products made from recycled plastics to create composite railroad ties. Their Louisiana based facility has demonstrated the ability to produce high-volume, quality made IntegriTies™ and secured orders in excess of 400,000 units with various railroad and industrial customers. IntegriCo works with Material Recovery Facilities (MRF) and industrial brands across the United States to source the plastic needed for composite manufacturing. IntegriCo’s advanced technology can process hard-to-recycle plastic that would otherwise be sent to a landfill or incinerator.
Pros: Already operating at scale, accepting post industrial multi material waste.
Cons: Unclear the amount of multi material films the product uses or what types it can use specifically.
Mechanical Recycling with Purification Technologies
Based in Bielfeld, Germany, Saperatec promotes a micro-emulsion technology that can separate the layers inherent to a multi-layered structure in order to recover each of the individual components. This is a five step process:
- Crushing: done in order to create as much contact surface as possible for micro-emulsion.
- Micro-emulsion: highly specialized surfactant is applied in order to reduce the surface tension between layers. After mixing at low temperatures individual layers will sort.
- Washing: After layers separate they are washed and conditioned.
- Sorting: Materials are captured by resin type.
- Drying: materials are dried for resale.
- One of a few currently available technologies which can separate plastic layers to create more defined resins.
- Higher water and energy demand than alternatives as a result of washing and drying requirements.
- Still requires an understanding of structure composition prior to beginning process. This makes it unfeasible for curbside collection programs and limits processing to one structure format at a time.
Cadel De-Inking is a Spanish company with a water based delamination process that combines elements of both mechanical and chemical recycling. Cadel’s initial work focused on deinking technologies for rigid and mono material plastics. Cadel has recently extended into delamination trials for multi-material flexible packaging with promising results for PE/PET, and metalized BOPP/BOPP. Delamination technology is an emerging field which enables the separation of different polymers and cleans them of impurities like inks and adhesives, opening up their use to a wide range of plastics end markets. Cadel currently has one pilot plant in Spain with a 500-1,000kg/h capacity and is looking to expand plants and sales of their technology in Europe, the US, and Canada.
- One of a few The only currently available technology which can separate plastic layers to create more defined resins. A water-based process, which reportedly does not rely on solvents or hazardous chemicals.
- Limited currently to PE/PET, and metalized BOPP/BOPP laminates.