High H2S concentrations abatement in a biotrickling filter: start-up at controlled pH and effect of the EBRT and O2H2S supply ratio

Abstract

[Abstract] In this study, a biotrickling filter reactor was set up and used to treat high concentrations of gaseous H2S. Inoculation was carried out at an inlet H2S concentration of 1,000 ppmv (27.8 g H2S m-3 h-1) and sludge from a municipal wastewater treatment plant (MWWTP) was used as inoculum. After 3 days, removal efficiency (RE) above 98 % was achieved even after the loading rate (LR) was increased up to 55.6 g H2S m-3 h-1 (2,000 ppmv). Operation at such LR, with an empty bed residence time (EBRT) of 180 s and controlled pH of 6.5-7 was carried out during 3 months. The start-up phase, the effect of decreasing EBRTs at constant inlet concentration and the composition of the process end-products in relation to the supplied O2/H2S ratio were studied. Also, a carbon mass balance under steady state conditions was calculated