Maximizing methane gas extraction

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In most parts of the world, household and commercial non hazardous wastes are collected by the municipality and sent to a sanitary landfill. Shortly after being placed in the landfill, the organic material in the waste starts to biodegrade anaerobically, producing landfill gas, which is 40 to 60% methane. Methane is explosive and a potent greenhouse gas. Previously, landfill operators allowed the landfill gas to naturally dissipate into the atmosphere or migrate through the soil. In recent years, operation practises have changed because of the environmental awareness of the damage caused by the landfill gas and the serious explosions that have taken place. In addition, there is the value of methane as a sustainable fuel source. Accordingly, landfill operators have taken a variety of steps to minimize offsite migration and maximize methane gas collection.  To help maximize landfill gas extraction, a proper numerical model is needed. The proposed three dimensional model will account for the diverse composition of the waste and the changing environmental conditions from site to site. Both aspects make it difficult to maximize gas collection efficiency. To assist with model development on site variability, ground penetrating radar data will be incorporated into the model. In addition the model will be tested by using data from several operating and closed landfills. Finally, research will be conducted on how to treat/clean the extracted landfill gas so that it can be used as an effective energy source.  An important component of the research is access to landfills in Ontario, Alberta and British Columbia.The proposed research satisfies two areas of the Supplemental Strategic competition. The improved understanding of landfill gas extraction satisfies the Healthy Environment and Ecoystems target area, while the use of methane as an energy source addresses the need of Sustainable Energy Systems.