The incinerator located in the Cape Breton Regional Municipality (CBRM), Nova Scotia, was constructed in 1987 as a collaboration between seven municipal units: the County of Cape Breton and the towns of Dominion, Louisbourg, Glace Bay, New Waterford, North Sydney, and Sydney Mines. (In 1995, these municipal units were amalgamated with the City of Sydney.)
Each year, the incinerator provides for the disposal of 54,000 tonnes of municipal solid waste and 1,400 tonnes of medical waste. It also generates approximately 17-million kilowatt hours of electric energy. The facility consists of two 150-tonne per day mass burn units.
Originally, the facility was constructed with an electrified filter bed for air pollution control. In the early 1990s (in anticipation of new CCME guidelines for municipal incinerators), the air pollution system was upgraded. The system currently consists of a boiler, a conditioning tower, a lime scrubber, activated carbon injection, and a baghouse. The facility has regularly passed the standardized tests prescribed under the guidelines by a considerable margin.
Steam generated from the cooling of the gas stream within the air pollution control system is utilized to drive a 2.5 megawatt electric power generator. The municipality has a long-term contract for sale of this power to Nova Scotia Power Inc.
Bottom ash from the primary chamber is quenched in a quench pit and removed via front-end loader for disposal. This ash represents 10 per cent of the volume of waste charged into the primary chamber. The fly ash is mixed with the bottom ash for disposal in an engineered landfill. Currently the facility has no tip fees. However, the municipality will be installing a scale in the near future and is developing a fee schedule.
In 1997, the facility responded to a call by the provincial government for improvements to provincial medical waste incineration, and offered itself as an alternative to an investment of considerable tax dollars to upgrade a facility in Halifax, Nova Scotia. Testing was performed to verify emissions from the combined (biomedical and municipal waste) incineration which revealed results well within the CCME guidelines. A contract was successfully negotiated and, since January 1998, the CBRM facility has incinerated all of the province’s medical waste.
Written by Paul Oldford, P.Eng. manager of solid waste at the Cape Breton Regional Municipality, Nova Scotia.