H_2S removal and bacterial structure along a full-scale biofilter bed packed with polyurethane foam in a landfill site

摘要

Hydrogen sulfide accumulated under a cover film in a landfill site was treated for 7months by a full-scale biofilter packed with polyurethane foam cubes. Sampling ports were set along the biofilter bed to investigate H_2S removal and microbial characteristics in the biofilter. The H_2S was removed effectively by the biofilter, and over 90% removal efficiency was achieved in steady state. Average elimination capacity of H_2S was 2.21gm~(-3)h~(-1) in lower part (LPB) and 0.41gm~(-3)h~(-1) in upper part (UPB) of the biofilter. Most H_2S was eliminated in LPB. H_2S concentration varied along the polyurethane foam packed bed, the structure of the bacterial communities showed spatial variation in the biofilter, and H_2S removal as well as products distribution changed accordingly. The introduction of odorants into the biofilter shifted the distribution of the existing microbial populations toward a specific culture that could metabolize the target odors.