Incineration is a dirty word in waste management. The old way of burning trash gave little consideration to air pollution and missed a valuable opportunity to recover energy in the process.
In comparison, a modern waste-to-energy facility has little in common with the older smoke-belching incinerators of the past. Today, waste-to-energy facilities are required to meet such stringent emissions regulations that they are no longer considered to be significant contributors of toxic chemicals to the atmosphere.
To facilitate clean emissions, waste is burned at temperatures as high as 2,000 degrees Fahrenheit to assure complete combustion and minimise the production of toxic by-products such as dioxins. The gases resulting from combustion are sprayed with ammonia to reduce formation of nitrogen oxides, treated with carbon to capture toxins and heavy metals, and subjected to a lime slurry to neutralise acid gases such as sulfur oxides.
A filter bag house captures the particulates generated by the combustion, as well as the resulting reaction materials added to the flue gas by the air pollution control system. To control the efficiency of this complex air pollution control system, the flue gas is monitored continuously for several key components.
To facilitate clean emissions, waste is burned at temperatures as high as 2,000 degrees Fahrenheit to assure complete combustion and minimise the production of toxic by-products such as dioxins.
As a result, municipal waste burns more cleanly than most fossil fuels. With 50 per cent of the carbon dioxide emitted from waste-to-energy plants generally considered to be generated by combusting renewable fuel from the organic portions in the waste stream, the energy harnessed by a plant is also 50 per cent renewable.
In a country with limited space for landfills and a mission to reduce reliance on fossil fuels, waste-to-energy reduces the volume and potential environmental impacts of waste and adds a renewable energy source to the country’s energy portfolio.