Numerical simulation of gas emission in a sanitary landfill equipped with a passive venting system

The gas emission in a sanitary landfill equipped with a passive venting system was investigated numerically. The Darcy's law was employed to simulate the gas flow in the landfill. We used the first order biodegradation rate in modeling the waste biodegradability. The results show that more than 43.3% gases produced from the waste will emit from the landfill surface for R = 30 m, where R is the half of the well spacing. These indicate that the influence radii (between 30 to 50 m) were overestimated in the designing of the gas collection systems in the Sanjuku and the Taichung City sanitary landfills in Taiwan. This might pose a potential of air pollution and raise chances of fires under such designing.