In our previous blog, we discussed the opportunities and challenges associated with recycling single-use paper coffee cups, specifically from the end-markets perspective. As a recap, paper coffee-cups contain valuable bleached white fibre used for producing various products such as tissue and toweling. However, most paper coffee cups have a design or logo printed directly onto the paper layer that needs to be removed (de-inked) before it can be recycled. Currently, most of the mills with de-inking capabilities are in the USA.

Since there are domestic end-markets for paper coffee cups, many residents/consumers wonder why these cups are not widely accepted in recycling programs. This brings us to the second key challenge in the recycling of paper coffee cups, sorting them at materials recovery facilities (MRFs). MRFs use a combination of manual sorters and automated equipment to separate recyclables collected from municipal programs into valuable commodities. One specific type of equipment used for sorting recyclables is a near-infrared (NIR) optical sorter that uses a NIR sensor to “read” each material that passes under it to identify and sort out targeted materials. Typically, optical sorters have been used to separate plastic materials based on their resin code (#1 to #7) and/or polycoat cartons. There have been previous attempts to use optical sorters to target coffee cups but with mixed and less than ideal results.

As with all technologies and industries, the manufacturers of optical sorters have improved the programming and technology used to identify materials. This has enabled optical sorters to identify more-complex materials. Last year, Reclay StewardEdge (RSE) conducted a study at the TOMRA research and development lab in Germany, to test if the new developments enable optical sorters to effectively sort coffee cups.

RSE tested four scenarios to account for the different ways coffee cups could flow in a MRF. The testing also explored the ability for the optical sorter to recognize both coffee cups and cartons at the same time, as some end-markets can handle coffee cups blended with cartons.

Scenarios:

  1. Coffee cups blended with cartons only.
    **optical sorter targeting coffee cups only.
  1. Coffee cups blended with fibre materials and cartons.
    **optical sorter targeting coffee cups only.
  1. Coffee cups blended with container materials (includes cartons).
    **optical sorter targeting coffee cups only.
  1. Coffee cups blended with container materials (includes cartons).
    **optical sorter targeting coffee cups and cartons.

In each of these scenarios, the tests measured the effectiveness of the optical sorter to recognize and sort coffee cups. It also provided insight into the flexibility of the optical sorter to change the materials being targeted to react to potential market changes.

The optical sorter was able to effectively capture 80% – 95% of the targeted material(s), with a purity of >87%. The highest recovery of coffee cups was found in Scenario 1, as expected, as this represented the least complex mix of materials. The lowest recovery of coffee cups was found to be in Scenario 3, at 83%. It appeared that the film within a container stream hindered the optical sorter’s ability to recognize and sort coffee cups.

It is evident that optical sorters can be effective at sorting cups, at least in a controlled setting.  As the recycling stream continues to evolve with the introduction of new and more complex packaging, municipalities and MRF operators must look to advancements in sorting technology to maximize diversion. Technology advancements will be critical in helping stakeholders achieve a Circular Economy, where recyclable materials can be recovered and made into new products. It can also lead to developing strong domestic markets, as domestic markets typically have lower tolerance for contaminants compared to foreign markets. Improved quality of bales can support these efforts and reduce our dependency on foreign markets. The need to develop domestic markets has reached a critical point, as the prices of some fibre commodities have dropped to lows that have not been experienced since the market crash of 2009.

Overall, there needs to be a multi-pronged approach to tackle the issue of coffee cups. A collaborative effort by industry, municipalities, waste management companies and technology suppliers is required to effectively and efficiently recycle cups and create long-term environmental and economic solutions for managing this material. The Foodservice Packaging Institute (FPI) has launched an initiative to promote the collection of coffee cups, as well as other foodservice packaging (e.g. pizza boxes, deli trays, etc.) in curbside recycling programs where markets exist.  Thus far, programs were initiated in Washington, D.C., Chattanooga, Tennessee and Louisville, Kentucky. Combined they enable approximately 460,000 households to recycle packaging including paper and plastic cups, containers, pizza and sandwich boxes, and paper bags in their curbside carts and bins.

These efforts serve as examples of the positive change required. However, there is still much to be done in terms of minimizing the environmental impacts of single-use coffee cups – particularly those that end up as litter – and developing a strong end market demand for them. RSE has considerable experience in MRF optimization and end market development. Leveraging our experience and market knowledge, we are constantly working with market stakeholders to improve the recyclability of coffee cups and other materials in Ontario and beyond.

For further information or details on the study, you can reach out to Neil Menezes: nmenezes@Reclaystewardedge.com.