Abstract
Plastic films are abundant, but seldom recycled in the United States (US). It is both economically and operationally challenging to recycle plastic films because their light weight makes accumulating material difficult. Additionally, films are not allowed in most curbside recycling programs in the US because they tangle around equipment used at material recovery facilities (MRFs) and effect a MRFs’ ability to effectively sort other materials. As a result, the only recycling pathway for post-consumer plastic films in the US is retail return collection programs. Currently, only the most abundant type of post-consumer plastic film, polyethylene (PE), is accepted by these programs in the US. Although PE films come in many forms, grocery bags are the most well-known, and therefore most abundant, film in the retail return recycling stream. The New York State (NYS) Plastic Bag Waste Reduction Law prohibits the distribution of single use plastic bags. This work explored how ending the distribution of grocery bags impacted retail return recycling programs for PE films in Western New York. We show that a loss of the most recognizable and abundant PE film results in a 1.4 – 2.8x increase in contamination rates, devaluing films that are still collected. As a result, increased contamination rates may threaten the viability of this recycling pathway. The study also provides a complete speciation of this recycling stream with a novel level of detail, as existing research on this recycling pathway is limited.
Introduction
In the United States (US), 4.2 million tons of post-consumer (residential and commercial sourced) plastic bag, sack, and wrap waste were generated in 2018, but only 0.42 million tons (10%) were recycled (EPA 2020). The low bulk density and small thickness (20–200 µm) of films relative to rigid plastics make recycling post-consumer films operationally and economically challenging (Horodytska et al. 2018). As a result, there are only viable recycling markets for the most abundant post-consumer films in the US, which are polyethylene (PE) films, most commonly high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE). These PE films made up the entirety of the post-consumer plastic films recycled in 2018; recycling of polyvinylchloride (PVC), polypropylene (PP), and polystyrene (PS) films was negligible (EPA 2020). In 2018, 3.42 million tons of post-consumer films generated in the US were PE, meaning only 12.3% of post-consumer plastic films with viable recycling pathways were recovered (EPA 2020).
The primary avenue for recovery of residential PE films in the US is retail return programs. In these programs, stores provide collection bins for customers to bring back used PE films. Drop-off materials are then, typically, combined with commercial PE wraps and films generated by the store (e.g., stretch wrap) before being baled and sold. It is estimated that 57% of the baled material is residential films, 37% is commercial stretch wrap, and 6% is contamination (More Recycling 2019). Accepted materials in retail return programs are variable, ranging from retail bags only to any PE film.
Post time: Dec-15-2022