Plasco Energy Group will be starting a test facility for plasma-arc gasification of municipal solid waste at the Trail Road landfill near Ottawa, Canada.
Canadian cities such as Ottawa and Toronto have been looking at waste-to-energy technology in order to deal with the waste that is currently either landfilled in Canada or shipped to the United States.
Traditional waste-to-energy facilities use incineration, where waste is aerobically combusted at about 1000-1500°C. Plasma facilities use an electrical "plasma torch" to ionize a gas - creating temperatures in the range of 10,000°C. The plasma heats the waste up in an anaerobic environment - therefore it does not burn. It is chemically decomposed into elements and simple compounds such as carbon monoxide and silicon dioxide. The resulting gases are also rich in carbon monoxide, hydrogen and methane meaning that they are rich in energy. This gas along with the waste heat from the gasification process goes towards the plant's energy output.
The plasma process offers advantages such as the fact that it is so hot that less dioxin-like compounds aree produced, and the lack of excess air reduced nitrogen oxide production. The high temperatures can increase the volatization of heavy metals, though. The "ash" is not the fine powder form that we are all familiar with - it is a black glass-like substance made up mostly of silica, alumina, and other metal oxides.
