Potentialities of coupling biological processes (biotrickler/biofilter) for the degradation of a mixture of sulphur compounds

Abstract

This study deals with the potential of biological processes combining a biotrickler and a biofilter to treat a mixture of sulphur-reduced compounds including dimethyl sulphide (DMS), dimethyl disulphide (DMDS) and hydrogen sulphide (H2S). As a reference, duplicated biofilters were implemented, and operating conditions were similar for all bioprocesses. The first step of this work was to determine the efficiency removal level achieved for each compound of the mixture and in a second step, to assess the longitudinal distribution of biodegradation activities and evaluate the total bacteria, Hyphomicrobium sp. and Thiobacillus thioparus densities along the bed height. A complete removal of hydrogen sulphide is reached at the start of the experiment within the first stage (biotrickler) of the coupling. This study highlighted that the coupling of a biotrickling filter and a biofilter is an interesting way to improve both removal efficiency levels (15-20% more) and kinetics of recalcitrant sulphur compounds such as DMS and DMDS. The total cell densities remained similar (around 1 × 10(10) 16S recombinant DNA (rDNA) copies g dry packing material) for duplicated biofilters and the biofilter below the biotrickling filter. The relative abundances of Hyphomicrobium sp. and T. thioparus have been estimated to an average of 10 ± 7.0 and 0.23 ± 0.07%, respectively, for all biofilters. Further investigation should allow achieving complete removal of DMS by starting the organic sulphur compound degradation within the first stage and surveying microbial community structure colonizing this complex system.

Characterization of the microbial community in a biotrickling filter treating a complex mixture of gaseous compounds causing odor nuisance

“…Relative abundance of bacteria at one level (reported as percentage) was calculated as the ratio between the number of a single bacterial genus and the total number of the five genera inoculated in the BTF. The number of bacteria was calculated using the 16 s rRNA gene copy number, assuming that bacteria has the following 16 s rRNA gene copy number per genome: three for A. aminovorans , one for N. europaea , five for M. organophilum , four for R. erythropolis , 41 and two for T. thioparus 42 …”

Biological Waste Air and Waste Gas Treatment: Overview, Challenges, Operational Efficiency, and Current Trends

“…These combinations are commonly used in case of VOC mixtures of strongly divergent polarity with high pollutants loads, so that in case of a single-stage biotrickling filter or biofilter long-term stability seems to be questionable due to expected clogging. As an example, a combination of BTF and BF was used for treatment of H 2 S, dimethyl sulfide and dimethyl disulfide [139]. The water-soluble hydrogen sulfide was completely mineralized in the BTF, while the degradation of the two water-insoluble organosulfur compounds took place in the biofilter.…”