Theoretical Study on the Influence of Degradation and Compression Parameters on Gas Pressure in Municipal Solid Waste Landfill

Gas pressure is of great significance to the safe management and operation in a landfill. In this paper, a mathematical model for gas pressure simulation in a landfill was developed and the effects of degradation and compression parameters on gas pressure were studied. The results showed that gas pressure in landfill was continuously decreased under the action of extraction pressure. The internal gas pressure in horizontal direction was smaller than that in vertical direction at the same position due to the heterogeneity and anisotropy of refuse dump. Gas pressure in landfill increased with the increase of compression coefficient, biodegradation strain and biodegradation rate constant. The internal gas pressure was most significantly affected by compression coefficient, followed by biodegradation strain, and biodegradation rate constant had the least influence. The influence ranges were 60 kPa, 6 kPa and 3 kPa, respectively.