What is an Energy from Waste (EFW) Facility?
An EFW facility incinerates non-hazardous solid waste for the purpose of producing energy. This facility has been open since 1992. Algonquin Power Systems Inc. operates the EFW facility in Brampton. Of the 174,000 tonnes of solid waste being processed each year, approximately 160,000 tonnes is residential waste from the Region of Peel. The remainder of the waste processed at the facility is international airport waste and industrial, commercial and institutional (IC&I) waste.
Environmental Controls
Stack emissions are continuously monitored and results are submitted to the Ministry of Environment (MOE) on a monthly basis. The Region of Peel also contracts an independent consultant to conduct stack testing on the facility. Emission results are discussed at Public Liaison Committee meetings held by the Region of Peel approximately every two months. The Liaison Committee also acts as a public forum, where public concerns are addressed.
Facility Operations
There are three sections of the EFW facility:
- Tipping Floor
- Two-Stage Incinerators
- Air Pollution Control (APC) System with Selective Catalytic Reduction (SCR)
Tipping Floor
Collection
trucks deliver waste to the facility and unload it onto
the tipping floor. The tipping floor acts as a buffer or
storage area for the waste prior to being loaded into the
incinerator. Here, large items such as mattresses and bicycles
are removed
Two-Stage Incinerators
The waste is loaded into the five two-stage incinerators from the tipping floor by a front-end loader. Transfer rams feed the primary chamber of the incinerators where the waste is combusted in a controlled air environment (first stage). Off gases are moved into a second chamber where they are combusted in an oxygen-rich environment (second stage). The heat generated in the second stage is fed into a heat recovery boiler creating steam used to run a turbine and generate electricity. The ash remaining from the incineration process in the first stage (bottom ash) is moved into a quench tank to cool. It takes approximately five hours to burn the processed waste from the time the waste is loaded into the primary chamber until the bottom ash is discharged from the quench tank.
Air Pollution Control (APC)
The APC system includes: a wet-spray humidifier to cool and humidify flue gases; a venturi dry lime injection tower to remove acidic gases; a powdered activated carbon (PAC) injection system to reduce mercury; a baghouse filtering system to remove particulate and a selective catalytic reduction (SCR) reactor to reduce the Nitrous Oxides (NOx) emissions, dioxins and furans. This state-of-the-art APC system ensures that emissions from the facility are well below provincial air emission standards.
Ash Removal and Disposal
Fly ash collected from the baghouse filtering system is hazardous, and is disposed of at a secure hazardous waste landfill site. The bottom ash generated is processed to remove ferrous material and then screened into two size groups. The majority of the processed bottom ash is less than one inch in diameter and is currently being used as landfill daily cover. Research into beneficial end use applications and markets for the processed bottom ash is on-going. Potential applications include asphalt, brick and concrete manufacturing using processed bottom ash as a substitute for traditional granular material.