Study on Gas Pressure Characteristics in Multi-Layered Landfills of Municipal Solid Waste

Abstract

In this treatise one-dimensional mathematical model of gas migration in multi-layered landfills of MSW on seepage mechanics of multi-pore media and Darcy’s seepage law. Analysis of gas migration in multi-layered landfills is carried out for three different cases. The gas pressure distribution characteristics in multi-layered landfills of MSW, the effects of final/internal soil cover, the permeability and thickness of the final soil cover, the permeability and gas generation rate of MSW on the gas pressure distributions are investigated. Results show that the bigger is the ratio of gas generation rate to gas permeability of MSW, the bigger is the gas pressure in a uniform MSW landfill. The gas generation rate of MSW mainly controls the size of gas pressure, and the gas permeability of MSW dominates the gas pressure distribution characteristics in a uniform MSW landfill with a final soil cover. The smaller is the gas permeability of the final soil cover or the bigger is the gas generation rate of MSW the bigger is the gas pressure gradient inside the final soil cover