Methane Oxidation in Landfill Cover Soils: A Review

Abstract

Migration of methane (CH₄) gas from landfills to the surrounding environment negatively affects both humankind and the environment. It is therefore essential to develop management techniques to reduce CH₄ emissions from landfills to minimize global warming and to reduce the human risks associated with CH₄ gas migration. Oxidation of CH₄ in landfill cover soil is the most important strategy for CH₄ emissions mitigation. CH₄ oxidation occurs naturally in landfill cover soils due to the abundance of methanotrophic bacteria. However, the activities of these bacteria are influenced by several controlling factors. This study attempts to review the important issues associated with the CH₄ oxidation process in landfill cover soils. The CH₄ oxidation process is highly sensitive to environmental factors and cover soil properties. The comparison of various biotic system techniques indicated that each technique has unique advantages and disadvantages, and the choice of the best technique for a specific application depends on economic constraints, treatment efficiency and landfill operations.