Estimation of Methane Gas Emission from Solid Waste Disposal Sites in Jalingo, Taraba State of Nigeria

This study aimed to estimate methane gas emissions from two major solid waste disposal sites in Jalingo, Taraba State, Nigeria, and to assess their potential for energy generation. The research involved determining key parameters of the Landfill Gas Emission Model (LandGEM), specifically the methane generation potential (Lo) and the methane generation rate (k). The methodology encompassed a comprehensive characterization of municipal solid waste (MSW) through compositional and proximate analyses at the Mile-six and Pantinapu dumpsites. The LandGEM software was then applied to project methane emissions, followed by a comparative analysis of greenhouse gas (GHG) contributions from current open dumping practices versus potential energy recovery scenarios, including MSW incineration and methane combustion for electricity generation. The findings indicate that Jalingo's MSW is predominantly composed of plastics (29.67%-34.67%) and agricultural/garden waste (28.00%-29.00%), with food waste constituting a smaller but impactful fraction (5.66%-6.00%). Proximate analysis revealed average moisture contents of 25.40% for Mile-six and 28.98% for Pantinapu, with volatile matter at 38.84% and 37.45%, respectively. The LandGEM model projected peak methane emissions several years into the future, with Mile-six peaking at 7.933×10⁵ m³/year in 2040 and Pantinapu at 5.981×10⁵ m³/year in 2047. The unmitigated release of methane from both sites is estimated to result in a significant total CO2 equivalent emission of 15,577.499 tonnes/year. Significantly, the combustion of generated methane for electricity could achieve an 88.18% reduction in CO2 equivalent emissions compared to current open dumping practices. While MSW incineration yields CO2 emissions of 0.367 kg/kWh, methane combustion for energy generation demonstrates higher carbon efficiency at 0.00291 kg/kWh. This study concludes that energy recovery from solid waste, particularly through methane combustion, offers a viable and highly effective strategy for climate change mitigation and sustainable waste management in Jalingo, thereby contributing to Nigeria's national GHG inventory and fulfilling international climate requirements.