title: Methane oxidation in water-spreading and compost biofilters.
abstract: This study evaluated two biofilter designs to mitigate methane emissions from landfill vents. Water-spreading biofilters were designed to use the capillarity of coarse sand overlain by a finer sand to increase the active depth for methane oxidation. Compost biofilters consisted of 238-L barrels containing a 1:1 mixture (by volume) of compost to expanded polystyrene pellets. Two replicates of each type of biofilter were tested at an outdoor facility. Gas inflow consisted of an approximately 1:1 mixture (by volume) of CH4 and CO2. Methane output rates (J(out); g m(-2) day(-1)) were measured using the static chamber technique and the Pedersen et al. (2001) diffusion model. Methane oxidation rate (J(ox); g m(-2) day(-1)) and fraction of methane oxidized (f(ox)) were determined by mass balance. For methane inflow rates (J(in)) between 250 and 500 g m(-2) day(-1), the compost biofilter J(ox), 242 g m(-2) day(-1), was not significantly different (P = 0.0647) than the water-spreading biofilter J(ox), 203 g m(-2) day(-1); and the compost f(ox), 69%, was not significantly different (P = 0.7354) than water-spreading f(ox), 63%. The water-spreading biofilter was shown to generally perform as well as the compost biofilter, and it may be easier to implement at a landfill and require less maintenance.
authors.affiliation: Department of Oceanography, 0102 OSB, West Call Street, Florida State University, Tallahassee 32306, USA. powelson@eng.fsu.edu
authors.forename: David K
authors.initials: DK
authors.lastname: Powelson
authors.forename: Jeffery
authors.initials: J
authors.lastname: Chanton
authors.forename: Tarek
authors.initials: T
authors.lastname: Abichou
authors.forename: Jose
authors.initials: J
authors.lastname: Morales
mesh_terms: D000393:Air Pollutants / Q000378:metabolism*; D000397:Air Pollution / Q000517:prevention & control*; D001419:Bacteria / Q000378:metabolism; D001673:Biodegradation, Environmental; D005374:Filtration; D008697:Methane / Q000378:metabolism*; D010084:Oxidation-Reduction; D012037:Refuse Disposal / Q000379:methods*; D012987:Soil; D014867:Water
chemical_list: D000393:Air Pollutants; D012987:Soil; D014867:Water; D008697:Methane