Inventory, mitigation, and valorization of biogas produced in a controlled landfill in Morocco

Household waste is very rich in organic matter and, as a result, produces significant quantities of biogas. In Moroccan landfills, this biogas is often not collected and escapes directly into the atmosphere. To address this problem, the municipality of the controlled landfill is committed to the Moroccan policy of mitigating greenhouse gases in various ways at its controlled landfill, including through the capture and treatment of biogas produced. In 2021, more than 945,000 m³ of biogas was treated in a flare at an average rate of 200 m³/h. The purpose of this study is to inventory the biogas produced at the controlled landfill, in order to maximize capture and to determine the best use for the gas once captured. The analyses carried out at the flare inlet averaged 51% of CH₄. The volume of methane treated is therefore 584,926.65 Nm³ CH₄, which is equal to a mass of 421,147.188 kg CH₄, or a reduction of 11,792.121264 t eq.CO₂. In addition to CH₄, this biogas is composed of 33.8% CO₂, 3% O₂, 24.8 ppm CO, and 396.4 ppm H₂S. Our long-term goal is to gather the information necessary to develop commercial uses for this biogas, as has been done at other similar locations in Morocco, such as cogeneration, which can be envisaged on site with a 637-kWh gas engine, permitting electric autonomy. The thermal energy produced can be sent to the neighboring brickworks. We can extend this research to all Moroccan landfills, so that valorization strategies can be developed together for better control of waste field.