Faced with a new processing RFP, Dufferin County sought to understand the costs to manage increasing amounts of bagged recyclables, and whether it would be more cost-effective to debag at the curb or process bagged materials at the MRF. Dufferin provides single stream recycling collection in Blue Boxes, with the option to use clear bags for additional capacity or to handle “overflow”. A 2019 survey showed an average of 36% of households set out bags for some or all of their Blue Box material. This raised concerns about the possibility of higher processing costs in their upcoming MRF contract, leading them to evaluate how to manage bags by studying the impacts of debagging on collection times and potential processing costs.
Across Canada, a number of curbside collection programs permit the use of clear bags to collect recyclables. There are many reasons why municipalities allow residents to bag recyclables, including:
- Overflow for special occasions
- Ease of set-out for rural/seasonal/senior residents
- Less roadside litter
- Straightforward contractor collection and low recycling participation
- Lower moisture in materials for processing
Although bagged materials can reduce stop times at the curb, they create processing challenges at the MRF, such as increased capital costs for debagging equipment, increased downtime, production losses and bale contamination. These challenges can translate to increased processing costs, especially for MRFs not designed to handle bagged materials.
Debagging at curb
In October 2019, AET Group Inc. completed a time-and-motion study of collection operators handling recyclable materials from 1,200 homes over four days. In some areas, collection operators opened recycling bags placed at the curb, emptied the contents into the truck, and placed the empty bag in a receptable affixed to the truck.
The results of the study provided insights into residential set outs, timing, and the costs associated with debagging at the curb. It is important to note, this study offered a preliminary picture and did not take into account different times of year, weather, worker experience level, contamination rates, or resident generation.
It was observed that 67% of homes used only bins, 9% used only bags, and 24% deployed a mix of both bags and bins. As the chart suggests, debagging more than doubled the average stop per household, with an increase of 10.8 seconds/house. With an estimated $50/hour truck fee and a 76% participation rate, the added time translates to an estimated $7.80/household/year increase.
Process pricing proposals not impacted by percentage of bagged materials
Under Dufferin’s processing RFP, proponents were asked to price options with 5% and 33% bagged content. When comparing submitted proposals, the price per tonne to manage 5% bagged material was not significantly different when compared to the price to process 33% bagged material. This may have been because the receiving facilities already had bag breaking equipment and Dufferin’s low annual tonnage would represent a small proportion of total recyclables processed overall. With no additional capital investments at the associated MRF required, the percentage of bagged materials inbound from Dufferin may have been inconsequential.
Manage bags at curb or MRF?
A comparison of both options revealed that debagging at the MRF resulted in a 1% increase in cost versus an estimated 17% increase to debag manually during curbside collection. Therefore, managing bags at the MRF proved to be the lower cost option for Dufferin.
Bye, Bye Bags. Bagged recycling in other jurisdictions
Processing recyclables with bags is problematic within a MRF. Even with the technology available, bags negatively impact other commodities, result in plant downtime, and have inconsistent and low value as a commodity, with very few buyers, if any at all.
Recycle BC phased out one-use blue recycling bag collection on July 1, 2020. In a 2018 Globe and Mail article, Allen Langdon, former managing director of Recycle BC, said that they “hadn’t found a bag breaker that worked successfully in their processing facilities. There just didn’t seem to be a way to efficiently use a bag breaker to break [blue bags]. And that’s why most everyone in BC right now is manually breaking them.”
In Ontario, as of June 1, 2020, Essex Windsor Solid Waste Authority banned bags stating that “the recycling plant is not designed to process plastic bags and [the bags] cause operational issues (e.g., increased downtime, maintenance, repairs), as well as increased contamination levels in final end markets and disposal costs”. In the fall of 2019, Northumberland County shifted from bagged single stream to boxed dual stream recycling and have seen a reduction in contamination levels and improvements in marketed tonnes.
Bagged recycling has its challenges, but local circumstances matter
Like glass, few MRF operators want to see bags at the recycling facility, as they cause processing challenges. However, for various reasons, residents and some collection operators prefer the convenience of putting recycling into bags. For Dufferin, the marketplace clearly signaled that with up to 33% of set-out Blue Box materials, bags can arrive at the MRF without any significant processing price increases. In Dufferin’s case, it costs more to de-bag at the curb than to process at the MRF.
In this situation, given the outcome of the research, Dufferin is moving forward and leaving the bagged Blue Box materials to be managed at the MRF. A lesson we can take from Dufferin County, is that it pays to evaluate the alternatives in your particular situation. Although the larger trend shows a shift away from bagged recyclables for good reason, in Dufferin County it does not make fiscal sense to implement.