With news that transition to Full Producer Responsibility was expected to take hold in Ontario, but without a target date, Waterloo Region staff took a close look at the needs of its Material Recovery Centre (MRC).
Since 2012, the Region had moved from 4-stream to 2-stream collection – where glass was commingled with other containers and brought into the MRC to be sorted. This bump in glass now coming into the facility was the first in a series of growing pressures on the container line.
Inbound tonnages of PET, HDPE and other Mixed Plastics were growing. Plans to improve participation rates by reducing garbage bag set out limits and dropping garbage collection frequency from weekly to every other week was expected to further affect the efficiency of the facility.
Region staff got to work on finding solutions with shortest possible payback windows that limited operating cost increases while improving capture rates. Here’s what they’d suggest for municipalities that need to invest during uncertain times:
- Monitor your facility; record and analyze what you observe
- Track the daily equipment performance
- Invest in facility performance audits
Visually monitor your operation closely for red flags
Waterloo’s in-feed conveyor for the container line is at a steep incline due to space limitations. Staff observed the incline was resulting in material roll back, where containers are carried part way up the in-feed conveyor before rolling backward. This was causing inefficiencies and was even more problematic in winter when containers are frozen and heavier.
Material roll back increases the amount of time to convey inbound materials onto the container line. To prevent potential costly overtime needs, staff obtained proposals and quotes on a range of solutions. They successfully implemented the least expensive solution ($13,000), which involved extending the length of cleats on the belt to prevent the rollback.
Track the daily equipment performance
Again, through visual observations, staff noticed the optical sorter did not appear to meet the Region’s needs, particularly due to excessive downtime. In 2015, staff began tracking downtime instances and total downtime minutes, and found that the optical sorter was experiencing the highest numbers in both categories.
The optical sorter vendor suggested an upgrade package as a cost effective way to improve efficiency and reduce downtime, rather than replacing the unit.
The ‘Downtime Minutes’ graph shows how downtime minutes fell off once the optical sorter upgrades were installed at a cost of ~$53,700 vs. replacing the equipment ($170,000+ pre-installation).
During this time staff also recognized that the Programmable Logic Controller (PLC), the computer that runs the entire container processing line, was also a significant source of downtime. It was not communicating well with the various pieces of equipment, and was therefore also upgraded. Again, the ‘Downtime Minutes’ graph shows the positive impact of this decision.
The relatively simple $30,000 upgrade to the PLC was not on Region’s staff radar, but was an unexpected benefit of tracking daily equipment performance.
Invest in facility performance audits
The Region was planning to drive up participation in diversion by reducing garbage bag limits and collection frequency. The movement of glass from outdoor bunkers into the facility for sorting had already created a strain, and this second change was expected to amplify it.
To assess whether the container line required further upgrades, the Region retained consultants to evaluate the performance of all sorting equipment and manual stations, both before and after the garbage collection changes.
The study showed that the efficiency of the glass breaker decreased from 85% (2017) to 67% (2018), providing cost benefit data needed to determine next steps for a glass breaker upgrade.
Questions had been raised about the optical sorter’s ability to keep up with the increased rate of flow through the plant. However, the process audit confirmed the sorter was capable of operating acceptably if the material was properly presented in a single layer on the belt, with space visible all around it.
Further, the audit showed that reworking the cleaning protocols could reduce twice daily shut downs to clean it, thus increasing efficiency.
For more information
For more about insights into how Waterloo made its facility upgrade decisions, view its final report. If you’re interested in more discussions like this one, contact Carrie Nash at email@example.com for more information about the MRF Working Group.
“I can’t emphasize enough the value of the process audits. Initial audits cost roughly $60,000, but each subsequent, follow up audit is less. The guidance they provide in making MRC investments is invaluable.
Not only can the information help prevent costly mistakes, the audits provide the baseline and post data needed to both forecast and verify return on investments. Process audits should be a standard procedure”.
Rachel Vaillancourt, Senior Environmental Manager, Waterloo Region