Methane Oxidation in Landfill Cover Soil

Elimination of methane generated from landfills by biofiltration: a review

“…This biogas contains mainly CH 4 , a colorless and odorless GHG, explosive when its concentration lies in the range 5-15% v/v in air (Perry et al 1997;Tagaris et al 2003), and CO 2 , able to cause respiratory problems when its concentration is greater than 0.5% for a prolonged exposure (Toutant 1994;Reginster 1999;Nikiema et al 2004a). The CH 4 concentrations in biogas, as mentioned in the literature, generally vary from 30 to 70% v/v while the CO 2 concentration varies between 20 and 50% v/v (Humer and Lechner 1999b;Kallistova et al 2005;Murphy and McCarthy 2005;Tsai 2006;Zamorano et al 2006).…”

“…In summer, the CH 4 conversion can reach 50% or more (Bö rjesson et al 1998;Chanton et al 1999;Chanton and Liptay 2000;Perera et al 2002;Spokas et al 2006). On the other hand, the diffusion of atmospheric O 2 is limited and generally, an oxygenated zone of only 0.6-0.8 m is observed (Nozhevnikova et al 1993;Bö rjesson and Svenson 1997;Klusman and Dick 2000;Christophersen and Kjeldsen 2001;Chiemchaisri et al 2001b;Perera et al 2002;Tagaris et al 2003;Crossman et al 2004;Kallistova et al 2005).…”

“…On a landfill site, the use of composts of~0.3-0.6 m deep, instead of soils as an oxidation layer, can double the overall CH 4 elimination because of the availability of nutrients for the bacteria, while the higher porosity level leads in turn to a more satisfactory diffusion of the O 2 uptake (Hilger and Humer 2003). A third layer may be used at the top of the biofilter as a heat retention blanket, which will provide a particularly important practical feature to the biofilter when the atmospheric temperature falls during the winter season (Straka et al 1999;Kallistova et al 2005).…”

Diversity and Dynamics of Methanotrophs within an Experimental Landfill Cover Soil

“…However, our inability to detect Type II methanotrophs in this study may not rule out their presence. Type II methanotrophs Methylosinus and Methylocystis have been detected in other landi lls using dif erent molecular methods, such as 16S RNA gene libraries (Chen et al, 2007;Uz et al, 2003), catalyzed reporter deposition-FISH (CARD-FISH) (Kallistova et al, 2007) or indirect immunol uorescence (Kallistova et al, 2005). Type II methanotrophs were probably much less abundant in our samples than those from these other sites.…”

Can phytocapping technique reduce methane emission from municipal landfills?

“…Overall, the thick cap was 45% more efficient in reducing methane emission compared to the thin cap. The significantly (P<0.001) lower levels of methane in the thick cap than in thin cap could be due to greater exposure of methane to larger volume (depth) of the soil, or an increased rate of oxidation by the soil bacteria (Bogner et al 1997;Khalil et al 1998;Kallistova et al 2005). The differences between thick and thin caps were much larger for the root zone methane (Fig 5) than for surface methane (with the thick cap having less methane than thin cap).…”