Sustainable Landfills

Landfilling is a common waste management solution that is economical but also highly impactful on the environment and climate. Converting organic waste into stable biocarbon is a promising solution.

In 2018, Canada disposed of 25.7 million tonnes of waste in landfills. This is a tremendous amount of waste that contributes significantly to the country’s greenhouse gas emissions. Converting landfill waste into stable biocarbon is a promising solution for improving landfill management and mitigating environmental impacts. Here are some key ways it can be used:

Landfill cover material: Amending landfill cover soils with biochar can enhance their geotechnical properties, such as hydraulic conductivity, compressibility, and shear strength. This improves the stability and performance of the landfill cover system, reducing the risk of erosion, leachate generation, and gas emissions.

Methane oxidation: Biochar has the ability to adsorb and oxidize methane, a potent greenhouse gas emitted from landfills. When incorporated into landfill cover soils, biochar can act as a biofilter, retaining and oxidizing methane emissions, thereby reducing their environmental impact.

Leachate treatment: Biochar exhibits excellent adsorption properties, making it effective in removing various contaminants, including nitrogen compounds, from landfill leachate[1]. By incorporating biochar into leachate treatment systems, the removal efficiency of pollutants can be improved, reducing the environmental burden of leachate discharge.

Soil amendment: Biochar can be used as a soil amendment in landfill cover systems, improving soil fertility, water retention, and aeration. This can promote vegetation growth, enhancing the aesthetic appeal and ecological value of the landfill site.

Carbon sequestration: Biochar is a stable form of carbon that can persist in soils for hundreds to thousands of years. By incorporating biochar into landfill cover soils, it can contribute to long-term carbon sequestration, mitigating greenhouse gas emissions and promoting sustainable waste management practices.

Current Research

Biocarbon can be used to filter organic and inorganic components from landfill leachate, a liquid by-product resulting from rainwater runoff in landfills that poses environmental and health risks. Leachate contains high levels of chemical and biological oxygen demand, along with undesirable organic and inorganic contaminants.

Biocarbon’s properties (numerous pore spaces, a large surface area, and a high cation exchange capacity) make it an efficient medium for capturing heavy metals and toxic liquids present in landfill leachate. Moreover, its alkaline pH helps neutralize the acidity and corrosiveness of leachate, preventing long-term damage to the environment. Biocarbon remains structurally stable and resistant to microbial degradation, ensuring its effectiveness over extended periods.

Our team is currently collaborating with researchers at the University of Manitoba under a Research Manitoba grant to explore biocarbon’s potential for treating landfill leachate, reducing methane emissions and promoting sustainable landfill practices.