Dimethyl sulphide degradation using immobilized Thiobacillus thioparus in a biotrickling filter

Abstract

Gaseous dimethyl sulphide (DMS) was eliminated in a biotrickling filter with Thiobacillus thioparus grown in polyurethane foam cubes as carrier material. The temperature, pH and empty bed residence time of the gas were maintained at 30 °C, 7.0 and 40 s, respectively. In the first 45 days, DMS loads of around 2.0 gDMS m−3 h−1 were fed to the BTF to adapt T. thioparus to DMS consumption, attaining close to 100% removal efficiency (RE) on day 46, and the maximum elimination capacity (EC) was 4.0 gDMS m−3 h−1 with a RE of 77%. The overall performance was enhanced by adding a nitrogen‐enriched (9×) medium but was negatively affected by high superficial liquid velocity (8.18 m h−1) and high pH (>7.5). Sulphate concentrations (up to 10 g L−1) showed no effect. The system supported shock loads up to 58 gDMS m−3 h−1 with increased elimination. With nitrogen‐enriched medium and a pH of 7.0 it was possible to increase the EC of DMS up to a maximum of around 23 gDMS m−3 h−1 with 65% RE.