Research on CH₄ Emission Fluxes from Active Terrace Surface of MSW Semi-aerobic Landfills

Methane emission fluxes from active terrace surfaces of different landfilling age of a Minicipal Solid Waste(MSW) semi-anaerobic landfill in Hebei Province were determined by the static chamber/gas chromatographic method. The results showed that significant differences were found among methane emission fluxes, with the maximum and the minimum being 215.51 and 0.13 g/(m²·d), respectively. The methane emission fluxes near the air pipe area were higher than the other areas, and the methane emission fluxes in the morning, noon and afternoon in the same area had small differences, and the emission order was afternoon>noon>morning. Moreover, the average methane fluxes in the areas with 8, 12,16 and 20 months of landfilling age were 4.79, 21.15, 81.04 and 7.44 g/(m²·d), respectively. The methane fluxes increased first and then decreased with the landfilling age and reached the maximum at the 16th month. In addition, methane fluxes from active terrace surfaces of different age areas decreased exponentially with increasing distances from the air pipe.