Performance and Bacterial Community Diversity of a Full-Scale Biofilter Treating Leachate Odor in a Sanitary Landfill Site

Odors, such as the malodorous and toxic hydrogen sulfide (H2S), are released during leachate collection, storage, and treatment. A full-scale biofilter was applied to treat H2S emitted from a leachate equalization basin in a sanitary landfill site. The inlet concentration of H2S was 26.3–213.0 mg m−3. In steady state, total removal efficiency was over 90 % in summer and over 80 % in winter. The maximum elimination capacity achieved 9.1 g m−3 h−1 at a loading rate of 10.5 g m−3 h−1. The biofilter was effective at reducing H2S. Factors on the level of H2S inlet concentration and performance of the biofilter were investigated. The H2S inlet load and removal efficiency relied on ambient and biofilter temperature, respectively. The water containing rate and relative humidity presented seasonal variation, according to which the interval period of irrigation could be optimized. The main product of H2S degradation was sulfate, and sulfur also could be observed from the biofilter. Spatial and temporal shifts in bacterial community composition in the biofilter were determined by polymerase chain reaction-denaturing gradient gel electrophoresis followed by DNA sequence analysis. The present study revealed a correlation between biofilter performance and bacterial community structure, especially in a real application case.