BioCycle November 2015
Edmonton, Alberta and Peel, Ontario: Urban Centers Embark On AD
Two more Canadian urban centers have approved large-scale anaerobic digestion to handle at least part of their organics recycling programs. Recent decisions by the City of Edmonton, Alberta’s capital, and the Region of Peel, a suburban municipality on Toronto, Ontario’s western border, mean the majority of Canada’s large urban centers now either have or are developing digester facilities.
Edmonton, with a population of about 900,000, will build a high solids digester and combined heat and power (CHP) facility at the city-owned Waste Management Centre. It will initially process 44,000 tons of residential and ICI (industrial-commercial-institutional) source separated organics annually, producing enough biogas to fuel a 1.6 MW generator. There’s potential to later double the digestion capacity. The project will also produce about 17,600 tons/year of digestate, to be composted at the 40-acre site’s existing facility, in operation since 2000. Contracts have been awarded and construction is to start early next year, with operation anticipated in the second half of 2017. In Peel Region, home to 1.3 million people, the municipal council voted in September to start the procurement process for a digester able to process up to 132,000 tons annually of organic feedstocks from an expanded residential collection program. It will replace three aerobic composting facilities.
These new projects reflect the preference in Canada for large, central facilities, often owned and operated by the municipal government and, if not, contracted out to single private sector developers and managers. Toronto, at 2.8 million people the country’s most populous municipality, has one 83,000 tons/year city-owned digester in operation and is revamping a second, originally built as a pilot project, with a capacity of 67,000 tons/year and including a CHP plant.
Surrey, British Columbia, a suburb of Vancouver, with a population of 500,000, has begun construction of an 88,000 tons/year digester. Most of the feedstock will come from the city’s residential curbside collection program with the balance from the commercial sector. The biogas will be upgraded into biomethane and injected into the natural gas pipeline grid. The digestate will be composted.