Written by John Nicholson, Navdeep Randev, and Anastasia Jagdeo
There has been much discussion on the term “circular economy” and the need for individuals, organizations, and governments to think in terms of circular economy. In essence, a circular economy is one in which waste is essentially eliminated. Prior to the modern age, humans were part of the circular economy that exists in nature.
As we may have learned in high school science class, there are cycles in nature including those for carbon, water, and nitrogen. The industrial revolution broke away from natural cycles and created a linear approach to materials and energy management – products were manufactured, served their useful purpose, and then disposed of in a landfill. The circular economy approach attempts to create a circle again through the 3Rs and the 4th R.
In Europe and in other forward-thinking jurisdictions around the world, energy-from-waste is considered the Fourth “R” after the 3Rs (reduce, reuse, recycle). The fourth “R” represents the recovery of energy from waste.
Circular Economics applied in Waste Management
Since 1992, the Emerald Energy-from-Waste (EFW) facility has quietly and unassumingly been part of the 4th R – recovering the energy from municipal solid waste. The facility, originally knowns as Peel Resource Recovery Inc. is situated in an industrial area in north Mississauga, Ontario. In all of its years of operation, there has been nary an odour, noise, or other nuisance complaint formerly brought against the facility. Visitors tend to be amazed when they tour the facility which ends at the emissions stack. Their preconceived notion is that they would see smoke from the stack. In fact, the emissions are invisible on a warm day. On cold days, the visible emissions are water vapour.
For the first twenty years of its operation, the facility’s main source of waste was from the Region of Peel. More recently, it has received waste from several municipalities as well as U-Pak Disposal Ltd., a related company. The facility also specializes in disposing of special waste including contraband seized by various police departments and Canadian Border Services at nearby Pearson Airport.
The facility runs 24-hours a day, 7 day per week. It has a total of five two-unit gasifiers/combustion modules that work in parallel to process 500 tonnes per day of solid waste.
The heat generated from the combustion of waste at the facility is used to turn water into steam. Some the steam is piped to a neighbouring cardboard recycling facility to meet their process needs. The remaining steam is used to generate about 10 MW of electricity. The facility itself consumes about 2 MW and its sells the remainder to the local power utility.
Unfortunately, the electricity generated from the Emerald EFW is not considered renewable under Ontario rules and hence does not receive the premium pricing other forms of the renewable energy receive. There are jurisdictions around the world where EFW is considered a renewable energy source and is priced at a premium.
The volume of waste coming into the facility is reduced by 90 percent through the EFW process and is in the form of either bottom ash or fly ash. The bottom ash is disposed of in a landfill, although the facility has been and continues to look for other uses for it such as an additive to asphalt or in building materials. The facility is working with McMaster University researchers on developing a high-value use for the bottom ash.
The fly ash, by regulation, is considered hazardous and is managed at a hazardous waste landfill.
The facility is currently in the planning stages of an expansion which would involve the addition of more combustion units and an upgrade of its air pollution control system. The plans also include an alternative use of the energy recovered from the waste – the production of hydrogen fuel for the trucks that bring waste to the facility.
The facility is working with researchers at the University of Waterloo and a partner in the automotive industry to work out the details of hydrogen generation and use as a fuel for the trucks the off-load waste at the facility on a daily basis. Preliminary economics and environmental analysis indicate that this is a much more effective use of the heat obtained from the EFW facility.
The Emerald EFW is a shining example of EFW done right in Canada. It has been an underappreciated harbinger what can be accomplished at municipalities throughout the country.