Removal of Dimethyl Sulphide in a Biotrickling Filter under Thermophilic Conditions

Biotrickling filter (BTF) of odorous containing dimethyl sulfide (DMS) emitted from the sewage sludge drying under thermophilic conditions was investigated. DMS removal efficiencies in the BTF achieved 50%, 65%, 75% at 40, 50, 60°C , respectively. The elimination capacities at 60°C was higher than that of biotrickling filter at 50°C or 40°C. At a bed contact time of 34.4 s, the elimination capacities at 60°C in the BTF was 14 g-DMS.m-3.h-1, which was higher than that of mesophilic biofilter. Sulfur dioxide (SO2) has inhibitory effect to the microbial activity for dimethyl sulfide degradation. Bacterial communities in the BTF, which were assessed by PCR-DGGE, play the dominant role in the biological processes of metabolism, sulfur oxidation, sulfate-reducing and carbon oxidation under thermophilic conditions. These results show that thermophilic biotrickling filter is achievable and open new possibilities for applying BTF to hot odour gas streams from sewage sludge drying.