Biological oxidation as a method for mitigation of LFG emission

Methanotrophic microorganisms play a very important role in landfills. Microbial oxidation of methane in the upper layers of waste and landfill biocovers leads to a reduction of methane emissions from landfills by at least 25-30% per year (Nozhevnikova et al. 1993 Chanton Liptay, 2000). The analysis of data on 42 landfills shows that the removal efficiency of methane in landfill biocovers is from 22% in clayey materials to 55%, in sandy materials. The overall mean value across all the studies was 36% 6%, while the range of annual fluctuations observed in the 15 landfills was from 11% to 89% (Chanton et al. 2009). In practice, the share of methanotrophs in the reduction of methane emissions from landfills is much larger than 10% which is assumed in the models of methane emissions. 

The main advantages of biotechnological methods for mitigation of landfill gas emission are low operating and capital costs, low pressure drop, and no further waste streams. The disadvantages are low efficiency of removal of components with high concentration and sensitivity to atmospheric conditions. 

---