Toronto, Ontario

View of 25,500 cfm Biofilter at Toronto Mixed Waste Recycling and Organics Processing Facility, showing fan, humidifier and filter beds(2)

This biofilter was installed in 2002 in the north end of Toronto at the Toronto Mixed Waste Recycling and Organics Processing Facility, 35 Vanley Crescent. This facility is owned by the City of Toronto and operated by a consortium lead by CCI Canada Corporation.

The plant treats about 30,000 tonnes of organics per year, mostly source separated organics from Etobicoke. The biofilter handles 25,000 cfm of plant air, with an empty bed residence time of 45 s.

This installation demonstrates several other relevant features to many Ambio biofilter installations:

a) Creative Design and Ability to work within a tight budget:
Originally, there was no money in the budget for odour control on this plant. Ambio was asked to design and build something that would work but that would be very low-priced. We did this by re-using the existing concrete slab from an old composting operation for the bed support, re-using concrete blocks on site for biofilter walls, using the old composting aeration system for a drain, and using parts of the old pipe trench for the fan and humidifier support. This installation including fan, humidifier, ducting around the biofilter, filter material, and secondary humidification system cost less than $240,000.

b) Post-Installation Service:
Ambio has continued to work with the Plant manager over the past three years, long after the lapse of the warranty, to deal with issues as they arise and keep the operation there more or less odour free. There were several limitations of space and budget that we were required to work under, and this we have done successfully.

c) Temperature of the Air:
One of the design issues we were most worried about was the temperature of the air in winter. The plant building was not insulated and we put in writing that we could not guarantee proper performance in late fall, winter, and early spring. The temperature of the air in winter (post-humidification) gets as low as 6 °C, yet the biofilter has performed quite well at this low temperature, certainly not as well as in the summer, but well enough to avoid odour complaints. The main problems have been in the spring and fall when large daily swings in temperature are the norm but even at these times, the odour has not been enough to cause odour complaints, but is slightly noticeable on top of the bed.