Study On Efficient Oxidation Of Methane From Landfill By Using Biocover And Biofilter

Methane is one of the most important greenhouse gases, and methane emission from landfill takes a great part of total amount of released methane on the earth. To control methane emission from landfill site, one efficient method is to use biocover and biofilter to oxidate methane. In this paper, the methane oxidation in biocover and biofilter is studied in simulating columns using compost which made by an auto two-direction aeration control mode. Kinetic parameters of methane oxidation of biofilter materials are evaluated.Auto two-direction aeration mode composting can markedly abate the temperature variability over the space. The differences among upper layer, middle layer and bottom layer is small than one-direction aeration mode's. Organic matter is consumed 42%. The organic matter decreasing of various layers are almost same. O₂ and CO₂ concentration keeps steady when aeration direction changed. CO₂ is the most greenhouse gas to this mode and 11.644kg (0.468kgCO₂/kg dw) CO₂ is emitted during composting.The results of simulated biocover show that the methane oxidation rate in column with 1mm compost is 4.8mol·m^-2day^-1。Methane oxidation is not observed in the compost column. To increase the porosity of bilcover will enhance CH₄ oxidation. Ceram pellets as an appendent material can increase CH₄ and O₂ diffusivity. The optimal depth of compost and ceram pellets mixture column is 40～50cm.Methane oxidation rate in biofilter is 25.0g m^-3h^-1, about 7.8 times compared to biocover . Gases profile shows that the whole materials in column contribute to methane oxidation. The efficiency of methane oxidation gets a great benefit from excessive air supply. Methane oxidation rate is increasing with augment of CH₄ concentration. The values obtained for Kinetic parameters Vmax and KM in the experiments are 0.094μmolCH₄ g^-1h^-1 dw and 1.2%.