An Analytical Model for Methane Oxidation and Migration in Double-Layer Landfill Biocover
Landfill has become one of the main atmosphere methane sources. Biocover systems were proposed to mitigate methane emission by utilizing the biodegradation existing in landfill cover soils. The methane emission from landfill should be estimated by considering the methane oxidation and migration process in the biocover system. For the typical biocover system consisting of a gas distribution layer and a methane oxidation layer, an analytical model is proposed to investigate the mechanism of methane emission. The model is effectively verified against the published experiment results. The influence of effective diffusivity of each layer and advection is investigated. The results reveal that the existing single-layer analytical model cannot be applied to double-layer biocover. Putting soil with high effective diffusivity on that with lower value can better mitigate methane emission from cover. The upward advection in cover soils has significant negative effect on mitigating methane emission and should be strictly controlled.
KeywordsBiocover Analytical model Methane oxidation Double-layer soil
Much of the work described in this paper was supported by the National Natural Science Foundation of China under Grant Nos. 41572265 and 41661130153, the Shanghai Shuguang Program under Grant No. 16SG19, the National Program for Support of Top-Notch Young Professionals, and the Newton Advanced Fellowship of the Royal Society under Grant No. NA150466. The writers would like to greatly acknowledge all these financial supports and express their most sincere gratitude.