Removal of hydrogen sulfide by immobilized Thiobacillus thioparus in a biotrickling filter packed with polyurethane foam

The total amount of biomass immobilized on the carrier was 8.2 ± 1.3 × 1010 cells/g. The optimal values of the operating variables were: pH between 7.0 and 7.5, surface velocity of 5.9 m/h and sulfate concentration below 5 g/L. The critical EC value was 14.9 g S/m3/h (removal efficiency of 99.8%) and the ECmax was 55.0 g S/m3/h (removal efficiency of 79.8%) for an EBRT of 150 s. For loads of 2.89 ± 0.05 and 11.5 ± 0.1 g S/m3/h, the removal efficiency was higher than 99% for an EBRT over 90 s.